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Sample records for small terrestrial mammals

  1. Mycobacteria in Terrestrial Small Mammals on Cattle Farms in Tanzania

    PubMed Central

    Durnez, Lies; Katakweba, Abdul; Sadiki, Harrison; Katholi, Charles R.; Kazwala, Rudovick R.; Machang'u, Robert R.; Portaels, Françoise; Leirs, Herwig

    2011-01-01

    The control of bovine tuberculosis and atypical mycobacterioses in cattle in developing countries is important but difficult because of the existence of wildlife reservoirs. In cattle farms in Tanzania, mycobacteria were detected in 7.3% of 645 small mammals and in cow's milk. The cattle farms were divided into “reacting” and “nonreacting” farms, based on tuberculin tests, and more mycobacteria were present in insectivores collected in reacting farms as compared to nonreacting farms. More mycobacteria were also present in insectivores as compared to rodents. All mycobacteria detected by culture and PCR in the small mammals were atypical mycobacteria. Analysis of the presence of mycobacteria in relation to the reactor status of the cattle farms does not exclude transmission between small mammals and cattle but indicates that transmission to cattle from another source of infection is more likely. However, because of the high prevalence of mycobacteria in some small mammal species, these infected animals can pose a risk to humans, especially in areas with a high HIV-prevalence as is the case in Tanzania. PMID:21785686

  2. Differential scaling of locomotor performance in small and large terrestrial mammals.

    PubMed

    Iriarte-Díaz, José

    2002-09-01

    It has been observed that the relationship between locomotor performance and body mass in terrestrial mammals does not follow a single linear trend when the entire range of body mass is considered. Large taxa tend to show different scaling exponents compared to those of small taxa, suggesting that there would be a differential scaling between small and large mammals. This pattern, noted previously for several morphological traits in mammals, has been explained to occur as a result of mechanical constraints over bones due to the differential effect of gravity on small and large-sized forms. The relationship between maximum relative running speed (body length s(-1)) and body mass was analysed in 142 species of terrestrial mammals, in order to evaluate whether the relative locomotor performance shows a differential scaling depending on the range of mass analysed, and whether the scaling pattern is consistent with the idea of mechanical constraints on locomotor performance. The scaling of relative locomotor performance proved to be non-linear when the entire range of body masses was considered and showed a differential scaling between small and large mammals. Among the small species, a negative, although nearly independent, relationship with body mass was noted. In contrast, maximum relative running speed in large mammals showed a strong negative relationship with body mass. This reduction in locomotor performance was correlated with a decrease in the ability to withstand the forces applied on bones and may be understood as a necessary stress reduction mechanism for assuring the structural integrity of the limb skeleton in large species.

  3. Challenges to natural resource monitoring in a small border park: terrestrial mammals at Coronado National Memorial, Cochise County, Arizona

    USGS Publications Warehouse

    Swann, Don E.; Bucci, Melanie; Kuenzi, Amy J.; Alberti, Barbara N.; Schwalbe, Cecil R.; Halvorson, William L.; van Riper, Charles; Schwalbe, Cecil R.

    2010-01-01

    Long-term monitoring in national parks is essential to meet National Park Service and other important public goals. Terrestrial mammals are often proposed for monitoring because large mammals are of interest to visitors and small mammals are important as prey. However, traditional monitoring strategies for mammals are often too expensive and complex to sustain for long periods, particularly in small parks. To evaluate potential strategies for long-term monitoring in small parks, we conducted an intensive one-year inventory of terrestrial mammals at Coronado National Memorial, located in Arizona on the U.S.-Mexico international border, then continued less-intensive monitoring at the site for 7 additional years. During 1996-2003 we confirmed 44 species of terrestrial mammals. Most species (40) were detected in the intensive first year of the study, but we continued to detect new species in later years. Mark-recapture data on small mammals indicated large inter-annual fluctuations in population size, but no significant trend over the 7-year period. Issues associated with the international border affected monitoring efforts and increased sampling costs. Our study confirms that sustained annual monitoring of mammals is probably not feasible in small park units like Coronado. However, comparisons of our data with past studies provide insight into important changes in the mammal community since the 1970s, including an increase in abundance and diversity of grassland rodents. Our results suggest that intensive inventories every 10-20 years may be a valuable and cost-effective approach for detecting long-term trends in terrestrial mammal communities in small natural areas.

  4. Lead concentrations: Bats vs. terrestrial small mammals collected near a major highway

    USGS Publications Warehouse

    Clark, D.R.

    1979-01-01

    Wholebody lead concentrations of two species of bats (big brown and little brown) and three species of terrestrial mammals (meadow voles, white-footed mice, and short-tailed shrews) trapped along the Baltimore-Washington Parkway in 1976 are compared, including embryo lead concentration. These data are also compared to those of previous studies conducted in Illinois and Virginia within 20 miles of highways with high traffic volumes. Minimum dosages of various lead compounds that cause mortality or reproductive impairment in six species of domestic mammals (horses, cattle, sheep, dogs, rats, and mice) are noted.

  5. Radionuclides in the terrestrial ecosystem near a Canadian uranium mill--Part II: Small mammal food chains and bioavailability.

    PubMed

    Thomas, P A

    2000-06-01

    Food chain transfer through the soil-vegetation-small mammal food chain was measured by concentration ratios (CRs) for uranium, 226Ra, 210Pb, and 210Po at three sites near the Key Lake uranium mill in northern Saskatchewan. Plant/soil CRs, animal carcass/GI tract CRs, and animal/soil CRs were depressed at sites impacted by mill and tailings dusts relative to a nearby control site. Thus, radionuclides associated with large particulates in tailings and/or ore dusts may be less bioavailable to terrestrial plants and animals than natural sources of radioactive dust. These results show that reliance on default food chain transfer parameters, obtained from uncontaminated terrestrial ecosystems, may overpredict impacts at uranium mine and mill sites. Given the omnivorous diet of small mammals and birds, animal/soil CRs are recommended as the most cost-effective and robust means of predicting animal concentrations from environmental monitoring data at uranium mill facilities.

  6. Radionuclides in the terrestrial ecosystem near a Canadian uranium mill -- Part 2: Small mammal food chains and bioavailability

    SciTech Connect

    Thomas, P.A.

    2000-06-01

    Food chain transfer through the soil-vegetation-small mammal food chain was measured by concentration ratios (CRs) for uranium, {sup 226}Ra, {sup 210}Pb, and {sup 210}Po at three sites near the Key Lake uranium mill in northern Saskatchewan. Plant/soil CRs, animal carcass/GI tract CRs, and animal/soil CRs were depressed at sites impacted by mill and tailings dusts relative to a nearby control site. Thus, radionuclides associated with large particulates in tailings and/or ore dusts may be less bioavailable to terrestrial plants and animals than natural sources of radioactive dust. These results show that reliance on default food chain transfer parameters, obtained from uncontaminated terrestrial ecosystems, may overpredict impacts at uranium mine and mill sites. Given the omnivorous diet of small mammals and birds, animal/soil CRs are recommended as the most cost-effective and robust means of predicting animal concentrations from environmental monitoring data at uranium mill facilities.

  7. An assessment of non-volant terrestrial vertebrates response to wind farms--a study of small mammals.

    PubMed

    Łopucki, Rafał; Mróz, Iwona

    2016-02-01

    The majority of studies on the effects of wind energy development on wildlife have been focused on birds and bats, whereas knowledge of the response of terrestrial, non-flying vertebrates is very scarce. In this paper, the impact of three functioning wind farms on terrestrial small mammal communities (rodents and shrews) and the population parameters of the most abundant species were studied. The study was carried out in southeastern Poland within the foothills of the Outer Western Carpathians. Small mammals were captured at 12 sites around wind turbines and at 12 control sites. In total, from 1200 trap-days, 885 individuals of 14 studied mammal species were captured. There was no difference in the characteristics of communities of small mammals near wind turbines and within control sites; i.e. these types of sites were inhabited by a similar number of species of similar abundance, similar species composition, species diversity (H' index) and species evenness (J') (Pielou's index). For the two species with the highest proportion in the communities (Apodemus agrarius and Microtus arvalis), the parameters of their populations (mean body mass, sex ratio, the proportion of adult individuals and the proportion of reproductive female) were analysed. In both species, none of the analysed parameters differed significantly between sites in the vicinity of turbines and control sites. For future studies on the impact of wind turbines on small terrestrial mammals in different geographical areas and different species communities, we recommend the method of paired 'turbine-control sites' as appropriate for animal species with pronounced fluctuations in population numbers.

  8. Contrasting coloration in terrestrial mammals

    PubMed Central

    Caro, Tim

    2008-01-01

    Here I survey, collate and synthesize contrasting coloration in 5000 species of terrestrial mammals focusing on black and white pelage. After briefly reviewing alternative functional hypotheses for coloration in mammals, I examine nine colour patterns and combinations on different areas of the body and for each mammalian taxon to try to identify the most likely evolutionary drivers of contrasting coloration. Aposematism and perhaps conspecific signalling are the most consistent explanations for black and white pelage in mammals; background matching may explain white pelage. Evidence for contrasting coloration is being involved in crypsis through pattern blending, disruptive coloration or serving other functions, such as signalling dominance, lures, reducing eye glare or in temperature regulation has barely moved beyond anecdotal stages of investigation. Sexual dichromatism is limited in this taxon and its basis is unclear. Astonishingly, the functional significance of pelage coloration in most large charismatic black and white mammals that were new to science 150 years ago still remains a mystery. PMID:18990666

  9. Dietary characterization of terrestrial mammals

    PubMed Central

    Pineda-Munoz, Silvia; Alroy, John

    2014-01-01

    Understanding the feeding behaviour of the species that make up any ecosystem is essential for designing further research. Mammals have been studied intensively, but the criteria used for classifying their diets are far from being standardized. We built a database summarizing the dietary preferences of terrestrial mammals using published data regarding their stomach contents. We performed multivariate analyses in order to set up a standardized classification scheme. Ideally, food consumption percentages should be used instead of qualitative classifications. However, when highly detailed information is not available we propose classifying animals based on their main feeding resources. They should be classified as generalists when none of the feeding resources constitute over 50% of the diet. The term ‘omnivore’ should be avoided because it does not communicate all the complexity inherent to food choice. Moreover, the so-called omnivore diets actually involve several distinctive adaptations. Our dataset shows that terrestrial mammals are generally highly specialized and that some degree of food mixing may even be required for most species. PMID:25009067

  10. Future hotspots of terrestrial mammal loss

    PubMed Central

    Visconti, Piero; Pressey, Robert L.; Giorgini, Daniele; Maiorano, Luigi; Bakkenes, Michel; Boitani, Luigi; Alkemade, Rob; Falcucci, Alessandra; Chiozza, Federica; Rondinini, Carlo

    2011-01-01

    Current levels of endangerment and historical trends of species and habitats are the main criteria used to direct conservation efforts globally. Estimates of future declines, which might indicate different priorities than past declines, have been limited by the lack of appropriate data and models. Given that much of conservation is about anticipating and responding to future threats, our inability to look forward at a global scale has been a major constraint on effective action. Here, we assess the geography and extent of projected future changes in suitable habitat for terrestrial mammals within their present ranges. We used a global earth-system model, IMAGE, coupled with fine-scale habitat suitability models and parametrized according to four global scenarios of human development. We identified the most affected countries by 2050 for each scenario, assuming that no additional conservation actions other than those described in the scenarios take place. We found that, with some exceptions, most of the countries with the largest predicted losses of suitable habitat for mammals are in Africa and the Americas. African and North American countries were also predicted to host the most species with large proportional global declines. Most of the countries we identified as future hotspots of terrestrial mammal loss have little or no overlap with the present global conservation priorities, thus confirming the need for forward-looking analyses in conservation priority setting. The expected growth in human populations and consumption in hotspots of future mammal loss mean that local conservation actions such as protected areas might not be sufficient to mitigate losses. Other policies, directed towards the root causes of biodiversity loss, are required, both in Africa and other parts of the world. PMID:21844048

  11. Ectoparasites in small exotic mammals.

    PubMed

    Fehr, Michael; Koestlinger, Saskia

    2013-09-01

    Ectoparasites inhabiting the skin are responsible for significant problems in small mammals, owing to ingestion of blood, lymph, sebaceous secretions, and scavenging skin debris, as well as a hypersensitivity reaction to parasite antigen resulting in severe pruritus and subsequent self-trauma-induced lesions. In general practice, the most common diagnosis in exotic pets is an unspecified mite infestation, but other ectoparasites such as lice, fleas, insects, or even helminths may cause dermatologic diseases. If treatment with topical insecticides is planned, the small mammal should be isolated for a few hours to enable drying and spreading of the product.

  12. SMALL MAMMAL USE OF MICROHABITAT REVIEWED

    EPA Science Inventory

    Small mammal microhabitat research has greatly influenced vertebrate community ecologists. There exists a "microhabitat paradigm" that states that sympatry among small mammal species is enabled by differential use of microhabitat (i.e., microhabitat partitioning). However, seve...

  13. Impact of Non-Native Terrestrial Mammals on the Structure of the Terrestrial Mammal Food Web of Newfoundland, Canada

    PubMed Central

    Strong, Justin S.; Leroux, Shawn J.

    2014-01-01

    The island of Newfoundland is unique because it has as many non-native terrestrial mammals as native ones. The impacts of non-native species on native flora and fauna can be profound and invasive species have been identified as one of the primary drivers of species extinction. Few studies, however, have investigated the effects of a non-native species assemblage on community and ecosystem properties. We reviewed the literature to build the first terrestrial mammal food web for the island of Newfoundland and then used network analyses to investigate how the timing of introductions and trophic position of non-native species has affected the structure of the terrestrial mammal food web in Newfoundland. The first non-native mammals (house mouse and brown rat) became established in Newfoundland with human settlement in the late 15th and early 16th centuries. Coyotes and southern red-backed voles are the most recent mammals to establish themselves on the island in 1985 and 1998, respectively. The fraction of intermediate species increased with the addition of non-native mammals over time whereas the fraction of basal and top species declined over time. This increase in intermediate species mediated by non-native species arrivals led to an overall increase in the terrestrial mammal food web connectance and generality (i.e. mean number of prey per predator). This diverse prey base and sources of carrion may have facilitated the natural establishment of coyotes on the island. Also, there is some evidence that the introduction of non-native prey species such as the southern red-backed vole has contributed to the recovery of the threatened American marten. Long-term monitoring of the food web is required to understand and predict the impacts of the diverse novel interactions that are developing in the terrestrial mammal food web of Newfoundland. PMID:25170923

  14. Impact of non-native terrestrial mammals on the structure of the terrestrial mammal food web of Newfoundland, Canada.

    PubMed

    Strong, Justin S; Leroux, Shawn J

    2014-01-01

    The island of Newfoundland is unique because it has as many non-native terrestrial mammals as native ones. The impacts of non-native species on native flora and fauna can be profound and invasive species have been identified as one of the primary drivers of species extinction. Few studies, however, have investigated the effects of a non-native species assemblage on community and ecosystem properties. We reviewed the literature to build the first terrestrial mammal food web for the island of Newfoundland and then used network analyses to investigate how the timing of introductions and trophic position of non-native species has affected the structure of the terrestrial mammal food web in Newfoundland. The first non-native mammals (house mouse and brown rat) became established in Newfoundland with human settlement in the late 15th and early 16th centuries. Coyotes and southern red-backed voles are the most recent mammals to establish themselves on the island in 1985 and 1998, respectively. The fraction of intermediate species increased with the addition of non-native mammals over time whereas the fraction of basal and top species declined over time. This increase in intermediate species mediated by non-native species arrivals led to an overall increase in the terrestrial mammal food web connectance and generality (i.e. mean number of prey per predator). This diverse prey base and sources of carrion may have facilitated the natural establishment of coyotes on the island. Also, there is some evidence that the introduction of non-native prey species such as the southern red-backed vole has contributed to the recovery of the threatened American marten. Long-term monitoring of the food web is required to understand and predict the impacts of the diverse novel interactions that are developing in the terrestrial mammal food web of Newfoundland.

  15. Highly athletic terrestrial mammals: horses and dogs.

    PubMed

    Poole, David C; Erickson, Howard H

    2011-01-01

    Evolutionary forces drive beneficial adaptations in response to a complex array of environmental conditions. In contrast, over several millennia, humans have been so enamored by the running/athletic prowess of horses and dogs that they have sculpted their anatomy and physiology based solely upon running speed. Thus, through hundreds of generations, those structural and functional traits crucial for running fast have been optimized. Central among these traits is the capacity to uptake, transport and utilize oxygen at spectacular rates. Moreover, the coupling of the key systems--pulmonary-cardiovascular-muscular is so exquisitely tuned in horses and dogs that oxygen uptake response kinetics evidence little inertia as the animal transitions from rest to exercise. These fast oxygen uptake kinetics minimize Intramyocyte perturbations that can limit exercise tolerance. For the physiologist, study of horses and dogs allows investigation not only of a broader range of oxidative function than available in humans, but explores the very limits of mammalian biological adaptability. Specifically, the unparalleled equine cardiovascular and muscular systems can transport and utilize more oxygen than the lungs can supply. Two consequences of this situation, particularly in the horse, are profound exercise-induced arterial hypoxemia and hypercapnia as well as structural failure of the delicate blood-gas barrier causing pulmonary hemorrhage and, in the extreme, overt epistaxis. This chapter compares and contrasts horses and dogs with humans with respect to the structural and functional features that enable these extraordinary mammals to support their prodigious oxidative and therefore athletic capabilities.

  16. The evolution of maximum body size of terrestrial mammals.

    PubMed

    Smith, Felisa A; Boyer, Alison G; Brown, James H; Costa, Daniel P; Dayan, Tamar; Ernest, S K Morgan; Evans, Alistair R; Fortelius, Mikael; Gittleman, John L; Hamilton, Marcus J; Harding, Larisa E; Lintulaakso, Kari; Lyons, S Kathleen; McCain, Christy; Okie, Jordan G; Saarinen, Juha J; Sibly, Richard M; Stephens, Patrick R; Theodor, Jessica; Uhen, Mark D

    2010-11-26

    The extinction of dinosaurs at the Cretaceous/Paleogene (K/Pg) boundary was the seminal event that opened the door for the subsequent diversification of terrestrial mammals. Our compilation of maximum body size at the ordinal level by sub-epoch shows a near-exponential increase after the K/Pg. On each continent, the maximum size of mammals leveled off after 40 million years ago and thereafter remained approximately constant. There was remarkable congruence in the rate, trajectory, and upper limit across continents, orders, and trophic guilds, despite differences in geological and climatic history, turnover of lineages, and ecological variation. Our analysis suggests that although the primary driver for the evolution of giant mammals was diversification to fill ecological niches, environmental temperature and land area may have ultimately constrained the maximum size achieved.

  17. Physics of chewing in terrestrial mammals

    PubMed Central

    Virot, Emmanuel; Ma, Grace; Clanet, Christophe; Jung, Sunghwan

    2017-01-01

    Previous studies on chewing frequency across animal species have focused on finding a single universal scaling law. Controversy between the different models has been aroused without elucidating the variations in chewing frequency. In the present study we show that vigorous chewing is limited by the maximum force of muscle, so that the upper chewing frequency scales as the −1/3 power of body mass for large animals and as a constant frequency for small animals. On the other hand, gentle chewing to mix food uniformly without excess of saliva describes the lower limit of chewing frequency, scaling approximately as the −1/6 power of body mass. These physical constraints frame the −1/4 power law classically inferred from allometry of animal metabolic rates. All of our experimental data stay within these physical boundaries over six orders of magnitude of body mass regardless of food types. PMID:28266634

  18. Physics of chewing in terrestrial mammals

    NASA Astrophysics Data System (ADS)

    Virot, Emmanuel; Ma, Grace; Clanet, Christophe; Jung, Sunghwan

    2017-03-01

    Previous studies on chewing frequency across animal species have focused on finding a single universal scaling law. Controversy between the different models has been aroused without elucidating the variations in chewing frequency. In the present study we show that vigorous chewing is limited by the maximum force of muscle, so that the upper chewing frequency scales as the ‑1/3 power of body mass for large animals and as a constant frequency for small animals. On the other hand, gentle chewing to mix food uniformly without excess of saliva describes the lower limit of chewing frequency, scaling approximately as the ‑1/6 power of body mass. These physical constraints frame the ‑1/4 power law classically inferred from allometry of animal metabolic rates. All of our experimental data stay within these physical boundaries over six orders of magnitude of body mass regardless of food types.

  19. Physics of chewing in terrestrial mammals.

    PubMed

    Virot, Emmanuel; Ma, Grace; Clanet, Christophe; Jung, Sunghwan

    2017-03-07

    Previous studies on chewing frequency across animal species have focused on finding a single universal scaling law. Controversy between the different models has been aroused without elucidating the variations in chewing frequency. In the present study we show that vigorous chewing is limited by the maximum force of muscle, so that the upper chewing frequency scales as the -1/3 power of body mass for large animals and as a constant frequency for small animals. On the other hand, gentle chewing to mix food uniformly without excess of saliva describes the lower limit of chewing frequency, scaling approximately as the -1/6 power of body mass. These physical constraints frame the -1/4 power law classically inferred from allometry of animal metabolic rates. All of our experimental data stay within these physical boundaries over six orders of magnitude of body mass regardless of food types.

  20. Habitat patterns in a small mammal community

    SciTech Connect

    Kitchings, J.T.; Levy, D.J.

    1981-11-01

    Microhabitat relationships between four sympatric small mammal species (Peromyscus leucopus, Ochrotomys nuttalli, Blarina brevicauda, and Tamias striatus) were examined to determine if their discriminant analysis of small mammal habitat represented a unique habitat utilization pattern for a specific small mammal community. The authors concluded that habitat is only one of many dimensions to be considered when studying the interactions of sympatric species. Reproductive strategy, activity patterns, and other factors make up the n-dimensional hyperspace of an animal's niche. Thus differences in habitat usage alone cannot be used to determine niche overlap and competition between species. (JMT)

  1. The evolution of acoustic size exaggeration in terrestrial mammals

    PubMed Central

    Charlton, Benjamin D.; Reby, David

    2016-01-01

    Recent studies have revealed that some mammals possess adaptations that enable them to produce vocal signals with much lower fundamental frequency (F0) and formant frequency spacing (ΔF) than expected for their size. Although these adaptations are assumed to reflect selection pressures for males to lower frequency components and exaggerate body size in reproductive contexts, this hypothesis has not been tested across a broad range of species. Here we show that male terrestrial mammals produce vocal signals with lower ΔF (but not F0) than expected for their size in mating systems with greater sexual size dimorphism. We also reveal that males produce calls with higher than expected F0 and ΔF in species with increased sperm competition. This investigation confirms that sexual selection favours the use of ΔF as an acoustic size exaggerator and supports the notion of an evolutionary trade-off between pre-copulatory signalling displays and sperm production. PMID:27598835

  2. How the Red Queen drives terrestrial mammals to extinction.

    PubMed

    Quental, Tiago B; Marshall, Charles R

    2013-07-19

    Most species disappear by the processes of background extinction, yet those processes are poorly understood. We analyzed the evolutionary dynamics of 19 Cenozoic terrestrial mammalian clades with rich fossil records that are now fully extinct or in diversity decline. We find their diversity loss was not just a consequence of "gamblers ruin" but resulted from the evolutionary loss to the Red Queen, a failure to keep pace with a deteriorating environment. Diversity loss is driven equally by both depressed origination rates and elevated extinction rates. Although we find diversity-dependent origination and extinction rates, the diversity of each clade only transiently equaled the implied equilibrium diversity. Thus, the processes that drove diversity loss in terrestrial mammal clades were fundamentally nonequilibrial and overwhelmed diversity-dependent processes.

  3. Solid modeling of fossil small mammal teeth

    NASA Astrophysics Data System (ADS)

    Marschallinger, Robert; Hofmann, Peter; Daxner-Höck, Gudrun; Ketcham, Richard A.

    2011-09-01

    This paper presents an approach to create solid models of fossil small mammal teeth using a combination of microcomputed tomography, object based image analysis and voxel modeling. Small mammal teeth, because of their durability, are widely found in Cenozioc sediments the world over and play a key role in stratigraphy as well as in researching the rapid evolution and the paleogeographic spreading of small mammals. Recent advances in microcomputed tomography make this non-destructive analysis method an ideal data source for high-resolution 3D models of fossil small animal teeth. To derive internally consistent solid models of such fossils from micro-CT imagery, we propose a combination of 3D object based image analysis and solid modeling. Incorporating paleontological expert knowledge in the image processing cycle, object based image analysis yields topologically consistent image stacks classified by the main tooth components—enamel, dentine and pulp. Forwarding these data to a voxel modeling system, they can be quantitatively analyzed in an unprecedented manner: going beyond the possibilities of the state-of-art surface models, solid models are capable of unambiguously portraying the entire object volume—teeth can be peeled by material properties, subvolumes can be extracted and automatically analyzed by Boolean operations. The proposed method, which can be flexibly extended to handle a range of paleontological and geological micro-objects, is demonstrated with two typical fossil small mammal teeth.

  4. Effects of roads on small mammals

    USGS Publications Warehouse

    Adams, L.W.; Geis, A.D.

    1983-01-01

    (1) The study was designed to determine the effects of roads on the diversity, spatial distribution, and density of small mammals. (2) Forty species of small mammal (5859 individuals) were snap-trapped in the study. Data resulted from 144 360 trap-nights of effort for an average of 4.06 captures per 100 trap-nights. (3) Small mammal community structure and density were both influenced by roads. Community structure in right-of-way (ROW) habitat was different from that in adjacent habitat. Five species did not prefer ROW habitat: the golden mouse, dusky-footed woodrat, brush mouse, pinon mouse, and California red-backed vole. However, there were more species present in ROW habitat than in adjacent habitat. Grassland species generally preferred ROW habitat and many less habitat-specific species were distributed in ROW and adjacent habitat. (4) Small mammal density (all species combined) was greater in interstate ROW habitat than in adjacent habitat. This was also true individually for the eastern harvest mouse, white-footed mouse, meadow vole, prairie vole, vagrant shrew. Townsend's vole, and California vole. Small mammal density was less in county road ROWs than in adjacent habitat, probably because of the small size of these areas. The data indicate that ROW habitat and its accompanying edge are attractive no: only to grassland species but also to many less habitat-specific species that make use of the ROW-edge-adjacent habitat complex. (5) Mortality on interstate highways was greatest for those species with highest densities in ROW habitat, and did not appear to be detrimental to populations of these species.

  5. Terrestrial mammal feces: a morphometric summary and description.

    PubMed

    Chame, Marcia

    2003-01-01

    The study of feces of terrestrial mammals brings out biological and ecological data such as the species presence, diet, behaviour, territory, parasitic fauna, and home-range use, which can be applied for conservation projects and support paleoecological research that use coprolites as the main source of study. Although the new biotechnological techniques allow more accurate data, the diagnosis based on morphometric analyses permits the primary identification of the taxonomic group origin to support the best choice of subsequent analyses. We present the compilation list of fecal shape and measurements available in the literature published in North America, Eastern and Southern Africa, Europe, and new data from Brazil. Shape and diameters are the best characteristics for taxonomic identification. Feces were assembled in 9 groups that reflect the Order, sometimes the Family, and even their common origin.

  6. Influenza A virus infections in marine mammals and terrestrial carnivores.

    PubMed

    Harder, Timm C; Siebert, Ursula; Wohlsein, Peter; Vahlenkamp, Thomas

    2013-01-01

    Influenza A viruses (IAV), members of the Orthomyxoviridae, cover a wide host spectrum comprising a plethora of avian and, in comparison, a few mammalian species. The viral reservoir and gene pool are kept in metapopulations of aquatic wild birds. The mammalian-adapted IAVs originally arose by transspecies transmission from avian sources. In swine, horse and man, species-adapted IAV lineages circulate independently of the avian reservoir and cause predominantly respiratory disease of highly variable severity. Sporadic outbreaks of IAV infections associated with pneumonic clinical signs have repeatedly occurred in marine mammals (harbour seals [Phoca vitulina]) off the New England coast of the U.S.A. due to episodic transmission of avian IAV. However, no indigenous marine mammal IAV lineages are described. In contrast to marine mammals, avian- and equine-derived IAVs have formed stable circulating lineages in terrestrial carnivores: IAVs of subtype H3N2 and H3N8 are found in canine populations in South Korea, China, and the U.S.A. Experimental infections revealed that dogs and cats can be infected with an even wider range of avian IAVs. Cats, in particular, also proved susceptible to native infection with human pandemic H1N1 viruses and, according to serological data, may be vulnerable to infection with further human-adapted IAVs. Ferrets are susceptible to a variety of avian and mammalian IAVs and are an established animal model of human IAV infection. Thus, a potential role of pet cats, dogs and ferrets as mediators of avian-derived viruses to the human population does exist. A closer observation for influenza virus infections and transmissions at this animal-human interface is indicated.

  7. [Fleas of small mammals from the northeastern Russian Far East].

    PubMed

    Medvedev, S G; Dokuchaev, N E; Tret'iakov, K A; Iamborko, A V; Kiselev, S V

    2014-01-01

    Results of the study of fleas (Siphonaptera) collected from small mammals (insectivores and rodents) in the Russian Far East (Magadan Province, and Khabarovsk and Kamchatka Territories) are represented. Fourteen flea species were revealed in 17 species of small mammals.

  8. Effects of tillage practices and carbofuran exposure on small mammals

    USGS Publications Warehouse

    Albers, P.H.; Linder, G.; Nichols, J.D.

    1990-01-01

    We compared population estimates, body mass, movement, and blood chemistry of small mammals between conventionally tilled and no-till cornfields in Maryland and Pennsylvania to evaluate the effects of tillage practices and carbofuran exposure on small mammals.

  9. The Gut Bacterial Community of Mammals from Marine and Terrestrial Habitats

    PubMed Central

    Nelson, Tiffanie M.; Rogers, Tracey L.; Brown, Mark V.

    2013-01-01

    After birth, mammals acquire a community of bacteria in their gastro-intestinal tract, which harvests energy and provides nutrients for the host. Comparative studies of numerous terrestrial mammal hosts have identified host phylogeny, diet and gut morphology as primary drivers of the gut bacterial community composition. To date, marine mammals have been excluded from these comparative studies, yet they represent distinct examples of evolutionary history, diet and lifestyle traits. To provide an updated understanding of the gut bacterial community of mammals, we compared bacterial 16S rRNA gene sequence data generated from faecal material of 151 marine and terrestrial mammal hosts. This included 42 hosts from a marine habitat. When compared to terrestrial mammals, marine mammals clustered separately and displayed a significantly greater average relative abundance of the phylum Fusobacteria. The marine carnivores (Antarctic and Arctic seals) and the marine herbivore (dugong) possessed significantly richer gut bacterial community than terrestrial carnivores and terrestrial herbivores, respectively. This suggests that evolutionary history and dietary items specific to the marine environment may have resulted in a gut bacterial community distinct to that identified in terrestrial mammals. Finally we hypothesize that reduced marine trophic webs, whereby marine carnivores (and herbivores) feed directly on lower trophic levels, may expose this group to high levels of secondary metabolites and influence gut microbial community richness. PMID:24386245

  10. The gut bacterial community of mammals from marine and terrestrial habitats.

    PubMed

    Nelson, Tiffanie M; Rogers, Tracey L; Brown, Mark V

    2013-01-01

    After birth, mammals acquire a community of bacteria in their gastro-intestinal tract, which harvests energy and provides nutrients for the host. Comparative studies of numerous terrestrial mammal hosts have identified host phylogeny, diet and gut morphology as primary drivers of the gut bacterial community composition. To date, marine mammals have been excluded from these comparative studies, yet they represent distinct examples of evolutionary history, diet and lifestyle traits. To provide an updated understanding of the gut bacterial community of mammals, we compared bacterial 16S rRNA gene sequence data generated from faecal material of 151 marine and terrestrial mammal hosts. This included 42 hosts from a marine habitat. When compared to terrestrial mammals, marine mammals clustered separately and displayed a significantly greater average relative abundance of the phylum Fusobacteria. The marine carnivores (Antarctic and Arctic seals) and the marine herbivore (dugong) possessed significantly richer gut bacterial community than terrestrial carnivores and terrestrial herbivores, respectively. This suggests that evolutionary history and dietary items specific to the marine environment may have resulted in a gut bacterial community distinct to that identified in terrestrial mammals. Finally we hypothesize that reduced marine trophic webs, whereby marine carnivores (and herbivores) feed directly on lower trophic levels, may expose this group to high levels of secondary metabolites and influence gut microbial community richness.

  11. Small mammal training in the veterinary practice.

    PubMed

    Brown, Susan A

    2012-09-01

    Exotic small mammal patients can experience a great deal of anxiety and fear during a visit to a veterinary practice. The stressful experience may continue at the client's home during medication routines. The experience is at times so stressful to the animal that it damages the relationship of trust with its caregiver. This outcome can be changed through the thoughtful use of desensitization, counterconditioning, environmental management and positive reinforcement training of health care behaviors both in the veterinary practice and in the animal's home. Together the veterinarian and the client can create a low stress experience.

  12. Mars: a small terrestrial planet

    NASA Astrophysics Data System (ADS)

    Mangold, N.; Baratoux, D.; Witasse, O.; Encrenaz, T.; Sotin, C.

    2016-11-01

    Mars is characterized by geological landforms familiar to terrestrial geologists. It has a tenuous atmosphere that evolved differently from that of Earth and Venus and a differentiated inner structure. Our knowledge of the structure and evolution of Mars has strongly improved thanks to a huge amount of data of various types (visible and infrared imagery, altimetry, radar, chemistry, etc) acquired by a dozen of missions over the last two decades. In situ data have provided ground truth for remote-sensing data and have opened a new era in the study of Mars geology. While large sections of Mars science have made progress and new topics have emerged, a major question in Mars exploration—the possibility of past or present life—is still unsolved. Without entering into the debate around the presence of life traces, our review develops various topics of Mars science to help the search of life on Mars, building on the most recent discoveries, going from the exosphere to the interior structure, from the magmatic evolution to the currently active processes, including the fate of volatiles and especially liquid water.

  13. Radionuclides in small mammals of the Saskatchewan prairie, including implications for the boreal forest and Arctic tundra

    SciTech Connect

    Thomas, P.A.

    1995-12-31

    The focus of the study reported was to collect and examine baseline data on radionuclides in small prairie mammal food chains and to assess the feasibility of using small mammals as radionuclide monitors in terrestrial ecosystems, in anticipation of possible future nuclear developments in northern Saskatchewan and the Northwest Territories. The study report begins with a literature review that summarizes existing data on radionuclides in small mammals, their food, the ambient environment in Canadian terrestrial ecosystems, principles of terrestrial radioecology, soil and vegetation studies, and food chain studies. It then describes a field study conducted to investigate small mammal food chains at three southwestern Saskatchewan prairie sites. Activities included collection and analysis of water, soil, grains, and foliage samples; trapping of small mammals such as mice and voles, and analysis of gastrointestinal tract samples; and determination of food chain transfer of selected radionuclides from soil to plants and to small mammals. Recommendations are made for future analyses and monitoring of small mammals. Appendices include information on radiochemical methods, soil/vegetation studies and small mammal studies conducted at northern Saskatchewan mine sites, and analyses of variance.

  14. Body size and extinction risk in terrestrial mammals above the species level.

    PubMed

    Tomiya, Susumu

    2013-12-01

    Mammalian body mass strongly correlates with life history and population properties at the scale of mouse to elephant. Large body size is thus often associated with elevated extinction risk. I examined the North American fossil record (28-1 million years ago) of 276 terrestrial genera to uncover the relationship between body size and extinction probability above the species level. Phylogenetic comparative analysis revealed no correlation between sampling-adjusted durations and body masses ranging 7 orders of magnitude, an observation that was corroborated by survival analysis. Most of the ecological and temporal groups within the data set showed the same lack of relationship. Size-biased generic extinctions do not constitute a general feature of the Holarctic mammalian faunas in the Neogene. Rather, accelerated loss of large mammals occurred during intervals that experienced combinations of regional aridification and increased biomic heterogeneity within continents. The latter phenomenon is consistent with the macroecological prediction that large geographic ranges are critical to the survival of large mammals in evolutionary time. The frequent lack of size selectivity in generic extinctions can be reconciled with size-biased species loss if extinctions of large and small mammals at the species level are often driven by ecological perturbations of different spatial and temporal scales, while those at the genus level are more synchronized in time as a result of fundamental, multiscale environmental shifts.

  15. Small Mammal Sampling in Mortandad and Los Alamos Canyons, 2005

    SciTech Connect

    Bennett, Kathy; Sherwood, Sherri; Robinson, Rhonda

    2006-08-15

    As part of an ongoing ecological field investigation at Los Alamos National Laboratory, a study was conducted that compared measured contaminant concentrations in sediment to population parameters for small mammals in the Mortandad Canyon watershed. Mortandad Canyon and its tributary canyons have received contaminants from multiple solid waste management units and areas of concern since establishment of the Laboratory in the 1940s. The study included three reaches within Effluent and Mortandad canyons (E-1W, M-2W, and M-3) that had a spread in the concentrations of metals and radionuclides and included locations where polychlorinated biphenyls and perchlorate had been detected. A reference location, reach LA-BKG in upper Los Alamos Canyon, was also included in the study for comparison purposes. A small mammal study was initiated to assess whether potential adverse effects were evident in Mortandad Canyon due to the presence of contaminants, designated as contaminants of potential ecological concern, in the terrestrial media. Study sites, including the reference site, were sampled in late July/early August. Species diversity and the mean daily capture rate were the highest for E-1W reach and the lowest for the reference site. Species composition among the three reaches in Mortandad was similar with very little overlap with the reference canyon. Differences in species composition and diversity were most likely due to differences in habitat. Sex ratios, body weights, and reproductive status of small mammals were also evaluated. However, small sample sizes of some species within some sites affected the analysis. Ratios of males to females by species of each site (n = 5) were tested using a Chi-square analysis. No differences were detected. Where there was sufficient sample size, body weights of adult small mammals were compared between sites. No differences in body weights were found. Reproductive status of species appears to be similar across sites. However, sample

  16. Paracoccidioides brasiliensis Infection in Small Wild Mammals.

    PubMed

    Sbeghen, Mônica Raquel; Zanata, Thais Bastos; Macagnan, Rafaela; de Abreu, Kaue Cachuba; da Cunha, Willian Luiz; Watanabe, Maria Angelica Ehara; de Camargo, Zoilo Pires; Ono, Mario Augusto

    2015-12-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis prevalent in Brazil and other Latin American countries. The etiological agents of PCM are the thermo-dimorphic fungi Paracoccidioides brasiliensis and P. lutzii. Taking into account that the natural habitat of Paracoccidioides spp. is still undefined, domestic and wild animals could be useful as indicators of Paracoccidioides spp. presence in endemic areas. The objective of this study was to evaluate the infection of small wild mammals by P. brasiliensis in an endemic area for human PCM. Samples from 38 wild mammals from different species such as Akodon sp., Thaptomys nigrita, Euryoryzomys russatus, Oligoryzomys nigripes, Monodelphis sp., Sooretamys angouya, Abrawayaomys angouya, Abrawayaomys ruschii and Akodontinae sp. were evaluated by ELISA, immunodiffusion, histopathology, nested PCR and culture. The overall positivity to gp43 observed in the ELISA was 23.7%. Samples from heart and liver of one O. nigripes were PCR positive, and the animal was also seropositive to gp43 in ELISA. This study showed that wild animals living in endemic areas for PCM are infected with P. brasiliensis and can be valuable epidemiological markers of the fungus presence in the environment. This is the first evidence of PCM infection in Akodon sp., E. russatus, T. nigrita and O. nigripes.

  17. Influence of alternative silviculture on small mammals

    USGS Publications Warehouse

    Waldien, David L.; Hayes, John P.

    2006-01-01

    HIGHLIGHT: A variety of harvest methods promote diversity within forests while still generating income. For example, recent studies have shown that when dead wood is left on the forest floor during harvest, biodiversity increases. A new Cooperative Forest Ecosystem Research (CFER) program fact sheet summarizes how small mammals respond to dead wood in forests that are harvested with alternative methods. CFER is developing a series of fact sheets about responses to changes in young western Oregon forests. The fact sheets are designed to help resource managers balance management needs, including timber and wildlife. The USGS provides a primary source of financial support for CFER, a consortium of federal and state partners conducting research in support of the Northwest Forest Plan.

  18. Optimising camera traps for monitoring small mammals.

    PubMed

    Glen, Alistair S; Cockburn, Stuart; Nichols, Margaret; Ekanayake, Jagath; Warburton, Bruce

    2013-01-01

    Practical techniques are required to monitor invasive animals, which are often cryptic and occur at low density. Camera traps have potential for this purpose, but may have problems detecting and identifying small species. A further challenge is how to standardise the size of each camera's field of view so capture rates are comparable between different places and times. We investigated the optimal specifications for a low-cost camera trap for small mammals. The factors tested were 1) trigger speed, 2) passive infrared vs. microwave sensor, 3) white vs. infrared flash, and 4) still photographs vs. video. We also tested a new approach to standardise each camera's field of view. We compared the success rates of four camera trap designs in detecting and taking recognisable photographs of captive stoats (Mustelaerminea), feral cats (Felis catus) and hedgehogs (Erinaceuseuropaeus). Trigger speeds of 0.2-2.1 s captured photographs of all three target species unless the animal was running at high speed. The camera with a microwave sensor was prone to false triggers, and often failed to trigger when an animal moved in front of it. A white flash produced photographs that were more readily identified to species than those obtained under infrared light. However, a white flash may be more likely to frighten target animals, potentially affecting detection probabilities. Video footage achieved similar success rates to still cameras but required more processing time and computer memory. Placing two camera traps side by side achieved a higher success rate than using a single camera. Camera traps show considerable promise for monitoring invasive mammal control operations. Further research should address how best to standardise the size of each camera's field of view, maximise the probability that an animal encountering a camera trap will be detected, and eliminate visible or audible cues emitted by camera traps.

  19. Bartonella infection in small mammals and their ectoparasites in Lithuania.

    PubMed

    Lipatova, Indre; Paulauskas, Algimantas; Puraite, Irma; Radzijevskaja, Jana; Balciauskas, Linas; Gedminas, Vaclovas

    2015-01-01

    The Bartonella pathogen is an emerging zoonotic agent. Epidemiological studies worldwide have demonstrated that small mammals are reservoir hosts of Bartonella spp. and their ectoparasites are potential vectors. The aim of this study was to investigate the prevalence of Bartonella infections in small mammals (Rodentia, Insectivora) and their ectoparasites (fleas and ticks) in Lithuania. A total of 430 small mammals representing nine species were captured with live-traps in Lithuania during 2013-2014. A total of 151 fleas representing eight species were collected from 109 (25.8%) small mammals. Five hundred and seventy ticks (Ixodes ricinus) were collected from 68 (16.1%) small mammals. Bartonella DNA was detected in 102 (23.7%) small mammals, 44 (29.1%) fleas and five (3.7%) pooled tick samples. Sequence analysis of 16S-23S rRNA ITS region showed that sequences were identical or similar to Bartonella grahamii, Bartonella taylorii and Bartonella rochalimae. This study is the first investigating the distribution and diversity of Bartonella species in small mammals and their ectoparasites in Lithuania. B. grahamii, B. taylorii, and B. rochalimae were detected in small mammals and their fleas, and B. grahamii in ticks obtained from small mammals.

  20. Predation, Competition, and Abiotic Disturbance: Population Dynamics of Small Mammals

    SciTech Connect

    Yunger, John A.; /Northern Illinois U. /Northern Illinois U.

    1996-01-01

    Predation and food availability have been implicated in annual non-cyclic fluctuations of vertebrate prey at mid-latitudes. The timing and magnitude of these factors are unclear due to a lack of large-scale field experiments, little attention to interactions, and a failure to closely link vertebrate predators with their prey. From October 1992 to January 1996, small mammal populations were censused on eight 0.6 ha plots at monthly intervals in a 32-ha prairie restoration at Fermi National Accelerator Laboratory, Illinois. Terrestrial vertebrate predators were excluded after July 1993 from four of the eight plots and canid diets monitored. Both terrestrial and avian vertebrate predators were excluded in March 1994. During 1993 small mammal densities (i.e., Microtus Pennsylvanicus, Peromyscus leucopus, and P. maniculatus) were relatively high. Following peak densities in late summer, Microtus numbers wer 2-3x greater on exclusion plots relative to controls due to preferential selection of Microtus by canids, as reflected in dits. Following an ice-storm and crash in small mammal numbers (particularly Microtus), vertebrate predator exclusion had no detectable effect on P. leucopus numbers, probably due to an abundance of alternative prey (i.e., Sylvilagus floridanus). Meadow vole numbers began to increase in Fall 1995, and a numerical effect of predator exclusion, similar to that in 1993, was observed. Predator exclusion had no detectable effect on the movements and spatial patterns of Microtus during 1993. There was a significant decrease in home range and a significant increase in home range overlap for P. leucopus on the predator exclusion plots. The change in spatial behavior may be due to interspecific competition with Microtus resulting from increased densities on exclusion plots. Thus, predators had an indirect effect on P. leucopus spatial patterns mediated through M. Pennsylvanicus. The role of food limitation was studied using natural and manipulative

  1. Stress physiology in marine mammals: how well do they fit the terrestrial model?

    PubMed

    Atkinson, Shannon; Crocker, Daniel; Houser, Dorian; Mashburn, Kendall

    2015-07-01

    Stressors are commonly accepted as the causal factors, either internal or external, that evoke physiological responses to mediate the impact of the stressor. The majority of research on the physiological stress response, and costs incurred to an animal, has focused on terrestrial species. This review presents current knowledge on the physiology of the stress response in a lesser studied group of mammals, the marine mammals. Marine mammals are an artificial or pseudo grouping from a taxonomical perspective, as this group represents several distinct and diverse orders of mammals. However, they all are fully or semi-aquatic animals and have experienced selective pressures that have shaped their physiology in a manner that differs from terrestrial relatives. What these differences are and how they relate to the stress response is an efflorescent topic of study. The identification of the many facets of the stress response is critical to marine mammal management and conservation efforts. Anthropogenic stressors in marine ecosystems, including ocean noise, pollution, and fisheries interactions, are increasing and the dramatic responses of some marine mammals to these stressors have elevated concerns over the impact of human-related activities on a diverse group of animals that are difficult to monitor. This review covers the physiology of the stress response in marine mammals and places it in context of what is known from research on terrestrial mammals, particularly with respect to mediator activity that diverges from generalized terrestrial models. Challenges in conducting research on stress physiology in marine mammals are discussed and ways to overcome these challenges in the future are suggested.

  2. Elk herbivory alters small mammal assemblages in high elevation drainages

    USGS Publications Warehouse

    Parsons, Elliott W.R.; Maron, John L.; Martin, Thomas E.

    2012-01-01

    Together, our results show that relaxation of heavy herbivore pressure by a widespread native ungulate can lead to rapid changes in small mammal assemblages. Moreover, exclusion of large herbivores can yield rapid responses by vegetation that may enhance or maintain habitat quality for small mammal populations.

  3. Acute oral toxicity of chemicals in terrestrial life stages of amphibians: Comparisons to birds and mammals.

    PubMed

    Crane, Mark; Finnegan, Meaghean; Weltje, Lennart; Kosmala-Grzechnik, Sylwia; Gross, Melanie; Wheeler, James R

    2016-10-01

    Amphibians are currently the most threatened and rapidly declining group of vertebrates and this has raised concerns about their potential sensitivity and exposure to plant protection products and other chemicals. Current environmental risk assessment procedures rely on surrogate species (e.g. fish and birds) to cover the risk to aquatic and terrestrial life stages of amphibians, respectively. Whilst a recent meta-analysis has shown that in most cases amphibian aquatic life stages are less sensitive to chemicals than fish, little research has been conducted on the comparative sensitivity of terrestrial amphibian life stages. Therefore, in this paper we address the questions "What is the relative sensitivity of terrestrial amphibian life stages to acute chemical oral exposure when compared with mammals and birds?" and "Are there correlations between oral toxicity data for amphibians and data for mammals or birds?" Identifying a relationship between these data may help to avoid additional vertebrate testing. Acute oral amphibian toxicity data collected from the scientific literature and ecotoxicological databases were compared with toxicity data for mammals and birds. Toxicity data for terrestrial amphibian life stages are generally sparse, as noted in previous reviews. Single-dose oral toxicity data for terrestrial amphibian life stages were available for 26 chemicals and these were positively correlated with LD50 values for mammals, while no correlation was found for birds. Further, the data suggest that oral toxicity to terrestrial amphibian life stages is similar to or lower than that for mammals and birds, with a few exceptions. Thus, mammals or birds are considered adequate toxicity surrogates for use in the assessment of the oral exposure route in amphibians. However, there is a need for further data on a wider range of chemicals to explore the wider applicability of the current analyses and recommendations.

  4. Road zone effects in small-mammal communities

    USGS Publications Warehouse

    Bissonette, J.A.; Rosa, S.A.

    2009-01-01

    Our study focused on the putative effects of roads on small-mammal communities in a high desert region of southern Utah. Specifically, we tested whether or not roads create adjacent zones characterized by lower small- mammal densities, abundance, and diversity. We sampled abundance of small mammals at increasing distances from Interstate 15 during two summers. We recorded 11 genera and 13 species. We detected no clear abundance, density, or diversity effects relative to distance from the road. Only two of 13 species were never captured near roads. The abundance of the remaining 11 small mammal species was either similar at different distances from the road or higher closer to the road. We conclude that although roads may act as barriers and possible sources of mortality, adjacent zones of vegetation often provide favorable microhabitat in the desert landscape for many small mammals. ?? 2009 by the author(s).

  5. Phosphatidylcholine composition of pulmonary surfactant from terrestrial and marine diving mammals

    PubMed Central

    Gutierrez, Danielle B.; Fahlman, Andreas; Gardner, Manuela; Kleinhenz, Danielle; Piscitelli, Marina; Raverty, Stephen; Haulena, Martin; Zimba, Paul V.

    2015-01-01

    Marine mammals are repeatedly exposed to elevated extra-thoracic pressure and alveolar collapse during diving and readily experience alveolar expansion upon inhalation – a unique capability as compared to terrestrial mammals. How marine mammal lungs overcome the challenges of frequent alveolar collapse and recruitment remains unknown. Recent studies indicate that pinniped lung surfactant has more anti-adhesive components compared to terrestrial mammals, which would aid in alveolar opening. However, pulmonary surfactant composition has not yet been investigated in odontocetes, whose physiology and diving behavior differ from pinnipeds. The aim of this study was to investigate the phosphatidylcholine (PC) composition of lung surfactants from various marine mammals and compare these to a terrestrial mammal. We found an increase in anti-adhesive PC species in harp seal (Pagophilus groenlandicus) and California sea lion (Zalophus californianus) compared to dog (Canus lupus familiaris), as well as an increase in the fluidizing PCs 16:0/14:0 and 16:0/16:1 in pinnipeds compared to odontocetes. The harbor porpoise (a representative of the odontocetes) did not have higher levels of fluidizing PCs compared to dog. Our preliminary results support previous findings that pinnipeds may have adapted unique surfactant compositions that allow them to dive at high pressures for extended periods without adverse effects. Future studies will need to investigate the differences in other surfactant components to fully assess the surfactant composition in odontocetes. PMID:25812797

  6. Fleas (Siphonaptera) Infesting Small Mammals From The Western Oriental Region.

    PubMed

    Haas, Glenn E.; Walton, Dan W.

    1973-08-01

    Nine species of fleas representing 4 families were collected in 1972 form 14 species of small mammals: 2 hedgehogs, 1 shrew, 2 bats, 8 rodents and 1 mongoose. Most specimens were from 7 localities in Karachi District. Xenopsylla astis accounted for 78% of the 404 fleas collected. Collection data, especially flea-mammal associations and locality records, are presented and discussed.

  7. A potential mechanism for allometric trabecular bone scaling in terrestrial mammals

    PubMed Central

    Christen, Patrik; Ito, Keita; van Rietbergen, Bert

    2015-01-01

    Trabecular bone microstructural parameters, including trabecular thickness, spacing, and number, have been reported to scale with animal size with negative allometry, whereas bone volume fraction is animal size-invariant in terrestrial mammals. As for the majority of scaling patterns described in animals, its underlying mechanism is unknown. However, it has also been found that osteocyte density is inversely related to animal size, possibly adapted to metabolic rate, which shows a negative relationship as well. In addition, the signalling reach of osteocytes is limited by the extent of the lacuno-canalicular network, depending on trabecular dimensions and thus also on animal size. Here we propose animal size-dependent variations in osteocyte density and their signalling influence distance as a potential mechanism for negative allometric trabecular bone scaling in terrestrial mammals. Using an established and tested computational model of bone modelling and remodelling, we run simulations with different osteocyte densities and influence distances mimicking six terrestrial mammals covering a large range of body masses. Simulated trabecular structures revealed negative allometric scaling for trabecular thickness, spacing, and number, constant bone volume fraction, and bone turnover rates inversely related to animal size. These results are in agreement with previous observations supporting our proposal of osteocyte density and influence distance variation as a potential mechanism for negative allometric trabecular bone scaling in terrestrial mammals. The inverse relationship between bone turnover rates and animal size further indicates that trabecular bone scaling may be linked to metabolic rather than mechanical adaptations. PMID:25655770

  8. Examining predator-prey body size, trophic level and body mass across marine and terrestrial mammals.

    PubMed

    Tucker, Marlee A; Rogers, Tracey L

    2014-12-22

    Predator-prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator-prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator-prey ratio across terrestrial (n = 51) and marine (n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator-prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities.

  9. A potential mechanism for allometric trabecular bone scaling in terrestrial mammals.

    PubMed

    Christen, Patrik; Ito, Keita; van Rietbergen, Bert

    2015-03-01

    Trabecular bone microstructural parameters, including trabecular thickness, spacing, and number, have been reported to scale with animal size with negative allometry, whereas bone volume fraction is animal size-invariant in terrestrial mammals. As for the majority of scaling patterns described in animals, its underlying mechanism is unknown. However, it has also been found that osteocyte density is inversely related to animal size, possibly adapted to metabolic rate, which shows a negative relationship as well. In addition, the signalling reach of osteocytes is limited by the extent of the lacuno-canalicular network, depending on trabecular dimensions and thus also on animal size. Here we propose animal size-dependent variations in osteocyte density and their signalling influence distance as a potential mechanism for negative allometric trabecular bone scaling in terrestrial mammals. Using an established and tested computational model of bone modelling and remodelling, we run simulations with different osteocyte densities and influence distances mimicking six terrestrial mammals covering a large range of body masses. Simulated trabecular structures revealed negative allometric scaling for trabecular thickness, spacing, and number, constant bone volume fraction, and bone turnover rates inversely related to animal size. These results are in agreement with previous observations supporting our proposal of osteocyte density and influence distance variation as a potential mechanism for negative allometric trabecular bone scaling in terrestrial mammals. The inverse relationship between bone turnover rates and animal size further indicates that trabecular bone scaling may be linked to metabolic rather than mechanical adaptations.

  10. Prevalence and Genotype Allocation of Pathogenic Leptospira Species in Small Mammals from Various Habitat Types in Germany

    PubMed Central

    Karnath, Carolin; Silaghi, Cornelia; Schex, Susanne; Eßbauer, Sandra; Pfeffer, Martin

    2016-01-01

    Small mammals serve as most important reservoirs for Leptospira spp., the causative agents of Leptospirosis, which is one of the most neglected and widespread zoonotic diseases worldwide. The knowledge about Leptospira spp. occurring in small mammals from Germany is scarce. Thus, this study’s objectives were to investigate the occurrence of Leptospira spp. and the inherent sequence types in small mammals from three different study sites: a forest in southern Germany (site B1); a National Park in south-eastern Germany (site B2) and a renaturalised area, in eastern Germany (site S) where small mammals were captured. DNA was extracted from kidneys of small mammals and tested for Leptospira spp. by real-time PCR. Positive samples were further analysed by duplex and conventional PCRs. For 14 positive samples, multi locus sequence typing (MLST) was performed. Altogether, 1213 small mammals were captured: 216 at site B1, 456 at site B2 and 541 at site S belonging to following species: Sorex (S.) araneus, S. coronatus, Apodemus (A.) flavicollis, Myodes glareolus, Microtus (Mi.) arvalis, Crocidura russula, Arvicola terrestris, A. agrarius, Mustela nivalis, Talpa europaea, and Mi. agrestis. DNA of Leptospira spp. was detected in 6% of all small mammals. At site B1, 25 small mammals (11.6%), at site B2, 15 small mammals (3.3%) and at site S, 33 small mammals (6.1%) were positive for Leptospira spp. Overall, 54 of the positive samples were further determined as L. kirschneri, nine as L. interrogans and four as L. borgpetersenii while five real-time PCR-positive samples could not be further determined by conventional PCR. MLST results revealed focal occurrence of L. interrogans and L. kirschneri sequence type (ST) 117 while L. kirschneri ST 110 was present in small mammals at all three sites. Further, this study provides evidence for a particular host association of L. borgpetersenii to mice of the genus Apodemus. PMID:27015596

  11. Prevalence and Genotype Allocation of Pathogenic Leptospira Species in Small Mammals from Various Habitat Types in Germany.

    PubMed

    Obiegala, Anna; Woll, Dietlinde; Karnath, Carolin; Silaghi, Cornelia; Schex, Susanne; Eßbauer, Sandra; Pfeffer, Martin

    2016-03-01

    Small mammals serve as most important reservoirs for Leptospira spp., the causative agents of Leptospirosis, which is one of the most neglected and widespread zoonotic diseases worldwide. The knowledge about Leptospira spp. occurring in small mammals from Germany is scarce. Thus, this study's objectives were to investigate the occurrence of Leptospira spp. and the inherent sequence types in small mammals from three different study sites: a forest in southern Germany (site B1); a National Park in south-eastern Germany (site B2) and a renaturalised area, in eastern Germany (site S) where small mammals were captured. DNA was extracted from kidneys of small mammals and tested for Leptospira spp. by real-time PCR. Positive samples were further analysed by duplex and conventional PCRs. For 14 positive samples, multi locus sequence typing (MLST) was performed. Altogether, 1213 small mammals were captured: 216 at site B1, 456 at site B2 and 541 at site S belonging to following species: Sorex (S.) araneus, S. coronatus, Apodemus (A.) flavicollis, Myodes glareolus, Microtus (Mi.) arvalis, Crocidura russula, Arvicola terrestris, A. agrarius, Mustela nivalis, Talpa europaea, and Mi. agrestis. DNA of Leptospira spp. was detected in 6% of all small mammals. At site B1, 25 small mammals (11.6%), at site B2, 15 small mammals (3.3%) and at site S, 33 small mammals (6.1%) were positive for Leptospira spp. Overall, 54 of the positive samples were further determined as L. kirschneri, nine as L. interrogans and four as L. borgpetersenii while five real-time PCR-positive samples could not be further determined by conventional PCR. MLST results revealed focal occurrence of L. interrogans and L. kirschneri sequence type (ST) 117 while L. kirschneri ST 110 was present in small mammals at all three sites. Further, this study provides evidence for a particular host association of L. borgpetersenii to mice of the genus Apodemus.

  12. Serial population extinctions in a small mammal indicate Late Pleistocene ecosystem instability.

    PubMed

    Brace, Selina; Palkopoulou, Eleftheria; Dalén, Love; Lister, Adrian M; Miller, Rebecca; Otte, Marcel; Germonpré, Mietje; Blockley, Simon P E; Stewart, John R; Barnes, Ian

    2012-12-11

    The Late Pleistocene global extinction of many terrestrial mammal species has been a subject of intensive scientific study for over a century, yet the relative contributions of environmental changes and the global expansion of humans remain unresolved. A defining component of these extinctions is a bias toward large species, with the majority of small-mammal taxa apparently surviving into the present. Here, we investigate the population-level history of a key tundra-specialist small mammal, the collared lemming (Dicrostonyx torquatus), to explore whether events during the Late Pleistocene had a discernible effect beyond the large mammal fauna. Using ancient DNA techniques to sample across three sites in North-West Europe, we observe a dramatic reduction in genetic diversity in this species over the last 50,000 y. We further identify a series of extinction-recolonization events, indicating a previously unrecognized instability in Late Pleistocene small-mammal populations, which we link with climatic fluctuations. Our results reveal climate-associated, repeated regional extinctions in a keystone prey species across the Late Pleistocene, a pattern likely to have had an impact on the wider steppe-tundra community, and one that is concordant with environmental change as a major force in structuring Late Pleistocene biodiversity.

  13. Establishing macroecological trait datasets: digitalization, extrapolation, and validation of diet preferences in terrestrial mammals worldwide.

    PubMed

    Kissling, Wilm Daniel; Dalby, Lars; Fløjgaard, Camilla; Lenoir, Jonathan; Sandel, Brody; Sandom, Christopher; Trøjelsgaard, Kristian; Svenning, Jens-Christian

    2014-07-01

    Ecological trait data are essential for understanding the broad-scale distribution of biodiversity and its response to global change. For animals, diet represents a fundamental aspect of species' evolutionary adaptations, ecological and functional roles, and trophic interactions. However, the importance of diet for macroevolutionary and macroecological dynamics remains little explored, partly because of the lack of comprehensive trait datasets. We compiled and evaluated a comprehensive global dataset of diet preferences of mammals ("MammalDIET"). Diet information was digitized from two global and cladewide data sources and errors of data entry by multiple data recorders were assessed. We then developed a hierarchical extrapolation procedure to fill-in diet information for species with missing information. Missing data were extrapolated with information from other taxonomic levels (genus, other species within the same genus, or family) and this extrapolation was subsequently validated both internally (with a jack-knife approach applied to the compiled species-level diet data) and externally (using independent species-level diet information from a comprehensive continentwide data source). Finally, we grouped mammal species into trophic levels and dietary guilds, and their species richness as well as their proportion of total richness were mapped at a global scale for those diet categories with good validation results. The success rate of correctly digitizing data was 94%, indicating that the consistency in data entry among multiple recorders was high. Data sources provided species-level diet information for a total of 2033 species (38% of all 5364 terrestrial mammal species, based on the IUCN taxonomy). For the remaining 3331 species, diet information was mostly extrapolated from genus-level diet information (48% of all terrestrial mammal species), and only rarely from other species within the same genus (6%) or from family level (8%). Internal and external

  14. Distribution and ecology of small mammals in Albania.

    PubMed

    Rogozi, Elton; Bego, Ferdinand; Papa, Anna; Mersini, Kujtim; Bino, Silvia

    2013-01-01

    In order to gain an insight into the population dynamics and habitat preferences of rodents in Albania, small mammals were collected during 2006-2009 in various districts of the country. Of the 15 species of small mammals captured (12 in Rodentia and 3 in Insectivora order), the yellow-necked mouse (Apodemus flavicollis) was the most frequently collected, representing 50% of the 325 small mammals captured, followed by the wood mouse (Apodemus sylvaticus) (20.62%). Apodemus flavicollis is the primary reservoir for Dobrava-Belgrade virus which causes to humans hemorrhagic fever with renal syndrome; the places with A. flavicollis abundance were those with records of the human disease. Knowledge of the reservoir ecology in a country facilitates risk assessments for rodent-borne diseases.

  15. Skin diseases of rodents and small exotic mammals.

    PubMed

    Ellis, C; Mori, M

    2001-05-01

    Small exotic mammals and rodents are becoming popular pets in the United States. Like most other exotics, the popularity of these animals has vastly preceded the accumulation of practical husbandry and veterinary information available about them. Several dermatologic conditions have been described in most rodents and small exotic mammals; however, the practitioner can assume that more exist that have not yet been diagnosed or documented. It is not unreasonable to assume that rodents and small exotic mammals could be affected by many of the same dermatologic conditions well described in other animals. Veterinarians are encouraged always to apply the same diagnostic protocols used to work up skin problems in dogs and cats when presented with an exotic pet with a dermatologic disease.

  16. Establishing macroecological trait datasets: digitalization, extrapolation, and validation of diet preferences in terrestrial mammals worldwide

    PubMed Central

    Kissling, Wilm Daniel; Dalby, Lars; Fløjgaard, Camilla; Lenoir, Jonathan; Sandel, Brody; Sandom, Christopher; Trøjelsgaard, Kristian; Svenning, Jens-Christian

    2014-01-01

    Ecological trait data are essential for understanding the broad-scale distribution of biodiversity and its response to global change. For animals, diet represents a fundamental aspect of species’ evolutionary adaptations, ecological and functional roles, and trophic interactions. However, the importance of diet for macroevolutionary and macroecological dynamics remains little explored, partly because of the lack of comprehensive trait datasets. We compiled and evaluated a comprehensive global dataset of diet preferences of mammals (“MammalDIET”). Diet information was digitized from two global and cladewide data sources and errors of data entry by multiple data recorders were assessed. We then developed a hierarchical extrapolation procedure to fill-in diet information for species with missing information. Missing data were extrapolated with information from other taxonomic levels (genus, other species within the same genus, or family) and this extrapolation was subsequently validated both internally (with a jack-knife approach applied to the compiled species-level diet data) and externally (using independent species-level diet information from a comprehensive continentwide data source). Finally, we grouped mammal species into trophic levels and dietary guilds, and their species richness as well as their proportion of total richness were mapped at a global scale for those diet categories with good validation results. The success rate of correctly digitizing data was 94%, indicating that the consistency in data entry among multiple recorders was high. Data sources provided species-level diet information for a total of 2033 species (38% of all 5364 terrestrial mammal species, based on the IUCN taxonomy). For the remaining 3331 species, diet information was mostly extrapolated from genus-level diet information (48% of all terrestrial mammal species), and only rarely from other species within the same genus (6%) or from family level (8%). Internal and external

  17. Training birds and small mammals for medical behaviors.

    PubMed

    Mattison, Sara

    2012-09-01

    The use of operant conditioning in a zoologic setting allows zookeepers and other animal caretakers to train birds and small mammals to participate willingly in medical procedures. By using operant conditioning with an emphasis on positive reinforcement, small mammals and birds can be trained to cooperate in their own medical care in many ways. This conditioning can reduce stress for animals, caretakers, and veterinarians as well as reduce the potential for animal injuries. This article includes case studies of what the author has identified as foundation behaviors, intermediate behaviors, and advanced behaviors and the methods used to train them.

  18. Small mammals of a bitterbrush-cheatgrass community

    SciTech Connect

    Gano, K.A.; Rickard, W.H.

    1982-01-01

    Small mammals were live-trapped in burned and unburned segments of a bitterbrush-cheatgrass community during the years 1974-1979. Results indicate that the shrub-dominated unburned area supports about three times as many small mammals as the cheatgrass-dominated burned area. Species composition was similar in both areas with the exception of one ground squirrel (Spermophilus townsendii) captured on the unburned area. Other species caught were the Great Basin pocket mouse (Perognathus parvus), deer mouse (Peromyscus maniculatus), northern grasshopper mouse (Onychomys leucogaster), and the western harvest mouse (Reithrodontomys megalotis).

  19. Interactions between terrestrial mammals and the fruits of two neotropical rainforest tree species

    NASA Astrophysics Data System (ADS)

    Camargo-Sanabria, Angela A.; Mendoza, Eduardo

    2016-05-01

    Mammalian frugivory is a distinctive biotic interaction of tropical forests; however, most efforts in the Neotropics have focused on cases of animals foraging in the forest canopy, in particular primates and bats. In contrast much less is known about this interaction when it involves fruits deposited on the forest floor and terrestrial mammals. We conducted a camera-trapping survey to analyze the characteristics of the mammalian ensembles visiting fruits of Licania platypus and Pouteria sapota deposited on the forest floor in a well preserved tropical rainforest of Mexico. Both tree species produce large fruits but contrast in their population densities and fruit chemical composition. In particular, we expected that more species of terrestrial mammals would consume P. sapota fruits due to its higher pulp:seed ratio, lower availability and greater carbohydrate content. We monitored fruits at the base of 13 trees (P. sapota, n = 4 and L. platypus, n = 9) using camera-traps. We recorded 13 mammal species from which we had evidence of 8 consuming or removing fruits. These eight species accounted for 70% of the species of mammalian frugivores active in the forest floor of our study area. The ensemble of frugivores associated with L. platypus (6 spp.) was a subset of that associated with P. sapota (8 spp). Large body-sized species such as Tapirus bairdii, Pecari tajacu and Cuniculus paca were the mammals more frequently interacting with fruits of the focal species. Our results further our understanding of the characteristics of the interaction between terrestrial mammalian frugivores and large-sized fruits, helping to gain a more balanced view of its importance across different tropical forests and providing a baseline to compare against defaunated forests.

  20. Small mammals from Sima de los Huesos.

    PubMed

    Cuenca-Bescós, G; Laplana Conesa, C; Canudo, J I; Arsuaga, J L

    1997-01-01

    A small collection of rodents from Sima de los Huesos helps to clarify the stratigraphic position of this famous human locality. The presence of Allocricetus bursae and Pliomys lenki relictus and the size of A. bursae, Apodemus sylvaticus and Eliomys quercinus suggest a Middle Pleistocene age (Saalian) to the Clays where humans have been found.

  1. Helminth parasites of small mammals in Kerman province, southeastern Iran.

    PubMed

    Fasihi Harandi, Majid; Madjdzadeh, Seyed Massoud; Ahmadinejad, Mohammad

    2016-03-01

    Fifty-one specimens of small mammals were collected from different locations of Kerman province, southeastern Iran during 2007 and 2009. They constitute six species of rodents (Meriones persicus, Meriones libycus, Tatera indica, Dryomys nitedula and Mus musculus), one species of Erinaceomorpha (Paraechinus hypomelas) and one species of hare (Lepus europeus). The rate of helminthic infection was 45.1 % among all trapped specimens. In 28 out of 51 hunted specimens no intestinal helminth parasite was found. Of all mammals examined, 15 (29.4 %) had nematodes, 5 (9.8 %) had cestodes, and 3 (5.9 %) were infected with Acanthocephala. Five different species of parasites were isolated: Trichuris muris, Moniliformis moniliformis, Hymenolepis diminuta, Hymenolepis nana, and Mastophorus muris. Results of the present study indicate the potential of small mammals in the transmission of zoonotic helminthic infection.

  2. A method of approximating range size of small mammals

    USGS Publications Warehouse

    Stickel, L.F.

    1965-01-01

    In summary, trap success trends appear to provide a useful approximation to range size of easily trapped small mammals such as Peromyscus. The scale of measurement can be adjusted as desired. Further explorations of the usefulness of the plan should be made and modifications possibly developed before adoption.

  3. Small mammal herbivory: Feedbacks that help maintain desertified ecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We tested the hypothesis that herbivores contribute to feedbacks maintaining arid ecosystems in a degraded state. We studied small mammal herbivory on a subshrub, broom snakeweed (Gutierrezia sarothrae), and perennial grasses at three sites: (1) ungrazed black grama (Bouteloua eriopoda) grassland; (...

  4. Examining the Prey Mass of Terrestrial and Aquatic Carnivorous Mammals: Minimum, Maximum and Range

    PubMed Central

    Tucker, Marlee A.; Rogers, Tracey L.

    2014-01-01

    Predator-prey body mass relationships are a vital part of food webs across ecosystems and provide key information for predicting the susceptibility of carnivore populations to extinction. Despite this, there has been limited research on the minimum and maximum prey size of mammalian carnivores. Without information on large-scale patterns of prey mass, we limit our understanding of predation pressure, trophic cascades and susceptibility of carnivores to decreasing prey populations. The majority of studies that examine predator-prey body mass relationships focus on either a single or a subset of mammalian species, which limits the strength of our models as well as their broader application. We examine the relationship between predator body mass and the minimum, maximum and range of their prey's body mass across 108 mammalian carnivores, from weasels to baleen whales (Carnivora and Cetacea). We test whether mammals show a positive relationship between prey and predator body mass, as in reptiles and birds, as well as examine how environment (aquatic and terrestrial) and phylogenetic relatedness play a role in this relationship. We found that phylogenetic relatedness is a strong driver of predator-prey mass patterns in carnivorous mammals and accounts for a higher proportion of variance compared with the biological drivers of body mass and environment. We show a positive predator-prey body mass pattern for terrestrial mammals as found in reptiles and birds, but no relationship for aquatic mammals. Our results will benefit our understanding of trophic interactions, the susceptibility of carnivores to population declines and the role of carnivores within ecosystems. PMID:25162695

  5. Examining the prey mass of terrestrial and aquatic carnivorous mammals: minimum, maximum and range.

    PubMed

    Tucker, Marlee A; Rogers, Tracey L

    2014-01-01

    Predator-prey body mass relationships are a vital part of food webs across ecosystems and provide key information for predicting the susceptibility of carnivore populations to extinction. Despite this, there has been limited research on the minimum and maximum prey size of mammalian carnivores. Without information on large-scale patterns of prey mass, we limit our understanding of predation pressure, trophic cascades and susceptibility of carnivores to decreasing prey populations. The majority of studies that examine predator-prey body mass relationships focus on either a single or a subset of mammalian species, which limits the strength of our models as well as their broader application. We examine the relationship between predator body mass and the minimum, maximum and range of their prey's body mass across 108 mammalian carnivores, from weasels to baleen whales (Carnivora and Cetacea). We test whether mammals show a positive relationship between prey and predator body mass, as in reptiles and birds, as well as examine how environment (aquatic and terrestrial) and phylogenetic relatedness play a role in this relationship. We found that phylogenetic relatedness is a strong driver of predator-prey mass patterns in carnivorous mammals and accounts for a higher proportion of variance compared with the biological drivers of body mass and environment. We show a positive predator-prey body mass pattern for terrestrial mammals as found in reptiles and birds, but no relationship for aquatic mammals. Our results will benefit our understanding of trophic interactions, the susceptibility of carnivores to population declines and the role of carnivores within ecosystems.

  6. Isotope analyses of fossil small mammals in karstic sites

    NASA Astrophysics Data System (ADS)

    Garcia Alix, Antonio; Delgado Huertas, Antonio

    2016-04-01

    Fossil skeletal accumulations in kartstic complexes, such as caves, are quite common, especially during the Pliocene and Quaternary. These fossil assemblages are sometimes difficult to study, as specimens from different ages can be found together (time averaging). The traditional approach to study this kind of paleontological sites was taphonomic (understanding the origin and other factors affecting the bone accumulation) and/or taxonomic (systematic description of the remains). However, other kinds of analyses, such as biogeochemical techniques to reconstruct past diets and environments, are being more frequently used. Small-mammals have a wide geographical distribution, and their remains (bones and teeth) are extensively represented in the fossil record; therefore, isotopic analyses in fossil small-mammals are a powerful tool to reconstruct paleoenvironments. Field samples for small-mammal studies yield large amounts of sediment-residues that need to be reduced in the laboratory (usually by means of diluted hydrochloric or acetic acid). Therefore, samples of fossil small-mammal for isotopic analyses usually receive two different acid treatments: one to reduce the carbonate residue of the sediment, and afterwards another one to remove digenetic carbonates from the ground sample. Those treatments, along with the small size of the remains, may increase the probability of chemical fractionation during those pre-treatment stages. Those acid treatments are even more aggressive in kasrtic fossil localities, as limestone has to be dissolved to extract the small mammal remains. In this abstract, we present the results of two different treatments carried out in limestone from the Pliocene karstic locality of Moreda (Guadix Basin, Spain) and a control sample. One batch of samples were treated with a solution of 1M acetic acid-acetate calcium buffer (ph 4,5), and the rest with diluted acetic acid (at 15% concentration, Ph 2,2), which is the most used to reduce the sediments

  7. Effectiveness of Protected Areas for Representing Species and Populations of Terrestrial Mammals in Costa Rica

    PubMed Central

    González-Maya, José F.; Víquez-R, Luis R.; Belant, Jerrold L.; Ceballos, Gerardo

    2015-01-01

    Costa Rica has one of the greatest percentages (26%) of protected land in the world. The National Protected Areas System (NPAS) of Costa Rica was established in 1976 and currently includes >190 protected areas within seven different protection categories. The effectiveness of the NPAS to represent species, populations, and areas with high species richness has not been properly evaluated. Such evaluations are fundamental to understand what is necessary to strengthen the NPAS and better protect biodiversity. We present a novel assessment of NPAS effectiveness in protecting mammal species. We compiled the geographical ranges of all terrestrial Costa Rican mammals then determined species lists for all protected areas and the estimated proportion of each species’ geographic range protected. We also classified mammal species according to their conservation status using the IUCN Red List of Threatened Species. We found almost complete representation of mammal species (98.5%) in protected areas, but low relative coverage (28.3% on average) of their geographic ranges in Costa Rica and 25% of the species were classified as underprotected according to a priori representation targets. Interestingly, many species-rich areas are not protected, and at least 43% of cells covering the entire country are not included in protected areas. Though protected areas in Costa Rica represent species richness well, strategic planning for future protected areas to improve species complementarity and range protection is necessary. Our results can help to define sites where new protected areas can have a greater impact on mammal conservation, both in terms of species richness and range protection. PMID:25970293

  8. Butyltin residues in livers of humans and wild terrestrial mammals and in plastic products.

    PubMed

    Takahashi, S; Mukai, H; Tanabe, S; Sakayama, K; Miyazaki, T; Masuno, H

    1999-08-01

    Butyltin compounds (BTs) including mono-(MBT), di-(DBT) and tributyltin (TBT) were determined in livers of humans and wild terrestrial mammals, such as raccoon dogs (Nyctereutes procyonoids) and monkeys (Macaca fuscata) from Japan. In addition, 22 samples of plastic products were analyzed. BT residues were detected in all the liver samples of humans and raccoon dogs, with concentrations of <360 ng/g wet wt, whereas concentrations in the liver of monkeys were either less than the detection limit or were only in trace levels. Elevated concentrations of BTs, particularly DBT (<140,000 ng/g) and MBT (<130,000 ng/g), were found in some plastic products, such as baking parchments made from siliconized paper and gloves made up from polyurethane. The results of a cooking test using the above baking parchment indicated the transfer of BTs to foodstuffs. These observations suggest expansion of BT contamination among terrestrial mammals. BT pollution from industrial appliances, such as plastic stabilizers and catalysts other than those of marine origin as antifouling agents, are suggested as alternative sources of exposure.

  9. Detection of diverse novel astroviruses from small mammals in China.

    PubMed

    Hu, Ben; Chmura, Aleksei A; Li, Jialu; Zhu, Guangjian; Desmond, James S; Zhang, Yunzhi; Zhang, Wei; Epstein, Jonathan H; Daszak, Peter; Shi, Zhengli

    2014-11-01

    Astroviruses infect humans and many animal species and cause gastroenteritis. To extensively understand the distribution and genetic diversity of astrovirus in small mammals, we tested 968 anal swabs from 39 animal species, most of which were bats and rodents. We detected diverse astroviruses in 10 bat species, including known bat astroviruses and a large number of novel viruses. Meanwhile, novel groups of astroviruses were identified in three wild rodent species and a remarkably high genetic diversity of astrovirus was revealed in Eothenomys cachinus. We detected astroviruses in captive-bred porcupines and a nearly full-length genome sequence was determined for one strain. Phylogenetic analysis of the complete ORF2 sequence suggested that this strain may share a common ancestor with porcine astrovirus type 2. Moreover, to our knowledge, this study reports the first discovery of astroviruses in shrews and pikas. Our results provide new insights for understanding these small mammals as natural reservoirs of astroviruses.

  10. Estimation methodology in contemporary small mammal capture-recapture studies

    USGS Publications Warehouse

    Nichols, J.D.; Pollock, K.H.

    1983-01-01

    Estimators of population size and survival rate based on the Jolly-Seber capture-recapture model and the 'enumeration method' are described. Enumeration estimators are shown to estimate complicated functions of capture and survival probabilities and, in the case of the population size estimator, population size. Frequently-listed reasons for preferring enumeration estimators are discussed and the Jolly-Seber estimators are shown to be superior even in the case of heterogeneity and trap-happy response, the two sources of unequal capture probability most likely to occur in small mammal studies. New developments in probabilistic capture-recapture models are described, and these models are recommended for future small mammal capture-recapture studies.

  11. The future of terrestrial mammals in the Mediterranean basin under climate change

    PubMed Central

    Maiorano, Luigi; Falcucci, Alessandra; Zimmermann, Niklaus E.; Psomas, Achilleas; Pottier, Julien; Baisero, Daniele; Rondinini, Carlo; Guisan, Antoine; Boitani, Luigi

    2011-01-01

    The Mediterranean basin is considered a hotspot of biological diversity with a long history of modification of natural ecosystems by human activities, and is one of the regions that will face extensive changes in climate. For 181 terrestrial mammals (68% of all Mediterranean mammals), we used an ensemble forecasting approach to model the future (approx. 2100) potential distribution under climate change considering five climate change model outputs for two climate scenarios. Overall, a substantial number of Mediterranean mammals will be severely threatened by future climate change, particularly endemic species. Moreover, we found important changes in potential species richness owing to climate change, with some areas (e.g. montane region in central Italy) gaining species, while most of the region will be losing species (mainly Spain and North Africa). Existing protected areas (PAs) will probably be strongly influenced by climate change, with most PAs in Africa, the Middle East and Spain losing a substantial number of species, and those PAs gaining species (e.g. central Italy and southern France) will experience a substantial shift in species composition. PMID:21844047

  12. Geographical Gradients in Argentinean Terrestrial Mammal Species Richness and Their Environmental Correlates

    PubMed Central

    Márquez, Ana L.; Real, Raimundo; Kin, Marta S.; Guerrero, José Carlos; Galván, Betina; Barbosa, A. Márcia; Olivero, Jesús; Palomo, L. Javier; Vargas, J. Mario; Justo, Enrique

    2012-01-01

    We analysed the main geographical trends of terrestrial mammal species richness (SR) in Argentina, assessing how broad-scale environmental variation (defined by climatic and topographic variables) and the spatial form of the country (defined by spatial filters based on spatial eigenvector mapping (SEVM)) influence the kinds and the numbers of mammal species along these geographical trends. We also evaluated if there are pure geographical trends not accounted for by the environmental or spatial factors. The environmental variables and spatial filters that simultaneously correlated with the geographical variables and SR were considered potential causes of the geographic trends. We performed partial correlations between SR and the geographical variables, maintaining the selected explanatory variables statistically constant, to determine if SR was fully explained by them or if a significant residual geographic pattern remained. All groups and subgroups presented a latitudinal gradient not attributable to the spatial form of the country. Most of these trends were not explained by climate. We used a variation partitioning procedure to quantify the pure geographic trend (PGT) that remained unaccounted for. The PGT was larger for latitudinal than for longitudinal gradients. This suggests that historical or purely geographical causes may also be relevant drivers of these geographical gradients in mammal diversity. PMID:23028254

  13. Corridors and olfactory predator cues affect small mammal behavior.

    SciTech Connect

    Brinkerhoff, Robert Jory; Haddad, Nick M.; Orrock, John L.

    2005-03-30

    Abstract The behavior of prey individuals is influenced by a variety of factors including, but not limited to, habitat configuration, risk of predation, and availability of resources, and these habitat-dependent factors may have interactive effects. We studied the responses of mice to an increase in perceived predation risk in a patchy environment to understand how habitat corridors might affect interactions among species in a fragmented landscape. We used a replicated experiment to investigate corridor-mediated prey responses to predator cues in a network of open habitat patches surrounded by a matrix of planted pine forest. Some of the patches were connected by corridors. We used mark–recapture techniques and foraging trays to monitor the movement, behavior, and abundance of small mammals. Predation threat was manipulated in one-half of the replicates by applying an olfactory predator cue. Corridors synchronized small mammal foraging activity among connected patches. Foraging also was inhibited in the presence of an olfactory predator cue but apparently increased in adjacent connected patches. Small mammal abundance did not change as a result of the predator manipulation and was not influenced by the presence of corridors. This study is among the 1st to indicate combined effects of landscape configuration and predation risk on prey behavior. These changes in prey behavior may, in turn, have cascading effects on community dynamics where corridors and differential predation risk influence movement and patch use.

  14. Bartonella infection in sylvatic small mammals of central Sweden.

    PubMed Central

    Holmberg, M.; Mills, J. N.; McGill, S.; Benjamin, G.; Ellis, B. A.

    2003-01-01

    Sylvatic small mammals were captured in rural habitats near Uppsala, Sweden, to measure the prevalence of bartonella infections, characterize bacterial isolates and identify their host range, and increase our understanding of host-pathogen ecology. During 7 nights of trapping at 3 localities, 236 small mammals were captured (trap success 30%). Bartonella were isolated from bloods of Apodemus flavicollis (19 of 110 tested), Apodemus sylvaticus (6/25), Clethrionomys glareolus (9/60), Microtus agrestis (1/3), Mus musculus (1/18), and Sorex araneus (3/20). Nucleotide sequencing (a 338 bp fragment of the gltA gene) of 40 isolates yielded 6 unique genotypes. Five of the 6 genotypes were most similar to other known bartonella isolated from Old World small-mammal hosts. The most frequent genotype (83%) was isolated from A. flavicollis and M. musculus and was identical to Bartonella grahamii, a recently demonstrated human pathogen. These two hosts were most frequently captured in and around human structures and work places, thus providing conditions that could potentially lead to frequent human infections. PMID:12613756

  15. Small mammal response to the introduction of cattle into a cottonwood floodplain

    USGS Publications Warehouse

    Samson, F.B.; Knopf, F.L.; Hass, L.B.

    1988-01-01

    Few differences between pastures in small mammal communities were evident prior to grazing, 1 month following grazing, and no differences in number or distribution of small mammals were observed 5 months following grazing. Each small mammal species exhibited different habitat use compared to availability and few habitat variables differed on grazed versus ungrazed pastures. Grazing at SCS recommendations in winter did not appear to have an initial effect on small mammal populations or their habitats in a Colorado floodplain.

  16. Comparative dynamics of small mammal populations in treefall gaps and surrounding understorey within Amazonian rainforest

    USGS Publications Warehouse

    Beck, H.; Gaines, M.S.; Hines, J.E.; Nichols, J.D.

    2004-01-01

    Variation in food resource availability can have profound effects on habitat selection and dynamics of populations. Previous studies reported higher food resource availability and fruit removal in treefall gaps than in the understorey. Therefore, gaps have been considered 'keystone habitat' for Neotropical frugivore birds. Here we test if this prediction would also hold for terrestrial small mammals. In the Amazon, we quantified food resource availability in eleven treefall gaps and paired understorey habitats and used feeding experiments to test if two common terrestrial rodents (Oryzomys megacephalus and Proechimys spp.) would perceive differences between habitats. We live-trapped small mammals in eleven gaps and understorey sites for two years, and compared abundance, fitness components (survival and per capita recruitment) and dispersal of these two rodent species across gaps and understorey and seasons (rainy and dry). Our data indicated no differences in resource availability and consumption rate between habitats. Treefall gaps may represent a sink habitat for Oryzomys where individuals had lower fitness, apparently because of habitat-specific ant predation on early life stages, than in the understorey, the source habitat. Conversely, gaps may be source habitat for Proechimys where individuals had higher fitness, than in the understorey, the sink habitat. Our results suggest the presence of source-sink dynamics in a tropical gap-understorey landscape, where two rodent species perceive habitats differently. This may be a mechanism for their coexistence in a heterogeneous and species-diverse system.

  17. Radionuclide transfer to invertebrates and small mammals in a coastal sand dune ecosystem.

    PubMed

    Wood, M D; Leah, R T; Jones, S R; Copplestone, D

    2009-06-15

    International intercomparisons of models to assess the impact of ionising radiation on wildlife have identified radionuclide transfer assumptions as a significant source of uncertainty in the modelling process. There is a need to improve the underpinning data sets on radionuclide transfer to reduce this uncertainty, especially for poorly-studied ecosystems such as coastal sand dunes. This paper presents the results of the first published study of radionuclide transfer to invertebrates and small mammals in a coastal sand dune ecosystem. Activity concentrations of (137)Cs, (238)Pu, (239+240)Pu and (241)Am are reported for detritivorous, herbivorous, carnivorous and omnivorous biota. Differences in activity concentrations measured in the sand dune biota are related to the trophic level of the organisms and the influence of sea-to-land transfer is apparent in the food chain transfer observed at the site. There are notable differences in the concentration ratios (CRs) calculated for the sand dune biota compared to other terrestrial ecosystems, especially for the small mammals which have CRs that are two orders of magnitude lower than the generic terrestrial ecosystem CRs published by the recent EC EURATOM ERICA project. The lower CRs at the sand dunes may be due to the influence of other cations from the marine environment (e.g. K and Na) on the net radionuclide transfer observed, but further research is required to test this hypothesis.

  18. Taphonomy for taxonomists: Implications of predation in small mammal studies

    NASA Astrophysics Data System (ADS)

    Fernández-Jalvo, Yolanda; Andrews, Peter; Denys, Christiane; Sesé, Carmen; Stoetzel, Emmanuelle; Marin-Monfort, Dolores; Pesquero, Dolores

    2016-05-01

    Predation is one of the most recurrent sources of bone accumulations. The influence of predation is widely studied for large mammal sites where humans, acting as predators, produce bone accumulations similar to carnivore accumulations. Similarly, small mammal fossil sites are mainly occupation levels of predators (nests or dens). In both cases, investigations of past events can be compared with present day equivalents or proxies. Chewing marks are sometimes present on large mammal predator accumulations, but digestion traits are the most direct indication of predation, and evidence for this is always present in small mammal (prey) fossil assemblages. Digestion grades and frequency indicates predator type and this is well established since the publication of Andrews (1990). The identification of the predator provides invaluable information for accurate interpretation of the palaeoenvironment. Traditionally, palaeoenvironmental interpretations are obtained from the taxonomic species identified in the site, but rather than providing direct interpretations of the surrounding palaeoenvironment, this procedure actually describes the dietary preferences of the predators and the type of occupation (nests, marking territory, dens, etc). This paper reviews the identification of traits produced by predators on arvicolins, murins and soricids using a method that may be used equally by taxonomists and taphonomists. It aims to provide the "tools" for taxonomists to identify the predator based on their methodology, which is examining the occlusal surfaces of teeth rather than their lateral aspects. This will greatly benefit both the work of taphonomists and taxonomists to recognize signs of predation and the improvement of subsequent palaeoecological interpretations of past organisms and sites by identifying both the prey and the predator.

  19. Natural population die-offs: causes and consequences for terrestrial mammals.

    PubMed

    Ameca Y Juárez, Eric I; Mace, Georgina M; Cowlishaw, Guy; Pettorelli, Nathalie

    2012-05-01

    Extreme changes in the environment can generate high mortalities in wildlife populations. When these mortalities are attributable to extreme natural events, they are referred to as natural population die-offs. Despite growing reports of such die-offs, a consensus on how to define them has not emerged. Furthermore, although anthropogenically caused extreme events are predicted to occur at a higher frequency and intensity compared with natural events, an integrative synthesis assessing their significance for wildlife population viability is lacking. These issues hamper the ability to identify populations most at risk. Here, we propose a functional definition of natural population die-offs, an assessment of extrinsic and intrinsic processes shaping these die-offs, and a framework for assessing the vulnerability of terrestrial mammals to natural and anthropogenically caused extreme events.

  20. Pinniped tuberculosis in Malayan tapirs (Tapirus indicus) and its transmission to other terrestrial mammals.

    PubMed

    Jurczynski, Kerstin; Lyashchenko, Konstantin P; Gomis, David; Moser, Irmgard; Greenwald, Rena; Moisson, Pierre

    2011-06-01

    In the last 7 yr, three different species of terrestrial mammals were diagnosed with Mycobacterium pinnipedii either within one collection or through the introduction of an infected animal from another zoo. The affected species included the Malayan tapir (Tapirus indicus), Bactrian camel (Camelus bactrianus bactrianus), and crested porcupine (Hystrix cristata). In the first zoo, all of these were living in exhibits adjacent to a group of South American sea lions (Otariaflavescens) and were cared for by the same keeper. One infected tapir was transferred to a different zoo and transmitted M. pinnipedii infection to three other Malayan tapirs. The tapirs were tested with various diagnostic methods, including comparative intradermal tuberculin test, PCR and culture of sputum samples, Rapid Test (RT), and multiantigen print immunoassay (MAPIA). The M. pinnipedii infection was confirmed at postmortem examination in all animals. RT and MAPIA showed the diagnostic potential for rapid antemortem detection of this important zoonotic disease.

  1. Impacts of the Cretaceous Terrestrial Revolution and KPg extinction on mammal diversification.

    PubMed

    Meredith, Robert W; Janečka, Jan E; Gatesy, John; Ryder, Oliver A; Fisher, Colleen A; Teeling, Emma C; Goodbla, Alisha; Eizirik, Eduardo; Simão, Taiz L L; Stadler, Tanja; Rabosky, Daniel L; Honeycutt, Rodney L; Flynn, John J; Ingram, Colleen M; Steiner, Cynthia; Williams, Tiffani L; Robinson, Terence J; Burk-Herrick, Angela; Westerman, Michael; Ayoub, Nadia A; Springer, Mark S; Murphy, William J

    2011-10-28

    Previous analyses of relations, divergence times, and diversification patterns among extant mammalian families have relied on supertree methods and local molecular clocks. We constructed a molecular supermatrix for mammalian families and analyzed these data with likelihood-based methods and relaxed molecular clocks. Phylogenetic analyses resulted in a robust phylogeny with better resolution than phylogenies from supertree methods. Relaxed clock analyses support the long-fuse model of diversification and highlight the importance of including multiple fossil calibrations that are spread across the tree. Molecular time trees and diversification analyses suggest important roles for the Cretaceous Terrestrial Revolution and Cretaceous-Paleogene (KPg) mass extinction in opening up ecospace that promoted interordinal and intraordinal diversification, respectively. By contrast, diversification analyses provide no support for the hypothesis concerning the delayed rise of present-day mammals during the Eocene Period.

  2. Evolutionary origins of hepatitis A virus in small mammals.

    PubMed

    Drexler, Jan Felix; Corman, Victor M; Lukashev, Alexander N; van den Brand, Judith M A; Gmyl, Anatoly P; Brünink, Sebastian; Rasche, Andrea; Seggewiβ, Nicole; Feng, Hui; Leijten, Lonneke M; Vallo, Peter; Kuiken, Thijs; Dotzauer, Andreas; Ulrich, Rainer G; Lemon, Stanley M; Drosten, Christian

    2015-12-08

    Hepatitis A virus (HAV) is an ancient and ubiquitous human pathogen recovered previously only from primates. The sole species of the genus Hepatovirus, existing in both enveloped and nonenveloped forms, and with a capsid structure intermediate between that of insect viruses and mammalian picornaviruses, HAV is enigmatic in its origins. We conducted a targeted search for hepatoviruses in 15,987 specimens collected from 209 small mammal species globally and discovered highly diversified viruses in bats, rodents, hedgehogs, and shrews, which by pairwise sequence distance comprise 13 novel Hepatovirus species. Near-complete genomes from nine of these species show conservation of unique hepatovirus features, including predicted internal ribosome entry site structure, a truncated VP4 capsid protein lacking N-terminal myristoylation, a carboxyl-terminal pX extension of VP1, VP2 late domains involved in membrane envelopment, and a cis-acting replication element within the 3D(pol) sequence. Antibodies in some bat sera immunoprecipitated and neutralized human HAV, suggesting conservation of critical antigenic determinants. Limited phylogenetic cosegregation among hepatoviruses and their hosts and recombination patterns are indicative of major hepatovirus host shifts in the past. Ancestral state reconstructions suggest a Hepatovirus origin in small insectivorous mammals and a rodent origin of human HAV. Patterns of infection in small mammals mimicked those of human HAV in hepatotropism, fecal shedding, acute nature, and extinction of the virus in a closed host population. The evolutionary conservation of hepatovirus structure and pathogenesis provide novel insight into the origins of HAV and highlight the utility of analyzing animal reservoirs for risk assessment of emerging viruses.

  3. Evolutionary origins of hepatitis A virus in small mammals

    PubMed Central

    Drexler, Jan Felix; Corman, Victor M.; Lukashev, Alexander N.; van den Brand, Judith M. A.; Gmyl, Anatoly P.; Brünink, Sebastian; Rasche, Andrea; Seggewiβ, Nicole; Feng, Hui; Leijten, Lonneke M.; Vallo, Peter; Kuiken, Thijs; Dotzauer, Andreas; Ulrich, Rainer G.; Lemon, Stanley M.; Drosten, Christian

    2015-01-01

    Hepatitis A virus (HAV) is an ancient and ubiquitous human pathogen recovered previously only from primates. The sole species of the genus Hepatovirus, existing in both enveloped and nonenveloped forms, and with a capsid structure intermediate between that of insect viruses and mammalian picornaviruses, HAV is enigmatic in its origins. We conducted a targeted search for hepatoviruses in 15,987 specimens collected from 209 small mammal species globally and discovered highly diversified viruses in bats, rodents, hedgehogs, and shrews, which by pairwise sequence distance comprise 13 novel Hepatovirus species. Near-complete genomes from nine of these species show conservation of unique hepatovirus features, including predicted internal ribosome entry site structure, a truncated VP4 capsid protein lacking N-terminal myristoylation, a carboxyl-terminal pX extension of VP1, VP2 late domains involved in membrane envelopment, and a cis-acting replication element within the 3Dpol sequence. Antibodies in some bat sera immunoprecipitated and neutralized human HAV, suggesting conservation of critical antigenic determinants. Limited phylogenetic cosegregation among hepatoviruses and their hosts and recombination patterns are indicative of major hepatovirus host shifts in the past. Ancestral state reconstructions suggest a Hepatovirus origin in small insectivorous mammals and a rodent origin of human HAV. Patterns of infection in small mammals mimicked those of human HAV in hepatotropism, fecal shedding, acute nature, and extinction of the virus in a closed host population. The evolutionary conservation of hepatovirus structure and pathogenesis provide novel insight into the origins of HAV and highlight the utility of analyzing animal reservoirs for risk assessment of emerging viruses. PMID:26575627

  4. Small mammal study of Sandia Canyon, 1994 and 1995

    SciTech Connect

    Bennett, K.; Biggs, J.

    1996-11-01

    A wide range of plant and wildlife species utilize water discharged from facilities at Los Alamos National Laboratory (LANL). The purpose of this study was to gather baseline data of small mammal populations and compare small mammal characteristics within three areas of Sandia Canyon, which receives outfall effluents from multiple sources. Three small mammal trapping webs were placed in the upper portion of Sandia Canyon, the first two were centered in a cattail-dominated marsh with a ponderosa pine overstory and the third web was placed in a much drier transition area with a ponderosa pine overstory. Webs 1 and 2 had the highest species diversity indices with deer mice the most commonly captured species in all webs. However, at Web 1, voles, shrews, and harvest mice, species more commonly found in moist habitats, made up a much greater overall percentage (65.6%) than did deer mice and brush mice (34.5%). The highest densities and biomass of animals were found in Web 1 with a continual decrease in density estimates in each web downstream. There is no statistical difference between the mean body weights of deer mice and brush mice between sites. Mean body length was also determined not to be statistically different between the webs (GLM [deer mouse], F = 0.89, p = 0.4117; GLM [brush mouse], F = 2.49, p = 0.0999). Furthermore, no statistical difference between webs was found for the mean lean body masses of deer and brush mice (GLM [deer mouse], F = 2.54, p = 0.0838; GLM [brush mouse], F = 1.60, p = 0.2229). Additional monitoring studies should be conducted in Sandia Canyon so comparisons over time can be made. In addition, rodent tissues should be sampled for contaminants and then compared to background or control populations elsewhere at the Laboratory or at an off-site location.

  5. Small exotic companion mammal wellness management and environmental enrichment.

    PubMed

    Pilny, Anthony A

    2015-05-01

    Wellness management and environmental enrichment are important components of preventative veterinary medical care. Small exotic mammals represent a diverse group of pets with widely varying types of care, diet, and husbandry considerations; thus, environmental enrichment must go beyond the cage or tank design in order to provide proper mental fitness in meeting any pet's psychological needs. Addressing the pet's environmental, dietary, exercise, and social needs is vital to keeping these animals healthier and more disease resistant. The key to accomplishing this is largely impacted by the annual or biannual veterinary wellness visit and a commitment from the pet's owner.

  6. Measurements of uranium in soils and small mammals

    SciTech Connect

    Miera, F.R. Jr.

    1980-12-01

    The objective of this study was to evaluate the bioavailability of uranium to a single species of small mammal, Peromyscus maniculatus rufinus (Merriam), white-footed deer mouse, from two different source terms: a Los Alamos National Laboratory dynamic weapons testing site in north central New Mexico, where an estimated 70,000 kg of uranium have been expended over a 31-y period; and an inactive uranium mill tailings pile located in west central New Mexico near Grants, which received wastes over a 5-y period from the milling of 2.7 x 10/sup 9/ kg of uranium ore.

  7. Small mammal populations in a restored stream corridor

    SciTech Connect

    Wike, L.D.

    2000-03-13

    An opportunity to study the response of a small mammal community to restoration of a riparian wetland was provided by the Pen Branch project at the Savannah River Site (SRS). Live trapping of small mammals was conducted on six transects at Pen Branch in 1996 and 1998 and at three transects at Meyer's Branch, an unimpacted stream at SRS, in 1997 and 1998. Distributions of rates of capture of the four most common species were both spatially and temporally uneven. Kruskal-Wallis one-way analysis of variance found no significant differences in the relationship of capture rates between species and between treatment and both the within-stream control and Meyers Branch. Habitat use and movement within stream corridors appears to be dependent primarily on species, with age and sex perhaps contributing to preference and distance moved. The lack of differences in capture rates related to transect or treatment may be due to the close proximity of sample transects relative to the movement potential of the species sampled.

  8. The trap line as a measure of small mammal populations

    USGS Publications Warehouse

    Stickel, L.F.

    1948-01-01

    SUMMARY: The value of a line of traps as a measure of relative abundance of small mammals was studied by field trials on Peromyscus leucopus populations. Comparisons were made between the numbers of mice captured by a line of live traps and the numbers captured in intensive live trapping of a larger area surrounding the line. Trials were made in bottomland woods where mice were numerous and in upland woods where mice were less common. It was found that wood mice living in upland woods had significantly larger cruising ranges than those living in bottomland woods. Consequently, a line of traps in the bottomlands captured mice from a smaller surrounding territory than in the uplands. Therefore, comparisons of relative size of the mouse population in these two areas on the basis of line-trapping showed an erroneously large number for the upland woods. As a result of these trials and the studies of other workers, it is concluded that lines of traps are not fully reliable means of measuring relative abundance of small mammals.

  9. Towards biodiversity hotspots effective for conserving mammals with small geographic ranges

    NASA Astrophysics Data System (ADS)

    Carrara, Rodolfo; San Blas, Germán; Agrain, Federico; Roig-Juñent, Sergio

    2017-01-01

    The main goal of using global biodiversity hotspots for conservation purposes is to protect taxa with small geographic ranges because these are highly vulnerable to extinction. However, the extent to what different hotspots types are effective for meeting this goal remains controversial because hotspots have been previously defined as either the richest or most threatened and richest sites in terms of total, endemic or threatened species. In this regard, the use of species richness to set conservation priorities is widely discussed because strategies focused on this diversity measure tend to miss many of the taxa with small geographic ranges. Here we use data on global terrestrial mammal distributions to show that, hotspots of total species, endemism and threat defined in terms of species richness are effective in including 27%, 29% and 11% respectively, of the taxa with small geographic ranges. Whilst, the same hotspot types defined in terms of a simple diversity index, which is a function of species richness and range-size rarity, include 68%, 44% and 90% respectively, of these taxa. In addition, we demonstrate that index hotspot types are highly efficient because they conserve 79% of mammal species (21% more species than richness hotspot types), with 59% of species shared by three hotspot types (31% more than richness hotspot types). These results suggest that selection of different diversity measures to define hotspots may strongly affect the achievement of conservation goals.

  10. Population responses of small mammals to food supply and predators: a global meta-analysis.

    PubMed

    Prevedello, Jayme A; Dickman, Chris R; Vieira, Marcus V; Vieira, Emerson M

    2013-09-01

    1. The relative importance of food supply and predation as determinants of animal population density is a topic of enduring debate among ecologists. To address it, many studies have tested the potential effects of food on population density by experimentally supplementing natural populations, with much focus on terrestrial vertebrates, especially small mammals. 2. Here we perform a meta-analysis of such experiments, testing two complementary hypotheses: (i) small mammal populations are bottom-up limited and (ii) population increases in response to food supplementation are constrained by predation, a top-down limitation. 3. In the 148 experiments recorded, food supplementation had an overall positive and significant effect, increasing population densities by 1.5-fold. Larger population increases occurred when predation was reduced and populations were open to immigration. Predation appeared to be unimportant when populations were closed to immigration. Immigration was the major mechanism underlying increases in abundance by increasing local population density and crowding. Contributions of increased reproductive rate could be detected, but were minor compared to immigration, and no effects were detected from survival. 4. Our analyses support the view that animal population density is determined by both bottom-up and top-down forces. They also suggest the possibility that food supplementation experiments might unintentionally create ecological traps by aggregating both prey and predators in small areas of the landscape. We suggest an alternative experimental design to increase the contribution that food supplementation experiments can make in future.

  11. Evaluation of micro-GPS receivers for tracking small-bodied mammals

    PubMed Central

    Shipley, Lisa A.; Forbey, Jennifer S.; Olsoy, Peter J.

    2017-01-01

    GPS telemetry markedly enhances the temporal and spatial resolution of animal location data, and recent advances in micro-GPS receivers permit their deployment on small mammals. One such technological advance, snapshot technology, allows for improved battery life by reducing the time to first fix via postponing recovery of satellite ephemeris (satellite location) data and processing of locations. However, no previous work has employed snapshot technology for small, terrestrial mammals. We evaluated performance of two types of micro-GPS (< 20 g) receivers (traditional and snapshot) on a small, semi-fossorial lagomorph, the pygmy rabbit (Brachylagus idahoensis), to understand how GPS errors might influence fine-scale assessments of space use and habitat selection. During stationary tests, microtopography (i.e., burrows) and satellite geometry had the largest influence on GPS fix success rate (FSR) and location error (LE). There was no difference between FSR while animals wore the GPS collars above ground (determined via light sensors) and FSR generated during stationary, above-ground trials, suggesting that animal behavior other than burrowing did not markedly influence micro-GPS errors. In our study, traditional micro-GPS receivers demonstrated similar FSR and LE to snapshot receivers, however, snapshot receivers operated inconsistently due to battery and software failures. In contrast, the initial traditional receivers deployed on animals experienced some breakages, but a modified collar design consistently functioned as expected. If such problems were resolved, snapshot technology could reduce the tradeoff between fix interval and battery life that occurs with traditional micro-GPS receivers. Our results suggest that micro-GPS receivers are capable of addressing questions about space use and resource selection by small mammals, but that additional techniques might be needed to identify use of habitat structures (e.g., burrows, tree cavities, rock crevices) that

  12. Evaluation of micro-GPS receivers for tracking small-bodied mammals.

    PubMed

    McMahon, Laura A; Rachlow, Janet L; Shipley, Lisa A; Forbey, Jennifer S; Johnson, Timothy R; Olsoy, Peter J

    2017-01-01

    GPS telemetry markedly enhances the temporal and spatial resolution of animal location data, and recent advances in micro-GPS receivers permit their deployment on small mammals. One such technological advance, snapshot technology, allows for improved battery life by reducing the time to first fix via postponing recovery of satellite ephemeris (satellite location) data and processing of locations. However, no previous work has employed snapshot technology for small, terrestrial mammals. We evaluated performance of two types of micro-GPS (< 20 g) receivers (traditional and snapshot) on a small, semi-fossorial lagomorph, the pygmy rabbit (Brachylagus idahoensis), to understand how GPS errors might influence fine-scale assessments of space use and habitat selection. During stationary tests, microtopography (i.e., burrows) and satellite geometry had the largest influence on GPS fix success rate (FSR) and location error (LE). There was no difference between FSR while animals wore the GPS collars above ground (determined via light sensors) and FSR generated during stationary, above-ground trials, suggesting that animal behavior other than burrowing did not markedly influence micro-GPS errors. In our study, traditional micro-GPS receivers demonstrated similar FSR and LE to snapshot receivers, however, snapshot receivers operated inconsistently due to battery and software failures. In contrast, the initial traditional receivers deployed on animals experienced some breakages, but a modified collar design consistently functioned as expected. If such problems were resolved, snapshot technology could reduce the tradeoff between fix interval and battery life that occurs with traditional micro-GPS receivers. Our results suggest that micro-GPS receivers are capable of addressing questions about space use and resource selection by small mammals, but that additional techniques might be needed to identify use of habitat structures (e.g., burrows, tree cavities, rock crevices) that

  13. Fine-Scale Habitat Heterogeneity Influences Occupancy in Terrestrial Mammals in a Temperate Region of Australia.

    PubMed

    Stirnemann, Ingrid; Mortelliti, Alessio; Gibbons, Philip; Lindenmayer, David B

    2015-01-01

    Vegetation heterogeneity is an inherent feature of most ecosystems, characterises the structure of habitat, and is considered an important driver of species distribution patterns. However, quantifying fine-scale heterogeneity of vegetation cover can be time consuming, and therefore it is seldom measured. Here, we determine if heterogeneity is worthwhile measuring, in addition to the amount of cover, when examining species distribution patterns. Further, we investigated the effect of the surrounding landscape heterogeneity on species occupancy. We tested the effect of cover and heterogeneity of trees and shrubs, and the context of the surrounding landscape (number of habitats and distance to an ecotone) on site occupancy of three mammal species (the black wallaby [Wallabia bicolor], the long-nosed bandicoot [Perameles nasuta], and the bush rat [Rattus fuscipes]) within a naturally heterogeneous landscape in a temperate region of Australia. We found that fine-scale heterogeneity of vegetation attributes is an important driver of mammal occurrence of two of these species. Further, we found that, although all three species responded positively to vegetation heterogeneity, different mammals vary in their response to different types of vegetation heterogeneity measurement. For example, the black wallaby responded to the proximity of an ecotone, and the bush rat and the long-nosed bandicoot responded to fine-scale heterogeneity of small tree cover, whereas none of the mammals responded to broad scale heterogeneity (i.e., the number of habitat types). Our results highlight the influence of methodological decisions, such as how heterogeneity vegetation is measured, in quantifying species responses to habitat structures. The findings confirm the importance of choosing meaningful heterogeneity measures when modelling the factors influencing occupancy of the species of interest.

  14. Fine-Scale Habitat Heterogeneity Influences Occupancy in Terrestrial Mammals in a Temperate Region of Australia

    PubMed Central

    Stirnemann, Ingrid; Mortelliti, Alessio; Gibbons, Philip; Lindenmayer, David B.

    2015-01-01

    Vegetation heterogeneity is an inherent feature of most ecosystems, characterises the structure of habitat, and is considered an important driver of species distribution patterns. However, quantifying fine-scale heterogeneity of vegetation cover can be time consuming, and therefore it is seldom measured. Here, we determine if heterogeneity is worthwhile measuring, in addition to the amount of cover, when examining species distribution patterns. Further, we investigated the effect of the surrounding landscape heterogeneity on species occupancy. We tested the effect of cover and heterogeneity of trees and shrubs, and the context of the surrounding landscape (number of habitats and distance to an ecotone) on site occupancy of three mammal species (the black wallaby [Wallabia bicolor], the long-nosed bandicoot [Perameles nasuta], and the bush rat [Rattus fuscipes]) within a naturally heterogeneous landscape in a temperate region of Australia. We found that fine-scale heterogeneity of vegetation attributes is an important driver of mammal occurrence of two of these species. Further, we found that, although all three species responded positively to vegetation heterogeneity, different mammals vary in their response to different types of vegetation heterogeneity measurement. For example, the black wallaby responded to the proximity of an ecotone, and the bush rat and the long-nosed bandicoot responded to fine-scale heterogeneity of small tree cover, whereas none of the mammals responded to broad scale heterogeneity (i.e., the number of habitat types). Our results highlight the influence of methodological decisions, such as how heterogeneity vegetation is measured, in quantifying species responses to habitat structures. The findings confirm the importance of choosing meaningful heterogeneity measures when modelling the factors influencing occupancy of the species of interest. PMID:26394327

  15. Random versus Game Trail-Based Camera Trap Placement Strategy for Monitoring Terrestrial Mammal Communities

    PubMed Central

    Cusack, Jeremy J.; Dickman, Amy J.; Rowcliffe, J. Marcus; Carbone, Chris; Macdonald, David W.; Coulson, Tim

    2015-01-01

    Camera trap surveys exclusively targeting features of the landscape that increase the probability of photographing one or several focal species are commonly used to draw inferences on the richness, composition and structure of entire mammal communities. However, these studies ignore expected biases in species detection arising from sampling only a limited set of potential habitat features. In this study, we test the influence of camera trap placement strategy on community-level inferences by carrying out two spatially and temporally concurrent surveys of medium to large terrestrial mammal species within Tanzania’s Ruaha National Park, employing either strictly game trail-based or strictly random camera placements. We compared the richness, composition and structure of the two observed communities, and evaluated what makes a species significantly more likely to be caught at trail placements. Observed communities differed marginally in their richness and composition, although differences were more noticeable during the wet season and for low levels of sampling effort. Lognormal models provided the best fit to rank abundance distributions describing the structure of all observed communities, regardless of survey type or season. Despite this, carnivore species were more likely to be detected at trail placements relative to random ones during the dry season, as were larger bodied species during the wet season. Our findings suggest that, given adequate sampling effort (> 1400 camera trap nights), placement strategy is unlikely to affect inferences made at the community level. However, surveys should consider more carefully their choice of placement strategy when targeting specific taxonomic or trophic groups. PMID:25950183

  16. Inner architecture of vertebral centra in terrestrial and aquatic mammals: a two-dimensional comparative study.

    PubMed

    Dumont, Maitena; Laurin, Michel; Jacques, Florian; Pellé, Eric; Dabin, Willy; de Buffrénil, Vivian

    2013-05-01

    Inner vertebral architecture is poorly known, except in human and laboratory animals. In order to document this topic at a broad comparative level, a 2D-histomorphometric study of vertebral centra was conducted in a sample of 98 therian mammal species, spanning most of the size range and representing the main locomotor adaptations known in therian taxa. Eleven variables relative to the development and geometry of trabecular networks were extracted from CT scan mid-sagittal sections. Phylogeny-informed statistical tests were used to reveal the respective influences of phylogeny, size, and locomotion adaptations on mammalian vertebral structure. The use of random taxon reshuffling and squared change parsimony reveals that 9 of the 11 characteristics (the two exceptions are total sectional area and structural polarization) contain a phylogenetic signal. Linear discriminant analyses suggest that the sampled taxa can be arranged into three categories with respect to locomotion mode: a) terrestrial + flying + digging + amphibious forms, b) coastal oscillatory aquatic taxa, and c) pelagic oscillatory aquatic forms represented by oceanic cetaceans. Pairwise comparison tests and linear regressions show that, when specific size increases, the length of trabecular network (Tt.Tb.Le), as well as trabecular proliferation in total sections (Pr.Tb.Tt), increase with positive allometry. This process occurs in all locomotion categories but is particularly pronounced in pelagic oscillators. Conversely, mean trabecular width has a lesser increase with size in pelagic oscillators. Trabecular orientation is not influenced by size. All tests were corrected for multiple testing. By using six structural variables or indices, locomotion mode can be predicted with a 97.4% success rate for terrestrial forms, 66.7% for coastal oscillatory, and 81.3% for pelagic oscillatory. The possible functional meaning of these results and their potential use for paleobiological inference of locomotion in

  17. Small Mammals: Common Surgical Procedures of Rodents, Ferrets, Hedgehogs, and Sugar Gliders.

    PubMed

    Miwa, Yasutsugu; Sladky, Kurt K

    2016-01-01

    Small mammal surgical procedures are a part of clinical veterinary practice and are performed with regularity. Anesthetic and analgesic techniques are important components of any successful small mammal surgical procedure. Many basic surgical principles used in dogs and cats can be directly applied to small mammals, but tissues tend to be smaller and thinner, and hemostasis is critical with small patients due to risk of death with minimal blood loss. Common surgical procedures in small mammals include integumentary mass and abscess excision, reproductive procedures, gastrointestinal foreign body removal, urolith removal, prolapsed tissues associated with the gastrointestinal tract, intra-abdominal mass excision, and hepatic surgery.

  18. Small mammals as hosts of immature ixodid ticks.

    PubMed

    Horak, I G; Fourie, L J; Braack, L E O

    2005-09-01

    Two hundred and twenty-five small mammals belonging to 16 species were examined for ticks in Free State, Mpumalanga and Limpopo Provinces, South Africa, and 18 ixodid tick species, of which two could only be identified to genus level, were recovered. Scrub hares, Lepus saxatilis, and Cape hares, Lepus capensis, harboured the largest number of tick species. In Free State Province Namaqua rock mice, Aethomys namaquensis, and four-striped grass mice, Rhabdomys pumilio, were good hosts of the immature stages of Haemaphysalis leachi and Rhipicephalus gertrudae, while in Mpumalanga and Limpopo Provinces red veld rats, Aethomys chrysophilus, Namaqua rock mice and Natal multimammate mice, Mastomys natalensis were good hosts of H. leachi and Rhipicephalus simus. Haemaphysalis leachi was the only tick recovered from animals in all three provinces.

  19. Antibodies to selected pathogens in free-ranging terrestrial carnivores and marine mammals in Canada.

    PubMed

    Philippa, J D W; Leighton, F A; Daoust, P Y; Nielsen, O; Pagliarulo, M; Schwantje, H; Shury, T; Van Herwijnen, R; Martina, B E E; Kuiken, T; Van de Bildt, M W G; Osterhaus, A D M E

    2004-07-31

    Antibody titres to selected pathogens (canine adenovirus [CAV-2], feline herpesvirus [FHV], phocine herpesvirus [PHV-1], canine distemper virus, dolphin morbillivirus [DMV], phocine distemper virus [PDV], parainfluenza virus type 3 [PI3], rabies virus, dolphin rhabdovirus [DRV], canine coronavirus, feline coronavirus, feline leukaemia virus, Borrelia burgdorferi and Toxoplasma gondii) were determined in whole blood or serum samples from selected free-ranging terrestrial carnivores and marine mammals, including cougars (Fellis concolor), lynxes (Fellis lynx), American badgers (Taxidea taxus), fishers (Martes pennanti), wolverines (Gulo gulo), wolves (Canis lupus), black bears (Ursus americanus), grizzly bears (Ursus arctos), polar bears (Ursus maritimus), walruses (Odobenus rosmarus) and belugas (Delphinapterus leucas), which had been collected at several locations in Canada between 1984 and 2001. Antibodies to a number of viruses were detected in species in which these infections have not been reported before, for example, antibodies to CAV-2 in walruses, to PDV in black bears, grizzly bears, polar bears, lynxes and wolves, to DMV in grizzly bears, polar bears, walruses and wolves, to PI3 in black bears and fishers, and to DRV in belugas and walruses.

  20. Rickettsial Infections of Fleas Collected From Small Mammals on Four Islands in Indonesia

    DTIC Science & Technology

    2010-01-01

    fever group rickettsiae. R. typhi, the agent of murine typhus , was detected in X. cheopis collected from small mammals in West Java and East...spotted fever group rickettsiae. R. typhi, the agent of murine typhus , was detected in X. cheopis collected from small mammals in West Java and East...Kalimantan. R.felis was detected in X. cheopis collected from small mammals in Manado, North Sulawesi. R. felis and spotted fever group rickettsiae were

  1. Comparison of serum lipid compositions, lipid peroxide, alpha-tocopherol and lipoproteins in captive marine mammals (bottlenose dolphins, spotted seals and West Indian manatees) and terrestrial mammals.

    PubMed

    Kasamatsu, Masahiko; Kawauchi, Rieko; Tsunokawa, Masatoshi; Ueda, Keiichi; Uchida, Eiji; Oikawa, Shin; Higuchi, Hidetoshi; Kawajiri, Takaaki; Uchida, Senzo; Nagahata, Hajime

    2009-04-01

    Concentrations of serum lipid components, lipid peroxide (LPO) and alpha-tocopherol and electrophoretic patterns of lipoproteins in serum samples obtained from captive marine mammals and terrestrial mammals were compared. Serum concentrations of total cholesterol, free fatty acid, and phospholipid in fish-eating animals were significantly higher than those in manatees and cows. Serum LPO and alpha-tocopherol concentrations in the fish-eating animals were also significantly higher than those in manatees, cows and dogs. Different patterns of densitometric scans of low density lipoprotein (LDL) and a significantly lower percentage of LDL were demonstrated in the dolphins compared with the seals, cow and dogs. The concentration of LPO was significantly correlated with triglyceride and phospholipid concentrations in serum from the dolphins. These results suggest that triglyceride and phospholipid are susceptible to oxidative reaction in fish-eating animals. Evaluation of serum lipids, LPO and alpha-tocopherol concentrations is needed for nutritional husbandry for fish-eating animals.

  2. Phylogenetic Analysis of Conservation Priorities for Aquatic Mammals and Their Terrestrial Relatives, with a Comparison of Methods

    PubMed Central

    May-Collado, Laura J.; Agnarsson, Ingi

    2011-01-01

    Background Habitat loss and overexploitation are among the primary factors threatening populations of many mammal species. Recently, aquatic mammals have been highlighted as particularly vulnerable. Here we test (1) if aquatic mammals emerge as more phylogenetically urgent conservation priorities than their terrestrial relatives, and (2) if high priority species are receiving sufficient conservation effort. We also compare results among some phylogenetic conservation methods. Methodology/Principal Findings A phylogenetic analysis of conservation priorities for all 620 species of Cetartiodactyla and Carnivora, including most aquatic mammals. Conservation priority ranking of aquatic versus terrestrial species is approximately proportional to their diversity. However, nearly all obligated freshwater cetartiodactylans are among the top conservation priority species. Further, ∼74% and 40% of fully aquatic cetartiodactylans and carnivores, respectively, are either threatened or data deficient, more so than their terrestrial relatives. Strikingly, only 3% of all ‘high priority’ species are thought to be stable. An overwhelming 97% of these species thus either show decreasing population trends (87%) or are insufficiently known (10%). Furthermore, a disproportional number of highly evolutionarily distinct species are experiencing population decline, thus, such species should be closely monitored even if not currently threatened. Comparison among methods reveals that exact species ranking differs considerably among methods, nevertheless, most top priority species consistently rank high under any method. While we here favor one approach, we also suggest that a consensus approach may be useful when methods disagree. Conclusions/Significance These results reinforce prior findings, suggesting there is an urgent need to gather basic conservation data for aquatic mammals, and special conservation focus is needed on those confined to freshwater. That evolutionarily distinct

  3. The impact of Great Cormorants on biogenic pollution of land ecosystems: Stable isotope signatures in small mammals.

    PubMed

    Balčiauskas, Linas; Skipitytė, Raminta; Jasiulionis, Marius; Trakimas, Giedrius; Balčiauskienė, Laima; Remeikis, Vidmantas

    2016-09-15

    Studying the isotopic composition of the hair of two rodent species trapped in the territories of Great Cormorant colonies, we aimed to show that Great Cormorants transfer biogens from aquatic ecosystems to terrestrial ecosystems, and that these substances reach small mammals through the trophic cascade, thus influencing the nutrient balance in the terrestrial ecosystem. Analysis of δ(13)C and δ(15)N was performed on two dominant species of small mammals, Apodemus flavicollis and Myodes glareolus, inhabiting the territories of the colonies. For both species, the values of δ(13)C and δ(15)N were higher in the animals trapped in the territories of the colonies than those in control territories. In the hair of A. flavicollis and M. glareolus, the highest values of δ(15)N (16.31±3.01‰ and 17.86±2.76‰, respectively) were determined in those animals trapped in the biggest Great Cormorant colony. δ(15)N values were age dependent, highest in adult A. flavicollis and M. glareolus and lowest in juvenile animals. For δ(13)C values, age-dependent differences were not registered. δ(15)N values in both small mammal species from the biggest Great Cormorant colony show direct dependence on the intensity of influence. Biogenic pollution is at its strongest in the territories of the colonies with nests, significantly diminishing in the ecotones of the colonies and further in the control zones, where the influence of birds is negligible. Thus, Great Cormorant colonies alter ecosystem functioning by enrichment with biogens, with stable isotope values in small mammals significantly higher in the affected territories.

  4. Avian ecosystem functions are influenced by small mammal ecosystem engineering

    PubMed Central

    2013-01-01

    Background Birds are important mobile link species that contribute to landscape-scale patterns by means of pollination, seed dispersal, and predation. Birds are often associated with habitats modified by small mammal ecosystem engineers. We investigated whether birds prefer to forage on degu (Octodon degus) runways by comparing their foraging effort across sites with a range of runway densities, including sites without runways. We measured granivory by granivorous and omnivorous birds at Rinconada de Maipú, central Chile. As a measure of potential bird foraging on insects, we sampled invertebrate prey richness and abundance across the same sites. We then quantified an index of plot-scale functional diversity due to avian foraging at the patch scale. Results We recorded that birds found food sources sooner and ate more at sites with higher densities of degu runways, cururo mounds, trees, and fewer shrubs. These sites also had higher invertebrate prey richness but lower invertebrate prey abundance. This implies that omnivorous birds, and possibly insectivorous birds, forage for invertebrates in the same plots with high degu runway densities where granivory takes place. In an exploratory analysis we also found that plot-scale functional diversity for four avian ecosystem functions were moderately to weakly correllated to expected ecosystem function outcomes at the plot scale. Conclusions Degu ecosystem engineering affects the behavior of avian mobile link species and is thus correlated with ecosystem functioning at relatively small spatial scales. PMID:24359802

  5. Secondary poisoning risk assessment of terrestrial birds and mammals exposed to nickel.

    PubMed

    DeForest, David K; Schlekat, Christian E; Brix, Kevin V; Fairbrother, Anne

    2012-01-01

    The European Union's Existing Substances regulation (EEC 793/93) was developed to assess the ecological risks posed by chemical substances such as Ni and includes the assessment of secondary poisoning risks. The basic structure of this secondary poisoning risk assessment followed the Technical Guidance Document on Risk Assessment and thus included development of predicted exposure concentrations (PECs) and predicted no-effect concentrations (PNECs). A PEC to PNEC ratio greater than 1.0 is indicative of potential risk. The Technical Guidance Document on Risk Assessment provides a generic framework for assessing secondary poisoning risks and prescribes the following terrestrial food chain: soil → earthworm → worm-eating bird or mammal. This secondary poisoning evaluation was conducted at the regional level, and it was found that the generic approach resulted in widespread estimates of potential risk, even at ambient Ni soil concentrations. Accordingly, a tiered approach was used with increasing levels of refinement, including consideration of bioavailability, consideration of a variable diet, and development of dose-based PNEC values. Based on the refined approach, all PEC to PNEC ratios were less than 1.0, except for a ratio of 1.4 in a scenario focused on a regional clay soil, which was of natural origin. This regional-level secondary poisoning evaluation highlighted key risk assessment components that should be considered in future localized secondary poisoning assessments of Ni and other metals, including ingestion rate to body weight ratios for the test organisms used to derive PNECs versus the representative wildlife species evaluated, the appropriateness of high assessment factors for deriving PNECs for naturally occurring essential elements, representative dietary compositions, relative metal bioavailability between the dietary toxicity study and natural diets, and ground-truthing of the risk predictions versus background concentrations.

  6. Radiocarbon dating of small terrestrial gastropod shells in North America

    USGS Publications Warehouse

    Pigati, J.S.; Rech, J.A.; Nekola, J.C.

    2010-01-01

    Fossil shells of small terrestrial gastropods are commonly preserved in wetland, alluvial, loess, and glacial deposits, as well as in sediments at many archeological sites. These shells are composed largely of aragonite (CaCO3) and potentially could be used for radiocarbon dating, but they must meet two criteria before their 14C ages can be considered to be reliable: (1) when gastropods are alive, the 14C activity of their shells must be in equilibrium with the 14C activity of the atmosphere, and (2) after burial, their shells must behave as closed systems with respect to carbon. To evaluate the first criterion, we conducted a comprehensive examination of the 14C content of the most common small terrestrial gastropods in North America, including 247 AMS measurements of modern shell material (3749 individual shells) from 46 different species. The modern gastropods that we analyzed were all collected from habitats on carbonate terrain and, therefore, the data presented here represent worst-case scenarios. In sum, ~78% of the shell aliquots that we analyzed did not contain dead carbon from limestone or other carbonate rocks even though it was readily available at all sites, 12% of the aliquots contained between 5 and 10% dead carbon, and a few (3% of the total) contained more than 10%. These results are significantly lower than the 20-30% dead carbon that has been reported previously for larger taxa living in carbonate terrain. For the second criterion, we report a case study from the American Midwest in which we analyzed fossil shells of small terrestrial gastropods (7 taxa; 18 AMS measurements; 173 individual shells) recovered from late-Pleistocene sediments. The fossil shells yielded 14C ages that were statistically indistinguishable from 14C ages of well-preserved plant macrofossils from the same stratum. Although just one site, these results suggest that small terrestrial gastropod shells may behave as closed systems with respect to carbon over geologic

  7. Enamel prism morphology in molar teeth of small eutherian mammals.

    PubMed

    Dumont, E R

    1996-01-01

    Data summarizing enamel prism shape, size and spacing are reported for the molar enamel of 55 species of small eutherian mammals including primates, bats, tree shrews, flying lemurs, insectivorans and representatives of a variety of fossil families. Confocal photomicrographs reveal that the subsurface enamel of most species is characterized by arc-shaped prisms. The lack of a clear distinction between pattern 2 and pattern 3 prism configurations within single specimens suggests that the broad category "arc-shaped prisms" is the most appropriate descriptive grouping for these species. Of the total sample, three species exhibit only circular prisms while no evidence of prismatic enamel was found in two bats. Prism shape is not an informative phylogenetic character at the ordinal level for these morphologically primitive and relatively thin-enameled taxa. Significant differences between species in several prism size and spacing variables (central distance between prisms, prism diameter, prism area and the ratio of prism area to estimated ameloblast area) suggest the potential for further analyses of quantitative variation to document evolutionary relationships within or among family-level groups.

  8. Hantavirus testing in small mammal populations of northcentral New Mexico

    SciTech Connect

    Biggs, J.; Bennett, K.; Foxx, T.

    1995-07-01

    In 1993, an outbreak of a new strain of hantavirus in the southwestern US indicated that deer mice (Peromyscus maniculatus) was the primary carrier of the virus. In 1993 and 1994, the Ecological Studies Team (EST) at Los Alamos National Laboratory surveyed small mammal populations in Los Alamos County, New Mexico, primarily for ecological risk assessment (ecorisk) studies. At the request of the Centers for Disease Control (CDC) and the School of Medicine at the University of New Mexico, EST also collected blood samples from captured animals for use in determining seroprevalence of hantavirus in this region due to the recent outbreak of this virus in the four-comers region of the Southwest. The deer mouse was the most commonly captured species during the tripping sessions. Other species sampled included harvest mice (Reithrodontomys megalotis), least chipmunk (Eutamias minimus), long-tailed vole (Microtus longicaudus), Mexican woodrat (Neotoma mexicana), and brush mouse (Peromyscus boylii). The team collected blood samples from tripped animals following CDC`s suggested guidelines. Results of the 1993 and 1994 hantavirus testing identified a total overall seroprevalence of approximately 5.5% and 4.2%, respectively. The highest seroprevalence rates were found in deer mice seri (3--6%), but results on several species were inconclusive; further studies will be necessary, to quantify seroprevalence rates in those species. Seroprevalence rates for Los Alamos County were much lower than elsewhere in the region.

  9. Purine nucleoside phosphorylase and xanthine oxidase activities in erythrocytes and plasma from marine, semiaquatic and terrestrial mammals.

    PubMed

    López-Cruz, Roberto I; Pérez-Milicua, Myrna Barjau; Crocker, Daniel E; Gaxiola-Robles, Ramón; Bernal-Vertiz, Jaime A; de la Rosa, Alejandro; Vázquez-Medina, José P; Zenteno-Savín, Tania

    2014-05-01

    Purine nucleoside phosphorylase (PNP) and xanthine oxidase (XO) are key enzymes involved in the purine salvage pathway. PNP metabolizes purine bases to synthetize purine nucleotides whereas XO catalyzes the oxidation of purines to uric acid. In humans, PNP activity is reported to be high in erythrocytes and XO activity to be low in plasma; however, XO activity increases after ischemic events. XO activity in plasma of northern elephant seals has been reported during prolonged fasting and rest and voluntary associated apneas. The objective of this study was to analyze circulating PNP and XO activities in marine mammals adapted to tolerate repeated cycles of ischemia/reperfusion associated with diving (bottlenose dolphin, northern elephant seal) in comparison with semiaquatic (river otter) and terrestrial mammals (human, pig). PNP activities in plasma and erythrocytes, as well as XO activity in plasma, from all species were quantified by spectrophotometry. No clear relationship in circulating PNP or XO activity could be established between marine, semiaquatic and terrestrial mammals. Erythrocytes from bottlenose dolphins and humans are highly permeable to nucleosides and glucose, intraerythrocyte PNP activity may be related to a release of purine nucleotides from the liver. High-energy costs will probably mean a higher ATP degradation rate in river otters, as compared to northern elephant seals or dolphins. Lower erythrocyte PNP activity and elevated plasma XO activity in northern elephant seal could be associated with fasting and/or sleep- and dive-associated apneas.

  10. Line Transect Surveys Underdetect Terrestrial Mammals: Implications for the Sustainability of Subsistence Hunting.

    PubMed

    Fragoso, José M V; Levi, Taal; Oliveira, Luiz F B; Luzar, Jeffrey B; Overman, Han; Read, Jane M; Silvius, Kirsten M

    2016-01-01

    Conservation of Neotropical game species must take into account the livelihood and food security needs of local human populations. Hunting management decisions should therefore rely on abundance and distribution data that are as representative as possible of true population sizes and dynamics. We simultaneously applied a commonly used encounter-based method and an infrequently used sign-based method to estimate hunted vertebrate abundance in a 48,000-km2 indigenous landscape in southern Guyana. Diurnal direct encounter data collected during three years along 216, four-kilometer -long transects consistently under-detected many diurnal and nocturnal mammal species readily detected through sign. Of 32 species analyzed, 31 were detected by both methods; however, encounters did not detect one and under-detected another 12 of the most heavily hunted species relative to sign, while sign under-detected 12 never or rarely collected species relative to encounters. The six most important game animals in the region, all ungulates, were not encountered at 11-40% of village and control sites or on 29-72% of transects where they were detected by sign. Using the sign methodology, we find that tapirs, one of the terrestrial vertebrates considered most sensitive to overexploitation, are present at many sites where they were never visually detected during distance sampling. We find that this is true for many other species as well. These high rates of under-detection suggest that behavioral changes in hunted populations may affect apparent occurrence and abundance of these populations. Accumulation curves (detection of species on transects) were much steeper for sign for 12 of 16 hunted species than for encounters, but that pattern was reversed for 12 of 16 species unhunted in our area. We conclude that collection of sign data is an efficient and effective method of monitoring hunted vertebrate populations that complements encounter and camera-trapping methods in areas impacted by

  11. Line Transect Surveys Underdetect Terrestrial Mammals: Implications for the Sustainability of Subsistence Hunting

    PubMed Central

    Levi, Taal; Oliveira, Luiz F. B.; Luzar, Jeffrey B.; Overman, Han; Read, Jane M.

    2016-01-01

    Conservation of Neotropical game species must take into account the livelihood and food security needs of local human populations. Hunting management decisions should therefore rely on abundance and distribution data that are as representative as possible of true population sizes and dynamics. We simultaneously applied a commonly used encounter-based method and an infrequently used sign-based method to estimate hunted vertebrate abundance in a 48,000-km2 indigenous landscape in southern Guyana. Diurnal direct encounter data collected during three years along 216, four-kilometer -long transects consistently under-detected many diurnal and nocturnal mammal species readily detected through sign. Of 32 species analyzed, 31 were detected by both methods; however, encounters did not detect one and under-detected another 12 of the most heavily hunted species relative to sign, while sign under-detected 12 never or rarely collected species relative to encounters. The six most important game animals in the region, all ungulates, were not encountered at 11–40% of village and control sites or on 29–72% of transects where they were detected by sign. Using the sign methodology, we find that tapirs, one of the terrestrial vertebrates considered most sensitive to overexploitation, are present at many sites where they were never visually detected during distance sampling. We find that this is true for many other species as well. These high rates of under-detection suggest that behavioral changes in hunted populations may affect apparent occurrence and abundance of these populations. Accumulation curves (detection of species on transects) were much steeper for sign for 12 of 16 hunted species than for encounters, but that pattern was reversed for 12 of 16 species unhunted in our area. We conclude that collection of sign data is an efficient and effective method of monitoring hunted vertebrate populations that complements encounter and camera-trapping methods in areas impacted by

  12. The physiological costs of reproduction in small mammals.

    PubMed

    Speakman, John R

    2008-01-27

    Life-history trade-offs between components of fitness arise because reproduction entails both gains and costs. Costs of reproduction can be divided into ecological and physiological costs. The latter have been rarely studied yet are probably a dominant component of the effect. A deeper understanding of life-history evolution will only come about once these physiological costs are better understood. Physiological costs may be direct or indirect. Direct costs include the energy and nutrient demands of the reproductive event, and the morphological changes that are necessary to facilitate achieving these demands. Indirect costs may be optional 'compensatory costs' whereby the animal chooses to reduce investment in some other aspect of its physiology to maximize the input of resource to reproduction. Such costs may be distinguished from consequential costs that are an inescapable consequence of the reproductive event. In small mammals, the direct costs of reproduction involve increased energy, protein and calcium demands during pregnancy, but most particularly during lactation. Organ remodelling is necessary to achieve the high demands of lactation and involves growth of the alimentary tract and associated organs such as the liver and pancreas. Compensatory indirect costs include reductions in thermogenesis, immune function and physical activity. Obligatory consequential costs include hyperthermia, bone loss, disruption of sleep patterns and oxidative stress. This is unlikely to be a complete list. Our knowledge of these physiological costs is currently at best described as rudimentary. For some, we do not even know whether they are compensatory or obligatory. For almost all of them, we have no idea of exact mechanisms or how these costs translate into fitness trade-offs.

  13. A long-lasting wireless stimulator for small mammals

    PubMed Central

    Hentall, Ian D.

    2013-01-01

    The chronic effects of electrical stimulation in unrestrained awake rodents are best studied with a wireless neural stimulator that can operate unsupervised for several weeks or more. A robust, inexpensive, easily built, cranially implantable stimulator was developed to explore the restorative effects of brainstem stimulation after neurotrauma. Its connectorless electrodes directly protrude from a cuboid epoxy capsule containing all circuitry and power sources. This physical arrangement prevents fluid leaks or wire breakage and also simplifies and speeds implantation. Constant-current pulses of high compliance (34 volts) are delivered from a step-up voltage regulator under microprocessor control. A slowly pulsed magnetic field controls activation state and stimulation parameters. Program status is signaled to a remote reader by interval-modulated infrared pulses. Capsule size is limited by the two batteries. Silver oxide batteries rated at 8 mA-h were used routinely in 8 mm wide, 15 mm long and 4 mm high capsules. Devices of smaller contact area (5 by 12 mm) but taller (6 mm) were created for mice. Microstimulation of the rat's raphe nuclei with intermittent 5-min (50% duty cycle) trains of 30 μA, 1 ms pulses at 8 or 24 Hz frequency during 12 daylight hours lasted 21.1 days ±0.8 (mean ± standard error, Kaplan-Meir censored estimate, n = 128). Extended lifetimes (>6 weeks, no failures, n = 16) were achieved with larger batteries (44 mA-h) in longer (18 mm), taller (6 mm) capsules. The circuit and electrode design are versatile; simple modifications allowed durable constant-voltage stimulation of the rat's sciatic nerve through a cylindrical cathode from a subcutaneous pelvic capsule. Devices with these general features can address in small mammals many of the biological and technical questions arising neurosurgically with prolonged peripheral or deep brain stimulation. PMID:24130527

  14. Terrestrial Scavenging of Marine Mammals: Cross-Ecosystem Contaminant Transfer and Potential Risks to Endangered California Condors (Gymnogyps californianus).

    PubMed

    Kurle, Carolyn M; Bakker, Victoria J; Copeland, Holly; Burnett, Joe; Jones Scherbinski, Jennie; Brandt, Joseph; Finkelstein, Myra E

    2016-09-06

    The critically endangered California condor (Gymnogyps californianus) has relied intermittently on dead-stranded marine mammals since the Pleistocene, and this food source is considered important for their current recovery. However, contemporary marine mammals contain persistent organic pollutants that could threaten condor health. We used stable carbon and nitrogen isotope, contaminant, and behavioral data in coastal versus noncoastal condors to quantify contaminant transfer from marine mammals and created simulation models to predict the risk of reproductive impairment for condors from exposure to DDE (p,p'-DDE), a major metabolite of the chlorinated pesticide DDT. Coastal condors had higher whole blood isotope values and mean concentrations of contaminants associated with marine mammals, including mercury (whole blood), sum chlorinated pesticides (comprised of ∼95% DDE) (plasma), sum polychlorinated biphenyls (PCBs) (plasma), and sum polybrominated diphenyl ethers (PBDEs) (plasma), 12-100-fold greater than those of noncoastal condors. The mean plasma DDE concentration for coastal condors was 500 ± 670 (standard deviation) (n = 22) versus 24 ± 24 (standard deviation) (n = 8) ng/g of wet weight for noncoastal condors, and simulations predicted ∼40% of breeding-age coastal condors have DDE levels associated with eggshell thinning in other avian species. Our analyses demonstrate potentially harmful levels of marine contaminant transfer to California condors, which could hinder the recovery of this terrestrial species.

  15. Negative effects of an exotic grass invasion on small-mammal communities.

    PubMed

    Freeman, Eric D; Sharp, Tiffanny R; Larsen, Randy T; Knight, Robert N; Slater, Steven J; McMillan, Brock R

    2014-01-01

    Exotic invasive species can directly and indirectly influence natural ecological communities. Cheatgrass (Bromus tectorum) is non-native to the western United States and has invaded large areas of the Great Basin. Changes to the structure and composition of plant communities invaded by cheatgrass likely have effects at higher trophic levels. As a keystone guild in North American deserts, granivorous small mammals drive and maintain plant diversity. Our objective was to assess potential effects of invasion by cheatgrass on small-mammal communities. We sampled small-mammal and plant communities at 70 sites (Great Basin, Utah). We assessed abundance and diversity of the small-mammal community, diversity of the plant community, and the percentage of cheatgrass cover and shrub species. Abundance and diversity of the small-mammal community decreased with increasing abundance of cheatgrass. Similarly, cover of cheatgrass remained a significant predictor of small-mammal abundance even after accounting for the loss of the shrub layer and plant diversity, suggesting that there are direct and indirect effects of cheatgrass. The change in the small-mammal communities associated with invasion of cheatgrass likely has effects through higher and lower trophic levels and has the potential to cause major changes in ecosystem structure and function.

  16. Negative Effects of an Exotic Grass Invasion on Small-Mammal Communities

    PubMed Central

    Freeman, Eric D.; Sharp, Tiffanny R.; Larsen, Randy T.; Knight, Robert N.; Slater, Steven J.; McMillan, Brock R.

    2014-01-01

    Exotic invasive species can directly and indirectly influence natural ecological communities. Cheatgrass (Bromus tectorum) is non-native to the western United States and has invaded large areas of the Great Basin. Changes to the structure and composition of plant communities invaded by cheatgrass likely have effects at higher trophic levels. As a keystone guild in North American deserts, granivorous small mammals drive and maintain plant diversity. Our objective was to assess potential effects of invasion by cheatgrass on small-mammal communities. We sampled small-mammal and plant communities at 70 sites (Great Basin, Utah). We assessed abundance and diversity of the small-mammal community, diversity of the plant community, and the percentage of cheatgrass cover and shrub species. Abundance and diversity of the small-mammal community decreased with increasing abundance of cheatgrass. Similarly, cover of cheatgrass remained a significant predictor of small-mammal abundance even after accounting for the loss of the shrub layer and plant diversity, suggesting that there are direct and indirect effects of cheatgrass. The change in the small-mammal communities associated with invasion of cheatgrass likely has effects through higher and lower trophic levels and has the potential to cause major changes in ecosystem structure and function. PMID:25269073

  17. How may the regional climate change redraw the European terrestrial wild mammals' living territory in the 21st century?

    NASA Astrophysics Data System (ADS)

    Nagy, Julia; Bartholy, Judit; Pongracz, Rita; Hufnagel, Levente

    2013-04-01

    Climate is one of the abiotic factors, which controls primarily the range areas of wildlife. Animals tend to occupy geographical regions with climatic conditions, which are optimal to their specific needs. Due to the projected global warming and climate change the living territory of wild animals' may be reshaped in the future, some of the species may even suffer extinction. In this research we aim to estimate how climate change alters the distributions of European terrestrial mammal species and modifies biodiversity in the 21st century. For this purpose, first, hierarchical cluster analysis is applied to species for forming major groups. Climatic information is provided by using the E-OBS gridded database for 1961-1990. Then, carefully selecting typical species from the major groups it is possible to predict changes in area by displaying their climate indicator profile maps. For the range datasets the Atlas of European Mammals are analyzed, which was published in 1999 and is now widely used as a reference work. It contains data for pre-1970 and post-1970 presence of mammal species in Europe. Then, in order to assess future changes, available datasets of regional climate model results from the European project ENSEMBLES for 1951-2100 using the moderate SRES A1B emission scenario are considered with 25 km horizontal resolution. Simultaneous analysis of climate simulations and animal range datasets enables us to evaluate the vulnerability of European terrestrial mammal species to regional climate change. The results suggest that rapid change and significant decline in habitats and fauna redraw the wild animals' living territory and make them migrate northward.

  18. Integrating small mammal community variables into aircraft-wildlife collision management plans at Namibian airports.

    PubMed

    Hauptfleisch, Morgan L; Avenant, Nico L

    2015-11-01

    Understanding ecosystems within and around airports can help to determine the causes and possible mitigation measures for collisions between aircraft and wildlife. Small mammal communities are an important component of the semi-arid savanna ecosystems of Namibia, its productivity and its ecosystem integrity. They are also a major direct attractant for raptors at airports. The present study compared the abundance and diversity of small mammals between Namibia's 2 main airport properties (Hosea Kutako International Airport and Eros Airport), and among areas of land used for various purposes surrounding the airports. A total of 2150 small mammals (3 orders, 11 species) were captured over 4 trapping seasons. Small mammal abundance was significantly higher at the end of the growing season than during the non-growing season. The grass mowing regimen in current management plans at the airports resulted in a significant reduction of small mammal abundance at Hosea Kutako during the non-growing season only, thus indicating that annual mowing is effective but insufficient to reduce the overall abundance of mammal prey species for raptors. Small mammal numbers were significantly higher at Hosea Kutako Airport compared to the cattle and game farming land surrounding the airport, while no differences in small mammal densities or diversity were found for areas with different land uses at and surrounding Eros. The study suggests that the fence around Hosea Kutako provides a refuge for small mammals, resulting in higher densities. It also indicates that different surrounding land use practices result in altered ecosystem function and productivity, an important consideration when identifying wildlife attractants at airports.

  19. Small mammal diversity loss in response to late-Pleistocene climatic change.

    PubMed

    Blois, Jessica L; McGuire, Jenny L; Hadly, Elizabeth A

    2010-06-10

    Communities have been shaped in numerous ways by past climatic change; this process continues today. At the end of the Pleistocene epoch about 11,700 years ago, North American communities were substantially altered by the interplay of two events. The climate shifted from the cold, arid Last Glacial Maximum to the warm, mesic Holocene interglacial, causing many mammal species to shift their geographic distributions substantially. Populations were further stressed as humans arrived on the continent. The resulting megafaunal extinction event, in which 70 of the roughly 220 largest mammals in North America (32%) became extinct, has received much attention. However, responses of small mammals to events at the end of the Pleistocene have been much less studied, despite the sensitivity of these animals to current and future environmental change. Here we examine community changes in small mammals in northern California during the last 'natural' global warming event at the Pleistocene-Holocene transition and show that even though no small mammals in the local community became extinct, species losses and gains, combined with changes in abundance, caused declines in both the evenness and richness of communities. Modern mammalian communities are thus depauperate not only as a result of megafaunal extinctions at the end of the Pleistocene but also because of diversity loss among small mammals. Our results suggest that across future landscapes there will be some unanticipated effects of global change on diversity: restructuring of small mammal communities, significant loss of richness, and perhaps the rising dominance of native 'weedy' species.

  20. A small-scale survey of hantavirus in mammals from eastern Poland.

    PubMed

    Wójcik-Fatla, Angelina; Zając, Violetta; Knap, Józef P; Sroka, Jacek; Cisak, Ewa; Sawczyn, Anna; Dutkiewicz, Jacek

    2013-01-01

    Samples of 30 dead small mammals each were collected on area 'A' located in eastern Poland which is exposed to flooding by the Vistula river, and on the area 'B', also located in eastern Poland but not exposed to flooding. Kidneys and livers of the mammals were examined by the PCR and nested PCR methods for the presence of hantavirus RNA. Out of 7 species of small mammals examined, the presence of hantaviruses was detected in 4 of them. Hantavirus prevalence was low in Apodemus agrarius (2.6%), the most numerous mammal species, whereas in the remaining 3 positive species (Microtus agrestis, Myodes glareolus, Sorex araneus) this was 12.5-100%. The presence of hantaviruses was detected only in the animals found on area 'A' exposed to flooding, and their prevalence was statistically greater compared to area 'B' not exposed to flooding (16.7% vs. 0%, p=0.0345). The overall positivity of the examined small mammals population from the areas 'A' and 'B' was 8.3%. The sequence analysis of the samples positive for hantavirus proved that the amplified products showed 77-86% homology with the L segment sequence of hantavirus Fusong-Mf-731 isolated from Microtus fortis in China. The presented study is the first to demonstrate the occurrence of hantavirus infection in small mammals from eastern Poland, and the first to demonstrate the significant relationship between flooding and the prevalence of hantaviruses in small mammals.

  1. Effects of corridors on home range sizes and interpatch movements of three small mammal species.

    SciTech Connect

    Mabry, Karen, E.; Barrett, Gary, W.

    2002-04-30

    Mabry, K.E., and G.W. Barrett. 2002. Effects of corridors on home range sizes and interpatch movements of three small mammal species. Landscape Ecol. 17:629-636. Corridors are predicted to benefit populations in patchy habitats by promoting movement, which should increase population densities, gene flow, and recolonization of extinct patch populations. However, few investigators have considered use of the total landscape, particularly the possibility of interpatch movement through matrix habitat, by small mammals. This study compares home range sizes of 3 species of small mammals, the cotton mouse, old field mouse and cotton rat between patches with and without corridors. Corridor presence did not have a statistically significant influence on average home range size. Habitat specialization and sex influenced the probability of an individual moving between 2 patches without corridors. The results of this study suggest that small mammals may be more capable of interpatch movement without corridors than is frequently assumed.

  2. Diversity and habitat association of small mammals in Aridtsy forest, Awi Zone, Ethiopia

    PubMed Central

    BANTIHUN, Getachew; BEKELE, Afework

    2015-01-01

    Here, we conducted a survey to examine the diversity, distribution and habitat association of small mammals from August 2011 to February 2012 incorporating both wet and dry seasons in Aridtsy forest, Awi Zone, Ethiopia. Using Sherman live traps and snap traps in four randomly selected trapping grids, namely, natural forest, bushland, grassland and farmland, a total of 468 individuals comprising eight species of small mammals (live traps) and 89 rodents of six species (snap traps) were trapped in 2352 and 1200 trap nights, respectively. The trapped small mammals included seven rodents and one insectivore: Lophuromys flavopuntatus (30.6%), Arvicanthis dembeensis (25.8%), Stenocephalemys albipes (20%), Mastomys natalensis (11.6%), Pelomys harringtoni (6.4%), Acomys cahirinus (4.3%), Lemniscomys zebra (0.2%) and the greater red musk shrew (Crocidura flavescens, 1.1%). Analysis showed statistically significant variations in the abundance and habitat preferences of small mammals between habitats during wet and dry seasons. PMID:25855227

  3. NITROGEN OUTPUTS OF SMALL MAMMALS FROM FECAL AND URINE DEPOSITION: IMPLICATIONS FOR NITROGEN CYCLING

    EPA Science Inventory

    The contribution of small mammals in nitrogen cycling is poorly understood and could have reverberations back to the producer community by maintaining or even magnifying increased nitrogen availability. Our objective was to model nitrogen outputs (deposition of feces and urine) ...

  4. Diversity and habitat association of small mammals in Aridtsy forest, Awi Zone, Ethiopia.

    PubMed

    Bantihun, Getachew; Bekele, Afework

    2015-03-18

    Here, we conducted a survey to examine the diversity, distribution and habitat association of small mammals from August 2011 to February 2012 incorporating both wet and dry seasons in Aridtsy forest, Awi Zone, Ethiopia. Using Sherman live traps and snap traps in four randomly selected trapping grids, namely, natural forest, bushland, grassland and farmland, a total of 468 individuals comprising eight species of small mammals (live traps) and 89 rodents of six species (snap traps) were trapped in 2352 and 1200 trap nights, respectively. The trapped small mammals included seven rodents and one insectivore: Lophuromys flavopuntatus (30.6%), Arvicanthis dembeensis (25.8%), Stenocephalemys albipes (20%), Mastomys natalensis (11.6%), Pelomys harringtoni (6.4%), Acomys cahirinus (4.3%), Lemniscomys zebra (0.2%) and the greater red musk shrew (Crocidura flavescens, 1.1%). Analysis showed statistically significant variations in the abundance and habitat preferences of small mammals between habitats during wet and dry seasons.

  5. 2002 Small Mammal Inventory at Lawrence Livermore National Laboratory, Site 300

    SciTech Connect

    West, E; Woollett, J

    2004-11-16

    To assist the University of California in obtaining biological assessment information for the ''2004 Environmental Impact Statement for Continued Operation of Lawrence Livermore National Laboratory (LLNL)'', Jones & Stokes conducted an inventory of small mammals in six major vegetation communities at Site 300. These communities were annual grassland, native grassland, oak savanna, riparian corridor, coastal scrub, and seep/spring wetlands. The principal objective of this study was to assess the diversity and abundance of small mammal species in these communities, as well as the current status of any special-status small mammal species found in these communities. Surveys in the native grassland community were conducted before and after a controlled fire management burn of the grasslands to qualitatively evaluate any potential effects of fire on small mammals in the area.

  6. How-to-Do-It: Tracing Small Mammal Movements with Fluorescent Pigments.

    ERIC Educational Resources Information Center

    Mullican, Tim R.; Streubel, Donald P.

    1989-01-01

    Discussed is an activity designed to teach small mammal ecology and the scientific method using fluorescent dyes and pigments. Procedures for analyzing home ranges and social organizations are described. A list of 16 references is included. (CW)

  7. Land use and small mammal predation effects on shortgrass prairie birds

    USGS Publications Warehouse

    Stanley, T.R.

    2010-01-01

    Grassland birds endemic to the central shortgrass prairie ecoregion of the United States have experienced steep and widespread declines over the last 3 decades, and factors influencing reproductive success have been implicated. Nest predation is the major cause of nest failure in passerines, and nesting success for some shortgrass prairie birds is exceptionally low. The 3 primary land uses in the central shortgrass prairie ecoregion are native shortgrass prairie rangeland (62), irrigated and nonirrigated cropland (29), and Conservation Reserve Program (CRP, 8). Because shortgrasscropland edges and CRP may alter the community of small mammal predators of grassland bird nests, I sampled multiple sites on and near the Pawnee National Grasslands in northeast Colorado, USA, to evaluate 1) whether small mammal species richness and densities were greater in CRP fields and shortgrass prairiecropland edges compared to shortgrass prairie habitats, and 2) whether daily survival probabilities of ground-nesting grassland bird nests were negatively correlated with densities of small mammals. Small mammal species richness and densities, estimated using trapping webs, were generally greater along edges and on CRP sites compared to shortgrass sites. Vegetation did not differ among edges and shortgrass sites but did differ among CRP and shortgrass sites. Daily survival probabilities of artificial nests at edge and CRP sites and natural nests at edge sites did not differ from shortgrass sites, and for natural nests small mammal densities did not affect nest survival. However, estimated daily survival probability of artificial nests was inversely proportional to thirteen-lined ground squirrel (Spermophilus tridecemlineatus) densities. In conclusion, these data suggest that although land-use patterns on the shortgrass prairie area in my study have substantial effects on the small mammal community, insufficient data existed to determine whether land-use patterns or small mammal density

  8. Scaling of metabolic rate on body mass in small laboratory mammals

    NASA Technical Reports Server (NTRS)

    Pace, N.; Rahlmann, D. F.; Smith, A. H.

    1980-01-01

    The scaling of metabolic heat production rate on body mass is investigated for five species of small laboratory mammal in order to define selection of animals of metabolic rates and size range appropriate for the measurement of changes in the scaling relationship upon exposure to weightlessness in Shuttle/Spacelab experiment. Metabolic rates were measured according to oxygen consumption and carbon dioxide production for individual male and female Swiss-Webster mice, Syrian hamsters, Simonsen albino rats, Hartley guinea pigs and New Zealand white rabbits, which range in mass from 0.05 to 5 kg mature body size, at ages of 1, 2, 3, 5, 8, 12, 18 and 24 months. The metabolic intensity, defined as the heat produced per hour per kg body mass, is found to decrease dramatically with age until the animals are 6 to 8 months old, with little or no sex difference. When plotted on a logarithmic graph, the relation of metabolic rate to total body mass is found to obey a power law of index 0.676, which differs significantly from the classical value of 0.75. When the values for the mice are removed, however, an index of 0.749 is obtained. It is thus proposed that six male animals, 8 months of age, of each of the four remaining species be used to study the effects of gravitational loading on the metabolic energy requirements of terrestrial animals.

  9. The interaction of disturbances and small mammal community dynamics in a lowland forest in Belize.

    PubMed

    Klinger, R

    2006-11-01

    1. Three floods (July 2000, August 2002, September 2003) and a hurricane (October 2001) that occurred in a lowland forest in the southern Maya Mountains of Belize presented an opportunity to evaluate the influence of these disturbances on the structure of a small mammal assemblage. 2. Four terrestrial and four primarily scansorial/arboreal species were trapped July 2000-March 2005 in six grids over 14 irregularly spaced trapping periods. 3. Community dynamics were characterized more by changes in species composition than changes in diversity. The dynamics were driven by species-specific variation in abundance, with changes in composition generally, but not exclusively, due to the occurrence or disappearance of species at low abundance. Despite the disturbances, species richness remained relatively constant. Evenness within the assemblage was consistently low, primarily as a result of dominance by one species, Heteromys desmarestianus. 4. Effects of flooding on community structure were direct but relatively brief (< 1 year), and varied with the duration and intensity of flooding. Effects from the hurricane were indirect but long-lasting and strongly related to severely reduced food resources. 5. This study suggests that long-term dynamics in the structure of many animal communities in the tropics often results from interactions between direct and indirect effects of disturbance. It also suggests that community resistance will depend on variation in disturbance type and regime, but resilience will be determined by the life-history characteristics of each species.

  10. A small scale survey of Leptospira in mammals from eastern Poland.

    PubMed

    Wójcik-Fatla, Angelina; Zając, Violetta; Sroka, Jacek; Piskorski, Michał; Cisak, Ewa; Sawczyn, Anna; Dutkiewicz, Jacek

    2013-01-01

    Samples of 30 dead small mammals each were collected on area 'A' located in eastern Poland and exposed to floods by the Vistula river, and on area 'B', also located in eastern Poland, but not exposed to floods. Kidneys and livers of the mammals were examined by the PCR and nested PCR methods for the presence of Leptospira DNA. From 7 species of small mammals examined, the presence of Leptospira DNA was detected in 2 of them. The prevalence of positive results was greatest in Apodemus agrarius which was the mostly numerous mammal species (14 out of total 39 specimens, 35.9%). The presence of Leptospira DNA was also found in Microtus arvalis (1 out of 1 specimen, 100%), whereas the remaining 5 species (Apodemus flavicollis , Apodemus sylvaticus, Microtus agrestis, Myodes glareolus, Sorex araneus) were negative. No significant difference in the prevalence of positive findings was found between the small mammals from areas 'A' exposed to flooding, compared to those from area 'B' not exposed to flooding (20.0% vs. 30.0%, p=0.3748). The overall positivity of the examined small mammals population from areas 'A' and 'B' was 25.0%. The prevalence of dual positivity (leptospiral DNA found both in kidney and liver) was greater in the mammals from areas exposed to flooding compared to those from areas not exposed to flooding (16.7% vs. 6.7%), but this dependence was also not significant (p=0.2382).

  11. Spatial distribution of an infectious disease in a small mammal community.

    PubMed

    Correa, Juana P; Bacigalupo, Antonella; Fontúrbel, Francisco E; Oda, Esteban; Cattan, Pedro E; Solari, Aldo; Botto-Mahan, Carezza

    2015-10-01

    Chagas disease is a zoonosis caused by the parasite Trypanosoma cruzi and transmitted by insect vectors to several mammals, but little is known about its spatial epidemiology. We assessed the spatial distribution of T. cruzi infection in vectors and small mammals to test if mammal infection status is related to the proximity to vector colonies. During four consecutive years we captured and georeferenced the locations of mammal species and colonies of Mepraia spinolai, a restricted-movement vector. Infection status on mammals and vectors was evaluated by molecular techniques. To examine the effect of vector colonies on mammal infection status, we constructed an infection distance index using the distance between the location of each captured mammal to each vector colony and the average T. cruzi prevalence of each vector colony, weighted by the number of colonies assessed. We collected and evaluated T. cruzi infection in 944 mammals and 1976 M. spinolai. We found a significant effect of the infection distance index in explaining their infection status, when considering all mammal species together. By examining the most abundant species separately, we found this effect only for the diurnal and gregarious rodent Octodon degus. Spatially explicit models involving the prevalence and location of infected vectors and hosts had not been reported previously for a wild disease.

  12. Spatial distribution of an infectious disease in a small mammal community

    NASA Astrophysics Data System (ADS)

    Correa, Juana P.; Bacigalupo, Antonella; Fontúrbel, Francisco E.; Oda, Esteban; Cattan, Pedro E.; Solari, Aldo; Botto-Mahan, Carezza

    2015-10-01

    Chagas disease is a zoonosis caused by the parasite Trypanosoma cruzi and transmitted by insect vectors to several mammals, but little is known about its spatial epidemiology. We assessed the spatial distribution of T. cruzi infection in vectors and small mammals to test if mammal infection status is related to the proximity to vector colonies. During four consecutive years we captured and georeferenced the locations of mammal species and colonies of Mepraia spinolai, a restricted-movement vector. Infection status on mammals and vectors was evaluated by molecular techniques. To examine the effect of vector colonies on mammal infection status, we constructed an infection distance index using the distance between the location of each captured mammal to each vector colony and the average T. cruzi prevalence of each vector colony, weighted by the number of colonies assessed. We collected and evaluated T. cruzi infection in 944 mammals and 1976 M. spinolai. We found a significant effect of the infection distance index in explaining their infection status, when considering all mammal species together. By examining the most abundant species separately, we found this effect only for the diurnal and gregarious rodent Octodon degus. Spatially explicit models involving the prevalence and location of infected vectors and hosts had not been reported previously for a wild disease.

  13. The impact of buffer strips and stream-side grazing on small mammals in southwestern Wisconsin

    USGS Publications Warehouse

    Chapman, Erik W.; Ribic, C.A.

    2002-01-01

    The practice of continuously grazing cattle along streams has caused extensive degradation of riparian habitats. Buffer strips and managed intensive rotational grazing (MIRG) have been proposed to protect and restore stream ecosystems in Wisconsin. However, the ecological implications of a switch from traditional livestock management to MIRG or buffer strip establishment have not been investigated. Differences in small mammal communities associated with riparian areas on continuously grazed and MIRG pastures, as well as vegetative buffer strips adjacent to row crops, were investigated in southwestern Wisconsin during May-September 1997 and 1998. More species (mean of 6-7) were found on the buffer sites than on the pasture sites (mean of 2-5). Total small mammal abundance on buffer sites was greater than on the pastures as well: there were 3-5 times as many animals on the buffer sites compared to the pasture sites, depending on year. There were no differences in species richness or total abundance between MIRG and continuously grazed pastures in either year. Total small mammal abundance was greater near the stream than away from the stream, regardless of farm management practice but there were no differences in species richness. Buffer strips appear to support a particularly rich and abundant small mammal community. Although results did not detect a difference in small mammal use between pasture types, farm-wide implications of a conversion from continuous to MIRG styles of grazing may benefit small mammals indirectly by causing an increase in the prevalence of pasture in the agricultural landscape.

  14. Effects of cattle grazing on small mammal communities in the Hulunber meadow steppe.

    PubMed

    Cao, Chan; Shuai, Ling-Ying; Xin, Xiao-Ping; Liu, Zhi-Tao; Song, Yan-Ling; Zeng, Zhi-Gao

    2016-01-01

    Small mammals play important roles in many ecosystems, and understanding their response to disturbances such as cattle grazing is fundamental for developing sustainable land use strategies. However, how small mammals respond to cattle grazing remains controversial. A potential cause is that most of previous studies adopt rather simple experimental designs based solely on the presence/absence of grazing, and are thus unable to detect any complex relationships between diversity and grazing intensity. In this study, we conducted manipulated experiments in the Hulunber meadow steppe to survey small mammal community structures under four levels of grazing intensities. We found dramatic changes in species composition in native small mammal communities when grazing intensity reached intermediate levels (0.46 animal unit/ha). As grazing intensity increased, Spermophilus dauricus gradually became the single dominant species. Species richness and diversity of small mammals in ungrazed and lightly grazed (0.23 animal unit/ha) area were much higher than in intermediately and heavily grazed area. We did not detect a humped relationship between small mammal diversity and disturbance levels predicted by the intermediate disturbance hypothesis (IDH). Our study highlighted the necessity of conducting manipulated experiments under multiple grazing intensities.

  15. Effects of fire on small mammal communities in frequent-fire forests in California

    USGS Publications Warehouse

    Roberts, Susan L.; Kelt, Douglas A.; Van Wagtendonk, Jan W.; Miles, A. Keith; Meyer, Marc D.

    2015-01-01

    Fire is a natural, dynamic process that is integral to maintaining ecosystem function. The reintroduction of fire (e.g., prescribed fire, managed wildfire) is a critical management tool for protecting many frequent-fire forests against stand-replacing fires while restoring an essential ecological process. Understanding the effects of fire on forests and wildlife communities is important in natural resource planning efforts. Small mammals are key components of forest food webs and essential to ecosystem function. To investigate the relationship of fire to small mammal assemblages, we live trapped small mammals in 10 burned and 10 unburned forests over 2 years in the central Sierra Nevada, California. Small mammal abundance was higher in unburned forests, largely reflecting the greater proportion of closed-canopy species such as Glaucomys sabrinus in unburned forests. The most abundant species across the entire study area was the highly adaptable generalist species, Peromyscus maniculatus. Species diversity was similar between burned and unburned forests, but burned forests were characterized by greater habitat heterogeneity and higher small mammal species evenness. The use and reintroduction of fire to maintain a matrix of burn severities, including large patches of unburned refugia, creates a heterogeneous and resilient landscape that allows for fire-sensitive species to proliferate and, as such, may help maintain key ecological functions and diverse small mammal assemblages.

  16. Effects of cattle grazing on small mammal communities in the Hulunber meadow steppe

    PubMed Central

    Xin, Xiao-Ping; Liu, Zhi-Tao; Song, Yan-Ling

    2016-01-01

    Small mammals play important roles in many ecosystems, and understanding their response to disturbances such as cattle grazing is fundamental for developing sustainable land use strategies. However, how small mammals respond to cattle grazing remains controversial. A potential cause is that most of previous studies adopt rather simple experimental designs based solely on the presence/absence of grazing, and are thus unable to detect any complex relationships between diversity and grazing intensity. In this study, we conducted manipulated experiments in the Hulunber meadow steppe to survey small mammal community structures under four levels of grazing intensities. We found dramatic changes in species composition in native small mammal communities when grazing intensity reached intermediate levels (0.46 animal unit/ha). As grazing intensity increased, Spermophilus dauricus gradually became the single dominant species. Species richness and diversity of small mammals in ungrazed and lightly grazed (0.23 animal unit/ha) area were much higher than in intermediately and heavily grazed area. We did not detect a humped relationship between small mammal diversity and disturbance levels predicted by the intermediate disturbance hypothesis (IDH). Our study highlighted the necessity of conducting manipulated experiments under multiple grazing intensities. PMID:27635323

  17. Implications of invasion by Juniperus virginiana on small mammals in the southern Great Plains

    USGS Publications Warehouse

    Horncastle, V.J.; Hellgren, E.C.; Mayer, P.M.; Ganguli, A.C.; Engle, David M.; Leslie, David M.

    2005-01-01

    Changes in landscape cover in the Great Plains are resulting from the range expansion and invasion of eastern red cedar (Juniperus virginiana). By altering the landscape and local vegetation, red cedar is changing the structure and function of habitat for small mammals. We examined effects of invasion by eastern red cedar on small mammals in 3 plant communities (tallgrass prairie, old field, and cross-timbers forest) in the cross-timbers ecoregion in Oklahoma. We sampled small mammals seasonally from May 2001 to August 2002 by using Sherman live traps and mark-recapture techniques on 3.24-ha, 450-trap grids in each plant community. We sampled vegetation in two hundred twenty-five 12 x 12-m cells within each grid. The structure of the small-mammal community differed among the 3 habitat types, with higher species diversity and richness in the tallgrass-prairie and old-field sites. Overall, the small-mammal community shifted along a gradient of increasing eastern red cedar. In the old-field and tallgrass-prairie plots, occurrence of grassland mammals decreased with increasing red cedar, whereas only 1 woodland mammal species increased. In the cross-timbers forest site, percent woody cover (<1 m in height), rather than cover of red cedar, was the most important factor affecting woodland mammal species. Examination of our data suggests that an increase in overstory cover from 0% to 30% red cedar can change a species-rich prairie community to a depauperate community dominated by 1 species, Peromyscus leucopus. Losses in species diversity and changes in mammal distribution paralleled those seen in avian communities invaded by eastern red cedar. Our results highlight ecological effects of invasion by eastern red cedar on diversity and function at multiple trophic levels. ?? 2005 American Society of Mammalogists.

  18. Alignment between values of dryland pastoralists and conservation needs for small mammals.

    PubMed

    Addison, Jane; Pavey, Chris R

    2017-04-01

    Policies for conservation outside protected areas, such as those designed to address the decline in Australian mammals, will not result in net improvements unless they address barriers to proenvironmental behavior. We used a mixed-methods approach to explore potential value-action gaps (disconnects between values and subsequent action) for small mammal conservation behaviors among pastoralists in dryland Australia. Using semistructured surveys and open-ended interviews (n = 43), we explored values toward small mammals; uptake of a range of current and intended actions that may provide benefit to small mammals; and potential perceived barriers to their uptake. Pastoralists assigned great conservation value to small mammals; over 80% (n = 36) agreed to strongly agreed that small mammals on their property were important. These values did not translate into stated willingness to engage in voluntary cessation of wild-dog control (r(2) = 0.187, p = 0.142, n = 43). However, assigning great conservation value to small mammals was strongly related to stated voluntary willingness to engage in the proenvironmental behavior most likely to result in benefits to small mammals: cat and fox control (r(2) = 0.558, p = 0.000, n = 43). There was no significant difference between stated voluntarily and incentivized willingness to engage in cat and fox control (p = 0.862, n = 43). The high levels of willingness to engage in voluntary cat and fox control highlight a potential entry point for addressing Australia's mammal declines because the engagement of pastoralists in conservation programs targeting cat and fox control is unlikely to be prevented by attitudinal constraints. Qualitative data suggest there is likely a subpopulation of pastoralists who value small mammals but do not wish to engage in formal conservation programs due to relational barriers with potential implementers. A long-term commitment to engagement with pastoralists by implementers will thus be necessary for

  19. Terrestrial outgoing radiation measurements with small satellite mission

    NASA Astrophysics Data System (ADS)

    Zhu, Ping; Dewitte, Steven; Karatekin, Ozgur; Chevalier, André; Conscience, Christian

    2015-04-01

    The solar force is the main driver of the Earth's climate. For a balanced climate system, the incoming solar radiation is equal to the sum of the reflected visible and reemitted thermal radiation at top of the atmosphere (TOA). Thus the energy imbalance plays an important role to diagnose the health of nowadays climate. However it remains a challenge to directly track the small Energy imbalance in Earth's Radiation Budget (EIERB) from space due to the complicities of the Earth's climate system and the limitation on long term stability of space instrument. The terrestrial outgoing radiation (TOR) has been recoded with a Bolometric Oscillation Sensor onboard PICAD microsatellite. In this presentation, we will report the three years TOR observed with PICARD-BOS and its further comparison with the CERES product. However the data acquired from this mission is still not enough to derive the EIERB. But the heritage gained from this experiment shields a light on the EIERB tracking with the small satellite even a cubesat mission.

  20. The Grinnell Project; Small Mammal Responses to Climate in California

    NASA Astrophysics Data System (ADS)

    Conroy, C. C.; Koo, M.; Monahan, B.; Parra, J.; Moritz, C.

    2006-12-01

    Between 1915 and 1920, Joseph Grinnell and colleagues investigated the diversity of mammals, reptiles, amphibians and birds across what they termed the Yosemite Transect, an area spanning portions of the San Joaquin Valley, the Sierra Nevada, including about 1/3 of Yosemite National Park, and ending at Mono Lake. Their data collection included preservation of series of specimens at a large number of locations, point counts of birds, photography and extensive natural history notes, all of which are still archived at the Museum of Vertebrate Zoology at UC Berkeley. Beginning in 2003, researchers from the MVZ began retracing this work, collecting specimens, using point counts, and retaking some photographs. The comparison of the two periods indicates that some mammals have shifted their ranges greatly. Most taxa show an elevation increase, either an increase at the top for middle elevation species, or a retraction at the bottom for higher elevation species. However, not all species moved, and one high elevation species moved down. To further investigate how changes observed in Yosemite might also apply to larger spatial scales, our group has been using historic climate surfaces, historic specimen localities, and a variety of modeling methods to predict statewide changes in species' distributions. Other potential sites to be revisited include the Lassen Transect in Northern California, the Colorado River, and the San Bernardino Mountains.

  1. Lower richness of small wild mammal species and chagas disease risk.

    PubMed

    Xavier, Samanta Cristina das Chagas; Roque, André Luiz Rodrigues; Lima, Valdirene dos Santos; Monteiro, Kerla Joeline Lima; Otaviano, Joel Carlos Rodrigues; Ferreira da Silva, Luiz Felipe Coutinho; Jansen, Ana Maria

    2012-01-01

    A new epidemiological scenario involving the oral transmission of Chagas disease, mainly in the Amazon basin, requires innovative control measures. Geospatial analyses of the Trypanosoma cruzi transmission cycle in the wild mammals have been scarce. We applied interpolation and map algebra methods to evaluate mammalian fauna variables related to small wild mammals and the T. cruzi infection pattern in dogs to identify hotspot areas of transmission. We also evaluated the use of dogs as sentinels of epidemiological risk of Chagas disease. Dogs (n = 649) were examined by two parasitological and three distinct serological assays. kDNA amplification was performed in patent infections, although the infection was mainly sub-patent in dogs. The distribution of T. cruzi infection in dogs was not homogeneous, ranging from 11-89% in different localities. The interpolation method and map algebra were employed to test the associations between the lower richness in mammal species and the risk of exposure of dogs to T. cruzi infection. Geospatial analysis indicated that the reduction of the mammal fauna (richness and abundance) was associated with higher parasitemia in small wild mammals and higher exposure of dogs to infection. A Generalized Linear Model (GLM) demonstrated that species richness and positive hemocultures in wild mammals were associated with T. cruzi infection in dogs. Domestic canine infection rates differed significantly between areas with and without Chagas disease outbreaks (Chi-squared test). Geospatial analysis by interpolation and map algebra methods proved to be a powerful tool in the evaluation of areas of T. cruzi transmission. Dog infection was shown to not only be an efficient indicator of reduction of wild mammalian fauna richness but to also act as a signal for the presence of small wild mammals with high parasitemia. The lower richness of small mammal species is discussed as a risk factor for the re-emergence of Chagas disease.

  2. Effect of downed woody debris on small mammal anti-predator behavior.

    SciTech Connect

    Hinkleman, Travis, M.; Orrock, John, L.; Loeb, Susan, C.

    2011-10-01

    Anti-predator behavior can affect prey growth, reproduction, survival, and generate emergent effects in food webs. Small mammals often lower the cost of predation by altering their behavior in response to shrubs,but the importance of other microhabitat features, such as downed woody debris, for anti-predator behavior is unknown. We used givingup densities to quantify the degree to which downed woody debris alters perceived predation risk by small mammals in southeastern pineforests. We placed 14 foraging trays next to large downed woody debris,shrubs, and in open areas for 12 consecutive nights. Moon illumination, a common indicator of predation risk, led to a similar reduction in small mammal foraging in all three microhabitats (open, downed woody debris,and shrub). Small mammals perceived open microhabitats as riskier than shrub microhabitats, with downed woody debris habitats perceived as being of intermediate risk between shrub and open microhabitats. Despite the presumed benefits of the protective cover of downed woody debris, small mammals may perceive downed woody debris as a relatively risky foraging site in southeastern pine forests where the high diversity and abundance of rodent-eating snakes may provide a primary predatory threat.

  3. Small mammals as biomonitors of metal pollution: a case study in Slovenia.

    PubMed

    Al Sayegh Petkovšek, Samar; Kopušar, Nataša; Kryštufek, Boris

    2014-07-01

    The transfer of lead, cadmium, zinc, mercury, copper and molybdenum from soil to the tissues of small mammals inhabiting differently polluted areas in Slovenia was investigated. Metals were determined in soil samples and in the livers of 139 individuals of five small mammal species, collected in 2012 in the vicinity of a former lead smelter, the largest Slovenian thermal power plant, along a main road and in a control area. The area in the vicinity of former lead smelter differs considerably from other study areas. The soil from that area is heavily polluted with Pb and Cd. The mean metal concentrations in the liver, irrespective of species, varied in the following ranges-Pb: 0.40-7.40 mg/kg fw and Cd: 0.27-135 mg/kg fw and reached effect concentrations at which toxic effects can be expected in a significant proportion of the livers of the small mammal specimens (Pb 40 %, Cd 67 %). These findings indicate that the majority of small mammals trapped in the area of the former lead smelter are at risk of toxic effects due to the very high bioaccumulation of Pb and Cd in the organism. On the contrary, Pd and Cd concentrations in the livers of small mammals sampled in the vicinity of the thermal power plant and along the main road were comparable with reference values and considerably lower than effect concentrations. Additionally, the study suggests that Apodemus flavicollis and Myodes glareolus are very suitable biomonitors of metal pollution.

  4. Toxoplasma gondii and Neospora caninum in wild small mammals: Seroprevalence, DNA detection and genotyping.

    PubMed

    Machačová, Tereza; Ajzenberg, Daniel; Žákovská, Alena; Sedlák, Kamil; Bártová, Eva

    2016-06-15

    Generally, rodents and other small mammals are considered as one of the sources of Toxoplasma gondii or Neospora caninum infection for cats and dogs as the definitive hosts of these two parasites, respectively. The aim of the study was to find out the prevalence of these two parasites in wild small mammals from the Czech Republic and to characterize T. gondii isolates by methods of molecular biology. A total of 621 wild small mammals were caught in the Czech Republic during years 2002-2014. Antibodies to T. gondii were detected by latex agglutination test in six (2.5%) of 240 small mammals (in two A. agrarius and four A. flavicollis). Antibodies to N. caninum were detected by commercially available competitive-inhibition enzyme-linked immunosorbent assay in one A. flavicolis (0.4%). Three of 427 (0.7%) liver samples were positive for T. gondii by PCR while negative for N. caninum. All embryo samples (n=102) were negative for both T. gondii and N. caninum. The three liver samples positive for T. gondii DNA (two from A. flavicollis and one from A. sylvaticus) were genotyped by 15 microsatellite markers and characterized as type II. To our knowledge, this is the first information about genetic characterization of T. gondii isolates in small mammals from Europe and the first detection of N. caninum antibodies in wild rodents from the Czech Republic.

  5. Small mammal distribution and diversity in a plague endemic area in West Usambara Mountains, Tanzania.

    PubMed

    Ralaizafisoloarivony, Njaka A; Kimaro, Didas N; Kihupi, Nganga I; Mulungu, Loth S; Leirs, Herwig; Msanya, Balthazar M; Deckers, Jozef A; Gulinck, Hubert

    2014-07-01

    Small mammals play a role in plague transmission as hosts in all plague endemic areas. Information on distribution and diversity of small mammals is therefore important for plague surveillance and control in such areas. The objective of this study was to investigate small mammals' diversity and their distribution in plague endemic area in the West Usambara Mountains in north-eastern Tanzania. Landsat images and field surveys were used to select trapping locations in different landscapes. Three landscapes with different habitats were selected for trapping of small mammals. Three types of trap were used in order to maximise the number of species captured. In total, 188 animals and thirteen species were captured in 4,905 trap nights. Praomys delectorum and Mastomys natalensis both reported as plague hosts comprised 50% of all the animals trapped. Trap success increased with altitude. Species diversity was higher in plantation forest followed by shrub, compared to other habitats, regardless of landscape type. It would therefore seem that chances of plague transmission from small mammals to humans are much higher under shrub, natural and plantation forest habitats.

  6. Assessing small mammal abundance with track-tube indices and mark-recapture population estimates

    USGS Publications Warehouse

    Wiewel, A.S.; Clark, W.R.; Sovada, M.A.

    2007-01-01

    We compared track-tube sampling with mark-recapture livetrapping and evaluated a track-tube index, defined as the number of track tubes with identifiable small mammal tracks during a 4-night period, as a predictor of small mammal abundance estimates in North Dakota grasslands. Meadow voles (Microtus pennsylvanicus) were the most commonly recorded species by both methods, but were underrepresented in track-tube sampling, whereas 13-lined ground squirrels (Spermophilus tridecemlineatus) and Franklin's ground squirrels (S. franklinii) were overrepresented in track-tube sampling. Estimates of average species richness were lower from track tubes than from livetrapping. Regression models revealed that the track-tube index was at best a moderately good predictor of small mammal population estimates because both the form (linear versus curvilinear) and slope of the relationship varied between years. In addition, 95% prediction intervals indicated low precision when predicting population estimates from new track-tube index observations. Track tubes required less time and expense than mark-recapture and eliminated handling of small mammals. Using track tubes along with mark-recapture in a double sampling for regression framework would have potential value when attempting to estimate abundance of small mammals over large areas. ?? 2007 American Society of Mammalogists.

  7. Sagittal spine movements of small therian mammals during asymmetrical gaits.

    PubMed

    Schilling, Nadja; Hackert, Rémi

    2006-10-01

    Mammalian locomotion is characterized by the use of asymmetrical gaits associated with extensive flexions and extensions of the body axis. Although the impact of sagittal spine movements on locomotion is well known, little information is available on the kinematics of spinal motion. Intervertebral joint movements were studied in two metatherian and three eutherian species during the gallop and halfbound using high-speed cineradiography. Fast-Fourier transformation was used to filter out high frequency digitizing errors and keep the lower frequency sinusoid oscillations that characterize the intervertebral angular movements. Independent of their regional classification as thoracic or lumbar vertebrae, 7+/-1 presacral intervertebral joints were involved in sagittal bending movements. In only one species, no more than five intervertebral joints contributed to the resulting 'pelvic movement'. In general, the trunk region involved in sagittal bending during locomotion did not correspond to the traditional subdivisions of the vertebral column (e.g. as thoracic and lumbar or pre- and postdiaphragmatic region). Therefore, these classifications do not predict the regions involved in spinal oscillations during locomotion. Independent of the gait, maximum flexion of the spine was observed in the interval between the last third of the swing phase and touch-down. This results in a retraction of the pelvis and hindlimbs before touch-down and, we hypothesize, enhances the stability of the system. Maximum extension occurred during the first third of the swing phase (i.e. after lift-off) in all species. In general, the observed timing of dorsoventral oscillations of the spine are in accordance with that observed in other mammals and with activity data of respiratory and epaxial back muscles. Although no strict craniocaudal pattern was observable, the more cranial intervertebral joints tend to flex and extend earlier than the more caudal ones. This is in accordance with the

  8. Morphometrics of the avian small intestine compared with that of nonflying mammals: a phylogenetic approach.

    PubMed

    Lavin, Shana R; Karasov, William H; Ives, Anthony R; Middleton, Kevin M; Garland, Theodore

    2008-01-01

    Flying animals may experience a selective constraint on gut volume because the energetic cost of flight increases and maneuverability decreases with greater digesta load. The small intestine is the primary site of absorption of most nutrients (e.g., carbohydrates, proteins, fat) in both birds and mammals. Therefore, we used a phylogenetically informed approach to compare small intestine morphometric measurements of birds with those of nonflying mammals and to test for effects of diet within each clade. We also compared the fit of nonphylogenetic and phylogenetic models to test for phylogenetic signal after accounting for effects of body mass, clade, and/or diet. We provide a new MATLAB program (Regressionv2.m) that facilitates a flexible model-fitting approach in comparative studies. As compared with nonflying mammals, birds had 51% less nominal small intestine surface area (area of a smooth bore tube) and 32% less volume. For animals <365 g in body mass, birds also had significantly shorter small intestines (20%-33% shorter, depending on body mass). Diet was also a significant factor explaining variation in small intestine nominal surface area of both birds and nonflying mammals, small intestine mass of mammals, and small intestine volume of both birds and nonflying mammals. On the basis of the phylogenetic trees used in our analyses, small intestine length and nominal surface area exhibited statistically significant phylogenetic signal in birds but not in mammals. Thus, for birds, related species tended to be similar in small intestine length and nominal surface area, even after accounting for relations with body mass and diet. A reduced small intestine in birds may decrease the capacity for breakdown and active absorption of nutrients. Birds do not seem to compensate for reduced digestive and absorptive capacity via a longer gut retention time of food, but we found some evidence that birds have an increased mucosal surface area via a greater villus area

  9. Control of small mammal damage in the Alberta oil sands reclamation and afforestation program

    SciTech Connect

    Radvanyi, A.

    1980-12-01

    Open-pit mining procedures being conducted in the oil sands of northeast Alberta greatly disrupt many acres of the environment. The reclamation and afforestation program intended to restore the forest habitat encountered an unanticipated problem when a large percentage of young nursery-raised trees planted on a tailings pond dyke and on overburden dump sites were found to have been girdled by a population of meadow voles which had become established in the dense grass habitat created to stabilize steep sandy slopes of the spoil piles. The study monitored small mammal populations through a high, low, and a second high level commensurate with the 3- to 4-year population cycle of small mammals. A control technique utilizing grain treated with an anticoagulant rodenticide made available to the mice in poisoned bait feeder stations effectively reduced small mammal numbers to very low levels and reduced girdling damage from an average of 50% to 1-2%.

  10. Small mammal populations at hazardous waste disposal sites near Houston, Texas, USA

    USGS Publications Warehouse

    Robbins, C.S.

    1990-01-01

    Small mammals were trapped, tagged and recaptured in 0?45 ha plots at six hazardous industrial waste disposal sites to determine if populations, body mass and age structures were different from paired control site plots. Low numbers of six species of small mammals were captured on industrial waste sites or control sites. Only populations of hispid cotton rats at industrial waste sites and control sites were large enough for comparisons. Overall population numbers, age structure, and body mass of adult male and female cotton rats were similar at industrial waste sites and control sites. Populations of small mammals (particularly hispid cotton rats) may not suffice as indicators of environments with hazardous industrial waste contamination.

  11. An inventory of terrestrial mammals at national parks in the Northeast Temperate Network and Sagamore Hill National Historic Site

    USGS Publications Warehouse

    Gilbert, Andrew T.; O'Connell, Allan F.; Annand, Elizabeth M.; Talancy, Neil W.; Sauer, John R.; Nichols, James D.

    2008-01-01

    An inventory of mammals was conducted during 2004 at nine national park sites in the Northeast Temperate Network (NETN): Acadia National Park (NP), Marsh-Billings-Rockefeller National Historical Park (NHP), Minute Man NHP, Morristown NHP, Roosevelt-Vanderbilt National Historic Site (NHS), Saint-Gaudens NHS, Saugus Iron Works NHS, Saratoga NHP, and Weir Farm NHS. Sagamore Hill NHS, part of the Northeast Coastal and Barrier Network (NCBN), was also surveyed. Each park except Acadia NP was sampled twice, once in the winter/spring and again in the summer/fall. During the winter/spring visit, indirect measure (IM) sampling arrays were employed at 2 to 16 stations and included sampling by remote cameras, cubby boxes (covered trackplates), and hair traps. IM stations were established and re-used during the summer/fall sampling period. Trapping was conducted at 2 to 12 stations at all parks except Acadia NP during the summer/fall period and consisted of arrays of small-mammal traps, squirrel-sized live traps, and some fox-sized live traps. We used estimation-based procedures and probabilistic sampling techniques to design this inventory. A total of 38 species was detected by IM sampling, trapping, and field observations. Species diversity (number of species) varied among parks, ranging from 8 to 24, with Minute Man NHP having the most species detected. Raccoon (Procyon lotor), Virginia Opossum (Didelphis virginiana), Fisher (Martes pennanti), and Domestic Cat (Felis silvestris) were the most common medium-sized mammals detected in this study and White-footed Mouse (Peromyscus leucopus), Northern Short-tailed Shrew (Blarina brevicauda), Deer Mouse (P. maniculatus), and Meadow Vole (Microtus pennsylvanicus) the most common small mammals detected. All species detected are considered fairly common throughout their range including the Fisher, which has been reintroduced in several New England states. We did not detect any state or federal endangered or threatened species.

  12. Spatial and temporal exposure patterns in non-target small mammals during brodifacoum rat control.

    PubMed

    Geduhn, Anke; Esther, Alexandra; Schenke, Detlef; Mattes, Hermann; Jacob, Jens

    2014-10-15

    Worldwide pest rodents on livestock farms are often regulated using anticoagulant rodenticides (ARs). Second generation ARs in particular can cause poisoning in non-target species due to their high toxicity and persistence. However, research on exposure of small mammals is rare. We systematically investigated spatial and temporal exposure patterns of non-target small mammals in a large-scale replicated study. Small mammals were trapped at different distances to bait stations on ten farms before, during and after brodifacoum (BR) bait application, and liver samples of 1178 non-target small mammals were analyzed for residues of eight ARs using liquid chromatography coupled with tandem mass spectrometry. BR residues were present in 23% out of 742 samples collected during and after baiting. We found clear spatial and temporal exposure patterns. High BR residue concentrations mainly occurred within 15m from bait stations. Occurrence and concentrations of residues significantly decreased with increasing distance. This pattern was found in almost all investigated taxa. After baiting, significantly more individuals contained residues than during baiting but concentrations were considerably lower. Residue occurrence and concentrations differed significantly among taxa, with the highest maximal residue concentrations in Apodemus species, which are protected in Germany. Although Sorex species are known to be insectivorous we regularly found residues in this genus. Residues of active agents other than brodifacoum were rare in all samples. The confirmation of substantial primary exposure in non-target small mammals close to the baiting area indicates considerable risk of secondary poisoning of predators, a pathway that was possibly underestimated until now. Our results will help to develop risk mitigation strategies to reduce risk for non-target small mammals, as well as their predators, in relation to biocidal AR usage.

  13. Distribution, density, and biomass of introduced small mammals in the southern mariana islands

    USGS Publications Warehouse

    Wiewel, A.S.; Adams, A.A.Y.; Rodda, G.H.

    2009-01-01

    Although it is generally accepted that introduced small mammals have detrimental effects on island ecology, our understanding of these effects is frequently limited by incomplete knowledge of small mammal distribution, density, and biomass. Such information is especially critical in the Mariana Islands, where small mammal density is inversely related to effectiveness of Brown Tree Snake (Boiga irregularis) control tools, such as mouse-attractant traps. We used mark-recapture sampling to determine introduced small mammal distribution, density, and biomass in the major habitats of Guam, Rota, Saipan, and Tinian, including grassland, Leucaena forest, and native limestone forest. Of the five species captured, Rattus diardii (sensu Robins et al. 2007) was most common across habitats and islands. In contrast, Mus musculus was rarely captured at forested sites, Suncus murinus was not captured on Rota, and R. exulans and R. norvegicus captures were uncommon. Modeling indicated that neophobia, island, sex, reproductive status, and rain amount influenced R. diardii capture probability, whereas time, island, and capture heterogeneity influenced S. murinus and M. musculus capture probability. Density and biomass were much greater on Rota, Saipan, and Tinian than on Guam, most likely a result of Brown Tree Snake predation pressure on the latter island. Rattus diardii and M. musculus density and biomass were greatest in grassland, whereas S. murinus density and biomass were greatest in Leucaena forest. The high densities documented during this research suggest that introduced small mammals (especially R. diardii) are impacting abundance and diversity of the native fauna and flora of the Mariana Islands. Further, Brown Tree Snake control and management tools that rely on mouse attractants will be less effective on Rota, Saipan, and Tinian than on Guam. If the Brown Tree Snake becomes established on these islands, high-density introduced small mammal populations will likely

  14. Elk herbivory alters small mammal assemblages in high-elevation drainages.

    PubMed

    Parsons, Elliott W R; Maron, John L; Martin, Thomas E

    2013-03-01

    Heavy herbivory by ungulates can substantially alter habitat, but the indirect consequences of habitat modification for animal assemblages that rely on that habitat are not well studied. This is a particularly important topic given that climate change can alter plant-herbivore interactions. We explored short-term responses of small mammal communities to recent exclusion of Rocky Mountain elk (Cervus elaphus) in high-elevation riparian drainages in northern Arizona, where elk impacts on vegetation have increased over the past quarter century associated with climate change. We used 10-ha elk exclosures paired with unfenced control drainages to examine how browsing influenced the habitat use, relative abundance, richness and diversity of a small mammal assemblage. We found that the small mammal assemblage changed significantly after 5 years of elk exclusion. Relative abundance of voles (Microtus mexicanus) increased in exclosure drainages, likely due to an increase in habitat quality. The relative abundances of woodrats (Neotoma neomexicana) and two species of mice (Peromyscus maniculatus and P. boylii) decreased in the controls, while remaining stable in exclosures. The decline of mice in control drainages was likely due to the decline in shrub cover that they use. Thus, elk exclusion may have maintained or improved habitat for mice inside the exclosures while habitat quality and mouse abundance both declined outside the fences. Finally, small mammal species richness increased in the exclosures relative to the controls while species diversity showed no significant trends. Together, our results show that relaxation of heavy herbivore pressure by a widespread native ungulate can lead to rapid changes in small mammal assemblages. Moreover, exclusion of large herbivores can yield rapid responses by vegetation that may enhance or maintain habitat quality for small mammal populations.

  15. Terrestrial Mammal Occupancy in the Context of Widespread Forest Loss and a Proposed Interoceanic Canal in Nicaragua's Decreasingly Remote South Caribbean Region

    PubMed Central

    Jordan, Christopher A.; Schank, Cody J.; Urquhart, Gerald R.; Dans, Armando J.

    2016-01-01

    Central America is experiencing rapid forest loss and habitat degradation both inside and outside of protected areas. Despite increasing deforestation, the Caribbean region of Nicaragua plays an important role in the survival or extinction of large mammal populations in Central America given that it still retains core areas of habitat for large mammal species. The proposed interoceanic canal project that would bisect the southern half of this Caribbean region represents a new threat that, combined with an advancing agricultural frontier, could affect populations of large mammal species such as jaguars, white-lipped peccaries, and Baird’s tapirs. We used occupancy models to examine the relative occupancy probabilities for an assemblage of terrestrial mammals in the south Caribbean region of Nicaragua to identify current core areas for our study species and conduct a preliminary evaluation of the potential impacts of the proposed interoceanic canal. We modeled a community level distribution of eight species with varying levels of sensitivity to human encroachment and a range of habitat associations. Our model results reveal three priority areas for terrestrial mammal conservation in our study area. The mapped predictions show that the only remaining area of suitable habitat for large mammals in the path of the proposed interoceanic canal is a relatively thin strip of forest that runs along the Caribbean Coast. In light of these findings, we propose five recommendations that will help ensure the conservation of this area of the proposed canal route as suitable habitat for our study species. PMID:27007122

  16. Terrestrial Mammal Occupancy in the Context of Widespread Forest Loss and a Proposed Interoceanic Canal in Nicaragua's Decreasingly Remote South Caribbean Region.

    PubMed

    Jordan, Christopher A; Schank, Cody J; Urquhart, Gerald R; Dans, Armando J

    2016-01-01

    Central America is experiencing rapid forest loss and habitat degradation both inside and outside of protected areas. Despite increasing deforestation, the Caribbean region of Nicaragua plays an important role in the survival or extinction of large mammal populations in Central America given that it still retains core areas of habitat for large mammal species. The proposed interoceanic canal project that would bisect the southern half of this Caribbean region represents a new threat that, combined with an advancing agricultural frontier, could affect populations of large mammal species such as jaguars, white-lipped peccaries, and Baird's tapirs. We used occupancy models to examine the relative occupancy probabilities for an assemblage of terrestrial mammals in the south Caribbean region of Nicaragua to identify current core areas for our study species and conduct a preliminary evaluation of the potential impacts of the proposed interoceanic canal. We modeled a community level distribution of eight species with varying levels of sensitivity to human encroachment and a range of habitat associations. Our model results reveal three priority areas for terrestrial mammal conservation in our study area. The mapped predictions show that the only remaining area of suitable habitat for large mammals in the path of the proposed interoceanic canal is a relatively thin strip of forest that runs along the Caribbean Coast. In light of these findings, we propose five recommendations that will help ensure the conservation of this area of the proposed canal route as suitable habitat for our study species.

  17. Aggregated Transfer Factors For Small Mammals Collected From the Exposed Sediments Of A 137 Cs Contaminated Reservoir

    SciTech Connect

    Paller, Michael H.; Jannika, G. Timothy; Wike, Lynn D

    2005-10-04

    {sup 137}Cs transfer factors were computed for small mammals collected from the dried sediment areas of a partially drained, contaminated reservoir. Soil {sup 137}Cs concentrations were heterogeneous on small and large spatial scales, with a geometric mean of 253.1 Bq/kg dry weight. About 50% of the variance in cotton rat Sigmodon hispidus tissue {sup 137}Cs levels was explained by variation in soil {sup 137}Cs levels. Soil to animal transfer factors (whole body dry weight) averaged 6.0 for cotton rats and 1.2 for cotton mice Peromyscus gossypinus. These values are similar to {sup 137}Cs transfer factors for herbivorous, homeothermic animals from other contaminated ecosystems. Site-specific transfer factors can significantly affect the estimation of dose. In the RESRAD-BIOTA dose model, the default transfer factor for {sup 137}Cs in terrestrial animals is 110 resulting in an estimate of radiation dose to terrestrial biota that is 16 times more than the dose calculated with the actual measured transfer factor.

  18. Influence of landscape elements on population densities and habitat use of three small-mammal species.

    SciTech Connect

    Mabry, Karen, E.; Dreelin, Erin, A.; Barrett, Gary, W.

    2003-01-01

    Mabry, K.E., E.A. Dreelin, and G.W. Barrett. 2003. Influence of landscape elements on population densities and habitat use of three small-mammal species. J. Mammology. 84(1):20-25. Corridor effects on population densities and habitat use of 3 small mammal species were assessed in an experimentally fragmented landscape. Corridor presence did not have a statistically significant effect on population densities of cotton rats or cotton mice; however, a significant effect was observed for old-field mice. The results suggest that landscape fragmentation and habitat structure may have varying effects on population densities of different species.

  19. Gamasine mite (Parasitiformes: Mesostigmata) infestations of small mammals (Mammalia: Rodentia, Insectivora) in Turkey.

    PubMed

    Cicek, Hatice; Stanyukovich, Maria; Yağci, Sukran; Aktaş, Metin; Karaer, Zafer

    2008-01-01

    The present study was conducted on small mammals from different locations in Turkey. One hundred twenty- three individuals representing 11 species of rodents and insectivora were investigated for mite ectoparasites. A total of 126 gamasine mites were collected from 96 individuals (78.1%) of 6 species of small mammals. Five gamasine families were recorded: Laelapidae, Hirstionyssidae, Haemogamasidae, Macronyssidae and Macrochelidae. Laelaps jettmari Vitzthum (72 species) was predominant and found mainly on Mus musculus (Linnaeus) and Cricetulus migratorius (Pallas). New species of gamasine mites and host records for Turkey are given.

  20. Influence of physiography and vegetation on small mammals at the Naval Petroleum Reserves, California

    SciTech Connect

    Cypher, B.L.

    1995-02-13

    Influence of physiography and vegetation on small mammal abundance and species Composition was investigated at Naval Petroleum Reserve No. 1 in California to assess prey abundance for Federally endangered San Joaquin kit foxes (Vulpes macrotis mutica) and to assess the distribution of two Federal candidate species, San Joaquin antelope squirrels (Ammospermophilus nelsoni) and short-nosed kangaroo rats (Dinodomys nitratoides brevinasus). The specific objectives of this investigation were to determine whether small mammal abundance and community composition varied with north-south orientation, terrain, ground cover, and Cypher shrub density, and whether these factors influenced the distribution and abundance of San Joaquin antelope squirrels and short-nosed kangaroo rats.

  1. Using of Synchrotron radiation for study of multielement composition of the small mammals diet and tissues

    NASA Astrophysics Data System (ADS)

    Bezel, V. S.; Koutzenogii, K. P.; Mukhacheva, S. V.; Chankina, O. V.; Savchenko, T. I.

    2007-05-01

    The Synchrotron radiation X-ray Fluorescence analysis (SRXRF) was used for estimation of "geochemical selection" of elements by small mammals, which belong to different trophic groups and inhabit polluted and background areas (the Middle Ural). The concentrations of K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Br, Rb, Sr, Y, Cd, Pb in the diet and into hepar of a herbivorous ( bank vole) and carnivorous ( Laxmann's shrew) small mammals were compared. Herbivores play a particular role in chemical elements translocation between trophic levels, limiting element transition to consumers of the consequent levels. Whereas, insectivores concentrate most elements in their tissues under the same conditions.

  2. Elevational Distribution and Ecology of Small Mammals on Tanzania's Second Highest Mountain

    PubMed Central

    Kihaule, Philip M.

    2016-01-01

    Mt. Meru is Tanzania’s second highest mountain and the ninth highest in Africa. The distribution and abundance of small mammals on this massif are poorly known. Here we document the distribution of shrews and rodents along an elevational gradient on the southeastern versant of Mt. Meru. Five sites were sampled with elevational center points of 1950, 2300, 2650, 3000, and 3600 m, using a systematic methodology of standard traps and pitfall lines, to inventory the shrews and rodents of the slope. Ten species of mammal were recorded, comprising 2 shrew and 8 rodent species with the greatest diversity for each group at 2300 m. No species previously unrecorded on Mt. Meru was observed. Two rodent genera that occur in nearby Eastern Arc Mountains (Hylomyscus and Beamys) were not recorded. The rodent Lophuromys verhageni and a recently described species of shrew, Crocidura newmarki, are the only endemic mammals on Mt. Meru, and were widespread across the elevational gradient. As in similar small mammal surveys on other mountains of Tanzania, rainfall positively influenced trap success rates for shrews, but not for rodents. This study provides new information on the local small mammal fauna of the massif, but numerous other questions remain to be explored. Comparisons are made to similar surveys of other mountains in Tanzania. PMID:27653635

  3. Elevational Distribution and Ecology of Small Mammals on Tanzania's Second Highest Mountain.

    PubMed

    Stanley, William T; Kihaule, Philip M

    Mt. Meru is Tanzania's second highest mountain and the ninth highest in Africa. The distribution and abundance of small mammals on this massif are poorly known. Here we document the distribution of shrews and rodents along an elevational gradient on the southeastern versant of Mt. Meru. Five sites were sampled with elevational center points of 1950, 2300, 2650, 3000, and 3600 m, using a systematic methodology of standard traps and pitfall lines, to inventory the shrews and rodents of the slope. Ten species of mammal were recorded, comprising 2 shrew and 8 rodent species with the greatest diversity for each group at 2300 m. No species previously unrecorded on Mt. Meru was observed. Two rodent genera that occur in nearby Eastern Arc Mountains (Hylomyscus and Beamys) were not recorded. The rodent Lophuromys verhageni and a recently described species of shrew, Crocidura newmarki, are the only endemic mammals on Mt. Meru, and were widespread across the elevational gradient. As in similar small mammal surveys on other mountains of Tanzania, rainfall positively influenced trap success rates for shrews, but not for rodents. This study provides new information on the local small mammal fauna of the massif, but numerous other questions remain to be explored. Comparisons are made to similar surveys of other mountains in Tanzania.

  4. Small mammal tooth enamel carbon isotope record of C4 grasses in late Neogene China

    NASA Astrophysics Data System (ADS)

    Arppe, Laura; Kaakinen, Anu; Passey, Benjamin H.; Zhang, Zhaoqun; Fortelius, Mikael

    2015-10-01

    The spatiotemporal pattern of the late Cenozoic spread of C4 vegetation is an important indicator of environmental change that is intertwined with the uplift of the Himalaya and Tibetan Plateau, and the development of the East Asian monsoons. To explore the spread of C4 vegetation in China and shed new light on regional climatic evolution, we measured δ13C values of more than 200 small mammal teeth (primarily rodents and lagomorphs) using a laser ablation isotope ratio mass spectrometry approach. Small mammals are highly sensitive indicators of their environment because they have limited spatial ranges and because they have minimal time-averaging of carbon isotope signatures of dietary components. The specimens originate from four classic Late Miocene fossil localities, Lufeng, Yuanmou, Lingtai, and Ertemte, along a southwest-northeast transect from Yunnan Province to Inner Mongolia. In Yunnan (Lufeng, Yuanmou) and on the Loess Plateau (Lingtai), the small mammal δ13C values record nearly pure C3 ecosystems, and mixed but C3-based ecosystems, respectively, in agreement with previous studies based on carbon isotopes of large herbivores and soil carbonates. In Inner Mongolia, the micromammalian tooth enamel δ13C record picks up the presence of C4 vegetation where large mammal samples do not, indicating a mixed yet C3-dominated ecosystem at ~ 6 Ma. As a whole, the results support a scenario of northward increasing C4 grass abundance in a pattern that mirrors northward decreasing precipitation of the summer monsoon system. The results highlight differences between large and small mammals as indicators of C4 vegetation in ancient ecosystems, particularly the ability of small mammal δ13C values to detect the presence of minor components of the vegetation structure.

  5. Terrestrial matter effects on reactor antineutrino oscillations at JUNO or RENO-50: how small is small?

    NASA Astrophysics Data System (ADS)

    Li, Yu-feng; Wang, Yi-fang; Xing, Zhi-zhong

    2016-09-01

    We have carefully examined, in both analytical and numerical ways, how small the terrestrial matter effects can be in a given medium-baseline reactor antineutrino oscillation experiment like JUNO or RENO-50. Taking the forthcoming JUNO experiment as an example, we show that the inclusion of terrestrial matter effects may reduce the sensitivity of the neutrino mass ordering measurement by and a neglect of such effects may shift the best-fit values of the flavor mixing angle θ12 and the neutrino mass-squared difference Δ21 by about 1σ to 2σ in the future data analysis. In addition, a preliminary estimate indicates that a 2σ sensitivity of establishing the terrestrial matter effects can be achieved for about 10 years of data taking at JUNO with the help of a suitable near detector implementation. Supported by National Natural Science Foundation of China (11135009, 11305193), the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA10010100) and the CAS Center for Excellence in Particle Physics

  6. THE subfossil occurrence and paleoecological significance of small mammals at ankilitelo cave, southwestern Madagascar

    USGS Publications Warehouse

    Muldoon, K.M.; De Blieux, D. D.; Simons, E.L.; Chatrath, P.S.

    2009-01-01

    Small mammals are rarely reported from subfossil sites in Madagascar despite their importance for paleoenvironmental reconstruction, especially as it relates to recent ecological changes on the island. We describe the uniquely rich subfossil small mammal fauna from Ankilitelo Cave, southwestern Madagascar. The Ankilitelo fauna is dated to the late Holocene (???500 years ago), documenting the youngest appearances of the extinct giant lemur taxa Palaeopropithecus, Megaladapis, and Archaeolemur, in association with abundant remains of small vertebrates, including bats, tenrecs, carnivorans, rodents, and primates. The Ankilitelo fauna is composed of 34 mammalian species, making it one of the most diverse Holocene assemblages in Madagascar. The fauna comprises the 1 st report of the short-tailed shrew tenrec (Microgale brevicaudata) and the ring-tailed mongoose (Galidia elegans) in southwestern Madagascar. Further, Ankilitelo documents the presence of southwestern species that are rare or that have greatly restricted ranges today, such as Nasolo's shrew tenrec (M. nasoloi), Grandidier's mongoose (Galidictis grandidieri), the narrow-striped mongoose (Mungotictis decemlineata), and the giant jumping rat (Hypogeomys antimena). A simple cause for the unusual small mammal occurrences at Ankilitelo is not obvious. Synergistic interactions between climate change, recent fragmentation and human-initiated degradation of forested habitats, and community-level processes, such as predation, most likely explain the disjunct distributions of the small mammals documented at Ankilitelo. ?? 2009 American Society of Mammalogists.

  7. Small mammals in a fragment and adjacent matrix in southeastern Brazil.

    PubMed

    Passamani, M; Ribeiro, D

    2009-05-01

    Between May 2002 and May 2003, we studied a small mammal community from an Atlantic forest fragment surrounded by a coffee plantation in the municipality of Santa Teresa, Espírito Santo state, Brazil. We obtained a total of 300 captures of 114 individuals belonging to 11 mammal species. Seventy three percent of the species captured in the forest also used the coffee plantation, mainly males (90%) and young (80%) individuals of Marmosops incanus. The exceptionally low recapture rate in the coffee plantation suggests that it functions as a corridor between fragments, rather than as a habitat for these species. Understanding the role of matrix habitat use in fragmented landscapes is an important factor in small mammal conservation, as it asymmetrically affects the rate and mode of individual movements of different species.

  8. 50 CFR 18.27 - Regulations governing small takes of marine mammals incidental to specified activities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... specified activity (other than commercial fishing) within a specified geographical region. (b) Scope of... specified geographical region and potentially involves the taking of small numbers of marine mammals. The specified activity and specified geographical region should be identified so that the anticipated effects...

  9. IMPLICATIONS OF INVASION BY JUNIPERUS VIRGINIANA ON SMALL MAMMALS IN THE SOUTHERN GREAT PLAINS

    EPA Science Inventory

    Changes in landscape cover in the Great Plains are resulting from the range expansion and invasion of eastern red cedar (Juniperus virginiana). By altering the landscape and local vegetation, red cedar is changing the structure and function of habitat for small mammals. We exam...

  10. THE INTERACTION OF HABITAT FRAGMENTATION, PLANT, AND SMALL MAMMAL SUCCESSION IN AN OLD FIELD

    EPA Science Inventory

    We compared the density and spatial distribution of four small mammal species (Microtus ochrogaster, Peromyscus maniculatus, Sigmodon hispidus, and P. luecopus) along with general measures of an old field plant community across two successional phases (1984-1986 and 1994-1996) of...

  11. Cattle grazing and small mammals on the Sheldon National Wildlife Refuge, Nevada

    USGS Publications Warehouse

    Oldemeyer, John L.; Allen-Johnson, L. R.

    1988-01-01

    We studied effects of cattle grazing on small mammal microhabitat and abundance in northwestern Nevada. Abundance, diversity, and microhabitat were compared between a 375-ha cattle exclosure and a deferred-rotation grazing allotment which had a three-year history of light to moderate use. No consistent differences were found in abundance, diversity, or microhabitat between the two areas.

  12. IIMPLICATIONS OF INVASION BY JUNIPERUS VIRGINIANA ON SMALL MAMMALS IN THE SOUTHERN GREAT PLAINS

    EPA Science Inventory

    Changes in landscape cover in the Great Plains are resulting from the range expansion and invasion of eastern red cedar (Juniperus virginiana). By altering the landscape and local vegetation, red cedar is changing the structure and function of habitat for small mammals. We examin...

  13. Effects of bridge construction on songbirds and small mammals at Blennerhassett Island, Ohio River, USA.

    PubMed

    Vance, Joshua A; Angus, Norse B; Anderson, James T

    2013-09-01

    Construction of man-made objects such as roads and bridges may have impacts on wildlife depending on species or location. We investigated songbirds and small mammals along the Ohio River, WV, USA at a new bridge both before and after construction and at a bridge crossing that was present throughout the study. Comparisons were made at each site over three time periods (1985-1987 [Phase I] and 1998-2000 [Phase II] [pre-construction], 2007-2009 [Phase III] [post-construction]) and at three distances (0, 100, 300 m) from the bridge or proposed bridge location. Overall, 70 songbirds and 10 small mammals were detected during the study. Cliff swallows (Petrochelidon pyrrhonota) and rock pigeons (Columba livia) showed high affinity for bridges (P < 0.05). Combined small mammal abundances increased between Phases I and II (P < 0.05), but did not differ between Phases II and III (P > 0.05). Species richness and diversity for songbirds and small mammals did not differ before and after bridge construction (P > 0.05). We found that most species sampled did not respond to the bridge crossing, and believe that the bridge is not causing any measurable negative density impacts to the species we investigated. The new bridge does provide habitat for exotic rock pigeons that are adjusted to man-made structures for nesting.

  14. NITROGEN OUTPUTS FROM FECAL AND URINE DEPOSITION OF SMALL MAMMALS: IMPLICATIONS FOR NITROGEN CYCLING

    EPA Science Inventory

    The contribution of small mammals to nitrogen cycling is poorly understood, but it could have reverberations back to the producer community by maintaining or perhaps magnifying nitrogen availability. Our objective was to model nitrogen outputs (deposition of feces and urine) of ...

  15. Vegetation habitats and small mammals in a plague endemic area in Western Usambara Mountains, Tanzania.

    PubMed

    Ralaizafisoloarivony, Njaka A; Kimaro, Didas N; Kihupi, Nganga I; Mulungu, Loth S; Leirs, Herwig; Msanya, Balthazar M; Deckers, Jozef A; Gulinck, Hubert

    2014-07-01

    Human plague still exists in different parts of the world, including some landscapes in north-eastern Tanzania. Wherever the hotspot of plague, small mammals seem to play a key role as host. The objective of this study was to investigate the relationship between vegetation habitats types and small mammals in a plague endemic area of Lushoto District in Tanzania. A combination of field survey and Landsat images was used to identify the vegetation habitats. Small mammals were trapped in the mapped vegetation units, and identified. In total, six main types of vegetation habitats were investigated. A total of 13 small mammal species, potentially related to plague were trapped. Results show that annual cultivated crops habitat accounted for 80% of Mastomys natalensis while natural forest accounted for 60% of Praomys delectorum. These findings have shed new light on the diversity of rodents in different habitats of natural and semi-natural vegetations, and agricultural crops in the study area, which is an important intermediate step in unravelling the complex human plague system.

  16. Road network in an agrarian landscape: Potential habitat, corridor or barrier for small mammals?

    NASA Astrophysics Data System (ADS)

    Redon (de), Louis; Le Viol, Isabelle; Jiguet, Frédéric; Machon, Nathalie; Scher, Olivier; Kerbiriou, Christian

    2015-01-01

    If the negative effects of road networks on biodiversity are now recognized, their role as barriers, habitats or corridors remain to be clarified in human altered landscapes in which road verges often constitute the few semi-natural habitats where a part of biodiversity important for ecosystem functioning may maintain. In human-dominated landscape, their roles are crucial to precise in comparison to other habitats for small mammal species considered as major natural actors (pests (voles) or biological control agents (shrew)). We studied these roles through the comparison of small mammal abundance captured (418 individuals belonging to 8 species) using non-attractive pitfall traps (n = 813) in 176 sampled sites distributed in marginal zones of road and crop, in natural areas and in fields. We examined the effect of roadside width and isolation of sites. We found the higher small mammal abundances in roadside verges and an effect of width margins for shrews. The significant effect of the distance to the next adjacent natural habitat at the same side of the road on the relative abundance of Sorex coronatus, and the absence of a significant effect of distance to the next natural habitat at the opposite side of road, suggest that highway and road verges could be used as corridor for their dispersal, but have also a barrier effect for shrews. Our results show that in intensive agricultural landscapes roadside and highway verges may often serve as refuge, habitat and corridor for small mammals depending on species and margin characteristics.

  17. 50 CFR 18.27 - Regulations governing small takes of marine mammals incidental to specified activities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the species or stock through effects on annual rates of recruitment or survival. Small numbers means a... specified activity and specified geographical region should be identified so that the anticipated effects on... information; (A) An estimate of the species and numbers of marine mammals likely to be taken by age, sex,...

  18. Small mammals in saltcedar (Tamarix ramosissima) - invaded and native riparian habitats of the western Great Basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Invasive saltcedar species have replaced native riparian trees on numerous river systems throughout the western US, raising concerns about how this habitat conversion may affect wildlife. For periods ranging from 1-10 years, small mammal populations were monitored at six riparian sites impacted by s...

  19. Organochlorine pesticides and polychlorinated biphenyl congeners in wild terrestrial mammals from Croatia: Interspecies comparison of residue levels and compositions.

    PubMed

    Herceg Romanić, Snježana; Klinčić, Darija; Kljaković-Gašpić, Zorana; Kusak, Josip; Reljić, Slaven; Huber, Đuro

    2015-10-01

    In this pilot study, we investigated levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in the adipose tissues of two free-ranging terrestrial carnivores from Croatia sampled in 2010 and 2011: the brown bear (Ursus arctos; N=32) and the grey wolf (Canis lupus; N=29). Concentrations of ∑OCPs and ΣPCBs ranged from 0.45 to 4.09 ng g(-1) lipid mass (lm) and from 0.93 to 8.52 ng g(-1) lm in brown bear, and from 1.18 to 5.67 ng g(-1) lm and 2.68 to 48.9 ng g(-1) lm in grey wolf adipose tissues, respectively. PCBs were dominant accounting for over 72% of total analyzed persistent organic pollutants (POPs). The sum of six indicator non-dioxin-like PCBs (Σ6IndNDL PCBs) made up 60-93% and 58-85% of the total congener concentrations in brown bears and wolves, respectively. Although the levels of the measured parameters were significantly higher in grey wolves than in bears, the contaminant profiles of the two species were similar, with γ-HCH, HCB, β-HCH and DDE as major OCP contaminants, and PCB-153>PCB-180≈PCB-170>PCB-138 as the dominant congeners. The sum of hexachlorocyclohexanes (ΣHCHs) and 8 toxicologically relevant dioxin-like PCBs (Σ8ToxDL PCBs) was higher in the males than in the females of the brown bear. Concentrations of ΣDDTs, HCB, ΣOCP, ΣPCBs, Σ6IndNDL PCBs, and toxicologically relevant non-dioxin-like PCBs (ΣToxNDL PCBs) were significantly positively correlated with lipid content in the grey wolf. Concentrations of OCPs and PCBs in brown bears and wolves from Croatia were low and normal for large terrestrial mammals.

  20. Species distribution of staphylococci from small wild mammals.

    PubMed

    Hauschild, Tomasz; Sliżewski, Piotr; Masiewicz, Paweł

    2010-12-01

    A total of 197 isolates of Staphylococcus from small wild animals (insectivores and rodents) were identified by partial sequencing of the rpoB and dnaJ genes. Among the identified isolates the predominant species was S. succinus (28%), followed by S. xylosus (20.8%) and S. stepanovicii (18.3%). The other 14 Staphylococcus species were occasionally isolated. PCR-RFLP of the rpoB gene digested by Hpy8I was a fast and simple method to distinguish the two subspecies of S. succinus. More than 90% of the 55 S. succinus strains isolated belonged to S. succinus subsp. casei and only 9% to S. succinus subsp. succinus. Moreover, the present study describes the first ever isolation of S. fleurettii from healthy animals.

  1. Community occupancy responses of small mammals to restoration treatments in ponderosa pine forests, northern Arizona, USA.

    PubMed

    Kalies, E L; Dickson, B G; Chambers, C L; Covington, W W

    2012-01-01

    In western North American conifer forests, wildfires are increasing in frequency and severity due to heavy fuel loads that have accumulated after a century of fire suppression. Forest restoration treatments (e.g., thinning and/or burning) are being designed and implemented at large spatial and temporal scales in an effort to reduce fire risk and restore forest structure and function. In ponderosa pine (Pinus ponderosa) forests, predominantly open forest structure and a frequent, low-severity fire regime constituted the evolutionary environment for wildlife that persisted for thousands of years. Small mammals are important in forest ecosystems as prey and in affecting primary production and decomposition. During 2006-2009, we trapped eight species of small mammals at 294 sites in northern Arizona and used occupancy modeling to determine community responses to thinning and habitat features. The most important covariates in predicting small mammal occupancy were understory vegetation cover, large snags, and treatment. Our analysis identified two generalist species found at relatively high occupancy rates across all sites, four open-forest species that responded positively to treatment, and two dense-forest species that responded negatively to treatment unless specific habitat features were retained. Our results indicate that all eight small mammal species can benefit from restoration treatments, particularly if aspects of their evolutionary environment (e.g., large trees, snags, woody debris) are restored. The occupancy modeling approach we used resulted in precise species-level estimates of occupancy in response to habitat attributes for a greater number of small mammal species than in other comparable studies. We recommend our approach for other studies faced with high variability and broad spatial and temporal scales in assessing impacts of treatments or habitat alteration on wildlife species. Moreover, since forest planning efforts are increasingly focusing on

  2. High prevalence of Rickettsia spp. infections in small mammals in Taiwan.

    PubMed

    Kuo, Chi-Chien; Shu, Pei-Yun; Mu, Jung-Jung; Wang, Hsi-Chieh

    2015-01-01

    Surveillance for Rickettsia spp. is urgently needed due to the recent emergence of many novel rickettsioses around the globe, but previous studies in Taiwan have been limited to small areas and no investigation of infections in vertebrate hosts has ever been attempted. We surveyed rickettsial infections systematically in small-mammal hosts trapped between 2006 and 2010 throughout Taiwan. Fragments of ompB and gltA genes in the liver, spleen, and kidney of mammals were targeted by nested polymerase chain reaction. We trapped 1375 individuals of 10 species, among which Rattus losea was the most common (54.6%), followed by Suncus murinus (20.6%) and Mus caroli (10.6%). The overall rate of Rickettsia infections in the liver, spleen, or kidney of 309 assayed small mammals was 60.5%, with a rate of infection ≥50% for each mammal species. DNA nucleotide sequences of 184 successfully sequenced genes were most similar to nine Rickettsia species: Rickettsia conorii, R. felis, R. japonica, R. raoultii, R. rickettsii, Rickettsia sp. IG-1, Rickettsia sp. TwKM01, Rickettsia sp. TwKM02, and R. typhi. Our results suggest that several novel Rickettsia spp. are common and widespread across various habitats throughout Taiwan and suggest the need for further study of emerging rickettsioses in Taiwan.

  3. Conservation on International Boundaries: The Impact of Security Barriers on Selected Terrestrial Mammals in Four Protected Areas in Arizona, USA

    PubMed Central

    McCallum, Jamie W.; Rowcliffe, J. Marcus; Cuthill, Innes C.

    2014-01-01

    Several thousand terrestrial protected areas (PAs) lie on international boundaries. Because international boundaries can be focal points for trade, illegal activity and development, such PAs can be vulnerable to a range of anthropogenic threats. There is an increasing trend towards the erection of international boundary infrastructure (including fences, barriers and ditches) in many parts of the world, which may reduce the risk of these anthropogenic threats to some PAs. However this may restrict home range and access to resources for some native species. We sought to understand the impacts of these two different types of threat by using camera traps to measure the activity level of humans, native and invasive mammals in four US PAs on the Mexican international boundary. Comparisons were made between treatment areas with barriers and those without. Results showed that puma and coati were more likely to appear in treatment areas without barriers, whereas humans were not observed more frequently in one treatment area over another. The suggestion is that the intermittent fencing present in this part of the world does affect some native species, but does not necessarily restrict the movement of humans (including illegal migrants), who may negatively impact native species. PMID:24717982

  4. Trends in North American small mammals found in common barn-owl (Tyto alba) dietary studies

    USGS Publications Warehouse

    Clark, D.R.; Bunck, C.M.

    1991-01-01

    Data on mammals were compiled from published studies of common barn-owl (Tyto alba) pellets. Mammalian composition of pellet samples was analyzed within geographic regions in regard to year, mean annual precipitation, latitude, and number of individual mammals in the sample. Percentages of individuals in pellets that were shrews increased whereas the percentages of rodents decreased with greater mean annual precipitation, especially in northern and western areas of North America. From the 1920s through 1980s, in northern and eastern areas the percentage of species that was shrews decreased, and in northern and central areas the percentage of individuals that was murid rats and mice increased. Human alterations of habitats during these seven decades are postulated to have caused changes in available small mammals, leading to changes in the barn-owl diet.

  5. Bomb radiocarbon in metabolically inert tissues from terrestrial and marine mammals

    SciTech Connect

    Bada, J.L.; Vrolijk, C.D.; Brown, S.; Druffel, E.R.M.; Hedges, R.E.M.

    1987-10-01

    We report here radiocarbon measurements of monkey eye lens nucleus proteins and a narwhal tusk, biological tissues which have sampled the bomb radiocarbon signal in different ways. The results confirm the metabolic inertness of eye lens nucleus proteins and demonstrate the feasibility of measuring radiocarbon in small samples of biological tissue using accelerator mass spectrometry (AMS). The narwhal tusk provides a unique record of the radiocarbon activity in Arctic Ocean waters over most of the 20th century.

  6. Predicting small mammal and flea abundance using landform and soil properties in a plague endemic area in Lushoto District, Tanzania.

    PubMed

    Meliyo, Joel L; Kimaro, Didas N; Msanya, Balthazar M; Mulungu, Loth S; Hieronimo, Proches; Kihupi, Nganga I; Gulinck, Hubert; Deckers, Jozef A

    2014-07-01

    Small mammals particularly rodents, are considered the primary natural hosts of plague. Literature suggests that plague persistence in natural foci has a root cause in soils. The objective of this study was to investigate the relationship between on the one hand landforms and associated soil properties, and on the other hand small mammals and fleas in West Usambara Mountains in Tanzania, a plague endemic area. Standard field survey methods coupled with Geographical Information System (GIS) technique were used to examine landform and soils characteristics. Soil samples were analysed in the laboratory for physico-chemical properties. Small mammals were trapped on pre-established landform positions and identified to genus/species level. Fleas were removed from the trapped small mammals and counted. Exploration of landform and soil data was done using ArcGIS Toolbox functions and descriptive statistical analysis. The relationships between landforms, soils, small mammals and fleas were established by generalised linear regression model (GLM) operated in R statistics software. Results show that landforms and soils influence the abundance of small mammals and fleas and their spatial distribution. The abundance of small mammals and fleas increased with increase in elevation. Small mammal species richness also increases with elevation. A landform-soil model shows that available phosphorus, slope aspect and elevation were statistically significant predictors explaining richness and abundance of small mammals. Fleas' abundance and spatial distribution were influenced by hill-shade, available phosphorus and base saturation. The study suggests that landforms and soils have a strong influence on the richness and evenness of small mammals and their fleas' abundance hence could be used to explain plague dynamics in the area.

  7. The impacts of Cenozoic climate and habitat changes on small mammal diversity of North America

    NASA Astrophysics Data System (ADS)

    Samuels, Joshua X.; Hopkins, Samantha S. B.

    2017-02-01

    millions of years earlier than in larger mammals. This is likely a consequence of the smaller mammals' greater sensitivity to environmental changes and more rapid evolution. These results highlight the importance of examining understudied members of vertebrate faunas for understanding the evolution of terrestrial communities through time.

  8. Arboreal locomotion in Eurasian harvest mice Micromys Minutus (Rodentia: Muridae): The gaits of small mammals.

    PubMed

    Karantanis, Nikolaos-Evangelos; Rychlik, Leszek; Herrel, Anthony; Youlatos, Dionisios

    2017-03-23

    Body size imposes significant constraints on arboreal locomotion. Despite the wealth of research in larger arboreal mammals, there is a lack of data on arboreal gaits of small mammals. In this context, the present study explores arboreal locomotion in one of the smallest rodents, the Eurasian harvest mice Micromys minutus (∼10 g). We examined gait metrics (i.e., diagonality, duty factor [DF], DF index, velocity, stride length, and stride frequency) of six adult male mice on simulated arboreal substrates of different sizes (2, 5, 10, and 25 mm) and inclinations (0(0) and 45(0) ). Micromys minutus employed slow, lateral sequence symmetrical gaits on the smaller substrates, which shifted to progressively faster symmetrical gaits of higher diagonality on larger substrates. Both ascents and descents were associated with a higher diagonality, and ascents with a higher DF index compared to horizontal locomotion, underscoring the role of the grasping hind feet. Velocity increase was brought about primarily by an increase in stride frequency, a pattern often encountered in other small mammals, with a secondary and significant contribution of stride length. These findings indicate that, except for velocity and the way it is regulated, there are no significant differences in gait metrics between larger and smaller arboreal mammals. Moreover, the locomotor adaptations of Eurasian harvest mice represent behavioral mechanisms that promote stable, safe, and continuous navigation along slender substrates and ultimately contribute to the successful exploitation of the arboreal milieu.

  9. A trait-based approach for predicting species responses to environmental change from sparse data: how well might terrestrial mammals track climate change?

    PubMed

    Santini, Luca; Cornulier, Thomas; Bullock, James M; Palmer, Stephen C F; White, Steven M; Hodgson, Jenny A; Bocedi, Greta; Travis, Justin M J

    2016-07-01

    Estimating population spread rates across multiple species is vital for projecting biodiversity responses to climate change. A major challenge is to parameterise spread models for many species. We introduce an approach that addresses this challenge, coupling a trait-based analysis with spatial population modelling to project spread rates for 15 000 virtual mammals with life histories that reflect those seen in the real world. Covariances among life-history traits are estimated from an extensive terrestrial mammal data set using Bayesian inference. We elucidate the relative roles of different life-history traits in driving modelled spread rates, demonstrating that any one alone will be a poor predictor. We also estimate that around 30% of mammal species have potential spread rates slower than the global mean velocity of climate change. This novel trait-space-demographic modelling approach has broad applicability for tackling many key ecological questions for which we have the models but are hindered by data availability.

  10. Energy flow and functional compensation in Great Basin small mammals under natural and anthropogenic environmental change

    PubMed Central

    Terry, Rebecca C.; Rowe, Rebecca J.

    2015-01-01

    Research on the ecological impacts of environmental change has primarily focused at the species level, leaving the responses of ecosystem-level properties like energy flow poorly understood. This is especially so over millennial timescales inaccessible to direct observation. Here we examine how energy flow within a Great Basin small mammal community responded to climate-driven environmental change during the past 12,800 y, and use this baseline to evaluate responses observed during the past century. Our analyses reveal marked stability in energy flow during rapid climatic warming at the terminal Pleistocene despite dramatic turnover in the distribution of mammalian body sizes and habitat-associated functional groups. Functional group turnover was strongly correlated with climate-driven changes in regional vegetation, with climate and vegetation change preceding energetic shifts in the small mammal community. In contrast, the past century has witnessed a substantial reduction in energy flow caused by an increase in energetic dominance of small-bodied species with an affinity for closed grass habitats. This suggests that modern changes in land cover caused by anthropogenic activities—particularly the spread of nonnative annual grasslands—has led to a breakdown in the compensatory dynamics of energy flow. Human activities are thus modifying the small mammal community in ways that differ from climate-driven expectations, resulting in an energetically novel ecosystem. Our study illustrates the need to integrate across ecological and temporal scales to provide robust insights for long-term conservation and management. PMID:26170294

  11. Small mammal carbon isotope ecology across the Miocene-Pliocene boundary, northwestern Argentina

    NASA Astrophysics Data System (ADS)

    Hynek, Scott A.; Passey, Benjamin H.; Prado, José Luis; Brown, Francis H.; Cerling, Thure E.; Quade, Jay

    2012-03-01

    The late Miocene expansion of plants using the C4 photosynthetic pathway in South America has been documented by tooth enamel carbon isotope ratios (δ13Cen). However, a more detailed understanding of this ecological event is hampered by poor chronological control on the widespread fossil localities from which isotopic data are derived. This study develops a δ13Cen record from a single 2500 m-thick stratigraphic section in subtropical South America. Strata at Puerta de Corral Quemado (PCQ), northwestern Argentina, span 9 to 3.5 Ma in age, and existing paleosol carbonate data (δ13Cpc) document C4 expansion across the Miocene-Pliocene boundary. Comparison of δ13Cen data with δ13Cpc data at high stratigraphic resolution refines understanding of this ecological event in South America. Small mammal δ13Cen data in particular are complementary to that of large mammal and paleosol δ13C data. Small mammal teeth integrate isotopic data over much shorter temporal and spatial scales than large mammal teeth, providing a sensitive measure of local vegetation and placing constraints on the landscape distribution of C3 and C4 plants. Explicit consideration of the distinctive carbon isotope enrichment factor between enamel and diet for rodents (ɛ*en-diet = 11‰, as opposed to 14‰ for large mammals) allows for unequivocal inference of C4 vegetation ~ 1 Ma prior to that inferred from large mammal δ13Cen data, and ~ 2 Ma prior to δ13Cpc data. This multiproxy record demonstrates that C4 plants were a stable component of the ecosystem hundreds of thousands of years prior to their major ecological expansion, and that the expansion of C4 plants was pulsed at PCQ. Two periods of ecological change are demonstrated by δ13C and δ18O data at ~ 7 Ma and 5.3 Ma (coincident with the Miocene-Pliocene boundary). Development of small mammal δ13Cen records on other continents may provide similar insight into the early stages of the global C4 event.

  12. The importance of lizards and small mammals as reservoirs for Borrelia lusitaniae in Portugal.

    PubMed

    Norte, Ana Cláudia; Alves da Silva, António; Alves, Joana; da Silva, Luís Pascoal; Núncio, M Sofia; Escudero, Raquel; Anda, Pedro; Ramos, Jaime A; Lopes de Carvalho, Isabel

    2015-04-01

    Borrelia lusitaniae is a pathogen frequent in the Mediterranean area. Apart from lizards, evidence for birds and small mammals as competent reservoirs for this genospecies has been occasional. We collected questing ticks, skin biopsies and Ixodes sp. ticks feeding on lizards, birds and small mammals in a B. burgdorferi s.l. (sensu lato) enzootic area to assess their importance in the maintenance of B. lusitaniae. Borrelia lusitaniae was the most prevalent genospecies in questing ticks and was commonly found in larvae feeding on Psammodromus algirus. One biopsy infected with B. lusitaniae was collected from the tail of one Podarcis hispanica, which suggests systemic infection. Ixodes ricinus larvae feeding on Apodemus sylvaticus were infected with B. lusitaniae but with a lower prevalence. Our results reinforce the importance of lizards as reservoirs for B. lusitaniae, suggesting that P. algirus, in particular, acts as main reservoir for B. lusitaniae in Portugal.

  13. [The gamasid mites (Parasitiformes: Mesostigmata) of small mammals from undeveloped land in Moscow].

    PubMed

    Lopatina, Iu V; Petrova, A D; Timoshkov, V V

    1998-01-01

    On 11 species of small mammals collected in the parks and ruderal areas of Moscow in 1964-1991, 35 species of mites were revealed. Among them 23 species were parasitic. Laelaps hilaris, Haemogamasus nidi, and Androlaelaps glasgowi were predominant. The mite species diversity on small mammals in Moscow is similar to that in natural environments. The epidemiological and epizootiological significance of revealed species of mites is discussed. The rat mite Ornithonyssus bacoti has the major medical importance as the pathogen of the rat mite dermatitis in Moscow and as a vector of transmissive diseases. According to literature and the data obtained the favorable conditions for maintenance of transmissive diseases reservoirs exist permanently in Moscow.

  14. Radionuclide contaminant analysis of small mammals at Area G, TA-54, 1994

    SciTech Connect

    Biggs, J.; Bennett, K.; Fresquez, P.

    1995-09-01

    Small mammals were sampled at two waste burial sites (1 and 2) at Area G, TA-54 and a control site outside Area G (Site 3) to identify radionuclides that are present within surface and subsurface soils at waste burial sites, to compare the amount of radionuclide uptake by small mammals at waste burial sites to a control site, and to identify the primary mode of contamination to small mammals, either through surface contact or ingestion/inhalation. Three composite samples of at least five animals per sample were collected at each site. Pelts and carcasses of each animal were separated and analyzed independently. Samples were analyzed for {sup 241}Am, {sup 90}Sr, {sup 238}Pu, {sup 239}Pu, total U, and gamma spectroscopy (including {sup 137}Cs). Significantly higher (parametric t-test at p = 0.05) levels of total U, {sup 241}Am, {sup 238}Pu, {sup 239}Pu, and {sup 40}K were detected in pelts as compared to the carcasses of small mammals at TA-54. Concentrations of other measured radionuclides in carcasses were nearly equal to or exceeded the mean concentrations in the pelts. The authors results show higher concentrations in pelts compared to carcasses which is similar to what has been found at waste burial/contaminated sites outside of Los Alamos National Laboratory. Site 1 had significantly higher (alpha = 0.05, F = 0.0095) total U concentrations in carcasses than Sites 2 and 3. Site 2 had significantly higher (alpha = 0.05, F = 0.0195) {sup 239}Pu concentrations in carcasses than either Site 1 or Site 3. A significant difference in {sup 90}Sr concentration existed between Sites 1 and 2 (alpha = 0.05, F = 0.0681) and concentrations of {sup 40}K at Site 1 were significantly different from Site 3.

  15. Small mammal community succession on the beach of Dongting Lake, China after the Three Gorges Project.

    PubMed

    Zhang, Meiwen; Wang, Yong; Li, Bo; Guo, Cong; Huang, Guoxian; Shen, Guo; Zhou, Xunjun

    2014-06-01

    Although the Three Gorges Project (TGP) may have affected the population structure and distribution of plant and animal communities, few studies have analyzed the effect of this project on small mammal communities. Therefore, the present paper compares the small mammal communities inhabiting the beaches of Dongting Lake using field investigations spanning a 20-year period, both before and after the TGP was implemented. Snap traps were used throughout the census. The results indicate that the TGP caused major changes to the structure of the small mammal community at a lake downstream of the dam. First, species abundance on the beaches increased after the project commenced. The striped field mouse (Apodemus agrarius) and the Norway rat (Rattus norvegicus), which rarely inhabited the beach before the TGP, became abundant (with marked population growth) once water was impounded by the Three Gorges Reservoir. Second, dominant species concentration indices exhibited a stepwise decline, indicating that the community structure changed from a single dominant species to a more diverse species mix after TGP implementation. Third, the regulation of water discharge release by the TGP might have caused an increase in the species diversity of the animal community on the beaches. A significant difference in diversity indices was obtained before and after the TGP operation. Similarity indices also indicate a gradual increase in species numbers. Hence, a long-term project should be established to monitor the population fluctuations of the Yangtze vole (Microtus fortis), the striped field mouse and the Norway rat to safeguard against population outbreaks (similar to the Yangtze vole outbreak in 2007), which could cause crop damage to adjacent farmland, in addition to documenting the succession process of the small mammal community inhabiting the beaches of Dongting Lake.

  16. Temporal, spatial and ecological dynamics of speciation among amphi-Beringian small mammals

    USGS Publications Warehouse

    Hope, Andrew G.; Takebayashi, Naoki; Galbreath, Kurt E.; Talbot, Sandra L.; Cook, Joseph A.

    2013-01-01

    Quaternary climate cycles played an important role in promoting diversification across the Northern Hemisphere, although details of the mechanisms driving evolutionary change are still poorly resolved. In a comparative phylogeographical framework, we investigate temporal, spatial and ecological components of evolution within a suite of Holarctic small mammals. We test a hypothesis of simultaneous divergence among multiple taxon pairs, investigating time to coalescence and demographic change for each taxon in response to a combination of climate and geography.

  17. Effects of disturbance on small mammal community structure in the New Jersey Pinelands, USA.

    PubMed

    Shenko, Alicia N; Bien, Walter F; Spotila, James R; Avery, Harold W

    2012-03-01

    We compared small mammal community composition among undisturbed habitats and habitats disturbed by military operations on Warren Grove Gunnery Range (WGR) in the New Jersey Pinelands. WGR is one of the largest tracts of protected land within this globally rare ecosystem. Disturbance in the form of fire, mowing, soil disruption and logging has had a large effect on small mammal occurrence and distribution. Of the 14 small mammal species that occur in the Pinelands, 9 live on WGR, including large populations of the southern bog lemming (Synaptomys cooperi Baird, 1858) and meadow jumping mouse [Zapus hudsonius (Zimmermann, 1780)]. Simpson's Index of Diversity was 0 for most disturbed sites and was generally greater in wetlands than in uplands. White-footed mouse [Peromyscus leucopus (Rafinesque, 1818)] was the most common species on WGR and had a dominant effect on species diversity and community similarity indices. It dominated upland habitats and was the only species to occur in several disturbed habitats, whereas all 9 species occurred in wetlands. Principal components analysis indicated that most variation in species diversity was explained by disturbance and differences between upland and wetland habitats, due to presence of white-footed mice in disturbed and upland sites. Meadow jumping mice, southern bog lemmings and red-back voles [Myodes gapperi (Vigors, 1830)] were positively correlated with wetland habitats, and pine voles [Microtus pinetorum (Le Conte, 1830)], short-tail shrews [Blarina brevicauda (Say, 1823)] and eastern chipmunks [Tamias striatus (Linnaeus, 1758)] were associated with uplands. Habitat heterogeneity at WGR, including extensive undisturbed wetlands and uplands supported a rich diversity of small mammal species.

  18. Small mammals from the Chelemhá Cloud Forest Reserve, Alta Verapaz, Guatemala

    USGS Publications Warehouse

    Matson, Jason O.; Ordóñez-Garza, Nicté; Woodman, Neal; Bulmer, Walter; Eckerlin, Ralph P.; Hanson, J. Delton

    2014-01-01

    We surveyed the small mammals of remnant mixed hardwood-coniferous cloud forest at elevations ranging from 2,100–2,300 m in the Chelemhá Cloud Forest Reserve, Alta Verapaz, Guatemala. Removal-trapping using a combination of live traps, snap traps, and pitfall traps for 6 days in January 2007 resulted in 175 captures of 15 species of marsupials, shrews, and rodents. This diversity of small mammals is the highest that we have recorded from a single locality of the 10 visited during eight field seasons in the highlands of Guatemala. Based on captures, the most abundant species in the community of small mammals is Peromyscus grandis (n = 50), followed by Handleyomys rhabdops (n = 27), Heteromys desmarestianus(n = 18), Reithrodontomys mexicanus (n = 17), Handleyomys saturatior (n = 16), Sorex veraepacis (n = 15), and Scotinomys teguina (n = 13). The remaining eight species were represented by one to five individuals.

  19. Molecular Identification of Echinococcus multilocularis Infection in Small Mammals from Northeast, Iran

    PubMed Central

    Beiromvand, Molouk; Akhlaghi, Lame; Fattahi Massom, Seyed Hossein; Meamar, Ahmad Reza; Darvish, Jamshid; Razmjou, Elham

    2013-01-01

    Background Alveolar echinococcosis is a zoonotic disease caused by the metacestode of Echinococcus multilocularis. Many species of small mammals, including arvicolid rodents or Ochotona spp., are natural intermediate hosts of the cestode. The main aim of this study was to identify natural intermediate hosts of E. multilocularis in Chenaran County, Razavi Khorasan Province, northeastern Iran, where the prevalence of infected wild and domestic carnivores is high. Methodology/Principal Findings A program of trapping was carried out in five villages in which this cestode was reported in carnivores. The livers of 85 small mammals were investigated for the presence of E. multilocularis infection using multiplex PCR of mitochondrial genes. Infections were identified in 30 specimens: 23 Microtus transcaspicus, three Ochotona rufescens, two Mus musculus, one Crocidura gmelini, and one Apodemus witherbyi. Conclusions/Significance A range of small mammals therefore act as natural intermediate hosts for the transmission of E. multilocularis in Chenaran County, and the prevalence suggested that E. multilocularis infection is endemic in this region. The existence of the life cycle of this potentially lethal cestode in the vicinity of human habitats provides a significant risk of human infection. PMID:23875048

  20. Small-mammal herbivore control of secondary succession in New England tidal marshes.

    PubMed

    Gedan, Keryn Bromberg; Crain, Caitlin M; Bertness, Mark D

    2009-02-01

    Secondary succession is impacted by both biotic and abiotic forces, but their relative importance varies due to environmental drivers. Across estuarine salinity gradients, physical stress increases with salinity, and biotic stresses are greater at lower salinities. In southern New England tidal marshes spanning a landscape-scale salinity gradient, we experimentally examined the effects of physical stress and consumer pressure by mammalian herbivores on secondary succession in artificially created bare patches. Recovery was slower in marshes exposed to full-strength seawater, where physical stress is high. Compared to full-strength salt marshes, recovery in low-salinity marshes was much faster and was influenced by small-mammal consumers. At lower salinities, small mammals selectively ate and prevented the establishment of several native and two invasive, nuisance species (Typha angustifolia and Phragmites australis) but were unable to control the expansion of established P. australis stands. By controlling the establishment of competitively dominant species and the trajectory of secondary succession in low-salinity marshes, small mammals may play a cryptic keystone role in estuarine plant communities and are a critical, overlooked consideration in the conservation and management of estuarine marshes.

  1. Interaction of ectoparasites (Mesostigmata, Phthiraptera and Siphonaptera) with small mammals in Cerrado fragments, western Brazil.

    PubMed

    Sponchiado, Jonas; Melo, Geruza L; Landulfo, Gabriel A; Jacinavicius, Fernando C; Barros-Battesti, Darci M; Cáceres, Nilton C

    2015-07-01

    We describe ectoparasite fauna associated with small mammals in fragments of Cerrado biome, central-western Brazil. We analyzed the level of associations and the aggregation patterns according to seasonal and host variations. Small mammals were systematically captured in 54 woodland fragments from February 2012 to July 2013. A total of 1040 animals belonging to eight marsupial and 12 rodent species were sampled; 354 individuals were parasitized by 33 ectoparasite species (twenty five Mesostigmata, seven Phthiraptera and one Siphonaptera). A total of 49 ecological relationships between ectoparasites and small mammals were observed, 24 being new association records. The overall specialization index of all ectoparasites and host species was 0.91 with significant deviation from a random host-parasite association, suggesting a high host-parasite specialization in this system. Specialization indices for ectoparasites ranged from moderate to high, while among host was high, for most species. Contrary to the overall pattern, some ectoparasites had higher prevalence and mean intensity of infestation in the dry season. Overall, ectoparasite prevalence and mean intensity of infestation were not significantly associated with host gender. This study provides significant information about the ectoparasites ecology in relation to specificity, seasonality and hosts gender, contributing to the understanding of host-parasite relationships in Brazilian savannah.

  2. Ecological characteristics of small mammals on a radioactive waste disposal area in southeastern Idaho

    SciTech Connect

    Groves, C.R.; Keller, B.L.

    1983-01-01

    Species composition, diversity, biomass and densities of small mammal populations were examined in crested wheatgrass (Agropyron cristatum) and Russian thistle (Salsola kali) habitats on a solid radioactive waste disposal area and in native sagebrush (Artemisia tridentala) habitat surrounding the disposal area. The 15-month live-trapping study resulted in the marketing of 2384 individuals representing 10 species of small mammals. The deer mouse (Peromyscus maniculatus) was the most common rodent in both disposal area habitats and the adjacent sagebrush habitat; Ord's kangaroo rat (Dipodomys ordii) was also an abundant rodent in all vegetation types. The montane vole (Microtus montanus) was common only in crested wheatgrass stands on the disposal area. Although the adjacent native sagebrush habitat had the highest species diversity and the Russian thistle habitat on the disposal area had the lowest, the total rodent density was not significantly different among the three vegetation types. Crested wheatgrass within the disposal area contained the largest rodent biomass throughout the study, in part due to an increasing M. montanus population. The peak small mammal biomass of 5000 g/ha in creasted wheatgrass and sagebrush habitats was considerably higher than previously reported for similar habitats. Differences in diversity and biomass between the disposal area and surrounding native habitat are most likely related to differences in soil compaction and vegetation between these two areas.

  3. Wild small mammals as sentinels for the environmental transmission of antimicrobial resistance.

    PubMed

    Furness, Lauren E; Campbell, Amy; Zhang, Lihong; Gaze, William H; McDonald, Robbie A

    2017-04-01

    Antimicrobial resistance (AMR) represents a serious threat to human health worldwide. We have tested the use of free-living small mammals (mice, voles and shrews) as sentinels of variation in the distribution of AMR in the environment and the potential for transmission from the natural environment to animal hosts. Escherichia coli isolated from the faeces of small mammals trapped at paired coastal and inland sites were tested for resistance to four antibiotics: trimethoprim, ampicillin, ciprofloxacin and cefotaxime. Coastal individuals were over twice as likely to carry AMR E. coli than inland individuals (79% and 35% respectively), and both between-site and between-species variation was observed. Animals from coastal populations also excreted increased numbers of AMR E. coli and a greater diversity of E. coli phylotypes, including human-associated pathogenic strains. Small mammals appear to be useful bioindicators of fine-scale spatial variation in the distribution of AMR and, potentially, of the risks of AMR transmission to mammalian hosts, including humans.

  4. Scaling the relative dominance of exogenous drivers in structuring desert small mammal assemblages

    NASA Astrophysics Data System (ADS)

    Rodríguez, Daniela; Ojeda, Ricardo A.

    2015-11-01

    Assemblage patterns could be primarily generated by two types of drivers: exogenous (such as environmental and climatic factors) and endogenous (interactions such as competition, predation, mutualism or herbivory). The most widely accepted hypothesis states that at smaller scales (such as patch scale), interspecific interactions are the major drivers structuring communities, whereas at larger regional scales, factors such as climate, topography and soil act as ecological filters that determine assemblage composition. The general aim of this paper is to compare different exogenous drivers in terms of their relative dominance in structuring desert small mammal communities across a range of spatial scales, from patch to regional, and compare them with previous results on endogenous drivers. Our results show that as spatial scale increases, the explanatory power of exogenous factors also increases, e.g. from 17% at the patch scale (i.e. abundance) to 99% at the regional scale (i.e. diversity). Moreover, environmental drivers vary in type and strength depending on the community estimator across several spatial scales. On the other hand, endogenous drivers such as interspecific interactions are more important at the patch scale, diminishing in importance towards the regional scale. Therefore, the relative importance of exogenous versus endogenous drivers affects small mammal assemblage structure at different spatial scales. Our results fill up a knowledge gap concerning ecological drivers of assemblage structure at intermediate spatial scales for Monte desert small mammals, and highlight the importance of dealing with multi-causal factors in explaining ecological patterns of assemblages.

  5. Host specificity and niche partitioning in flea-small mammal networks in Bornean rainforests.

    PubMed

    Wells, K; Lakim, M B; Beaucournu, J-C

    2011-09-01

    The diversity of ectoparasites in Southeast Asia and flea-host associations remain largely understudied. We explore specialization and interaction patterns of fleas infesting non-volant small mammals in Bornean rainforests, using material from a field survey carried out in two montane localities in northwestern Borneo (Sabah, Malaysia) and from a literature database of all available interactions in both lowland and montane forests. A total of 234 flea individuals collected during our field survey resulted in an interaction network of eight flea species on seven live-captured small mammal species. The interaction network from all compiled studies currently includes 15 flea species and 16 small mammal species. Host specificity and niche partitioning of fleas infesting diurnal treeshrews and squirrels were low, with little difference in specialization among taxa, but host specificity in lowland forests was found to be higher than in montane forests. By contrast, Sigmactenus alticola (Siphonaptera: Leptopsyllidae) exhibited low host specificity by infesting various montane and lowland nocturnal rats. However, this species exhibited low niche partitioning as it was the only commonly recorded flea from rats on Borneo. Overall complementary specialization was of intermediate intensity for both networks and differed significantly from random association; this has important implications for specific interactions that are also relevant to the potential spread of vector-borne diseases.

  6. Evidence of antibodies to spotted fever group rickettsiae in small mammals and quail from Mississippi.

    PubMed

    Moraru, Gail Miriam; Goddard, Jerome; Murphy, Alexandria; Link, Diana; Belant, Jerrold L; Varela-Stokes, Andrea

    2013-01-01

    Rickettsia parkeri is a recently recognized human pathogen primarily associated with the Gulf Coast tick Amblyomma maculatum, with immature stages of this tick reported from wild vertebrates. To better understand the role of vertebrates in the natural history of this bacterium, we evaluated small mammals and ground-dwelling birds for evidence of infection with R. parkeri or exposure to the organism. We sampled small mammals (n=39) and passerines (n=47) in both north-central and southeast Mississippi, while northern bobwhite (Colinus virginianus) samples (n=31) were obtained from farms in central Mississippi. Blood from all sampled animals was tested using polymerase chain reaction (PCR) for spotted fever group rickettsiae (SFGR), and for antibodies to SFGR using R. parkeri antigen. Ectoparasite samples were removed from animals and included mites, lice, fleas, and immature ticks. Of 39 small mammal samples collected, 7 were positive for antibodies to SFGR; none tested positive by PCR for DNA of SFGR. Of 47 passerine blood samples collected, none were positive for DNA of SFGR by PCR, nor did any show serological evidence of exposure. Finally, none of 31 northern bobwhite samples tested were positive for SFGR DNA, while 7 were seropositive for rickettsial antibodies. Detection of seropositive rodents and quail suggests a role for these host species in the natural history of SFGR, possibly including R. parkeri, but the extent of their role has not yet been elucidated.

  7. Land use determinants of small mammal abundance and distribution in a plague endemic area of Lushoto District, Tanzania.

    PubMed

    Hieronimo, Proches; Kimaro, Didas N; Kihupi, Nganga I; Gulinck, Hubert; Mulungu, Loth S; Msanya, Balthazar M; Leirs, Herwig; Deckers, Jozef A

    2014-07-01

    Small mammals are considered to be involved in the transmission cycle of bubonic plague, still occurring in different parts of the world, including the Lushoto District in Tanzania. The objective of this study was to determine the relationship between land use types and practices and small mammal abundance and distribution. A field survey was used to collect data in three landscapes differing in plague incidences. Data collection was done both in the wet season (April-June 2012) and dry season (August-October 2012). Analysis of variance and Boosted Regression Trees (BRT) modelling technique were used to establish the relationship between land use and small mammal abundance and distribution. Significant variations (p ≤ 0.05) of small mammal abundance among land use types were identified. Plantation forest with farming, natural forest and fallow had higher populations of small mammals than the other aggregated land use types. The influence of individual land use types on small mammal abundance level showed that, in both dry and wet seasons, miraba and fallow tended to favour small mammals' habitation whereas land tillage practices had the opposite effect. In addition, during the wet season crop types such as potato and maize appeared to positively influence the distribution and abundance of small mammals which was attributed to both shelter and food availability. Based on the findings from this study it is recommended that future efforts to predict and map spatial and temporal human plague infection risk at fine scale should consider the role played by land use and associated human activities on small mammal abundance and distribution.

  8. Long-term effects of precommercial thinning on small mammals in northern Maine

    USGS Publications Warehouse

    Homyack, J.A.; Harrison, D.J.; Krohn, W.B.

    2005-01-01

    Precommercial thinning (PCT) is being practiced increasingly throughout the Acadian forest of eastern North America to meet silvicultural objectives; however, effects of this practice on wildlife, both immediately and several years post-treatment are not well understood. Forest dependent small mammals have ecological roles as prey for numerous avian and mammalian predators, dispersers of seeds, fruit, and spores, and contribute to nutrient cycling. Researchers in the northwestern USA have suggested that thinning of young, regenerating clearcuts may increase the abundance and diversity of some forest-dependent small mammals by increasing rates of forest development and enhancing the ecological representation of mid-successional stands across managed landscapes. We examined the effects of PCT within conifer-dominated forest stands 1-, 6-, 11-, and 16-years post-treatment, on abundances of mice, voles, and shrews, and on within-stand structure in the commercially managed, Acadian forests of northern Maine. We live-trapped small mammals on 24 herbicide-treated clearcuts treated with PCT and on 13 similar, unthinned stands during summers of 2000 and 2001. Thinning of mid-successional conifer stands resulted in increased abundances, (red-backed voles, Clethrionomys gapperi, P = 0.008; masked shrews, Sorex cinereus, P < 0.001) or had no detectable effect on (deer mice, Peromyscus maniculatus, P = 0.544; short-tailed shrews, Blarina brevicauda, P = 0.517) the 4 most common species of Muridae and Soricidae in northern Maine. In general, abundance of deer mice responded more positively to increasing development class and to the number of years since thinning than other species of small mammals. Several within-stand habitat characteristics associated with stand maturity, such as larger stem diameters and a partially open canopy, occurred in thinned stands. Thus, PCT may accelerate the development of habitat attributes typical of mid-successional conifer stands in intensively

  9. Improving ungulate habitat in a region undergoing rapid energy development: Consequences for songbirds and small mammals

    NASA Astrophysics Data System (ADS)

    Bombaci, Sara Petrita

    Habitat manipulation intended to mitigate the impact of energy development on game animals is well underway in the western U.S. Yet, the consequences of these actions for other species are not well understood. A habitat manipulation experiment was established in the Piceance Basin, a region of Colorado undergoing rapid energy development, to evaluate alternative methods (i.e. chaining, hydro-axe, and roller-chop treatments) for reducing pinyon-juniper woodlands to promote mule deer habitat. I use this experimental design to additionally test the initial effects of these treatments on birds and small mammals, and to evaluate selection of habitat components in treatments by birds and small mammals. I found lower bird species occupancy in all treatment plots compared to control plots; however the strength of this response varied by bird guild. I found a positive relationship between bird species occupancy and percent tree cover and a negative relationship between bird species occupancy and percent grass and forb cover. I found no evidence of differences in small mammal species occupancy or density between controls and treatments. I found a positive relationship between small mammal species occupancy and percent grass and forb cover. Species richness did not significantly differ between control and treatment plots for birds or small mammals. My approach and research findings can be used to inform habitat management and multiple-species conservation objectives in pinyon-juniper and sage-steppe ecosystems undergoing energy development. Specifically, I have identified that recently developed roller-chop and hydro-axe treatments have similar impacts to woodland bird guilds as traditional chaining treatments. I have also identified species that are sensitive to habitat mitigation treatments, and thus should be monitored if woodland reduction continues to be used as a habitat mitigation strategy. Since all bird guilds were positively associated with tree cover, woodland

  10. Modelling and spatial discrimination of small mammal assemblages: an example from western Sichuan (China)

    PubMed Central

    Vaniscotte, Amélie; Pleydell, David; Raoul, Francis; Quéré, Jean Pierre; Jiamin, Qiu; Wang, Qian; Tiaoying, Li; Bernard, Nadine; Coeurdassier, Michael; Delattre, Pierre; Takahashi, Kenichi; Weidmann, Jean-Christophe; Giraudoux, Patrick

    2009-01-01

    We investigate the relationship between landscape heterogeneity and the spatial distribution of small mammals in two areas of Western Sichuan, China. Given a large diversity of species trapped within a large number of habitats, we first classified small mammal assemblages and then modelled the habitat of each in the space of quantitative environmental descriptors. Our original two step “classify then model” procedure is appropriate for the frequently encountered study scenario: trapping data collected in remote areas with sampling guided by expert field knowledge. In the classification step, we defined assemblages by grouping sites of similar species composition and relative densities using an expert-class-merging procedure which reduced redundancy in the habitat factor used within a multinomial logistic regression predicting species trapping probabilities. Assemblages were thus defined as mixtures of small mammal frequency distributions in discrete groups of sampled sites. In the modelling step, assemblages’ habitats and environments of the two sampled areas were discriminated in the space of remotely sensed environmental descriptors. First, we compared the discrimination of assemblage/study areas by linear and non-linear forms of Discriminant Analysis (Linear Discriminant Analysis versus Mixture Discriminant Analysis) and of Multiple Regression (Generalized Linear Models versus Multiple Adaptive Regression Splines). The “best” predictive modelling technique was then used to quantify the contribution of each environmental variable in discriminations of assemblages and areas. Mixtures of Gaussians provided a more efficient model of assemblage coverage in environmental space than a single Gaussian cluster model. However, non-linearity in assemblage response to environmental gradients was consistently predicted with lower deviance and misclassification error by Multiple Adaptive Regression Splines. The two study areas were mainly discriminated along

  11. Structure and function of the mammalian middle ear. I: Large middle ears in small desert mammals.

    PubMed

    Mason, Matthew J

    2016-02-01

    Many species of small desert mammals are known to have expanded auditory bullae. The ears of gerbils and heteromyids have been well described, but much less is known about the middle ear anatomy of other desert mammals. In this study, the middle ears of three gerbils (Meriones, Desmodillus and Gerbillurus), two jerboas (Jaculus) and two sengis (elephant-shrews: Macroscelides and Elephantulus) were examined and compared, using micro-computed tomography and light microscopy. Middle ear cavity expansion has occurred in members of all three groups, apparently in association with an essentially 'freely mobile' ossicular morphology and the development of bony tubes for the middle ear arteries. Cavity expansion can occur in different ways, resulting in different subcavity patterns even between different species of gerbils. Having enlarged middle ear cavities aids low-frequency audition, and several adaptive advantages of low-frequency hearing to small desert mammals have been proposed. However, while Macroscelides was found here to have middle ear cavities so large that together they exceed brain volume, the bullae of Elephantulus are considerably smaller. Why middle ear cavities are enlarged in some desert species but not others remains unclear, but it may relate to microhabitat.

  12. Last glacial maximum environments in northwestern Patagonia revealed by fossil small mammals

    NASA Astrophysics Data System (ADS)

    Tammone, Mauro N.; Hajduk, Adan; Arias, Pablo; Teta, Pablo; Lacey, Eileen A.; Pardiñas, Ulyses F. J.

    2014-07-01

    Comparisons of historical and modern assemblages of mammals can yield important insights into patterns and processes of environmental change. Here, we present the first analyses of small mammal assemblages present in northern Patagonia during the last glacial maximum (LGM). Using remains obtained from owl pellets excavated from an archeological cave site (Arroyo Corral I, levels VII-V, carbon dates of 22,400-21,530 cal yr BP), we generate estimates of the minimum number of individuals for all species detected; these estimates, in turn are used to determine relative species abundances. Comparisons of these data with similar analyses of small mammal remains obtained from a second archeological site (ACoII, levels IV-V, carbon dates of 10,010-9220 cal yr BP) as well as from modern owl pellets reveal pronounced changes in relative species abundance since the LGM. In particular, Euneomys chinchilloides and Ctenomys sociabilis - the predominant species during the LGM - declined markedly, suggesting a change from open, bare habitat punctuated by patches of wet meadows and shrubs to the more densely vegetated mosaic of ecotone habitats found in this region today. These data provide important new insights into the environmental changes that have occurred in northern Patagonia over the last 20,000 years.

  13. [Structure of populations and ecological nishes of ectoparasites in the parasite communities of small forest mammals].

    PubMed

    Balashov, Iu S; Bochkov, A V; Vashchenok, V S; Grigor'eva, L A; Staniukovich, M K; Tret'iakov, K A

    2007-01-01

    The paper reports the results of eight-year investigations on the ectoparasites of rodents and insectivores carried out in southern taiga of the Ilmen-Volkhov lowland (Novgorod Region) and Kurgolovsky reserve (Leningrad Region). Twelve species of small mammals were captured including three dominate species--bank vole Clethrionomys glareolus (2722 specimens), common shrew Sorex araneus (1658 specimens), and wood mouse Apodemus uralensis (367 specimens). Parasite community of the bank vole comprises 34 species of mites, ticks, and insects, the community of common shrew comprises 25 species, and the community of A. uralensis includes 28 species. Taxonomic diversity of the ectoparasite communities was shown to be based on the diversity of types of parasitism and ecological nishes of the host body. Permanent ectoparasites are found to be represented by 2 species of lie and 14 species of acariform mites. The group of temporary parasites includes 13 species of fleas, 10 species of gamasid mites. 3 ixodid species and 1 Trombiculidae. There is a common pool of temporary parasites of small mammals in the ecological system of taiga. Significance of different shrew and rodent species as hosts were found to be dependent on the population density in possible hosts and many other factors. Species diversity in the parasite communities of different small mammal species is dependent on the number of possible ecological nishes in the host body. Actual infill of these nishes by ectoparasites is usually lesser than potential one. Species composition of temporary parasites, their occurrence and abundance changes according to season. Interspecific competition in the temporary parasite species can decrease because of the seasonal disjunction of their population peaks. Diversification of the ecological niches of ectoparasites allow simultaneous feeding of more parasite individuals on one host, than in the case of parasitising of single species or several species with similar ecological

  14. Elevational Distribution and Ecology of Small Mammals on Africa’s Highest Mountain

    PubMed Central

    Stanley, William T.; Rogers, Mary Anne; Kihaule, Philip M.; Munissi, Maiko J.

    2014-01-01

    Mt Kilimanjaro is Africa’s highest mountain, and an icon for a country famous for its mammalian fauna. The distribution and abundance of small mammals on the mountain are poorly known. Here we document the distribution of shrews and rodents along an elevational gradient on the southeastern versant of Kilimanjaro. Five sites were sampled with elevational center points of 2000, 2500, 3000, 3500 and 4000 m, using a systematic methodology of standard traps and pitfall lines, to inventory the shrews and rodents of the slope. Sixteen species of mammal were recorded, including 6 shrew and 10 rodent species, and the greatest diversity of both was found at 3000 m, the elevational midpoint of the transect. No species previously unrecorded on Kilimanjaro were observed. Two genera of rodents that occur in nearby mountains (Hylomyscus and Beamys) were not recorded. Myosorex zinki, the only mammal endemic to Mt. Kilimanjaro, which previously was known by only a few specimens collected in the ericaceous or moorland habitat, was found in all but one (the lowest) of the sites sampled, and was one of the most widespread species of small mammal along the gradient. Two shrews (Crocidura allex and Sylvisorex granti) and one rodent (Dendromus insignis) were found throughout the entire transect, with Dendromus being observed at our highest trap point (4240 m). As in similar faunal surveys on other mountains of Tanzania, rainfall influenced the sample success of shrews, but not rodents. Trap success for rodents at 3500 m was notably low. This study contributes further justification for the conservation of the forest habitat of Mt. Kilimanjaro. PMID:25372387

  15. Modeling the effects of fire severity and spatial complexity on Small Mammals in Yosemite National Park, California

    USGS Publications Warehouse

    Roberts, Susan L.; Van Wagtendonk, Jan W.; Miles, A. Keith; Kelt, Douglas A.; Lutz, James A.

    2008-01-01

    We evaluated the impact of fire severity and related spatial and vegetative parameters on small mammal populations in 2 yr- to 15 yr-old burns in Yosemite National Park, California, USA. We also developed habitat models that would predict small mammal responses to fires of differing severity. We hypothesized that fire severity would influence the abundances of small mammals through changes in vegetation composition, structure, and spatial habitat complexity. Deer mouse (Peromyscus maniculatus) abundance responded negatively to fire severity, and brush mouse (P. boylii) abundance increased with increasing oak tree (Quercus spp.) cover. Chipmunk (Neotamias spp.) abundance was best predicted through a combination of a negative response to oak tree cover and a positive response to spatial habitat complexity. California ground squirrel (Spermophilus beecheyi) abundance increased with increasing spatial habitat complexity. Our results suggest that fire severity, with subsequent changes in vegetation structure and habitat spatial complexity, can influence small mammal abundance patterns.

  16. Changes in Trap Temperature as a Method to Determine Timing of Capture of Small Mammals

    PubMed Central

    Orrock, John L.; Connolly, Brian M.

    2016-01-01

    Patterns of animal activity provide important insight into hypotheses in animal behavior, physiological ecology, behavioral ecology, as well as population and community ecology. Understanding patterns of animal activity in field settings is often complicated by the need for expensive equipment and time-intensive methods that limit data collection. Because animals must be active to be detected, the timing of detection (e.g., the timing of capture) may be a useful proxy for estimation of activity time. In this paper, we describe a new method for determining timing of capture for small mammals. In our method, two small temperature loggers are positioned in each trap so that one logger registers the internal temperature of a live-trap at set intervals while the other logger simultaneously records external trap temperature. We illustrate the utility of this technique using field data from live-trapping of deer mice, Peromyscus maniculatus, one of the most ubiquitous, widely distributed small mammals in North America. Traps with animals inside registered consistent increases in internal trap temperature, creating a clear, characteristic temperature deviation between the two data loggers that can determine trap entry time within a very narrow time window (e.g., 10 minutes). We also present pilot data to demonstrate the usefulness of the method for two other small-mammal species. This new method is relatively inexpensive, robust to field conditions, and does not require modification of traps or wiring of new devices. It can be deployed as part of common live-trapping methods, making it possible to assay the timing of capture for a large number of animals in many different ecological contexts. In addition to quantifying timing of capture, this approach may also collect meaningful temperature data and provide insight into the thermal costs of animal activity and relationships between environmental conditions and the time of an animal’s capture. PMID:27792770

  17. Small mammal abundance and habitat relationships on deciduous forested sites with different susceptibility to gypsy moth defoliation

    NASA Astrophysics Data System (ADS)

    Yahner, Richard H.; Smith, Harvey R.

    1991-01-01

    Small mammals are important predators of gypsy moths ( Lymantria dispar L.), which are major defoliators of deciduous forests in the northeastern United States. Abundance and habitat relationships of small mammals were studied during summers 1984 and 1985 on forested sites at Moshannon and Rothrock state forests in two physiographic regions of Pennsylvania (Allegheny High Plateaus Province and Valley and Ridge Province, respectively) that varied in potential susceptibility to defoliation. The white-footed mouse ( Peromyscus leucopus), which is a major vertebrate predator of gypsy moths, was the most common small mammal on all sites. Of the four common species, northern short-tailed shrews ( Blarina brevicauda), southern red-backed voles ( Clethrionomys gapperi), and white-footed mice were more abundant at Moshannon compared to Rothrock State Forest, but masked shrews ( Sorex cinereus) were more abundant at Rothrock. Elevation was a major factor affecting abundance and distribution of small mammals. Because of the greater abundance of small mammals and more suitable physiographic features at Moshannon compared to Rothrock State Forest, small mammals may be more effective as predators on gypsy moths in the Allegheny High Plateaus than the Valley and Ridge Province of Pennsylvania.

  18. The crouching of the shrew: Mechanical consequences of limb posture in small mammals

    PubMed Central

    Kendall, Corinne J.; Hermanson, John W.

    2016-01-01

    An important trend in the early evolution of mammals was the shift from a sprawling stance, whereby the legs are held in a more abducted position, to a parasagittal one, in which the legs extend more downward. After that transition, many mammals shifted from a crouching stance to a more upright one. It is hypothesized that one consequence of these transitions was a decrease in the total mechanical power required for locomotion, because side-to-side accelerations of the body have become smaller, and thus less costly with changes in limb orientation. To test this hypothesis we compared the kinetics of locomotion in two mammals of body size close to those of early mammals (< 40 g), both with parasagittally oriented limbs: a crouching shrew (Blarina brevicauda; 5 animals, 17 trials) and a more upright vole (Microtus pennsylvanicus; 4 animals, 22 trials). As predicted, voles used less mechanical power per unit body mass to perform steady locomotion than shrews did (P = 0.03). However, while lateral forces were indeed smaller in voles (15.6 ± 2.0% body weight) than in shrews (26.4 ± 10.9%; P = 0.046), the power used to move the body from side-to-side was negligible, making up less than 5% of total power in both shrews and voles. The most power consumed for both species was that used to accelerate the body in the direction of travel, and this was much larger for shrews than for voles (P = 0.01). We conclude that side-to-side accelerations are negligible for small mammals–whether crouching or more upright–compared to their sprawling ancestors, and that a more upright posture further decreases the cost of locomotion compared to crouching by helping to maintain the body’s momentum in the direction of travel. PMID:27413633

  19. Comparison of small mammal species diversity near wastewater outfalls, natural streams, and dry canyons

    SciTech Connect

    Raymer, D.F.; Biggs, J.R.

    1994-03-01

    A wide range of plant and wildlife species utilizes water discharged from facilities at Los Alamos National Laboratory (LANL). The purpose of this study was to compare nocturnal small mammal communities at wet areas created by wastewater outfalls with communities in naturally created wet and dry areas. Thirteen locations within LANL boundaries were selected for small mammal mark-recapture trapping. Three of these locations lacked surface water sources and were classified as {open_quotes}dry,{close_quotes} while seven sites were associated with wastewater outfalls ({open_quotes}outfall{close_quotes} sites), and three were located near natural sources of surface water ({open_quotes}natural{close_quotes} sites). Data was collected on site type (dry, outfall or natural), location, species trapped, and the tag number of each individual captured. This data was used to calculate mean number of species, percent capture rate, and species diversity at each type of site. When data from each type of site was pooled, there were no significant differences in these variables between dry, outfall, and natural types. However, when data from individual sites was compared, tests revealed significant differences. All sites in natural areas were significantly higher than dry areas in daily mean number of species, percent capture rate, and species diversity. Most outfall sites were significantly higher than dry areas in all three variables tested. When volume of water from each outfall site was considered, these data indicated that the number of species, percent capture rate, and species diversity of nocturnal small mammals were directly related to the volume of water at a given outfall.

  20. Lassa fever in Guinea: II. Distribution and prevalence of Lassa virus infection in small mammals.

    PubMed

    Demby, A H; Inapogui, A; Kargbo, K; Koninga, J; Kourouma, K; Kanu, J; Coulibaly, M; Wagoner, K D; Ksiazek, T G; Peters, C J; Rollin, P E; Bausch, D G

    2001-01-01

    Rodents of the genus Mastomys form the reservoir for Lassa virus (LV), an arenavirus that causes a potentially severe hemorrhagic illness, Lassa fever (LF). Although Mastomys rodents exist throughout sub-Saharan Africa, areas of human LF appear to be quite focal. The distribution of small mammals and LV-infected Mastomys has been assessed in only a few countries. We conducted a survey of small mammals in selected regions of Guinea to assess the degree to which LV poses a public health risk in that country. A total of 1,616 small mammals, including 956 (59%) Mastomys, were captured from 444 households and seven bush sites. Mastomys made up > 90% of the captured animals in the savannah, savannah-forest transition, and forest regions of Guinea, while Mus musculus dominated in coastal and urban sites. Animals were analyzed via enzyme-linked immunosorbent assay (ELISA) for LV-specific antigen (blood and spleen homogenate) and IgG antibody (blood only). Virus isolation from spleen homogenates was also performed on a subset of animals. Lassa antibody and antigen were found in 96 (11%) and 46 (5%), respectively, of 884 tested Mastomys. Antibody and antigen were essentially mutually exclusive and showed profiles consistent with vertical transmission of both LV and antibody. LV was isolated only from Mastomys. ELISA antigen constituted an acceptable surrogate for virus isolation, with a sensitivity and specificity when performed on blood of 78% (95% confidence interval: 68-83%) and 98% (95-99%), respectively. The proportion of LV-infected Mastomys per region ranged from 0 to 9% and was highest in the savannah and forest zones. The proportion of infected animals per village varied considerably, even between villages in close proximity. Infected animals tended to cluster in relatively few houses, suggesting the existence of focal "hot spots" of LV-infected Mastomys that may account for the observed heterogeneous distribution of LF.

  1. Regulation of forest defoliating insects through small mammal predation: reconsidering the mechanisms.

    PubMed

    Kollberg, Ida; Bylund, Helena; Huitu, Otso; Björkman, Christer

    2014-12-01

    Population densities of forest defoliating insects may be regulated by small mammal predation on the pupae. When outbreaks do occur, they often coincide with warm, dry weather and at barren forest sites. A proposed reason for this is that weather and habitat affect small mammal population density (numerical response) and hence pupal predation. We propose an alternative explanation: weather and habitat affect small mammal feeding behaviour (functional response) and hence the outbreak risks of forest pest insects. We report results from laboratory and field-enclosure experiments estimating rates of pupal predation by bank voles (Myodes glareolus) on an outbreak insect, the European pine sawfly (Neodiprion sertifer), at different temperatures (15 and 20 °C), in different microhabitats (sheltered and non-sheltered), and with or without access to alternative food (sunflower seeds). We found that the probability of a single pupa being eaten at 20 °C was lower than at 15 °C (0.49 and 0.72, respectively). Pupal predation was higher in the sheltered microhabitat than in the open one, and the behaviour of the voles differed between microhabitats. More pupae were eaten in situ in the sheltered microhabitat whereas in the open area more pupae were removed and eaten elsewhere. Access to alternative food did not affect pupal predation. The results suggest that predation rates on pine sawfly pupae by voles are influenced by temperature- and habitat-induced variation in the physiology and behaviour of the predator, and not necessarily solely through effects on predator densities as previously proposed.

  2. Dynamic Edge Effects in Small Mammal Communities across a Conservation-Agricultural Interface in Swaziland

    PubMed Central

    Hurst, Zachary M.; McCleery, Robert A.; Collier, Bret A.; Fletcher, Robert J.; Silvy, Nova J.; Taylor, Peter J.; Monadjem, Ara

    2013-01-01

    Across the planet, high-intensity farming has transformed native vegetation into monocultures, decreasing biodiversity on a landscape scale. Yet landscape-scale changes to biodiversity and community structure often emerge from processes operating at local scales. One common process that can explain changes in biodiversity and community structure is the creation of abrupt habitat edges, which, in turn, generate edge effects. Such effects, while incredibly common, can be highly variable across space and time; however, we currently lack a general analytical framework that can adequately capture such spatio-temporal variability. We extend previous approaches for estimating edge effects to a non-linear mixed modeling framework that captures such spatio-temporal heterogeneity and apply it to understand how agricultural land-uses alter wildlife communities. We trapped small mammals along a conservation-agriculture land-use interface extending 375 m into sugarcane plantations and conservation land-uses at three sites during dry and wet seasons in Swaziland, Africa. Sugarcane plantations had significant reductions in species richness and heterogeneity, and showed an increase in community similarity, suggesting a more homogenized small mammal community. Furthermore, our modeling framework identified strong variation in edge effects on communities across sites and seasons. Using small mammals as an indicator, intensive agricultural practices appear to create high-density communities of generalist species while isolating interior species in less than 225 m. These results illustrate how agricultural land-use can reduce diversity across the landscape and that effects can be masked or magnified, depending on local conditions. Taken together, our results emphasize the need to create or retain natural habitat features in agricultural mosaics. PMID:24040269

  3. Comparison of radionuclide levels in soil, sagebrush, plant litter, cryptogams, and small mammals

    SciTech Connect

    Landeen, D.S.

    1994-09-01

    Soil, sagebrush, plant litter, cryptogam, and small mammal samples were collected and analyzed for cesium-137, strontium-90, plutonium-238, plutonium 239/240, technetium-99, and iodine-129 from 1981 to 1986 at the US Department of Energy Hanford Site in southeastern Washington State as part of site characterization and environmental monitoring activities. Samples were collected on the 200 Areas Plateau, downwind from ongoing waste management activities. Plant litter, cryptogams, and small mammals are media that are not routinely utilized in monitoring or characterization efforts for determination of radionuclide concentrations. Studies at Hanford, other US Department of Energy sites, and in eastern Europe have indicated that plant litter and cryptogams may serve as effective ``natural`` monitors of air quality. Plant litter in this study consists of fallen leaves from sagebrush and ``cryptogams`` describes that portion of the soil crust composed of mosses, lichens, algae, and fungi. Comparisons of cesium-137 and strontium-90 concentrations in the soil, sagebrush, litter, and cryptogams revealed significantly higher (p<0.05) levels in plant litter and cryptogams. Technetium-99 values were the highest in sagebrush and litter. Plutonium-238 and 239/40 and iodine-129 concentrations never exceeded 0.8 pCi/gm in all media. No evidence of any significant amounts of any radionuclides being incorporated into the small mammal community was discovered. The data indicate that plant litter and cryptogams may be better, indicators of environmental quality than soil or vegetation samples. Augmenting a monitoring program with samples of litter and cryptogams may provide a more accurate representation of radionuclide environmental uptake and/or contamination levels in surrounding ecosystems. The results of this study may be applied directly to other radioecological monitoring conducted at other nuclear sites and to the monitoring of other pollutants.

  4. Dynamic edge effects in small mammal communities across a conservation-agricultural interface in Swaziland.

    PubMed

    Hurst, Zachary M; McCleery, Robert A; Collier, Bret A; Fletcher, Robert J; Silvy, Nova J; Taylor, Peter J; Monadjem, Ara

    2013-01-01

    Across the planet, high-intensity farming has transformed native vegetation into monocultures, decreasing biodiversity on a landscape scale. Yet landscape-scale changes to biodiversity and community structure often emerge from processes operating at local scales. One common process that can explain changes in biodiversity and community structure is the creation of abrupt habitat edges, which, in turn, generate edge effects. Such effects, while incredibly common, can be highly variable across space and time; however, we currently lack a general analytical framework that can adequately capture such spatio-temporal variability. We extend previous approaches for estimating edge effects to a non-linear mixed modeling framework that captures such spatio-temporal heterogeneity and apply it to understand how agricultural land-uses alter wildlife communities. We trapped small mammals along a conservation-agriculture land-use interface extending 375 m into sugarcane plantations and conservation land-uses at three sites during dry and wet seasons in Swaziland, Africa. Sugarcane plantations had significant reductions in species richness and heterogeneity, and showed an increase in community similarity, suggesting a more homogenized small mammal community. Furthermore, our modeling framework identified strong variation in edge effects on communities across sites and seasons. Using small mammals as an indicator, intensive agricultural practices appear to create high-density communities of generalist species while isolating interior species in less than 225 m. These results illustrate how agricultural land-use can reduce diversity across the landscape and that effects can be masked or magnified, depending on local conditions. Taken together, our results emphasize the need to create or retain natural habitat features in agricultural mosaics.

  5. Species diversity of ectoparasitic chigger mites (Acari: Prostigmata) on small mammals in Yunnan Province, China.

    PubMed

    Peng, Pei-Ying; Guo, Xian-Guo; Ren, Tian-Guang; Song, Wen-Yu; Dong, Wen-Ge; Fan, Rong

    2016-09-01

    Chigger mites are a large group of arthropods and the larvae of mites are ectoparasites. Some species of ectoparasitic mites (larvae) can be the transmitting vectors of tsutsugamushi disease (scrub typhus). Yunnan Province is located in the southwest of China with complicated topographic landform and high biodiversity, where there are five zoogeographical subregions. Rodents and some other small mammals were trapped and examined for ectoparasitic chigger mites in 29 investigation sites in Yunnan during 2001-2013. From 13,760 individuals and 76 species of small mammal hosts, we collected 274 species of mites, which were identified as comprising 26 genera in two families. The species diversity of chigger mites (274 species) in the present study were not only much higher than that from other provinces of China but also largely exceeded that recorded from other regions and countries in the world. Of the five zoogeographical subregions, both the species diversity and Shannon-Weiner's diversity of mites were the highest in subregion II (southern subregion of Hengduan Mountains) with middle altitudes and middle latitude. Both the species diversity of mites and Shannon-Wiener diversity index showed a parabolic tendency from the low altitude (<500 m) to the high altitude (>3500 m) along the vertical gradients with the peak occurring in the middle-altitude regions (2000-2500 m). Of four dominant hosts, the species richness of mites was highest on Eothenomys miletus (S = 165) and Shannon-Wiener diversity index was highest on Rattus norvegicus (H = 3.13). Along latitude gradients, species richness of chigger mites increased first and then decreased, peaking at 25° to 26° N with 193 mite species. The geographical location, complex topography, and landscape with diverse small mammal hosts in Yunnan Province have contributed to the extremely high species diversity of mites in the province. The large sampling size of small mammal hosts in a wide geographical scope

  6. Reinvasion of small mammals, reptiles, amphibians and insects on a reclaimed coal strip-mine

    SciTech Connect

    Ireland, T.T.; Schemnitz, S.D.; Wolters, G.L.

    1990-12-31

    We conducted wildlife and vegetation sampling on sites reclaimed in 1979, 1982, and 1986, as well as unmined sites, on The Pittsburgh & Midway (P&M) Coal Mining Co.`s McKinley Mine in McKinley County, New Mexico. In June, July, and August 1988 and 1989 we samples small mammals, reptiles, amphibians and insects. Soil and vegetation sampling was conducted in July and September 1988, respectively. We found several significant differences (P < 0.05) among plant and animal data that may have suggested differences between study sites. Recent reclamation procedures conducted or proposed by P&M promise increased wildlife value of reclaimed sites.

  7. Species' traits help predict small mammal responses to habitat homogenization by an invasive grass.

    PubMed

    Ceradini, Joseph P; Chalfoun, Anna D

    2017-03-20

    Invasive plants can negatively affect native species, however, the strength, direction, and shape of responses may vary depending on the type of habitat alteration and the natural history of native species. To prioritize conservation of vulnerable species, it is therefore critical to effectively predict species' responses to invasive plants, which may be facilitated by a framework based on species' traits. We studied the population and community responses of small mammals and changes in habitat heterogeneity across a gradient of cheatgrass (Bromus tectorum) cover, a widespread invasive plant in North America. We live-trapped small mammals over two summers and assessed the effect of cheatgrass on native small mammal abundance, richness, and species-specific and trait-based occupancy, while accounting for detection probability and other key habitat elements. Abundance was only estimated for the most common species, deer mice (Peromyscus maniculatus). All species were pooled for the trait-based occupancy analysis to quantify the ability of small mammal traits (habitat association, mode of locomotion, and diet) to predict responses to cheatgrass invasion. Habitat heterogeneity decreased with cheatgrass cover. Deer mouse abundance increased marginally with cheatgrass. Species richness did not vary with cheatgrass, however, pocket mouse (Perognathus spp.) and harvest mouse (Reithrodontomys spp.) occupancy tended to decrease and increase, respectively, with cheatgrass cover, suggesting a shift in community composition. Cheatgrass had little effect on occupancy for deer mice, 13-lined ground squirrels (Spermophilus tridecemlineatus), and Ord's kangaroo rat (Dipodomys ordii). Species' responses to cheatgrass primarily corresponded with our a priori predictions based on species' traits. The probability of occupancy varied significantly with a species' habitat association but not with diet or mode of locomotion. When considered within the context of a rapid habitat change

  8. Sampling Small Mammals in Southeastern Forests: The Importance of Trapping in Trees

    SciTech Connect

    Loeb, S.C.; Chapman, G.L.; Ridley, T.R.

    1999-01-01

    We investigated the effect of sampling methodology on the richness and abundance of small mammal communities in loblolly pine forests. Trapping in trees using Sherman live traps was included along with routine ground trapping using the same device. Estimates of species richness did not differ among samples in which tree traps were included or excluded. However, diversity indeces (Shannon-Wiener, Simpson, Shannon and Brillouin) were strongly effected. The indeces were significantly greater than if tree samples were included primarily the result of flying squirrel captures. Without tree traps, the results suggested that cotton mince dominated the community. We recommend that tree traps we included in sampling.

  9. Small mammal populations in Maryland meadows during four years of herbicide (Brominal? ) applications

    USGS Publications Warehouse

    Clark, D.R.; Moulton, C.A.; Hines, J.E.; Hoffman, D.J.

    1996-01-01

    The herbicide Brominal? was applied at the recommended rate to one plot in each of three paired 0.6-ha plots; the other three plots were used as controls. Plots were sprayed once in the fall of 1988 and 1989 and twice in the spring of 1990 and 1991. Small mammals were trapped three times during each activity season (April?October) to obtain population estimates before and after spraying and in the spring preceding fall spraying or the fall following spring spraying. Population estimates immediately after spraying gave no evidence of direct mortality. By 1991, dicot vegetation on treated plots was suppressed and mean numbers of meadow voles (Microtus pennsylvanicus) were less than on control plots. Because meadow voles favor dicots over monocots in their diet, reduced availability of dicots may have been related to the smaller vole population estimates. Species diversity of small mammals was negatively correlated with size of vole populations, but was not different between treated and control plots. Brominal apparently induced opaque corneas in nine voles. The condition was found in two voles too small to have been conceived at the time of the last previous spray nearly 8 months earlier, suggesting exposure to residue alone.

  10. Hardwood energy crops and wildlife diversity: Investigating potential benefits for breeding birds and small mammals

    SciTech Connect

    Schiller, A.; Tolbert, V.R.

    1996-08-01

    Hardwood energy crops have the potential to provide a profit to growers as well as environmental benefits (for water quality, soil stabilization, chemical runoff, and wildlife habitat). Environmental considerations are important for both sustainable development of bioenergy technologies on agricultural lands, and for public support. The Environmental Task of the US DOE`s Biofuels feedstock Development Program (BFDP) is working with industry, universities and others to determine how to plant, manage and harvest these crops to maximize environmental advantages and minimize impacts while economically meeting production needs. One research objective is to define and improve wildlife habitat value of these energy crops by exploring how breeding birds and small mammals use them. The authors have found increased diversity of birds in tree plantings compared to row crops. However, fewer bird and small mammal species use the tree plantings than use natural forest. Bird species composition on hardwood crops studied to date is a mixture of openland and forest bird species. Restricted research site availability to date has limited research to small acreage sites of several years of age, or to a few larger acreage but young (1--2 year) plantings. Through industry collaboration, research began this season on bird use of diverse hardwood plantings (different ages, acreages, tree species) in the southeast. Together with results of previous studies, this research will help define practical energy crop guidelines to integrate native wildlife benefits with productive energy crops.

  11. Near-complete extinction of native small mammal fauna 25 years after forest fragmentation.

    PubMed

    Gibson, Luke; Lynam, Antony J; Bradshaw, Corey J A; He, Fangliang; Bickford, David P; Woodruff, David S; Bumrungsri, Sara; Laurance, William F

    2013-09-27

    Tropical forests continue to be felled and fragmented around the world. A key question is how rapidly species disappear from forest fragments and how quickly humans must restore forest connectivity to minimize extinctions. We surveyed small mammals on forest islands in Chiew Larn Reservoir in Thailand 5 to 7 and 25 to 26 years after isolation and observed the near-total loss of native small mammals within 5 years from <10-hectare (ha) fragments and within 25 years from 10- to 56-ha fragments. Based on our results, we developed an island biogeographic model and estimated mean extinction half-life (50% of resident species disappearing) to be 13.9 years. These catastrophic extinctions were probably partly driven by an invasive rat species; such biotic invasions are becoming increasingly common in human-modified landscapes. Our results are thus particularly relevant to other fragmented forest landscapes and suggest that small fragments are potentially even more vulnerable to biodiversity loss than previously thought.

  12. Effects of Large and Small-Source Seismic Surveys on Marine Mammals and Sea Turtles

    NASA Astrophysics Data System (ADS)

    Holst, M.; Richardson, W. J.; Koski, W. R.; Smultea, M. A.; Haley, B.; Fitzgerald, M. W.; Rawson, M.

    2006-05-01

    L-DEO implements a marine mammal and sea turtle monitoring and mitigation program during its seismic surveys. The program consists of visual observations, mitigation, and/or passive acoustic monitoring (PAM). Mitigation includes ramp ups, powerdowns, and shutdowns of the seismic source if marine mammals or turtles are detected in or about to enter designated safety radii. Visual observations for marine mammals and turtles have taken place during all 11 L-DEO surveys since 2003, and PAM was done during five of those. Large sources were used during six cruises (10 to 20 airguns; 3050 to 8760 in3; PAM during four cruises). For two interpretable large-source surveys, densities of marine mammals were lower during seismic than non- seismic periods. During a shallow-water survey off Yucatán, delphinid densities during non-seismic periods were 19x higher than during seismic; however, this number is based on only 3 sightings during seismic and 11 sightings during non-seismic. During a Caribbean survey, densities were 1.4x higher during non-seismic. The mean closest point of approach (CPA) for delphinids for both cruises was significantly farther during seismic (1043 m) than during non-seismic (151 m) periods (Mann-Whitney U test, P < 0.001). Large whales were only seen during the Caribbean survey; mean CPA during seismic was 1722 m compared to 1539 m during non-seismic, but sample sizes were small. Acoustic detection rates with and without seismic were variable for three large-source surveys with PAM, with rates during seismic ranging from 1/3 to 6x those without seismic (n = 0 for fourth survey). The mean CPA for turtles was closer during non-seismic (139 m) than seismic (228 m) periods (P < 0.01). Small-source surveys used up to 6 airguns or 3 GI guns (75 to 1350 in3). During a Northwest Atlantic survey, delphinid densities during seismic and non-seismic were similar. However, in the Eastern Tropical Pacific, delphinid densities during non-seismic were 2x those during

  13. Ectoparasites (sucking lice, fleas and ticks) of small mammals in southeastern Kenya

    PubMed Central

    OGUGE, N. O.; DURDEN, L. A.; KEIRANS, J. E.; BALAMI, H. D.; SCHWAN, T. G.

    2013-01-01

    During 1998–2000, at least 14 species (n = 309) of small mammals were live-trapped and examined for ectoparasites in moist forests of the Taita and Shimba Hills and drier savannah habitats of Nguruman, southeastern Kenya. Ectoparasites were recorded from 11 species of mammals. Five species of sucking lice [Hoplopleura inexpectans Johnson, H. intermedia Kellogg & Ferris, Polyplax reclinata (Nitzsch), P. waterstoni Bedford and Schizophthirus graphiuri Ferris], six species of fleas (Ctenophthalmus leptodactylous Hubbard, Dinopsyllus grypurus Jordan & Rothschild, D. lypusus Jordan & Rothschild, Hypsophthalmus campestris Jordan & Rothschild, Listropsylla basilewskyi Smit and Xiphiopsylla lippa Jordan) and at least six species of ticks (Amblyomma sp., Haemaphysalis sp., Ixodes sp., I. alluaudi Neumann, I. cumulatimpunctatus Schulze, I. muniensis Arthur & Burrow and Rhipicephalus sp.) were recorded from these hosts. Four of the five species of sucking lice were host specific whereas P. reclinata was recorded from two different species of white-toothed shrews, Crocidura spp. Although fleas and ticks were less host specific, C. leptodactylous, D. grypurus and I. cumulatimpunctatus were only recorded from the murid rodent Praomys delectorum (Thomas), Amblyomma sp. was only recorded from the nesomyid rodent Beamys hindei Thomas, Rhipicephalus sp. was only recorded from the murid Lemniscomys striatus (L.) and I. muniensis was only recorded from the dormouse Graphiurus microtis (Noack). More species of ectoparasites and significantly greater infestation prevalences were recorded from small mammals in moist habitats compared with those from the savannah habitat. At least one of the fleas recorded, D. lypusus, is a known vector of Yersinia pestis Lehmann & Neumann, the causative agent of plague, which is present in the region. PMID:19941604

  14. Ribosomal and mitochondrial DNA analysis of Trichuridae nematodes of carnivores and small mammals.

    PubMed

    Guardone, Lisa; Deplazes, Peter; Macchioni, Fabio; Magi, Marta; Mathis, Alexander

    2013-10-18

    Several species of Trichuridae nematodes can infect dogs, cats and wild mammals. The diagnosis of these infections relies on the microscopic identification of eggs which are characterized by a similar "lemon" shape and polar plugs in all Trichuridae. Thus, morphological diagnosis to species level is challenging. The use of biomolecular diagnostic methods is desirable but very little genetic data are known from Trichuridae of carnivores and small mammals. The aim of this work was to genetically characterize several species of Trichuridae that can affect dogs, cats and wild mammals, as a basis to develop molecular diagnostic tests. Specimens (adult worms or eggs) of Eucoleus aerophilus (syn. Capillaria aerophila), Eucoleus boehmi (syn. Capillaria boehmi), Pearsonema plica (syn. Capillaria plica), Aonchotheca putorii (syn. Capillaria putorii), Calodium hepaticum (syn. Capillaria hepatica), Calodium splenaecum (syn. Capillaria splenaeca) and Trichuris vulpis were obtained from carcasses of red foxes, feces of dogs, the liver of a vole and from the spleen of Crocidura sp. Parts of the small subunit rRNA (18S rRNA) gene and of the mitochondrial cytochrome c oxidase subunit I (cox 1 mtDNA) gene were amplified from the above mentioned nematodes, yielding the first 18S rRNA gene sequences of all the capillariid nematodes and the first cox 1 mtDNA sequences of E. boehmi, P. plica, C. hepaticum, A. putorii and T. vulpis. The 18S rRNA gene is highly conserved among the different species and not suitable as a target for specific diagnostic oligonucleotides. However, these sequences contribute to a better understanding of the complex taxonomic relations among Trichuridae. Indeed, a dendrogram based on the 18S rRNA gene locus supports the latest taxonomic revision. Interspecies divergence was much higher at the cox 1 mtDNA gene locus, rendering it suitable for DNA barcoding and particularly valuable in resolving closely related species. Furthermore, the mitochondrial genetic

  15. Small mammal community composition in cornfields, roadside ditches, and prairies in eastern Nebraska

    USGS Publications Warehouse

    Kirsch, E.M.

    1997-01-01

    Community composition of small mammals was examined in prairies, cornfields, and their adjacent roadside ditches in eastern Nebraska. Western harvest mice (Reithrodontomys megalotis) and meadow voles (Microtus pennsylvanicus) were associated with prairie habitat, were common in ditches, but avoided cornfields. Prairie voles (M. Ochrogaster) and white-footed mice (Peromyscus leucopus) were associated with ditch habitat, were common in prairies, but avoided cornfields. Short-tailed shrews (Blarina brevicauda) avoided cornfields, were associated with ditches next to cornfields, but were common in prairies and ditches next to prairies. Deer mice (P. Maniculatus) were associated with cornfields but were relatively common in prairies and ditches. House mice (Mus musculus) were most common in ditches next to cornfields, occurred in cornfields and ditches next to prairies, but were not captured in prairies. Although community composition appears to differ among prairies, ditches, and cornfields, ditches support a more complete suite of the native small mammal species in large and relatively even numbers, whereas cornfields only support deer mice in large numbers.

  16. Small mammals: paratenic hosts for species of Toxocara in eastern Slovakia.

    PubMed

    Antolová, D; Reiterová, K; Stanko, M; Zalesny, G; Fričová, J; Dvorožňáková, E

    2013-03-01

    Toxocara spp., an aetiological agent of a serious helminthozoonosis, is a common roundworm of domestic and wild carnivores worldwide. The study aimed to estimate the seroprevalence of Toxocara in small mammals from different localities in eastern Slovakia. Anti-Toxocara antibodies were detected in 6.4% out of 2140 examined animals trapped in eastern Slovakia. Due to their high density and observed high seroprevalence of toxocariasis, Apodemus agrarius, A. flavicollis, Myodes glareolus and Mus spicilegus (10.9, 4.2, 3.6 and 11.2%, respectively) represent important sources of the infection. A significant correlation between type of food and Toxocara positivity was detected: granivores (7.2%) and invertebratophages (7.1%) were positive more frequently than herbivores (2.1%). In the years monitored, cyclic changes of seroprevalence were observed. A higher prevalence of antibodies in the spring was followed by a decrease in summer. In autumn, seroprevalence started to rise and stayed at a similar level through the winter. Seroprevalence of the examined animals confirms their contact with Toxocara spp. and demonstrates the presence of the aetiological agent in the monitored locality. Areas with a high prevalence of infected animals present constant infectious pressure on definitive hosts, thus also increasing infection risk for humans and paratenic hosts. The study confirmed the contact of small mammals with Toxocara spp. and demonstrated the presence and circulation of an aetiological agent in the localities monitored in eastern Slovakia.

  17. Host-Parasite Associations in Small Mammal Communities in Semiarid Savanna Ecosystems of East Africa.

    PubMed

    Guerra, Ana Sofia; Eckerlin, Ralph P; Dowling, Ashley P G; Durden, Lance A; Robbins, Richard G; Dittmar, Katharina; Helgen, Kristofer M; Agwanda, Bernard; Allan, Brian F; Hedlund, Tyler; Young, Hillary S

    2016-07-01

    Despite the established importance of rodents as reservoirs of vector-borne zoonoses in East Africa, there is relatively limited information regarding the infestation parameters and host associations of ectoparasites that vector many such pathogens among small mammals in this region. Between 2009 and 2013, small mammals were live-trapped in the semiarid savanna of Kenya. A subset of these individual hosts, including 20 distinct host taxa, was examined for ectoparasites, which were identified to species. Species of fleas, ticks, mites, and sucking lice were recorded. Based on these data, we calculated host-specific infestation parameters, documented host preferences among ectoparasites, conducted a rarefaction analysis and extrapolation to determine if ectoparasites were adequately sampled, and assessed nestedness for fleas to understand how pathogens might spread in this system. We found that the flea community structure was significantly nested. Understanding the ectoparasite network structure may have significant human relevance, as at least seven of the ectoparasite species collected are known vectors of pathogens of medical importance in the region, including Yersinia pestis, Rickettsia spp., and Theileria parva, the causative agents of plague, spotted fevers and other rickettsial illnesses in humans, and theileriosis, respectively.

  18. Disentangle the Causes of the Road Barrier Effect in Small Mammals through Genetic Patterns.

    PubMed

    Ascensão, Fernando; Mata, Cristina; Malo, Juan E; Ruiz-Capillas, Pablo; Silva, Catarina; Silva, André P; Santos-Reis, Margarida; Fernandes, Carlos

    2016-01-01

    Road barrier effect is among the foremost negative impacts of roads on wildlife. Knowledge of the factors responsible for the road barrier effect is crucial to understand and predict species' responses to roads, and to improve mitigation measures in the context of management and conservation. We built a set of hypothesis aiming to infer the most probable cause of road barrier effect (traffic effect or road surface avoidance), while controlling for the potentially confounding effects road width, traffic volume and road age. The wood mouse Apodemus sylvaticus was used as a model species of small and forest-dwelling mammals, which are more likely to be affected by gaps in cover such as those resulting from road construction. We confront genetic patterns from opposite and same roadsides from samples of three highways and used computer simulations to infer migration rates between opposite roadsides. Genetic patterns from 302 samples (ca. 100 per highway) suggest that the highway barrier effect for wood mouse is due to road surface avoidance. However, from the simulations we estimated a migration rate of about 5% between opposite roadsides, indicating that some limited gene flow across highways does occur. To reduce highway impact on population genetic diversity and structure, possible mitigation measures could include retrofitting of culverts and underpasses to increase their attractiveness and facilitate their use by wood mice and other species, and setting aside roadside strips without vegetation removal to facilitate establishment and dispersal of small mammals.

  19. The influence of small mammal burrowing activity on water storage at the Hanford Site

    SciTech Connect

    Landeen, D.S.

    1994-09-01

    The amount and rate at which water may penetrate a protective barrier and come into contact with buried radioactive waste is a major concern. Because burrowing animals eventually will reside on the surface of any protective barrier, the effect these burrow systems may have on the loss or retention of water needs to be determined. The first section of this document summarizes the known literature relative to small mammals and the effects that burrowing activities have on water distribution, infiltration, and the overall impact of burrows on the ecosystem. Topics that are summarized include burrow air pressures, airflow, burrow humidity, microtopography, mounding, infiltration, climate, soil evaporation, and discussions of large pores relative to water distribution. The second section of this document provides the results of the study that was conducted at the Hanford Site to determine what effect small mammal burrows have on water storage. This Biointrusion task is identified in the Permanent Isolation Surface Barrier Development Plan in support of protective barriers. This particular animal intrusion task is one part of the overall animal intrusion task identified in Animal Intrusion Test Plan.

  20. Epizootiological survey of small mammals as Leptospira spp. reservoirs in Eastern Croatia.

    PubMed

    Stritof Majetic, Zrinka; Galloway, Renee; Ruzic Sabljic, Eva; Milas, Zoran; Mojcec Perko, Vesna; Habus, Josipa; Margaletic, Josip; Pernar, Renata; Turk, Nenad

    2014-03-01

    In this survey we investigated a population of small mammals in Eastern Croatia in order to determine Leptospira carriage rates and identify circulating serovars. Out of 67 trapped animals, 20 (29.9%) isolates were obtained. Identification of isolates using microscopic agglutination test, pulsed field gel electrophoresis and multi locus sequence typing revealed that 10 (50.0%) isolates belong to serogroup Pomona, serovar Mozdok, 6 (30.0%) isolates to serogroup Australis, serovar Jalna, 2 (10.0%) isolates to serogroup Sejroe, serovar Saxkoebing, and 1 (5.0%) isolate to serogroup Grippotyphosa, serovar Grippotyphosa. One isolate from serogroup Bataviae was unable to be identified to the serovar level. Amplification of a 331-bp region of the locus LA0322 using real-time polymerase chain reaction determined that 12 (60.0%) isolates belong to L. kirschneri, 6 (30.0%) isolates to L. interrogans, and 2 (10.0%) isolates to L. borgpetersenii. Leptospira carriage rate was high (29.9%), which corresponds to a high incidence of human and domestic animal leptospirosis in Eastern Croatia. Furthermore, 90.0% of the isolates belong to serogroups Pomona, Australis and Sejroe which are also the most prevalent serogroups in humans in this area. These findings suggest that small mammals might be an important source of Leptospira spp. infection in Eastern Croatia.

  1. Disentangle the Causes of the Road Barrier Effect in Small Mammals through Genetic Patterns

    PubMed Central

    Ascensão, Fernando; Mata, Cristina; Malo, Juan E.; Ruiz-Capillas, Pablo; Silva, Catarina; Silva, André P.; Santos-Reis, Margarida; Fernandes, Carlos

    2016-01-01

    Road barrier effect is among the foremost negative impacts of roads on wildlife. Knowledge of the factors responsible for the road barrier effect is crucial to understand and predict species’ responses to roads, and to improve mitigation measures in the context of management and conservation. We built a set of hypothesis aiming to infer the most probable cause of road barrier effect (traffic effect or road surface avoidance), while controlling for the potentially confounding effects road width, traffic volume and road age. The wood mouse Apodemus sylvaticus was used as a model species of small and forest-dwelling mammals, which are more likely to be affected by gaps in cover such as those resulting from road construction. We confront genetic patterns from opposite and same roadsides from samples of three highways and used computer simulations to infer migration rates between opposite roadsides. Genetic patterns from 302 samples (ca. 100 per highway) suggest that the highway barrier effect for wood mouse is due to road surface avoidance. However, from the simulations we estimated a migration rate of about 5% between opposite roadsides, indicating that some limited gene flow across highways does occur. To reduce highway impact on population genetic diversity and structure, possible mitigation measures could include retrofitting of culverts and underpasses to increase their attractiveness and facilitate their use by wood mice and other species, and setting aside roadside strips without vegetation removal to facilitate establishment and dispersal of small mammals. PMID:26978779

  2. Drivers of Intensity and Prevalence of Flea Parasitism on Small Mammals in East African Savanna Ecosystems.

    PubMed

    Young, Hillary S; Dirzo, Rodolfo; McCauley, Douglas J; Agwanda, Bernard; Cattaneo, Lia; Dittmar, Katharina; Eckerlin, Ralph P; Fleischer, Robert C; Helgen, Lauren E; Hintz, Ashley; Montinieri, John; Zhao, Serena; Helgen, Kristofer M

    2015-06-01

    The relative importance of environmental factors and host factors in explaining variation in prevalence and intensity of flea parasitism in small mammal communities is poorly established. We examined these relationships in an East African savanna landscape, considering multiple host levels: across individuals within a local population, across populations within species, and across species within a landscape. We sampled fleas from 2,672 small mammals of 27 species. This included a total of 8,283 fleas, with 5 genera and 12 species identified. Across individual hosts within a site, both rodent body mass and season affected total intensity of flea infestation, although the explanatory power of these factors was generally modest (<10%). Across host populations in the landscape, we found consistently positive effects of host density and negative effects of vegetation cover on the intensity of flea infestation. Other factors explored (host diversity, annual rainfall, anthropogenic disturbance, and soil properties) tended to have lower and less consistent explanatory power. Across host species in the landscape, we found that host body mass was strongly positively correlated with both prevalence and intensity of flea parasitism, while average robustness of a host species to disturbance was not correlated with flea parasitism. Cumulatively, these results provide insight into the intricate roles of both host and environmental factors in explaining complex patterns of flea parasitism across landscape mosaics.

  3. Comparison of small mammal prevalence of Leishmania (Leishmania) mexicana in five foci of cutaneous leishmaniasis in the State of Campeche, Mexico.

    PubMed

    Van Wynsberghe, N R; Canto-Lara, S B; Sosa-Bibiano, E I; Rivero-Cárdenas, N A; Andrade-Narváez, F J

    2009-01-01

    In the Yucatan Peninsula of Mexico, 95% of the human cases of Cutaneous Leishmaniasis are caused by Leishmania (Leishmania) mexicana with an incidence rate of 5.08 per 100,000 inhabitants. Transmission is limited to the winter months (November to March). One study on wild rodents has incriminated Ototylomys phyllotis and Peromyscus yucatanicus as primary reservoirs of L. (L.) mexicana in the focus of La Libertad, Campeche. In the present study, the prevalence of both infection and disease caused by L. (L.) mexicana in small terrestrial mammals were documented during five transmission seasons (1994-2004) in five foci of Leishmaniasis in the state of Campeche. Foci separated by only 100 km, with similar relative abundances of small mammals, were found to differ significantly in their prevalence of both symptoms and infection. Transmission rates and reservoir species seemed to change in space as well as in time which limited the implementation of effective control measures of the disease even in a small endemic area such as the south of the Yucatan Peninsula.

  4. Failure to prove arenavirus infection among the small mammals from an endemic area of Korean hemorrhagic nephrosonephritis.

    PubMed

    Okuno, T; Casals, J; Kim, K H; Walton, D W; Shin, H K

    1976-08-01

    In the light of recent knowledge on a complex of diseases caused by a new group of viruses, arenaviruses, virological studies largely directed toward small field mammals were undertaken during 1973-1974 aiming at etiological clarification of Korean hemorrhagic nephrosonephritis (KHNN). Specimens were collected in an endemic area of KHNN located north to northeast of Seoul. Virus isolation tests with 299 urine specimens and 131 mite pools recovered from small mammals and 14 acute stage sera from typical cases yielded negative results. Complement-fixation (CF) tests failed to detect antibodies against the antigens of Congo, lymphocytic choriomeningitis (LCM), Tacaribe, and Pichinde viruses among 366 small mammal sera. In addition, CF tests of 59 of the above sera against Apoi and Lassa virus antigens were negative. The results do not support the likelihood of an arenavirus being transmitted among Korean small field mammals, the overwhelming majority of which were Apodemus agrarius. A hypothesis that KHNN is caused by a virus of small field mammal origin was not proved within the technical limit of relatively unsophisticated methods employed herein.

  5. Identification of a new Borrelia species among small mammals in areas of northern Spain where Lyme disease is endemic.

    PubMed

    Gil, Horacio; Barral, Marta; Escudero, Raquel; García-Pérez, Ana L; Anda, Pedro

    2005-03-01

    The role of small mammals as reservoir hosts for Borrelia burgdorferi was investigated in several areas where Lyme disease is endemic in northern Spain. A low rate of infestation by Ixodes ricinus nymphs was found in the small mammal populations studied that correlated with the near-absence of B. burgdorferi sensu lato in 184 animals tested and with the lack of transmission of B. burgdorferi sensu lato to I. ricinus larvae that fed on them. In contrast, questing ticks collected at the same time and in the same areas were found to carry a highly variable B. burgdorferi sensu lato repertoire (B. burgdorferi sensu stricto, Borrelia garinii, Borrelia valaisiana, and Borrelia afzelii). Interestingly, the only isolate obtained from small mammals (R57, isolated from a bank vole) grouped by phylogenetic analyses with other Borrelia species but in a separate clade from the Lyme disease and relapsing fever organisms, suggesting that it is a new species. This new agent was widely distributed among small mammals, with infection rates of 8.5 to 12% by PCR. Moreover, a high seroprevalence to B. burgdorferi sensu lato was found in the animal sera, suggesting cross-reactivity between B. burgdorferi sensu lato and R57. Although small mammals do not seem to play an important role as reservoirs for B. burgdorferi sensu lato in the study area, they seem to be implicated in the maintenance of spirochetes similar to R57.

  6. Identification of a New Borrelia Species among Small Mammals in Areas of Northern Spain Where Lyme Disease Is Endemic

    PubMed Central

    Gil, Horacio; Barral, Marta; Escudero, Raquel; García-Pérez, Ana L.; Anda, Pedro

    2005-01-01

    The role of small mammals as reservoir hosts for Borrelia burgdorferi was investigated in several areas where Lyme disease is endemic in northern Spain. A low rate of infestation by Ixodes ricinus nymphs was found in the small mammal populations studied that correlated with the near-absence of B. burgdorferi sensu lato in 184 animals tested and with the lack of transmission of B. burgdorferi sensu lato to I. ricinus larvae that fed on them. In contrast, questing ticks collected at the same time and in the same areas were found to carry a highly variable B. burgdorferi sensu lato repertoire (B. burgdorferi sensu stricto, Borrelia garinii, Borrelia valaisiana, and Borrelia afzelii). Interestingly, the only isolate obtained from small mammals (R57, isolated from a bank vole) grouped by phylogenetic analyses with other Borrelia species but in a separate clade from the Lyme disease and relapsing fever organisms, suggesting that it is a new species. This new agent was widely distributed among small mammals, with infection rates of 8.5 to 12% by PCR. Moreover, a high seroprevalence to B. burgdorferi sensu lato was found in the animal sera, suggesting cross-reactivity between B. burgdorferi sensu lato and R57. Although small mammals do not seem to play an important role as reservoirs for B. burgdorferi sensu lato in the study area, they seem to be implicated in the maintenance of spirochetes similar to R57. PMID:15746336

  7. Novel Babesia and Hepatozoon agents infecting non-volant small mammals in the Brazilian Pantanal, with the first record of the tick Ornithodoros guaporensis in Brazil.

    PubMed

    Wolf, Rafael William; Aragona, Mônica; Muñoz-Leal, Sebastián; Pinto, Leticia Borges; Melo, Andréia Lima Tomé; Braga, Isis Assis; Costa, Jackeliny dos Santos; Martins, Thiago Fernandes; Marcili, Arlei; Pacheco, Richard de Campos; Labruna, Marcelo B; Aguiar, Daniel Moura

    2016-04-01

    Taking into account the diversity of small terrestrial mammals of the Pantanal, the present study aimed to verify the occurrence of infection by Ehrlichia spp., Anaplasma spp., Rickettsia spp., Hepatozoon spp., Babesia spp. and parasitism by ticks in non-volant small mammals collected in the Brazilian Pantanal. Samples of blood, liver and spleen were collected from 64 captured animals, 22 marsupials and 42 rodents. Pathogen detection was performed by the use of genus-specific Polymerase Chain Reaction (PCR) assays. Ticks collected from the animals consisted of Amblyomma sculptum and Amblyomma triste nymphs, and Ornithodoros guaporensis larvae. None of the vertebrate samples (blood, liver, or spleen) yielded detectable DNA of Rickettsia spp. or Ehrlichia spp. The blood of the rodent Hylaeamys megacephalus yielded an Anaplasma sp. genotype (partial 16S rRNA gene) 99% similar to multiple Anaplasma spp. genotypes around the world. The blood of three rodents of the species Calomys callosus were positive for a novel Hepatozoon sp. agent, phylogenetically related (18S rDNA gene) to distinct Hepatozoon genotypes that have been detected in rodents from different parts of the world. One marsupial (Monodelphis domestica) and three rodents (Thrichomys pachyurus) were positive to novel piroplasmid genotypes, phylogenetically (18S rDNA gene) related to Theileria bicornis, Cytauxzoon manul, and Cytauxzoon felis. The present study provides the first molecular detection of Hepatozoon sp. and piroplasmids in small mammals in Brazil. Additionally, we expanded the distribution of O. guaporensis to Brazil, since this tick species was previously known to occur only in Bolivia.

  8. Prevalence and Phylogenetic Analysis of Orientia tsutsugamushi in Small Mammals in Hanoi, Vietnam.

    PubMed

    Hotta, Kozue; Pham, Hang T T; Hoang, Huong T; Trang, Tu C; Vu, Thuy N; Ung, Trang T H; Shimizu, Kenta; Arikawa, Jiro; Yamada, Akio; Nguyen, Hoa T; Nguyen, Hang L K; Le, Mai T Q; Hayasaka, Daisuke

    2016-02-01

    Rodents are important reservoirs of many human pathogens transmitted via arthropod vectors. Arthropod-borne bacteria belonging to the family Rickettsiaceae cause acute febrile diseases in humans worldwide, but the real burdens of rickettsial diseases appear to be underestimated in Hanoi, Vietnam, because differential diagnosis on the basis of clinical signs and symptoms is confounded by the presence of other tropical infectious diseases with similar signs and symptoms. To know the prevalence of bacteria of the family Rickettsiaceae among small mammals in Hanoi, 519 animals thriving in the public places were captured and examined for the presence of bacterial sequences using duplex PCR. Nucleotide sequences specific for Orientia tsutsugamushi were detected in seven samples (1.3%). Out of seven animals, two were captured in a market, whereas five were in hospitals. None of the captured small mammals tested positive for the genus Rickettsia. The nucleotide sequence analysis of the genes encoding the 47-kDa high-temperature requirement A (47-kDa HtrA) and 56-kDa type-specific antigen (TSA) showed that these seven isolates were indistinguishable from each other. O. tsutsugamushi isolated in this study was closely related phylogenetically to the Gilliam strain, which was originally isolated at the border of Assam and Burma, rather than to those isolated in the central to southern part of Vietnam. It should be emphasized that Vietnamese hospitals were heavily infested by small rodents and some of them harbored O. tsutsugamushi. Strict hygienic control should be implemented to mitigate the potential risk posed by O. tsutsugamushi in hospital settings.

  9. DNA Microarray Platform for Detection and Surveillance of Viruses Transmitted by Small Mammals and Arthropods

    PubMed Central

    Khan, Mohd Jaseem; Trabuco, Amanda Cristina; Alfonso, Helda Liz; Figueiredo, Mario Luis; Batista, Weber Cheli; Badra, Soraya Jabur; Figueiredo, Luiz Tadeu; Lavrador, Marco Aurélio

    2016-01-01

    Viruses transmitted by small mammals and arthropods serve as global threats to humans. Most emergent and re-emergent viral agents are transmitted by these groups; therefore, the development of high-throughput screening methods for the detection and surveillance of such viruses is of great interest. In this study, we describe a DNA microarray platform that can be used for screening all viruses transmitted by small mammals and arthropods (SMAvirusChip) with nucleotide sequences that have been deposited in the GenBank. SMAvirusChip was designed with more than 15,000 oligonucleotide probes (60-mers), including viral and control probes. Two SMAvirusChip versions were designed: SMAvirusChip v1 contains 4209 viral probes for the detection of 409 viruses, while SMAvirusChip v2 contains 4943 probes for the detection of 416 viruses. SMAvirusChip was evaluated with 20 laboratory reference-strain viruses. These viruses could be specifically detected when alone in a sample or when artificially mixed within a single sample. The sensitivity of SMAvirusChip was evaluated using 10-fold serial dilutions of dengue virus (DENV). The results showed a detection limit as low as 2.6E3 RNA copies/mL. Additionally, the sensitivity was one log10 lower (2.6E2 RNA copies/mL) than quantitative real-time RT-PCR and sufficient to detect viral genomes in clinical samples. The detection of DENV in serum samples of DENV-infected patients (n = 6) and in a whole blood sample spiked with DENV confirmed the applicability of SMAvirusChip for the detection of viruses in clinical samples. In addition, in a pool of mosquito samples spiked with DENV, the virus was also detectable. SMAvirusChip was able to specifically detect viruses in cell cultures, serum samples, total blood samples and a pool of mosquitoes, confirming that cellular RNA/DNA did not interfere with the assay. Therefore, SMAvirusChip may represent an innovative surveillance method for the rapid identification of viruses transmitted by small

  10. Effect of inbreeding on juvenile mortality in some small mammal species.

    PubMed

    Ralls, K; Ballou, J

    1982-04-01

    In breeding records for 12 species of small mammals from 9 families in 3 orders, individuals with an inbreeding coefficient of 0 were classified as non-inbred, those with inbreeding coefficients greater than 0 as inbred. Juvenile mortality was defined as all deaths prior to 1/2 of the age of sexual maturity for each species. It was significantly higher for inbred than for noninbred animals in 11 of the 12 species using a 1-tailed sign test, and by Fisher's exact test in 3 species. Monodelphis domestica, Wiedomys pyrrhorhinos and and Dolichotis salinicola. The higher mortality of inbred young of the species with the largest sample size, Elephantulus rufescens, was irrespective of litter size and of the parity of the dam.

  11. Small mammals from the early Pleistocene of the Granada Basin, southern Spain

    NASA Astrophysics Data System (ADS)

    García-Alix, Antonio; Minwer-Barakat, Raef; Suárez, Elvira Martín; Freudenthal, Matthijs

    2009-09-01

    The Pliocene and Pleistocene continental sedimentary records of the western sector of the Granada Basin, southern Spain, consist of alternating fluvial and lacustrine/palustrine sediments. Two Quaternary sections from this sector have been sampled: Huétor Tájar and Tojaire. They have yielded remains of rodents, insectivores and lagomorphs. The presence in the Huétor Tájar and Tojaire sections of Mimomys, Apodemus atavus, Castillomys rivas and two different species of Allophaiomys, indicates an Early Pleistocene age. These deposits, which are related to a fluvio-lacustrine system, can be differentiated from an older (Pliocene) braided fluvial system. Their dating has important repercussions on the paleogeographic reconstruction of the basin. The conditions inferred from the ecological preferences of the small mammal associations are wet and cold. These associations suggest a predominance of open herbaceous habitats, followed by forested habitats; semiaquatic habitats are the least represented.

  12. Does small mammal prey guild affect the exposure of predators to anticoagulant rodenticides?

    PubMed

    Tosh, D G; McDonald, R A; Bearhop, S; Lllewellyn, N R; Fee, S; Sharp, E A; Barnett, E A; Shore, R F

    2011-10-01

    Ireland has a restricted small mammal prey guild but still includes species most likely to consume anticoagulant rodenticide (AR) baits. This may enhance secondary exposure of predators to ARs. We compared liver AR residues in foxes (Vulpes vulpes) in Northern Ireland (NI) with those in foxes from Great Britain which has a more diverse prey guild but similar agricultural use of ARs. Liver ARs were detected in 84% of NI foxes, more than in a comparable sample of foxes from Scotland and similar to that of suspected AR poisoned animals from England and Wales. High exposure in NI foxes is probably due to greater predation of commensal rodents and non-target species most likely to take AR baits, and may also partly reflect greater exposure to highly persistent brodifacoum and flocoumafen. High exposure is likely to enhance risk and Ireland may be a sentinel for potential effects on predator populations.

  13. Fleas of Small Mammals on Reunion Island: Diversity, Distribution and Epidemiological Consequences

    PubMed Central

    Guernier, Vanina; Lagadec, Erwan; LeMinter, Gildas; Licciardi, Séverine; Balleydier, Elsa; Pagès, Frédéric; Laudisoit, Anne; Dellagi, Koussay; Tortosa, Pablo

    2014-01-01

    The diversity and geographical distribution of fleas parasitizing small mammals have been poorly investigated on Indian Ocean islands with the exception of Madagascar where endemic plague has stimulated extensive research on these arthropod vectors. In the context of an emerging flea-borne murine typhus outbreak that occurred recently in Reunion Island, we explored fleas' diversity, distribution and host specificity on Reunion Island. Small mammal hosts belonging to five introduced species were trapped from November 2012 to November 2013 along two altitudinal transects, one on the windward eastern and one on the leeward western sides of the island. A total of 960 animals were trapped, and 286 fleas were morphologically and molecularly identified. Four species were reported: (i) two cosmopolitan Xenopsylla species which appeared by far as the prominent species, X. cheopis and X. brasiliensis; (ii) fewer fleas belonging to Echidnophaga gallinacea and Leptopsylla segnis. Rattus rattus was found to be the most abundant host species in our sample, and also the most parasitized host, predominantly by X. cheopis. A marked decrease in flea abundance was observed during the cool-dry season, which indicates seasonal fluctuation in infestation. Importantly, our data reveal that flea abundance was strongly biased on the island, with 81% of all collected fleas coming from the western dry side and no Xenopsylla flea collected on almost four hundred rodents trapped along the windward humid eastern side. The possible consequences of this sharp spatio-temporal pattern are discussed in terms of flea-borne disease risks in Reunion Island, particularly with regard to plague and the currently emerging murine typhus outbreak. PMID:25188026

  14. Phylogenetic and morphological relationships between nonvolant small mammals reveal assembly processes at different spatial scales.

    PubMed

    Luza, André Luís; Gonçalves, Gislene Lopes; Hartz, Sandra Maria

    2015-02-01

    The relative roles of historical processes, environmental filtering, and ecological interactions in the organization of species assemblages vary depending on the spatial scale. We evaluated the phylogenetic and morphological relationships between species and individuals (i.e., inter- and intraspecific variability) of Neotropical nonvolant small mammals coexisting in grassland-forest ecotones, in landscapes and in regions, that is, three different scales. We used a phylogenetic tree to infer evolutionary relationships, and morphological traits as indicators of performance and niche similarities between species and individuals. Subsequently, we applied phylogenetic and morphologic indexes of diversity and distance between species to evaluate small mammal assemblage structures on the three scales. The results indicated a repulsion pattern near forest edges, showing that phylogenetically similar species coexisted less often than expected by chance. The strategies for niche differentiation might explain the phylogenetic repulsion observed at the edge. Phylogenetic and morphological clustering in the grassland and at the forest interior indicated the coexistence of closely related and ecologically similar species and individuals. Coexistence patterns were similar whether species-trait values or individual values were used. At the landscape and regional scales, assemblages showed a predominant pattern of phylogenetic and morphological clustering. Environmental filters influenced the coexistence patterns at three scales, showing the importance of phylogenetically conserved ecological tolerances in enabling taxa co-occurrence. Evidence of phylogenetic repulsion in one region indicated that other processes beyond environmental filtering are important for community assembly at broad scales. Finally, ecological interactions and environmental filtering seemed important at the local scale, while environmental filtering and historical colonization seemed important for community

  15. Small mammal-heavy metal concentrations from mined and control sites

    USGS Publications Warehouse

    Smith, G.J.; Rongstad, O.J.

    1982-01-01

    Total body concentrations of zinc, copper, cadmium, lead, nickel, mercury and arsenic were determined for Peromyscus maniculatus and Microtus pennsylvanicus from an active zinc-copper mine near Timmins, Ontario, Canada, and a proposed zinc-copper mine near Crandon, Wisconsin, USA. Metal concentrations were evaluated with respect to area, species, sex and age groups. Metal concentrations in Peromyscus from the proposed mine site were not different from those collected in a third area where no mine or deposit exists. This is probably due to the 30 m of glacial material over the proposed mine site deposit. A statistical interaction between area, species, sex and age was observed for zinc and copper concentrations in small mammals we examined. Peromyscus from the mine site had consistently higher metal concentrations than Peromyscus from the control site. Greater total body cadmium and lead concentrations in adult?compared with juvenile?Peromyscus collected at the mine site suggests age-dependent accumulation of these toxic metals. Microtus did not exhibit this age-related response, and responded to other environmental metals more erratically and to a lesser degree. Differences in the response of these two species to environmental metal exposure may be due to differences in food habits. Nickel, mercury and arsenic concentrations in small mammals from the mine site were not different from controls. Heavy metal concentrations are also presented for Sorex cinereus, Blarina brevicauda and Zapus hudsonicus without respect to age and sex cohorts. Peromyscus may be a potentially important species for the monitoring of heavy metal pollution.

  16. Small mammals as indicators of short-term and long-term disturbance in mixed prairie

    USGS Publications Warehouse

    Leis, S.A.; Leslie, David M.; Engle, David M.; Fehmi, J.S.

    2008-01-01

    Disturbance by military maneuvers over short and long time scales may have differential effects on grassland communities. We assessed small mammals as indicators of disturbance by military maneuvers in a mixed prairie in southern Oklahoma USA. We examined sites on two soil series, Foard and Lawton, across a gradient of disturbance intensity. A MANOVA showed that abundance of small mammals was associated (p = 0.03) with short-term (cover of vehicle tracks) disturbance but was not associated (p = 0.12) with long-term (loss of soil organic carbon, SOC) disturbance intensity. At the individual species level, Sigmodon hispidus (cotton rat) and Peromyscus maniculatus (deer mouse) occurred across all levels of disturbance and in both soil types. Only P. maniculatus abundance changed (p < 0.01) with short-term disturbance and increased by about one individual per 5% of additional track-cover. Abundance of P. maniculatus also increased (p = 0.04) by about three individuals per 1% increase in soil carbon. Chaetodipus hispidus (hispid pocket mouse) and Reithrodontomys fulvescens (fulvous harvest mouse) only occurred in single soil types limiting their potential as more general indicators. Abundance of P. maniculatus was positively related to shifts in plant species composition and likely reflected changes in vegetation structure (i.e. litter depth) and forage availability resulting from disturbance. Peromyscus maniculatus may be a useful biological indicator of ecosystem change because it responded predictably to both long-term and short-term disturbance and, when coupled with soil, plant, and disturbance history variables, can reveal land condition trends. ?? Springer Science+Business Media B.V. 2007.

  17. Rickettsia spp. in wild small mammals in Lower Bavaria, South-Eastern Germany.

    PubMed

    Schex, Susanne; Dobler, Gerhard; Riehm, Julia; Müller, Jörg; Essbauer, Sandra

    2011-05-01

    So far, data on the natural cycle of rickettsiae of the tick-borne spotted fever group (SFG) in Central Europe are barely available. Some studies showed the occurrence of different Rickettsia species in their arthropod vectors, but it is unclear which animals might have any kind of reservoir function. This survey was therefore set up to provide information on the occurrence of SFG rickettsiae in small mammals in Germany. A total of 124 rodents and insectivores were collected over a period of 3 years in Lower Bavaria, South-Eastern Germany. Screening for Rickettsia antibodies was performed using immunofluorescence with Rickettsia conorii and R. helvetica slides, and the comparability of sera and body fluids (transudates) was investigated in these assays. Further, real-time polymerase chain reaction (PCR) was used for screening of Rickettsial DNA in rodents and insectivores. Ear versus liver tissue was compared to evaluate the more suitable tissue for detection of specific DNA. Further, a new PCR targeting the 18S ribosomal nucleic acid was established as internal control. The results indicated that transudates are a sufficient alternative to proof infection in cases where no sera are available. Rickettsial DNA, that is, Rickettsia felis and R. helvetica, was found in seven animals with the ears proving to be a proper choice for PCR. Statistical analyses revealed that the presence of ectoparasites and the body size positively correlated with the occurrence of rickettsial DNA. Overall, our study suggests that rodents and other small mammals may act as reservoir hosts for Rickettsia. However, with the course of infection and its transmission in wild animals still unknown, further investigations are needed to better understand the natural cycle of SFG rickettsiae.

  18. Spatial variation in keystone effects: Small mammal diversity associated with black-tailed prairie dog colonies

    USGS Publications Warehouse

    Cully, J.F.; Collinge, S.K.; Van Nimwegen, R. E.; Ray, C.; Johnson, W.C.; Thiagarajan, B.; Conlin, D.B.; Holmes, B.E.

    2010-01-01

    Species with extensive geographic ranges may interact with different species assemblages at distant locations, with the result that the nature of the interactions may vary spatially. Black-tailed prairie dogs Cynomys ludovicianus occur from Canada to Mexico in grasslands of the western Great Plains of North America. Black-tailed prairie dogs alter vegetation and dig extensive burrow systems that alter grassland habitats for plants and other animal species. These alterations of habitat justify the descriptor " ecological engineer," and the resulting changes in species composition have earned them status as a keystone species. We examined the impact of black-tailed prairie dogs on small mammal assemblages by trapping at on- and off-colony locations at eight study areas across the species' geographic range. We posed 2 nested hypotheses: 1) prairie dogs function as a keystone species for other rodent species; and 2) the keystone role varies spatially. Assuming that it does, we asked what are the sources of the variation? Black-tailed prairie dogs consistently functioned as a keystone species in that there were strong statistically significant differences in community composition on versus off prairie dog colonies across the species range in prairie grassland. Small mammal species composition varied along both latitudinal and longitudinal gradients, and species richness varied from 4 to 11. Assemblages closer together were more similar; such correlations approximately doubled when including only on- or off-colony grids. Black-tailed prairie dogs had a significant effect on associated rodent assemblages that varied regionally, dependent upon the composition of the local rodent species pool. Over the range of the black-tailed prairie dog, on-colony rodent richness and evenness were less variable, and species composition was more consistent than off-colony assemblages. ?? 2010 The Authors.

  19. Heterogeneous road networks have no apparent effect on the genetic structure of small mammal populations.

    PubMed

    Grilo, Clara; Del Cerro, Irene; Centeno-Cuadros, Alejandro; Ramiro, Victor; Román, Jacinto; Molina-Vacas, Guillem; Fernández-Aguilar, Xavier; Rodríguez, Juan; Porto-Peter, Flávia; Fonseca, Carlos; Revilla, Eloy; Godoy, José A

    2016-09-15

    Roads are widely recognized to represent a barrier to individual movements and, conversely, verges can act as potential corridors for the dispersal of many small mammals. Both barrier and corridor effects should generate a clear spatial pattern in genetic structure. Nevertheless, the effect of roads on the genetic structure of small mammal populations still remains unclear. In this study, we examine the barrier effect that different road types (4-lane highway, 2-lane roads and single-lane unpaved roads) may have on the population genetic structure of three species differing in relevant life history traits: southern water vole Arvicola sapidus, the Mediterranean pine vole Microtus duodecimcostatus and the Algerian mouse Mus spretus. We also examine the corridor effect of highway verges on the Mediterranean pine vole and the Algerian mouse. We analysed the population structure through pairwise estimates of FST among subpopulations bisected by roads, identified genetic clusters through Bayesian assignment approaches, and used simple and partial Mantel tests to evaluate the relative barrier or corridor effect of roads. No strong evidences were found for an effect of roads on population structure of these three species. The barrier effect of roads seems to be site-specific and no corridor effect of verges was found for the pine vole and Algerian mouse populations. The lack of consistent results among species and for each road type lead us to believe that the ability of individual dispersers to use those crossing structures or the habitat quality in the highway verges may have a relatively higher influence on gene flow among populations than the presence of crossing structures per se. Further research should include microhabitat analysis and the estimates of species abundance to understand the mechanisms that underlie the genetic structure observed at some sites.

  20. Phylogenetic and morphological relationships between nonvolant small mammals reveal assembly processes at different spatial scales

    PubMed Central

    Luza, André Luís; Gonçalves, Gislene Lopes; Hartz, Sandra Maria

    2015-01-01

    The relative roles of historical processes, environmental filtering, and ecological interactions in the organization of species assemblages vary depending on the spatial scale. We evaluated the phylogenetic and morphological relationships between species and individuals (i.e., inter- and intraspecific variability) of Neotropical nonvolant small mammals coexisting in grassland-forest ecotones, in landscapes and in regions, that is, three different scales. We used a phylogenetic tree to infer evolutionary relationships, and morphological traits as indicators of performance and niche similarities between species and individuals. Subsequently, we applied phylogenetic and morphologic indexes of diversity and distance between species to evaluate small mammal assemblage structures on the three scales. The results indicated a repulsion pattern near forest edges, showing that phylogenetically similar species coexisted less often than expected by chance. The strategies for niche differentiation might explain the phylogenetic repulsion observed at the edge. Phylogenetic and morphological clustering in the grassland and at the forest interior indicated the coexistence of closely related and ecologically similar species and individuals. Coexistence patterns were similar whether species-trait values or individual values were used. At the landscape and regional scales, assemblages showed a predominant pattern of phylogenetic and morphological clustering. Environmental filters influenced the coexistence patterns at three scales, showing the importance of phylogenetically conserved ecological tolerances in enabling taxa co-occurrence. Evidence of phylogenetic repulsion in one region indicated that other processes beyond environmental filtering are important for community assembly at broad scales. Finally, ecological interactions and environmental filtering seemed important at the local scale, while environmental filtering and historical colonization seemed important for community

  1. Fleas of small mammals on Reunion Island: diversity, distribution and epidemiological consequences.

    PubMed

    Guernier, Vanina; Lagadec, Erwan; LeMinter, Gildas; Licciardi, Séverine; Balleydier, Elsa; Pagès, Frédéric; Laudisoit, Anne; Dellagi, Koussay; Tortosa, Pablo

    2014-09-01

    The diversity and geographical distribution of fleas parasitizing small mammals have been poorly investigated on Indian Ocean islands with the exception of Madagascar where endemic plague has stimulated extensive research on these arthropod vectors. In the context of an emerging flea-borne murine typhus outbreak that occurred recently in Reunion Island, we explored fleas' diversity, distribution and host specificity on Reunion Island. Small mammal hosts belonging to five introduced species were trapped from November 2012 to November 2013 along two altitudinal transects, one on the windward eastern and one on the leeward western sides of the island. A total of 960 animals were trapped, and 286 fleas were morphologically and molecularly identified. Four species were reported: (i) two cosmopolitan Xenopsylla species which appeared by far as the prominent species, X. cheopis and X. brasiliensis; (ii) fewer fleas belonging to Echidnophaga gallinacea and Leptopsylla segnis. Rattus rattus was found to be the most abundant host species in our sample, and also the most parasitized host, predominantly by X. cheopis. A marked decrease in flea abundance was observed during the cool-dry season, which indicates seasonal fluctuation in infestation. Importantly, our data reveal that flea abundance was strongly biased on the island, with 81% of all collected fleas coming from the western dry side and no Xenopsylla flea collected on almost four hundred rodents trapped along the windward humid eastern side. The possible consequences of this sharp spatio-temporal pattern are discussed in terms of flea-borne disease risks in Reunion Island, particularly with regard to plague and the currently emerging murine typhus outbreak.

  2. Effects of aerial applications of esfenvalerate on small mammals and birds in Douglas-fir seed orchards

    USGS Publications Warehouse

    Blus, L.J.; Henny, C.J.; Rice, C.P.; Grove, R.A.

    1992-01-01

    Although no adverse effects were documented, this study did not provide data sufficient to adequately test for effects of aerial spraying of esfenvalerate on small mammal populations or nesting of birds in Douglas-fir seed orchards. Small mammal trapping data were too sparse to provide statistical testing with reasonable power. Residues of the R and S forms of fenvalerate were low with maxima of 0.56 and 1.72 ?g/g, respectively in pelage of a deer mouse. No diagnostic residue data are available to interpret our results.

  3. Host substitution by Ixodes persulcatus (Acari: Ixodidae) larvae in the years of deep depression in the abundance of small mammals.

    PubMed

    Uspensky, I; Rubina, M

    1992-01-01

    A phenomenon of host substitution by the taiga tick (Ixodes persulcatus) larvae was observed by the authors in the western part of the Soviet Far East. In the mountain forests where the highest abundance of I. persulcatus was found, larvae usually fed on small mammals (primarily on Clethrionomys rufocanus, C. rutilus and Apodemus speciosus). Numerous larvae were found, however, on the mountain hare (Lepus timidus) in the years of deep depression in the abundance of small mammals. The host substitution is considered as one of the mechanisms stabilizing the abundance of I. persulcatus adults.

  4. Lessons from the swamp: developing small molecules that confer salamander muscle cellularization in mammals.

    PubMed

    Um, JungIn; Jung, Da-Woon; Williams, Darren Reece

    2017-12-01

    The ability of salamanders, such as newts, to regenerate damaged tissues has been studied for centuries. A prominent example of this regenerative power is the ability to re-grow entire amputated limbs. One important step in this regeneration process is skeletal muscle cellularization, in which the muscle fibers break down into dedifferentiated, mononuclear cells that proliferate and form new muscle in the replacement limb. In contrast, mammalian skeletal muscle does not undergo cellularization after injury. A significant proportion of research about tissue regeneration in salamanders aims to characterize regulatory genes that may have mammalian homologs. A less mainstream approach is to develop small molecule compounds that induce regeneration-related mechanisms in mammals. In this commentary, we discuss progress in discovering small molecules that induce cellularization in mammalian muscle. New research findings using these compounds has also shed light on cellular processes that regulate cellularization, such as apoptotic signaling. Although formidable technical hurdles remain, this progress increases our understanding of tissue regeneration and provide opportunities for developing small molecules that may enhance tissue repair in humans.

  5. Small mammals associated with colonies of black-tailed prairie dogs (Cynomys ludovicianus) in the Southern High Plains

    USGS Publications Warehouse

    Pruett, A.L.; Boal, C.W.; Wallace, M.C.; Whitlaw, H.A.; Ray, J.D.

    2010-01-01

    We compared diversity and abundance of small mammals at colonies of black-tailed prairie dogs (Cynomys ludovicianus) and paired non-colony sites. Of colonies of black-tailed prairie dogs in our study area, >80 were on slopes of playa lakes; thus, we used sites of colonies and non-colonies that were on slopes of playa lakes. We trapped small mammals on 29 pairs of sites. Overall abundance did not differ between types of sites, but some taxa exhibited associations with colonies (Onychomys leucogaster) or non-colonies (Chaetodipus hispidus, Reithrodontomys, Sigmodon hispidus). Diversity and evenness of small mammals did not differ between colonies and non-colonies in 2002, but were higher on non-colonies in 2003. Although we may not have detected some rare or infrequently occurring species, our data reveal differences in diversity and evenness of more common species among the types of sites. Prairie dogs are touted as a keystone species with their colonies associated with a greater faunal diversity than adjacent lands. Our findings contradict several studies reporting greater diversity and abundance of small mammals at colonies of prairie dogs. We suggest that additional research across a wider landscape and incorporating landscape variables beyond the immediate trapping plot may further elucidate interspecific associations between black-tailed prairie dogs and species of small rodents.

  6. Antibodies to rabies virus in terrestrial wild mammals in native rainforest on the north coast of São Paulo State, Brazil.

    PubMed

    Araujo, Danielle B; Martorelli, Luzia A; Kataoka, Ana Paula G A; Campos, Angélica C A; Rodrigues, Camila S; Sanfilippo, Luiz F; Cunha, Elenice S; Durigon, Edison L; Favoretto, Silvana R

    2014-07-01

    Rabies causes thousands of human and animal deaths worldwide each year. The emergent importance of rabies in wild animals demonstrates the necessity of epidemiologic studies of infection in these species toward the development of better strategies for prevention and control of rabies. We analyzed the circulation of rabies virus among wildlife species from a native rainforest in São Paulo State, Brazil. We used the rapid fluorescent focus inhibition test (RFFIT) to test for rabies virus-neutralizing antibodies in 139 captured terrestrial mammals and the fluorescent antibody test (FAT), mouse inoculation test (MIT), and reverse-transcriptase (RT)-PCR to test for virus in samples from the central nervous system of 53 animals found dead. The percentage of samples positive by RFFIT was 10.8%. All samples tested by FAT, MIT, and RT-PCR were negative. Research should be continued to obtain a better understanding of the role of wildlife in the circulation and transmission of rabies virus.

  7. Status and challenges for conservation of small mammal assemblages in South America.

    PubMed

    Kelt, Douglas A; Meserve, Peter L

    2014-08-01

    South America spans about 44° latitude, covers almost 18 million km(2) , and is second only to Africa in continental mammal species richness. In spite of this richness, research on the status of this fauna and on the nature and magnitude of contemporary threats remains limited. Distilling threats to this diverse fauna at a continental scale is challenging, in part because of the limited availability of rigorous studies. Recognizing this constraint, we summarize key threats to small mammals in South America, emphasizing the roles of habitat loss and degradation, direct persecution, and the increasing threat of climate change. We focus on three regional 'case studies': the tropical Andes, Amazonia and adjacent lowland regions, and the southern temperate region. We close with a brief summary of recent findings at our long-term research site in north-central Chile as they pertain to projected threats to this fauna. Habitat alteration is a pervasive threat that has been magnified by market forces and globalization (e.g. extensive agricultural development in Amazonia), and threatens increasing numbers of populations and species. Climate change poses even greater threats, from changes in rainfall and runoff regimes and resulting changes in vegetative structure and composition to secondary influences on fire dynamics. It is likely that many changes have yet to be recognized, but existing threats suggest that the future may bring dramatic changes in the distribution of many mammal taxa, although it is not clear if key habitat elements (vegetation) will respond as rapidly as climatic factors, leading to substantial uncertainty. Climate change is likely to result in 'winners' and 'losers' but available information precludes detailed assessment of which species are likely to fall into which category. In the absence of long-term monitoring and applied research to characterize these threats more accurately, and to develop strategies to reduce their impacts, managers already are

  8. Type X Toxoplasma gondii in a wild mussel and terrestrial carnivores from coastal California: new linkages between terrestrial mammals, runoff and toxoplasmosis of sea otters.

    PubMed

    Miller, M A; Miller, W A; Conrad, P A; James, E R; Melli, A C; Leutenegger, C M; Dabritz, H A; Packham, A E; Paradies, D; Harris, M; Ames, J; Jessup, D A; Worcester, K; Grigg, M E

    2008-09-01

    Sea otters in California are commonly infected with Toxoplasma gondii. A unique Type X strain is responsible for 72% of otter infections, but its prevalence in terrestrial animals and marine invertebrates inhabiting the same area was unknown. Between 2000 and 2005, 45 terrestrial carnivores (lions, bobcats, domestic cats and foxes) and 1396 invertebrates (mussels, clams and worms) were screened for T. gondii using PCR and DNA sequencing to determine the phylogeographic distribution of T. gondii archetypal I, II, III and Type X genotypes. Marine bivalves have been shown to concentrate T. gondii oocysts in the laboratory, but a comprehensive survey of wild invertebrates has not been reported. A California mussel from an estuary draining into Monterey Bay was confirmed positive for Type X T. gondii by multilocus PCR and DNA sequencing at the B1 and SAG1 loci. This mussel was collected from nearshore marine waters just after the first significant rainfall event in the fall of 2002. Of 45 carnivores tested at the B1, SAG1, and GRA6 typing loci, 15 had PCR-confirmed T. gondii infection; 11 possessed alleles consistent with infection by archetypal Type I, II or III strains and 4 possessed alleles consistent with Type X T. gondii infection. No non-canonical alleles were identified. The four T. gondii strains with Type X alleles were identified from two mountain lions, a bobcat and a fox residing in coastal watersheds adjacent to sea otter habitat near Monterey Bay and Estero Bay. Confirmation of Type X T. gondii in coastal-dwelling felids, canids, a marine bivalve and nearshore-dwelling sea otters supports the hypotheses that feline faecal contamination is flowing from land to sea through surface runoff, and that otters can be infected with T. gondii via consumption of filter-feeding marine invertebrates.

  9. Are tropical small mammals physiologically vulnerable to Arrhenius effects and climate change?

    PubMed

    Lovegrove, Barry G; Canale, Cindy; Levesque, Danielle; Fluch, Gerhard; Reháková-Petrů, Milada; Ruf, Thomas

    2014-01-01

    There is some urgency in the necessity to incorporate physiological data into mechanistic, trait-based, demographic climate change models. Physiological responses at the individual level provide the mechanistic link between environmental changes and individual performances and hence population dynamics. Here we consider the causal relationship between ambient temperature (Ta) and metabolic rate (MR), namely, the Arrhenius effect, which is directly affected by global warming through increases in average global air temperatures and the increase in the frequency and intensity of extreme climate events. We measured and collated data for several small, free-ranging tropical arboreal mammals and evaluated their vulnerability to Arrhenius effects and putative heat stress associated with climate change. Skin temperatures (Tskin) were obtained from free-ranging tarsiers (Tarsius syrichta) on Bohol Island, Philippines. Core body temperature (Tb) was obtained from the greater hedgehog tenrec (Setifer setosus) and the gray brown mouse lemur (Microcebus ravelobensis) from Ankarafantsika, Madagascar. Tskin for another mouse lemur, Microcebus griseorufus, was obtained from the literature. All four species showed evidence of hyperthermia during the daytime rest phase in the form of either Tskin or Tb that was higher than the normothermic Tb during the nighttime active phase. Potentially, tropical arboreal mammals with the lowest MRs and Tb, such as tarsiers, are the most vulnerable to sustained heat stress because their Tb is already close to Ta. Climate change may involve increases in MRs due to Arrhenius effects, especially during the rest phase or during torpor and hibernation. The most likely outcome of increased Arrhenius effects with climate change will be an increase in energy expenditure at the expense of other critical functions such as reproduction or growth and will thus affect fitness. However, we propose that these hypothetical Arrhenius costs can be, and in some

  10. The influence of small-mammal burrowing activity on water storage at the Hanford Site

    SciTech Connect

    Landeen, D.S.

    1994-12-31

    This paper summarizes the activities that were conducted in support of the long-term surface barrier development program by Westinghouse Hanford Company to determine the degree that small-mammal burrow systems affect the loss or retention of water in the soils at the Hanford Site in Washington state. An animal intrusion lysimeter facility was constructed, consisting of two outer boxes buried at grade, which served as receptacles for six animal intrusion lysimeters. Small burrowing animals common the Hanford Site were introduced over a 3- to 4-month period. Supplemental precipitation was added monthly to three of the lysimeters with a rainfall simulator (rainulator). Information collected from the five tests indicated that (1) during summer months, water was lost in all the lysimeters, including the supplemental precipitation added with the rainulator; and (2) during winter months, all lysimeters gained water. The data indicate little difference in the amount of water stored between control and animal lysimeters. The overall water loss was attributed to surface evaporation, a process that occurred equally in control and treatment lysimeters. Other causes of water loss are a result of (1) constant soil turnover and subsequent drying, and (2) burrow ventilation effects. This suggests that burrow systems will not contribute to any significant water storage at depth and, in fact, may enhance the removal of water from the soil.

  11. Comparative evaluation of several small mammal species as monitors of heavy metals, radionuclides, and selected organic compounds in the environment

    SciTech Connect

    Talmage, S.S. Oak Ridge National Lab., TN ); Walton, B.T. )

    1990-08-01

    The primary purpose of this study was to evaluate which small mammal species are the best monitors of specific environmental contaminants. The evaluation is based on the published literature and on an analysis of small mammals trapped at several sites on the Oak Ridge National Laboratory (ORNL) Reservation in Oak Ridge, Tennessee. Studies on the uptake of heavy metals, radionuclides, and organic chemicals are reviewed in Chapter II to evaluate several small mammal species for their capacity to serve as sentinels for the presence, accumulation, and effects of various contaminants. Where several species were present at a site, a comparative evaluation was made and species are ranked for their capacity to serve as monitors of specific contaminants. Food chain accumulation and food habits of the species are used to establish a relationship with suitability as a biomonitor. Tissue-specific concentration factors were noted in order to establish target tissues. Life histories, habitat, and food habits are reviewed in order to make generalizations concerning the ability of similar taxa to serve as biomonitor. Finally, the usefulness of several small mammal species as monitors of three contaminants -- benzo(a)pyrene, mercury, and strontium-90 -- present on or near the ORNL facilities was investigated. 133 refs., 5 figs., 20 tabs.

  12. Decreased small mammal and on-host tick abundance in association with invasive red imported fire ants (Solenopsis invicta).

    PubMed

    Castellanos, Adrian A; Medeiros, Matthew C I; Hamer, Gabriel L; Morrow, Michael E; Eubanks, Micky D; Teel, Pete D; Hamer, Sarah A; Light, Jessica E

    2016-09-01

    Invasive species may impact pathogen transmission by altering the distributions and interactions among native vertebrate reservoir hosts and arthropod vectors. Here, we examined the direct and indirect effects of the red imported fire ant (Solenopsis invicta) on the native tick, small mammal and pathogen community in southeast Texas. Using a replicated large-scale field manipulation study, we show that small mammals were more abundant on treatment plots where S. invicta populations were experimentally reduced. Our analysis of ticks on small mammal hosts demonstrated a threefold increase in the ticks caught per unit effort on treatment relative to control plots, and elevated tick loads (a 27-fold increase) on one common rodent species. We detected only one known human pathogen (Rickettsia parkeri), present in 1.4% of larvae and 6.7% of nymph on-host Amblyomma maculatum samples but with no significant difference between treatment and control plots. Given that host and vector population dynamics are key drivers of pathogen transmission, the reduced small mammal and tick abundance associated with S. invicta may alter pathogen transmission dynamics over broader spatial scales.

  13. Responses of small mammals to habitat fragmentation: epidemiological considerations for rodent-borne hantaviruses in the Americas.

    PubMed

    Rubio, André V; Ávila-Flores, Rafael; Suzán, Gerardo

    2014-12-01

    Rodent-borne hantaviruses are a group of zoonotic agents that cause hemorrhagic fever in humans. The transmission of hantaviruses among rodent hosts may be higher with the increase of reservoir host abundance in a given area (density-dependent transmission) and with the decrease of small mammal diversity (dilution effect phenomenon). These population and community parameters may be modified by habitat fragmentation; however, studies that focus on fragmentation and its effect on hantavirus infection risk are scarce. To further understanding of this issue, we assessed some population and community responses of rodents that may increase the risk for hantavirus transmission among wildlife hosts in the Americas. We conducted a meta-analysis of published studies to assess the responses of small mammals to fragmentation of native habitats, relative to patch size. Our analyses included five countries and 14 case studies for abundance of reservoir hosts (8 species) and 15 case studies for species richness. We found that a reduction of patch area due to habitat fragmentation is associated with increased reservoir host abundances and decreased small mammal richness, which is mainly due to the loss of non-host small mammals. According to these results, habitat fragmentation in the Americas should be considered as an epidemiological risk factor for hantavirus transmission to humans. These findings are important to assess potential risk of infection when fragmentation of native habitats occurs.

  14. Seroepidemiological Survey of Zoonotic Diseases in Small Mammals with PCR Detection of Orientia tsutsugamushi in Chiggers, Gwangju, Korea

    PubMed Central

    Park, Jung Wook; Chung, Jae Keun; Kim, Sun Hee; Cho, Sun Ju; Ha, Yi Deun; Jung, So Hyang; Park, Hye Jung; Song, Hyun Jae; Lee, Jung Yoon; Kim, Dong Min; Pyus, Jah; Ha, Dong Ryong; Kim, Eun Sun; Lee, Jae Il

    2016-01-01

    Serosurveillance for zoonotic diseases in small mammals and detection of chiggers, the vector of Orientia tsutsugamushi, were conducted from September 2014 to August 2015 in Gwangju Metropolitan Area. Apodemus agrarius was the most commonly collected small mammals (158; 91.8%), followed by Myodes regulus (8; 4.6%), and Crocidura lasiura (6; 3.5%). The highest seroprevalence of small mammals for O. tsutsugamushi (41; 26.3%) was followed by hantaviruses (24; 15.4%), Rickettsia spp. (22; 14.1%), and Leptospira (2; 1.3%). A total of 3,194 chiggers were collected from small mammals, and 1,236 of 3,194 chiggers were identified with 7 species of 3 genera: Leptotrombidium scutellare was the most commonly collected species (585; 47.3%), followed by L. orientale (422; 34.1%), Euchoengastia koreaensis (99; 8.0%), L. palpale (58; 4.7%), L. pallidum (36; 2.9%), Neotrombicula gardellai (28; 2.3%), and L. zetum (8; 0.6%). L. scutellare was the predominant species. Three of 1,236 chigger mites were positive for O. tsutsugamushi by PCR. As a result of phylogenetic analysis, the O. tsutsugamushi strain of chigger mites had sequence homology of 90.1-98.2% with Boryong. This study provides baseline data on the distribution of zoonotic diseases and potential vectors for the development of prevention strategies of vector borne diseases in Gwangju metropolitan area. PMID:27417085

  15. Small Mammal Jointed Models to Make, Description Cards, and a Menu of Follow-on Activities in Different Intelligence Areas

    ERIC Educational Resources Information Center

    Rule, Audrey C.; Vander Zanden, Sarah

    2012-01-01

    Instilling an appreciation of nature in our youth is an important precursor to environmental protection and support for sustainability. Research has shown that involving students in environmental projects improves their motivation, skills, and achievement on standardized tests, This document contains images of the body parts of small mammals with…

  16. The interrelationship of mycophagous small mammals and ectomycorrhizal fungi in primeval, disturbed and managed Central European mountainous forests.

    PubMed

    Schickmann, Susanne; Urban, Alexander; Kräutler, Katharina; Nopp-Mayr, Ursula; Hackländer, Klaus

    2012-10-01

    Small forest dwelling mammals are considered to be major consumers and vectors of hypogeous ectomycorrhizal (ECM) fungi, which have lost the ability of active spore discharge. Fungal spore dispersal by mycophagy is deemed an important process involved in forest regeneration, resilience and vitality, primarily based on evidence from Australia and the Pacific Northwestern USA, but is poorly known for Central European mountainous forests thus far. Small mammal mycophagy was investigated by live trapping and microscopical analysis of faecal samples. All small mammal species recorded (Myodes glareolus, Microtus agrestis, Pitymys subterraneus, Apodemus spp., Glis glis, Sorex spp.) had ingested spores of ECM fungi, albeit in varying amounts. My. glareolus was found to be the most important vector of ECM fungal spores, both in quantity and diversity. Species of the genus Sorex seem to play a hitherto underestimated role as dispersers of fungal spores. Glis glis is likely to be an important vector owing to its large home range. Hypogeous ECM basidiomycetes accounted for most spores found in the faecal samples. The frequency of various genera of hypogeous ECM ascomycetes and ECM epigeous fungi was much lower. Comparison with null models indicated a non-random structure of the mycophagy network similar to other mutualistic bipartite networks. Mycophagy can be considered (1) to contribute to nutrition of small forest mammals, (2) to play a pivotal role for forest regeneration and functioning by providing mycorrhizal inoculum to tree seedlings and (3) to be vital for reproduction and diversity of the still poorly known hypogeous fungi.

  17. Long term variations in small mammal composition of a snake diet do not mirror climate change trends

    NASA Astrophysics Data System (ADS)

    Rugiero, Lorenzo; Milana, Giuliano; Capula, Massimo; Amori, Giovanni; Luiselli, Luca

    2012-08-01

    The study of the dietary changes which have intervened over the years in generalist and opportunist predators may provide useful information on the temporal modifications of their prey communities, especially under a climate change scenario. In this study, we analysed the quantitative changes in the small mammal portion of the diet of a generalist and opportunist predator, the asp viper (Vipera aspis) at a forest zone in central Italy, for the period 1987-2010. In addition, small mammals were trapped in five of these years. Apodemus spp., Mus musculus, and Myodes glareolus were the main prey for vipers. Among the various taxa eaten by vipers, only two showed significantly consistent trends over the years, with M. glareolus increasing and Sorex spp. declining in the viper diet. There were no significant relationships between the number of years passed after the first year of sampling and the diversity and dominance indexes of prey composition. We also found a significantly positive relationship between small mammal abundance in the field and their relative frequency of occurrence in the viper's diet, thus demonstrating that vipers really sampled the small mammal species in relation to their local availability. Despite being temperate-zone forest-associated species, hence likely adversed by global warming, Sorex spp. and M. glareolus showed opposite trends over the years, thus suggesting that such trends may reflect more local scale perturbations (local forest overgrowth and diminution of logging).

  18. Decreased small mammal and on-host tick abundance in association with invasive red imported fire ants (Solenopsis invicta)

    PubMed Central

    Medeiros, Matthew C. I.; Hamer, Gabriel L.; Morrow, Michael E.; Eubanks, Micky D.; Teel, Pete D.

    2016-01-01

    Invasive species may impact pathogen transmission by altering the distributions and interactions among native vertebrate reservoir hosts and arthropod vectors. Here, we examined the direct and indirect effects of the red imported fire ant (Solenopsis invicta) on the native tick, small mammal and pathogen community in southeast Texas. Using a replicated large-scale field manipulation study, we show that small mammals were more abundant on treatment plots where S. invicta populations were experimentally reduced. Our analysis of ticks on small mammal hosts demonstrated a threefold increase in the ticks caught per unit effort on treatment relative to control plots, and elevated tick loads (a 27-fold increase) on one common rodent species. We detected only one known human pathogen (Rickettsia parkeri), present in 1.4% of larvae and 6.7% of nymph on-host Amblyomma maculatum samples but with no significant difference between treatment and control plots. Given that host and vector population dynamics are key drivers of pathogen transmission, the reduced small mammal and tick abundance associated with S. invicta may alter pathogen transmission dynamics over broader spatial scales. PMID:27651533

  19. SMALL MAMMALS: CONSEQUENCES OF STOCHASTIC DATA VARIATION FOR MODELING INDICATORS OF HABITAT SUITABILITY FOR A WELL-STUDIED RESOURCE

    EPA Science Inventory

    Increasingly, models of physical habitat variables (i.e. vegetation, soil) are utilized as indicators of small mammal habitat suitability or quality. Presumably, use of physical habitat models indicating habitat suitability or quality would be improved and enhanced by the extens...

  20. Radionuclide Contaminant Analysis of Small Mammals at Area G, Technical Area 54, 1997 (with cumulative summary 1994-1997)

    SciTech Connect

    James R. Biggs; Kathryn D. Bennett; P. R. Fresquez

    1998-12-01

    In 1997, small mammals were sampled at four locations at Area G, Technical Area 54, a control site within the proposed Area G expansion area, and a background site on Frijoles Mesa. The purpose of the sampling was to (1) identify radionuclides that are present within rodent tissues at waste burial sites, (2) compare the amount of radionuclide uptake by small mammals at waste burial sites to a control site, and (3) identifi the primary mode of contamination to small mammals, either through surface contact or ingestion/inhalation. Three composite samples of approximately five animals per sample were collected at each site. Pelts and carcasses of each animal were separated and analyzed independently. Samples were analyzed for 241Am, 90Sr, 238Pu, 239Pu, total U, 137Cs, and 3H. Higher levels of total U and 137CS were detected in pelts as compared to the carcasses of small mammals, and 90Sr was found to be higher in carcasses. Concentrations of other measured radionuclides in carcasses were not found to be statistically different (p< 0.05) from that measured in pelts. However, pelts generally had higher concentrations than carcasses, indicating surface contamination may be the primary contamination mode. Low sample sizes in total number of animals captured during 1997 prevented statistical analysis to compare site to site to all but four sites. Mean concentrations of 241Am, 238Pu, 239Pu, and 3H in small mammal carcasses were found to be statistically greater at the transuranic (TRU) waste pad #2. In addition, mean concentrations of total U, ~lAm, and 3H in pelts of small mammals were also statistically greater. The Control Site and Background Site consistently had the lowest mean concentrations of radionuclides. Year to year comparison of mean radionuclide concentrations was conducted where suftlcient sample size existed. We found 241Am, 238Pu, 239Pu, and 3H mean concentrations in carcasses to be statistically greater in 1997 than previous years at TRU waste pad #2

  1. Effects of Precommercial Thinning and Midstory Control on Avian and Small Mammal Communities during Longleaf Pine Savanna Restoration.

    SciTech Connect

    Lane, Vanessa R; Kilgo, John C

    2015-01-01

    Abstract - Restoring longleaf pine (Pinus palustris Mill.) savanna is a goal of many southern land managers, and longleaf plantations may provide a mechanism for savanna restoration. However, the effects of silvicultural treatments used in the management of longleaf pine plantations on wildlife communities are relatively unknown. Beginning in 1994, we examined effects of longleaf pine restoration with plantation silviculture on avian and small mammal communities using four treatments in four 8- to 11- year-old plantations within the Savannah River Site in South Carolina. Treatments included prescribed burning every 3 to 5 years, plus: (1) no additional treatment (burn-only control); (2) precommercial thinning; (3) non-pine woody control with herbicides; and (4) combined thinning and woody control. We surveyed birds (1996-2003) using 50-m point counts and small mammals with removal trapping. Thinning and woody control alone had short-lived effects on avian communities, and the combination treatment increased avian parameters over the burn-only control in all years. Small mammal abundance showed similar trends as avian abundance for all three treatments when compared with the burn-only control, but only for 2 years post-treatment. Both avian and small mammal communities were temporarily enhanced by controlling woody vegetation with chemicals in addition to prescribed fire and thinning. Therefore, precommercial thinning in longleaf plantations, particularly when combined with woody control and prescribed fire, may benefit early-successional avian and small mammal communities by developing stand conditions more typical of natural longleaf stands maintained by periodic fire.

  2. Modified natural clinoptilolite detoxifies small mammal's organism loaded with lead II: genetic, cell, and physiological effects.

    PubMed

    Topashka-Ancheva, Margarita; Beltcheva, Michaela; Metcheva, Roumiana; Rojas, J Antonio Heredia; Rodriguez-De la Fuente, Abraham O; Gerasimova, Tsvetelina; Rodríguez-Flores, Laura E; Teodorova, Svetla E

    2012-06-01

    The detoxification capacity of the clinoptilolite modification KLS-10-MA used as food additive in small mammals, chronically lead-exposed, was proven for the first time. The modified clinoptilolite was prepared based on natural Bulgarian clinoptilolite deposits. As a powder, it was mechanically mixed at 12.5% concentration with the conventional forage for small rodents. Lead in the form of aqueous solution of Pb(NO(3))(2) was diluted in the drinking water. In the ecotoxicological experiment covering 90 days, imprinting control region laboratory mice were used. They were allocated into four groups: group 1, (control): animals fed with conventional food for small rodents and water; group 2: animals fed with conventional food + clinosorbent KLS-10-MA and water; group 3: animals fed with conventional food and water + Pb(NO(3))(2); and group 4: animals fed with conventional food + KLS-10-MA and water + Pb(NO(3))(2). A group of non-exposed healthy animals was fed with conventional forage mixed with KLS-10-MA to prove eventual toxicity of the sorbent and influence on growth performance. The changes in the chromosome structure, mitotic index, erythrocyte form, erythropoiesis, and body weight gain were recorded. On day 90, the following relations were established: Pb-exposed and clinoptilolite-supplemented mice exhibited 2.3-fold lower chromosome aberrations frequency, 2.5-fold higher mitotic index, and 1.5-fold higher percentage normal erythrocytes 1.3-fold higher body weight compared to Pb-exposed and unsupplemented animals. The obtained data showed that the sorbent is practically non-toxic. The results of the present study encourage a further elaboration of a reliable drug based on the tested substance in the cases of chronic lead intoxication.

  3. Torque patterns of the limbs of small therian mammals during locomotion on flat ground.

    PubMed

    Witte, Hartmut; Biltzinger, Jutta; Hackert, Rémi; Schilling, Nadja; Schmidt, Manuela; Reich, Christian; Fischer, Martin S

    2002-05-01

    In three species of small therian mammals (Scandentia: Tupaia glis, Rodentia: Galea musteloides and Lagomorpha: Ochotona rufescens) the net joint forces and torques acting during stance phase in the four kinematically relevant joints of the forelimbs (scapular pivot, shoulder joint, elbow joint, wrist joint) and the hindlimbs (hip joint, knee joint, ankle joint, intratarsal joint) were determined by inverse dynamic analysis. Kinematics were measured by cineradiography (150 frames s(-1)). Synchronously ground reaction forces were acquired by forceplates. Morphometry of the extremities was performed by a scanning method using structured illumination. The vector sum of ground reaction forces and weight accounts for most of the joint force vector. Inertial effects can be neglected since errors of net joint forces amount at most to 10 %. The general time course of joint torques is comparable for all species in all joints of the forelimb and in the ankle joint. Torques in the intratarsal joints differ between tailed and tail-less species. The torque patterns in the knee and hip joint are unique to each species. For the first time torque patterns are described completely for the forelimb including the scapula as the dominant propulsive segment. The results are compared with the few torque data available for various joints of cats (Felis catus), dogs (Canis lupus f. familiaris), goats (Capra sp.) and horses (Equus przewalskii f. caballus).

  4. Recognition of non-harmonic natural sounds by small mammals using competitive training.

    PubMed

    Ojima, Hisayuki; Taira, Masato; Kubota, Michinori; Horikawa, Junsei

    2012-01-01

    Animals recognize biologically relevant sounds, such as the non-harmonic sounds made by some predators, and respond with adaptive behaviors, such as escaping. To clarify which acoustic parameters are used for identifying non-harmonic, noise-like, broadband sounds, guinea pigs were conditioned to a natural target sound by introducing a novel training procedure in which 2 or 3 guinea pigs in a group competed for food. A set of distinct behavioral reactions was reliably induced almost exclusively to the target sound in a 2-week operant training. When fully conditioned, individual animals were separately tested for recognition of a set of target-like sounds that had been modified from the target sound, with spectral ranges eliminated or with fine or coarse temporal structures altered. The results show that guinea pigs are able to identify the noise-like non-harmonic natural sounds by relying on gross spectral compositions and/or fine temporal structures, just as birds are thought to do in the recognition of harmonic birdsongs. These findings are discussed with regard to similarities and dissimilarities to harmonic sound recognition. The results suggest that similar but not identical processing that requires different time scales might be used to recognize harmonic and non-harmonic sounds, at least in small mammals.

  5. Recognition of Non-Harmonic Natural Sounds by Small Mammals Using Competitive Training

    PubMed Central

    Ojima, Hisayuki; Taira, Masato; Kubota, Michinori; Horikawa, Junsei

    2012-01-01

    Animals recognize biologically relevant sounds, such as the non-harmonic sounds made by some predators, and respond with adaptive behaviors, such as escaping. To clarify which acoustic parameters are used for identifying non-harmonic, noise-like, broadband sounds, guinea pigs were conditioned to a natural target sound by introducing a novel training procedure in which 2 or 3 guinea pigs in a group competed for food. A set of distinct behavioral reactions was reliably induced almost exclusively to the target sound in a 2-week operant training. When fully conditioned, individual animals were separately tested for recognition of a set of target-like sounds that had been modified from the target sound, with spectral ranges eliminated or with fine or coarse temporal structures altered. The results show that guinea pigs are able to identify the noise-like non-harmonic natural sounds by relying on gross spectral compositions and/or fine temporal structures, just as birds are thought to do in the recognition of harmonic birdsongs. These findings are discussed with regard to similarities and dissimilarities to harmonic sound recognition. The results suggest that similar but not identical processing that requires different time scales might be used to recognize harmonic and non-harmonic sounds, at least in small mammals. PMID:23251497

  6. Trophic cascades linking wolves (Canis lupus), coyotes (Canis latrans), and small mammals

    USGS Publications Warehouse

    Miller, B.J.; Harlow, H.J.; Harlow, T.S.; Biggins, D.; Ripple, W.J.

    2012-01-01

    When large carnivores are extirpated from ecosystems that evolved with apex predators, these systems can change at the herbivore and plant trophic levels. Such changes across trophic levels are called cascading effects and they are very important to conservation. Studies on the effects of reintroduced wolves in Yellowstone National Park have examined the interaction pathway of wolves (Canis lupus L., 1758) to ungulates to plants. This study examines the interaction effects of wolves to coyotes to rodents (reversing mesopredator release in the absence of wolves). Coyotes (Canis latrans Say, 1823) generally avoided areas near a wolf den. However, when in the proximity of a den, they used woody habitats (pine or sage) compared with herbaceous habitats (grass or forb or sedge)- when they were away from the wolf den. Our data suggested a significant increase in rodent numbers, particularly voles (genus Microtus Schrank, 1798), during the 3-year study on plots that were within 3 km of the wolf den, but we did not detect a significant change in rodent numbers over time for more distant plots. Predation by coyotes may have depressed numbers of small mammals in areas away from the wolf den. These factors indicate a top-down effect by wolves on coyotes and subsequently on the rodents of the area. Restoration of wolves could be a powerful tool for regulating predation at lower trophic levels.

  7. Spatially heterogeneous impact of climate change on small mammals of montane California

    PubMed Central

    Rowe, Kevin C.; Rowe, Karen M. C.; Tingley, Morgan W.; Koo, Michelle S.; Patton, James L.; Conroy, Chris J.; Perrine, John D.; Beissinger, Steven R.; Moritz, Craig

    2015-01-01

    Resurveys of historical collecting localities have revealed range shifts, primarily leading edge expansions, which have been attributed to global warming. However, there have been few spatially replicated community-scale resurveys testing whether species' responses are spatially consistent. Here we repeated early twentieth century surveys of small mammals along elevational gradients in northern, central and southern regions of montane California. Of the 34 species we analysed, 25 shifted their ranges upslope or downslope in at least one region. However, two-thirds of ranges in the three regions remained stable at one or both elevational limits and none of the 22 species found in all three regions shifted both their upper and lower limits in the same direction in all regions. When shifts occurred, high-elevation species typically contracted their lower limits upslope, whereas low-elevation species had heterogeneous responses. For high-elevation species, site-specific change in temperature better predicted the direction of shifts than change in precipitation, whereas the direction of shifts by low-elevation species was unpredictable by temperature or precipitation. While our results support previous findings of primarily upslope shifts in montane species, they also highlight the degree to which the responses of individual species vary across geographically replicated landscapes. PMID:25621330

  8. Role of edge effect on small mammal populations in a forest fragment

    SciTech Connect

    Wike, L.D.

    2000-06-27

    In many cases, edge effect may determine the distribution and densities of small mammal populations. In 1995 and 1998, a mark and recapture study was conducted at the Savannah River Site (SRS), Aiken, SC, to evaluate the role of forest edge habitat. The area studied was an abandoned home site that had been recently isolated by a timber harvest. Harvest activities left a distinct edge of old field and planted pine contrasting with a relatively xeric, mixed hardwood stand. Trapping was conducted for 17 days in 1995 and 14 days in 1998. Three 30 m by 150 m grids were placed in the clear-cut, edge, and hardwood interior habitats. For both years the principal species captured were Peromyscus gossypinus, P. polionotus, and Neotoma floridana. The edge habitat accounted for approximately 55 percent of all captures and nearly four times as many recaptures as the interior and clear-cut habitats. In 1998, greater numbers of N. floridana were trapped than in 1995. The results indicate that the use of edge habitat can be pronounced even within simple communities. Stewards of managed or restored habitats need to carefully consider the role of edge in these systems. In managed areas such as waste sites, movement of material within the food chain could be reduced by minimizing edge habitat around the points of contamination.

  9. Uptake of environmental contaminants by small mammals in pickleweed habitats at San Francisco Bay, California

    USGS Publications Warehouse

    Clark, D.R.; Foerster, K.S.; Marn, C.M.; Hothem, R.L.

    1992-01-01

    Small mammals were livetrapped in pickleweed (Salicornia virginica) habitats near San Francisco Bay, California in order to measure the uptake of several contaminants and to evaluate the potential effects of these contaminants on the endangered salt marsh harvest mouse (Reithrodontomys raviventris). Tissues of house mice (Mus musculus), deer mice (Peromyscus maniculatus), and California voles (Microtus californicus) from nine sites were analyzed for chemical contaminants including mercury, selenium, cadmium, lead, and polychlorinated biphenyls (PCBs). Concentrations of contaminants differed significantly among sites and species. Mean concentrations at sites where uptake was greatest were less than maximum means for the same or similar species recorded elsewhere. Harvest mice (Reithrodontomys spp.) were captured only at sites where concentrations of mercury or PCBs were below specific levels in house mice. Additional studies aimed at the protection of the salt marsh harvest mouse are suggested. These include contaminant feeding studies in the laboratory as well as field monitoring of surrogate species and community structure in salt marsh harvest mouse habitats.

  10. Molecular Survey of Zoonotic Agents in Rodents and Other Small Mammals in Croatia.

    PubMed

    Tadin, Ante; Tokarz, Rafal; Markotić, Alemka; Margaletić, Josip; Turk, Nenad; Habuš, Josipa; Svoboda, Petra; Vucelja, Marko; Desai, Aaloki; Jain, Komal; Lipkin, W Ian

    2016-02-01

    Croatia is a focus for many rodent-borne zoonosis. Here, we report a survey of 242 rodents and small mammals, including 43 Myodes glareolus, 131 Apodemus flavicollis, 53 Apodemus agrarius, three Apodemus sylvaticus, six Sorex araneus, four Microtus arvalis, one Microtus agrestis, and one Muscardinus avellanarius, collected at eight sites in Croatia over an 8-year period. Multiplex MassTag polymerase chain reaction (PCR) was used for detection of Borrelia, Rickettsia, Bartonella, Babesia, Ehrlichia, Anaplasma, Francisella tularensis, and Coxiella burnetii. Individual PCR assays were used for detection of Leptospira, lymphocytic choriomeningitis virus, orthopoxviruses, flaviviruses, hantaviruses, and Toxoplasma gondii. Of the rodents, 52 (21.5%) were infected with Leptospira, 9 (3.7%) with Borrelia miyamotoi, 5 (2%) with Borrelia afzelii, 29 (12.0%) with Bartonella, 8 (3.3%) with Babesia microti, 2 (0.8%) with Ehrlichia, 4 (1.7%) with Anaplasma, 2 (0.8%) with F. tularensis, 43 (17.8%) with hantaviruses, and 1 (0.4%) with an orthopoxvirus. Other agents were not detected. Multiple infections were found in 32 rodents (13.2%): dual infections in 26 rodents (10.7%), triple infections in four rodents (2.9%), and quadruple infections in two rodents (0.8%). Our findings indicate that rodents in Croatia harbor a wide range of bacteria and viruses that are pathogenic to humans.

  11. Molecular Survey of Zoonotic Agents in Rodents and Other Small Mammals in Croatia

    PubMed Central

    Tadin, Ante; Tokarz, Rafal; Markotić, Alemka; Margaletić, Josip; Turk, Nenad; Habuš, Josipa; Svoboda, Petra; Vucelja, Marko; Desai, Aaloki; Jain, Komal; Ian Lipkin, W.

    2016-01-01

    Croatia is a focus for many rodent-borne zoonosis. Here, we report a survey of 242 rodents and small mammals, including 43 Myodes glareolus, 131 Apodemus flavicollis, 53 Apodemus agrarius, three Apodemus sylvaticus, six Sorex araneus, four Microtus arvalis, one Microtus agrestis, and one Muscardinus avellanarius, collected at eight sites in Croatia over an 8-year period. Multiplex MassTag polymerase chain reaction (PCR) was used for detection of Borrelia, Rickettsia, Bartonella, Babesia, Ehrlichia, Anaplasma, Francisella tularensis, and Coxiella burnetii. Individual PCR assays were used for detection of Leptospira, lymphocytic choriomeningitis virus, orthopoxviruses, flaviviruses, hantaviruses, and Toxoplasma gondii. Of the rodents, 52 (21.5%) were infected with Leptospira, 9 (3.7%) with Borrelia miyamotoi, 5 (2%) with Borrelia afzelii, 29 (12.0%) with Bartonella, 8 (3.3%) with Babesia microti, 2 (0.8%) with Ehrlichia, 4 (1.7%) with Anaplasma, 2 (0.8%) with F. tularensis, 43 (17.8%) with hantaviruses, and 1 (0.4%) with an orthopoxvirus. Other agents were not detected. Multiple infections were found in 32 rodents (13.2%): dual infections in 26 rodents (10.7%), triple infections in four rodents (2.9%), and quadruple infections in two rodents (0.8%). Our findings indicate that rodents in Croatia harbor a wide range of bacteria and viruses that are pathogenic to humans. PMID:26711522

  12. Preliminary small mammal taphonomy of FLK NW level 20 (Olduvai Gorge, Tanzania)

    NASA Astrophysics Data System (ADS)

    Arcos, Saleta; Sevilla, Paloma; Fernández-Jalvo, Yolanda

    2010-11-01

    The Bed-I series of Olduvai Gorge (Tanzania) is a reference site in human evolution, having yielded the holotypes of Paranthropus boisei and Homo habilis, together with manufactured artefacts and abundant large and micro-fauna. Excavations in Olduvai Gorge have been recently resumed, with new aims and new results. This paper presents the results of the taphonomic analysis carried out on a fossil small-mammal assemblage recovered from FLK NW level 20, a layer overlying Tuff C, dated from 1.84 Ma. The analysis provides good evidence of a category 1 predator, most likely a barn owl, as the predator of the bone assemblage. Trampling and sediment compression might influence postdepositional breakage of the bones. This study is especially relevant since previous taphonomic analyses carried out at levels above and below this sample led to inconclusive results due to a low number of fossils ( Fernández-Jalvo et al., 1998). The new sample provides new information to reconstruct the paleoenvironmental context in which early hominins inhabited.

  13. Bacterial production in the water column of small streams highly depends on terrestrial dissolved organic carbon

    NASA Astrophysics Data System (ADS)

    Graeber, Daniel; Poulsen, Jane R.; Rasmussen, Jes J.; Kronvang, Brian; Zak, Dominik; Kamjunke, Norbert

    2016-04-01

    In the recent years it has become clear that the largest part of the terrestrial dissolved organic carbon (DOC) pool is removed on the way from the land to the ocean. Yet it is still unclear, where in the freshwater systems terrestrial DOC is actually taken up, and for streams DOC uptake was assumed to happen mostly at the stream bottom (benthic zone). However, a recent monitoring study implies that water column but not benthic bacteria are strongly affected by the amount and composition of DOM entering streams from the terrestrial zone. We conducted an experiment to compare the reaction of the bacterial production and heterotrophic uptake in the water column and the benthic zone to a standardized source of terrestrial DOC (leaf leachate from Beech litter). In detail, we sampled gravel and water from eight streams with a gradient in stream size and land use. For each stream four different treatments were incubated at 16°C for three days and each stream: filtered stream water with gravel stones (representing benthic zone bacteria) or unfiltered stream water (representing water column bacteria), both either with (n = 5) or, without (n = 3) leaf leachate. We found that the bacterial uptake of leaf litter DOC was higher for the benthic zone likely due to the higher bacterial production compared to the water column. In contrast, the bacterial production per amount of leaf leachate DOC taken up was significantly higher for the bacteria in the water column than for those in the benthic zone. This clearly indicates a higher growth efficiency with the leaf leachate DOC for the bacteria in the water column than in the benthic zone. We found a high variability for the growth efficiency in the water column, which was best explained by a negative correlation of the DOC demand with stream width (R² = 0.86, linear correlation of log-transformed data). This was not the case for the benthic zone bacteria (R² = 0.02). This implies that water column bacteria in very small streams

  14. Climate Change Risks and Conservation Implications for a Threatened Small-Range Mammal Species

    PubMed Central

    Morueta-Holme, Naia; Fløjgaard, Camilla; Svenning, Jens-Christian

    2010-01-01

    Background Climate change is already affecting the distributions of many species and may lead to numerous extinctions over the next century. Small-range species are likely to be a special concern, but the extent to which they are sensitive to climate is currently unclear. Species distribution modeling, if carefully implemented, can be used to assess climate sensitivity and potential climate change impacts, even for rare and cryptic species. Methodology/Principal Findings We used species distribution modeling to assess the climate sensitivity, climate change risks and conservation implications for a threatened small-range mammal species, the Iberian desman (Galemys pyrenaicus), which is a phylogenetically isolated insectivore endemic to south-western Europe. Atlas data on the distribution of G. pyrenaicus was linked to data on climate, topography and human impact using two species distribution modeling algorithms to test hypotheses on the factors that determine the range for this species. Predictive models were developed and projected onto climate scenarios for 2070–2099 to assess climate change risks and conservation possibilities. Mean summer temperature and water balance appeared to be the main factors influencing the distribution of G. pyrenaicus. Climate change was predicted to result in significant reductions of the species' range. However, the severity of these reductions was highly dependent on which predictor was the most important limiting factor. Notably, if mean summer temperature is the main range determinant, G. pyrenaicus is at risk of near total extinction in Spain under the most severe climate change scenario. The range projections for Europe indicate that assisted migration may be a possible long-term conservation strategy for G. pyrenaicus in the face of global warming. Conclusions/Significance Climate change clearly poses a severe threat to this illustrative endemic species. Our findings confirm that endemic species can be highly vulnerable to

  15. Ecological risk assessment for small omnivorous mammals exposed to polycyclic aromatic hydrocarbons: a case study in northeastern Mexico.

    PubMed

    Flores-Serrano, Rosa María; Iturbe-Argüelles, Rosario; Pérez-Casimiro, Guillermina; Ramírez-González, Adriana; Flores-Guido, José Salvador; Kantún-Balam, Jesús Martín

    2014-04-01

    An ecological risk assessment (ERA) was performed using the hazard quotient (HQ) method to evaluate the risks of oral exposure to polycyclic aromatic hydrocarbons (PAHs) for medium sized omnivorous mammals. This is the first in a series of three papers. In Mexico there is little experience in performing this kind of assessment for the terrestrial compartment, in particular for birds and mammals exposed to hydrocarbons. The purpose of this paper is to perform an ERA and to establish if the omnivorous mammalian species living in the area are at risk of adverse effects. The studied site is a land that in past years had been used for the disposition of petroleum tank bottom sludges, and scrap metals. Soil and water samples were collected and analyzed, and we obtained a list of the site's wildlife species as well as samples of the specimens, which were analyzed also. HQs were calculated for the hydrocarbons identified as chemicals of potential ecological concern (COPECs) and the omnivorous mammals of the site were evaluated. Toxicity reference values (TRVs) were taken from the appropriate literature, and the doses of exposure were estimated considering the ingestion of water, soil, and diet. Results indicated that potential risks associated to the oral exposure route were less than benchmarks for effects (in all cases HQ<1). The methodology is adequate in terms of the parameters considered in the calculations, but it was concluded that in order to reduce uncertainty, more research is required in Mexico. This should be primarily aimed at obtaining TRVs for mammals, and consider test species with body weights more similar to those found in the local fauna.

  16. Environmental Survey Report for ORNL: Small Mammal Abundance and Distribution Survey Oak Ridge National Environmental Research Park 2009 - 2010

    SciTech Connect

    Giffen, Neil R; Reasor, R. Scott; Campbell, Claire L.

    2009-12-01

    This report summarizes a 1-year small mammal biodiversity survey conducted on the Oak Ridge National Environmental Research Park (OR Research Park). The task was implemented through the Oak Ridge National Laboratory (ORNL) Natural Resources Management Program and included researchers from the ORNL Environmental Sciences Division, interns in the Oak Ridge Institute for Science and Education Higher Education Research Experiences Program, and ORNL Environmental Protection Services staff. Eight sites were surveyed reservation wide. The survey was conducted in an effort to determine species abundance and diversity of small mammal populations throughout the reservation and to continue the historical inventory of small mammal presence for biodiversity records. This data collection effort was in support of the approved Wildlife Management Plan for the Oak Ridge Reservation, a major goal of which is to maintain and enhance wildlife biodiversity on the Reservation. Three of the sites (Poplar Creek, McNew Hollow, and Deer Check Station Field) were previously surveyed during a major natural resources inventory conducted in 1996. Five new sites were included in this study: Bearden Creek, Rainy Knob (Natural Area 21), Gum Hollow, White Oak Creek and Melton Branch. The 2009-2010 small mammal surveys were conducted from June 2009 to July 2010 on the Oak Ridge National Environmental Research Park (OR Research Park). The survey had two main goals: (1) to determine species abundance and diversity and (2) to update historical records on the OR Research Park. The park is located on the Department of Energy-owned Oak Ridge Reservation, which encompasses 13,580 ha. The primary focus of the study was riparian zones. In addition to small mammal sampling, vegetation and coarse woody debris samples were taken at certain sites to determine any correlations between habitat and species presence. During the survey all specimens were captured and released using live trapping techniques including

  17. Context-dependent effects of large-wildlife declines on small-mammal communities in central Kenya.

    PubMed

    Young, Hillary S; McCauley, Douglas J; Dirzo, Rodolfo; Goheen, Jacob R; Agwanda, Bernard; Brook, Cara; Otarola-Castillo, Erik; Ferguson, Adam W; Kinyua, Stephen N; McDonough, Molly M; Palmer, Todd M; Pringle, Robert M; Young, Truman P; Helgen, Kristofer M

    2015-03-01

    Many species of large wildlife have declined drastically worldwide. These reductions often lead to profound shifts in the ecology of entire communities and ecosystems. However, the effects of these large-wildlife declines on other taxa likely hinge upon both underlying abiotic properties of these systems and on the types of secondary anthropogenic changes associated with wildlife loss, making impacts difficult to predict. To better understand how these important contextual factors determine the consequences of large-wildlife declines on other animals in a community, we examined the effects of three common forms of large-wildlife loss (removal without replacement [using fences], removal followed by replacement with domestic stock, and removal accompanied by crop agricultural use) on small-mammal abundance, diversity, and community composition, in landscapes that varied in several abiotic attributes (rainfall, soil fertility, land-use intensity) in central Kenya. We found that small-mammal communities were indeed heavily impacted by all forms of large-wildlife decline, showing, on average: (1) higher densities, (2) lower species richness per site, and (3) different species assemblages in sites from which large wildlife were removed. However, the nature and magnitude of these effects were strongly context dependent. Rainfall, type of land-use change, and the interaction of these two factors were key predictors of both the magnitude and type of responses of small mammals. The strongest effects, particularly abundance responses, tended to be observed in low-rainfall areas. Whereas isolated wildlife removal primarily led to increased small-mammal abundance, wildlife removal associated with secondary uses (agriculture, domestic stock) had much more variable effects on abundance and stronger impacts on diversity and composition. Collectively, these results (1) highlight the importance of context in determining the impacts of large-wildlife decline on small-mammal

  18. Radiocarbon dating late Quaternary loess deposits using small terrestrial gastropod shells

    USGS Publications Warehouse

    Pigati, Jeff S.; McGeehin, John P.; Muhs, Daniel R.; Bettis, E. Arthur

    2013-01-01

    Constraining the ages and mass accumulation rates of late Quaternary loess deposits is often difficult because of the paucity of organic material typically available for 14C dating and the inherent limitations of luminescence techniques. Radiocarbon dating of small terrestrial gastropod shells may provide an alternative to these methods as fossil shells are common in loess and contain ∼12% carbon by weight. Terrestrial gastropod assemblages in loess have been used extensively to reconstruct past environmental conditions but have been largely ignored for dating purposes. Here, we present the results of a multi-faceted approach to understanding the potential for using small terrestrial gastropod shells to date loess deposits in North America. First, we compare highly resolved 14C ages of well-preserved wood and gastropod shells (Succineidae) recovered from a Holocene loess section in Alaska. Radiocarbon ages derived from the shells are nearly identical to wood and plant macrofossil ages throughout the section, which suggests that the shells behaved as closed systems with respect to carbon for at least the last 10 ka (thousands of calibrated 14C years before present). Second, we apply 14C dating of gastropod shells to late Pleistocene loess deposits in the Great Plains using stratigraphy and independent chronologies for comparison. The new shell ages require less interpretation than humic acid radiocarbon ages that are commonly used in loess studies, provide additional stratigraphic coverage to previous dating efforts, and are in correct stratigraphic order more often than their luminescence counterparts. Third, we show that Succineidae shells recovered from historic loess in the Matanuska River Valley, Alaska captured the 20th century 14C bomb spike, which suggests that the shells can be used to date late Holocene and historic-aged loess. Finally, results from Nebraska and western Iowa suggest that, similar to other materials, shell ages approaching ∼40 ka should

  19. Comparative sensitivity of small mammals to micronucleus induction in bone marrow cells by clastogenic compounds

    SciTech Connect

    Meier, J.R.; Wernsing, P.; Daniel, F.B.; Torsella, J.

    1995-12-31

    The bone marrow micronucleus assay is the most widely used method for detecting genetic damage in vivo, but this assay has received little attention for its possible application to biomonitoring terrestrial environments. The present study compared the responsiveness of three small mammalian species, Cryptotus parva (least shrew), Peromyscus leucopus (white-footed mouse), and strain CD-1 Mus musculus (house mouse), to the clastogen, methylmethanesulfonate (MMS). Five animals of each sex of each species were exposed for 24 h to four concentrations of MMS ranging from 0 to 50 mg/kg. Bone marrow cells were flushed from the femurs, and smears were stained with acridine orange and examined using fluorescence microscopy. The slides were scored for evidence of acute bone marrow toxicity (polychromatic to normochromatic erythrocyte ratio, PCE:NCE) and frequency of micronucleated PCE. PCE:NCE was depressed at 50 mg/kg in P. leucopus, but not in the other species. Dose-related increases in micronucleated PCE were observed in all three species, with males being more sensitive for P. leucopus and M. musculus, and females being more sensitive for C. parva. For both sexes, the two feral species, P. leucopus and C. parva, were more sensitive than M. musculus. These studies demonstrate the successful application of the bone marrow micronucleus assay to species other than standard laboratory strains of mice. The results also demonstrate heretofore unrecognized species differences in responsiveness.

  20. Innovation in Deep Space Habitat Interior Design: Lessons Learned From Small Space Design in Terrestrial Architecture

    NASA Technical Reports Server (NTRS)

    Simon, Matthew A.; Toups, Larry

    2014-01-01

    Increased public awareness of carbon footprints, crowding in urban areas, and rising housing costs have spawned a 'small house movement' in the housing industry. Members of this movement desire small, yet highly functional residences which are both affordable and sensitive to consumer comfort standards. In order to create comfortable, minimum-volume interiors, recent advances have been made in furniture design and approaches to interior layout that improve both space utilization and encourage multi-functional design for small homes, apartments, naval, and recreational vehicles. Design efforts in this evolving niche of terrestrial architecture can provide useful insights leading to innovation and efficiency in the design of space habitats for future human space exploration missions. This paper highlights many of the cross-cutting architectural solutions used in small space design which are applicable to the spacecraft interior design problem. Specific solutions discussed include reconfigurable, multi-purpose spaces; collapsible or transformable furniture; multi-purpose accommodations; efficient, space saving appliances; stowable and mobile workstations; and the miniaturization of electronics and computing hardware. For each of these design features, descriptions of how they save interior volume or mitigate other small space issues such as confinement stress or crowding are discussed. Finally, recommendations are provided to provide guidance for future designs and identify potential collaborations with the small spaces design community.

  1. Operating a terrestrial Internet router onboard and alongside a small satellite

    NASA Astrophysics Data System (ADS)

    Wood, L.; da Silva Curiel, A.; Ivancic, W.; Hodgson, D.; Shell, D.; Jackson, C.; Stewart, D.

    2006-07-01

    After twenty months of flying, testing and demonstrating a Cisco mobile access router, originally designed for terrestrial use, onboard the low-Earth-orbiting UK-DMC satellite as part of a larger merged ground/space IP-based internetwork, we use our experience to examine the benefits and drawbacks of integration and standards reuse for small satellite missions. Benefits include ease of operation and the ability to leverage existing systems and infrastructure designed for general use with a large set of latent capabilities to draw on when needed, as well as the familiarity that comes from reuse of existing, known, and well-understood security and operational models. Drawbacks include cases where integration work was needed to bridge the gaps in assumptions between different systems, and where performance considerations outweighed the benefits of reuse of pre-existing file transfer protocols. We find similarities with the terrestrial IP networks whose technologies have been taken to small satellites—and also some significant differences between the two in operational models and assumptions that must be borne in mind.

  2. Tracking small mountainous river derived terrestrial organic carbon across the active margin marine environment

    NASA Astrophysics Data System (ADS)

    Childress, L. B.; Blair, N. E.; Orpin, A. R.

    2015-12-01

    Active margins are particularly efficient in the burial of organic carbon due to the close proximity of highland sources to marine sediment sinks and high sediment transport rates. Compared with passive margins, active margins are dominated by small mountainous river systems, and play a unique role in marine and global carbon cycles. Small mountainous rivers drain only approximately 20% of land, but deliver approximately 40% of the fluvial sediment to the global ocean. Unlike large passive margin systems where riverine organic carbon is efficiently incinerated on continental shelves, small mountainous river dominated systems are highly effective in the burial and preservation of organic carbon due to the rapid and episodic delivery of organic carbon sourced from vegetation, soil, and rock. To investigate the erosion, transport, and burial of organic carbon in active margin small mountainous river systems we use the Waipaoa River, New Zealand. The Waipaoa River, and adjacent marine depositional environment, is a system of interest due to a large sediment yield (6800 tons km-2 yr-1) and extensive characterization. Previous studies have considered the biogeochemistry of the watershed and tracked the transport of terrestrially derived sediment and organics to the continental shelf and slope by biogeochemical proxies including stable carbon isotopes, lignin phenols, n-alkanes, and n-fatty acids. In this work we expand the spatial extent of investigation to include deep sea sediments of the Hikurangi Trough. Located in approximately 3000 m water depth 120 km from the mouth of the Waipaoa River, the Hikurangi Trough is the southern extension of the Tonga-Kermadec-Hikurangi subduction system. Piston core sediments collected by the National Institute of Water and Atmospheric Research (NIWA, NZ) in the Hikurangi Trough indicate the presence of terrestrially derived material (lignin phenols), and suggest a continuum of deposition, resuspension, and transport across the margin

  3. Morphological and molecular analyses of larval taeniid species in small mammals from contrasting habitats in Denmark.

    PubMed

    Al-Sabi, M N S; Jensen, P M; Christensen, M U; Kapel, C M O

    2015-01-01

    Taeniid infections in intermediate hosts manifest themselves as extraintestinal larval stages which, in early development, lack species-specific characteristics. The inability to distinguish infections of zoonotic importance such as Echinococcus multilocularis from other taeniid infections that have mainly veterinary significance stimulated the development of species-specific molecular diagnostics. In this study, the prevalence of taeniid infections in potential intermediate hosts was evaluated using both morphological diagnosis and a newly described multiplex polymerase chain reaction (PCR) for species determination. Small mammals (N= 719) were trapped in three different types of habitats in north-east Zealand, Denmark. The sensitivity of the multiplex PCR (90.5%) exceeded that of morphological examination (57.9%) for identifying 95 taeniid infections. The use of the multiplex PCR resulted in higher prevalence rates due to improved detection of immature liver infections with Hydatigera taeniaeformis and Versteria mustelae, but did not affect the observed prevalence rates of peritoneal metacestodes of Taenia polyacantha. The prevalence of taeniid infections showed a significant difference according to habitat type, potentially identifying a 'sylvatic' transmission and an 'urban' transmission, with marked variation among different taeniid species. Versteria mustelae and T. polyacantha were more prevalent in rural forests, while infections with H. taeniaeformis were dominant in urban parks/forests and in residential and farm gardens. The multiplex PCR facilitated a better utilization of wildlife samples by yielding a higher number of definitive diagnoses of ambiguous taeniid infections in liver lesions, allowing for more accurate epidemiological data and, hence, a more accurate risk assessment.

  4. Ancient Urban Ecology Reconstructed from Archaeozoological Remains of Small Mammals in the Near East

    PubMed Central

    Weissbrod, Lior; Malkinson, Dan; Cucchi, Thomas; Gadot, Yuval; Finkelstein, Israel; Bar-Oz, Guy

    2014-01-01

    Modern rapidly expanding cities generate intricate patterns of species diversity owing to immense complexity in urban spatial structure and current growth trajectories. We propose to identify and uncouple the drivers that give rise to these patterns by looking at the effect of urbanism on species diversity over a previously unexplored long temporal frame that covers early developments in urbanism. To provide this historical perspective we analyzed archaeozoological remains of small mammals from ancient urban and rural sites in the Near East from the 2nd to the 1st millennium BCE, and compared them to observations from modern urban areas. Our data show that ancient urban assemblages consistently comprised two main taxa (Mus musculus domesticus and Crocidura sp.), whereas assemblages of contemporaneous rural sites were significantly richer. Low species diversity also characterizes high-density core areas of modern cities, suggesting that similar ecological drivers have continued to operate in urban areas despite the vast growth in their size and population densities, as well as in the complexity of their technologies and social organization. Research in urban ecology has tended to emphasize the relatively high species diversity observed in low-density areas located on the outskirts of cities, where open and vegetated patches are abundant. The fact that over several millennia urban evolution did not significantly alter species diversity suggests that low diversity is an attribute of densely-populated settlements. The possibility that high diversity in peripheral urban areas arose only recently as a short-term phenomenon in urban ecology merits further research based on long-term data. PMID:24622726

  5. Ancient urban ecology reconstructed from archaeozoological remains of small mammals in the Near East.

    PubMed

    Weissbrod, Lior; Malkinson, Dan; Cucchi, Thomas; Gadot, Yuval; Finkelstein, Israel; Bar-Oz, Guy

    2014-01-01

    Modern rapidly expanding cities generate intricate patterns of species diversity owing to immense complexity in urban spatial structure and current growth trajectories. We propose to identify and uncouple the drivers that give rise to these patterns by looking at the effect of urbanism on species diversity over a previously unexplored long temporal frame that covers early developments in urbanism. To provide this historical perspective we analyzed archaeozoological remains of small mammals from ancient urban and rural sites in the Near East from the 2nd to the 1st millennium BCE, and compared them to observations from modern urban areas. Our data show that ancient urban assemblages consistently comprised two main taxa (Mus musculus domesticus and Crocidura sp.), whereas assemblages of contemporaneous rural sites were significantly richer. Low species diversity also characterizes high-density core areas of modern cities, suggesting that similar ecological drivers have continued to operate in urban areas despite the vast growth in their size and population densities, as well as in the complexity of their technologies and social organization. Research in urban ecology has tended to emphasize the relatively high species diversity observed in low-density areas located on the outskirts of cities, where open and vegetated patches are abundant. The fact that over several millennia urban evolution did not significantly alter species diversity suggests that low diversity is an attribute of densely-populated settlements. The possibility that high diversity in peripheral urban areas arose only recently as a short-term phenomenon in urban ecology merits further research based on long-term data.

  6. Species diversity, selectivity, and habitat associations of small mammals from coastal California

    USGS Publications Warehouse

    Fellers, Gary M.

    1994-01-01

    Species diversity and habitat associations were documented for small mammals along 16 transects in a semiarid part of coastal California. Peromyscus were the most abundant, comprising 45.3% of all captures, followed by Dipodomys (21.2%), Neotoma (15.1%), and Perognathus (15.0%). Five additional genera made up the remaining captures (3.4%). Peromyscus truei and Perognathus californicus were both common and widespread, accounting for 42.1% of all captures. Both species were found on all but one transect. Neotoma lepida, the third most common species, was captured on rock transects 96% of the time. Dipodomys elephantinus was the fifth most common species, and was found exclusively in chamise chaparral. Species diversity (H') averaged 1.22 and ranged from 0.33 on a chamise chaparral transect to 1.74 on another chamise chaparral transect which crossed the edge of a burn. Nearly all transects demonstrated this same trend for diversity to vary widely both within and between habitats, indicating that local conditions were more of an influence on diversity than broad habitat types. Selectivity, averaged across the ten most common species, was only 0.06, indicating that habitat selectivity was quite low. The most geographically widespread species, Peromyscus maniculatus, was the least selective (0.03), whereas the two species with the smallest geographic ranges, D. venustus and D. elephantinus, showed the greatest habitat selectivity (0.11 and 0.20, respectively). These values are much lower than those reported from short-term studies and suggest that, like species diversity, brief studies may not accurately reflect community-level interactions.

  7. Losing ground: past history and future fate of Arctic small mammals in a changing climate.

    PubMed

    Prost, Stefan; Guralnick, Robert P; Waltari, Eric; Fedorov, Vadim B; Kuzmina, Elena; Smirnov, Nickolay; van Kolfschoten, Thijs; Hofreiter, Michael; Vrieling, Klaas

    2013-06-01

    According to the IPCC, the global average temperature is likely to increase by 1.4-5.8 °C over the period from 1990 to 2100. In Polar regions, the magnitude of such climatic changes is even larger than in temperate and tropical biomes. This amplified response is particularly worrisome given that the so-far moderate warming is already impacting Arctic ecosystems. Predicting species responses to rapid warming in the near future can be informed by investigating past responses, as, like the rest of the planet, the Arctic experienced recurrent cycles of temperature increase and decrease (glacial-interglacial changes) in the past. In this study, we compare the response of two important prey species of the Arctic ecosystem, the collared lemming and the narrow-skulled vole, to Late Quaternary climate change. Using ancient DNA and Ecological Niche Modeling (ENM), we show that the two species, which occupy similar, but not identical ecological niches, show markedly different responses to climatic and environmental changes within broadly similar habitats. We empirically demonstrate, utilizing coalescent model-testing approaches, that collared lemming populations decreased substantially after the Last Glacial Maximum; a result consistent with distributional loss over the same period based on ENM results. Given this strong association, we projected the current niche onto future climate conditions based on IPCC 4.0 scenarios, and forecast accelerating loss of habitat along southern range boundaries with likely associated demographic consequences. Narrow-skulled vole distribution and demography, by contrast, was only moderately impacted by past climatic changes, but predicted future changes may begin to affect their current western range boundaries. Our work, founded on multiple lines of evidence suggests a future of rapidly geographically shifting Arctic small mammal prey communities, some of whom are on the edge of existence, and whose fate may have ramifications for the

  8. Evaluating abundance estimate precision and the assumptions of a count-based index for small mammals

    USGS Publications Warehouse

    Wiewel, A.S.; Adams, A.A.Y.; Rodda, G.H.

    2009-01-01

    Conservation and management of small mammals requires reliable knowledge of population size. We investigated precision of markrecapture and removal abundance estimates generated from live-trapping and snap-trapping data collected at sites on Guam (n 7), Rota (n 4), Saipan (n 5), and Tinian (n 3), in the Mariana Islands. We also evaluated a common index, captures per unit effort (CPUE), as a predictor of abundance. In addition, we evaluated cost and time associated with implementing live-trapping and snap-trapping and compared species-specific capture rates of selected live- and snap-traps. For all species, markrecapture estimates were consistently more precise than removal estimates based on coefficients of variation and 95 confidence intervals. The predictive utility of CPUE was poor but improved with increasing sampling duration. Nonetheless, modeling of sampling data revealed that underlying assumptions critical to application of an index of abundance, such as constant capture probability across space, time, and individuals, were not met. Although snap-trapping was cheaper and faster than live-trapping, the time difference was negligible when site preparation time was considered. Rattus diardii spp. captures were greatest in Haguruma live-traps (Standard Trading Co., Honolulu, HI) and Victor snap-traps (Woodstream Corporation, Lititz, PA), whereas Suncus murinus and Mus musculus captures were greatest in Sherman live-traps (H. B. Sherman Traps, Inc., Tallahassee, FL) and Museum Special snap-traps (Woodstream Corporation). Although snap-trapping and CPUE may have utility after validation against more rigorous methods, validation should occur across the full range of study conditions. Resources required for this level of validation would likely be better allocated towards implementing rigorous and robust methods.

  9. Long-term data set of small mammals from owl pellets in the Atlantic-Mediterranean transition area.

    PubMed

    Escribano, Nora; Galicia, David; Ariño, Arturo H; Escala, Carmen

    2016-09-27

    We describe the pellet sampling data set from the Vertebrate Collection of the Museum of Zoology of the University of Navarra. This data set compiles all information about small mammals obtained from the analysis of owl pellets. The collection consists on skulls, mandibles, and some skeletons of 36 species of more than 72,000 georeferenced specimens. These specimens come from the Iberian Peninsula although most samples were collected in Navarra, a highly diverse transitional area of 10,000 kilometre square sitting across three biogeographical regions. The collection spans more than forty years and is still growing as a result of the establishment of a barn owl pellet monitoring network in 2015. The program will provide critical information about the evolution of the small mammals' community in this transition zone as it changes over time.

  10. Chemical composition of the small mammal reproductive system as an indicator of enterprise technogenic impact on the environment

    NASA Astrophysics Data System (ADS)

    Baranovskaya, N.; Belyanovskaya, A.; Bezel, V.; Mukhacheva, S.; Anufrieva, M.

    2016-09-01

    In this paper we consider the indicative role of chemical composition of the small mammal (specifically, the bank vole, or Myodes glareolus) reproductive system with the purpose of studying the impact of a large-scale nonferrous metal-processing enterprise on living organisms through the expample of Middle Ural copper-smelting plant OJSC. We have analysed the chemical composition of the placenta-embryo system in the areas which are 2 km and 30 km away from the plant.

  11. How does landscape use influence small mammal diversity, abundance and biomass in hedgerow networks of farming landscapes?

    NASA Astrophysics Data System (ADS)

    Michel, Nadia; Burel, Françoise; Butet, Alain

    2006-07-01

    Over the last decades, profound changes in agricultural practices in the world have led to modifications of land-use as well as landscape structure and composition. Major changes resulted in enlargement of parcel size, increase of cultivated areas and drastic reduction of permanent elements such as woods, hedges or natural meadows. In this context we chose to investigate the composition and structure of small mammal communities in the hedgerow networks of three landscape units of Western France (Brittany) differing by their level of agricultural land-use intensity and hedgerow network density: a slightly intensified dense hedgerow network landscape unit (BOC1), a moderately intensified and fragmented hedgerow network landscape unit (BOC2) and a highly intensified landscape unit on an area reclaimed from the sea (POL). Characterization of small mammal communities was performed using live trapping on permanent habitats (eight hedges per landscape unit). In each of the 24 trapping units, a standardized method was used consisting of a baited 100-m trap-line. Diversity indices were used to compare the three communities. Species richness didn't vary across landscapes whereas Shannon's index of diversity underlined a clear difference between, on the one hand, the most intensified landscape unit (POL) which displayed the lowest diversity and, on the other hand, the two other less intensified units. The abundance of small mammals differed between the three sites: they were significantly more numerous in the hedges of the most intensified site than in hedges of the two other sites. Differences between species also appeared: for example, the Bank vole ( Clethrionomys glareolus) was very characteristic of POL, whereas the Pygmy shrew ( Sorex minutus) was much more associated with BOC sites. Within hedges, like for abundance, small mammal biomass was the highest in the most intensified site (POL > BOC2 = BOC1). On the contrary, at the landscape scale, biomass was the lowest in

  12. [Characteristics of zonal distribution of the gamasid mites connected with small mammals and their nests in Western Siberia].

    PubMed

    Mal'kova, M G

    2010-01-01

    Analysis of long-term data on the fauna, landscape distribution, and structure of communities of the gamasid mites (Acari:Parasitiformes:Mesostigmata) connected with small mammals and their nests in the plain part of Western Siberia is carried out. By now, presence of 249 gamasid mite species is established in the territory under study, including 193 free-living and 56 parasitic species. Gamasid mites are represented by the maximal number of species on small mammals and in thers nests in northern forest-steppe (102 and 105 species respectively). Nine parasitic species from two ecological groups (epizoic and nidicolous) were found in all landscape zones of the West Siberian Plain, namely: 1) epizoic species Laelaps clethrionomydis Lange, 1955, Laelaps hilaris C. L. Koch, 1836, and Hyperlaelaps arvalis Zachvatkin, 1948 (obligatory non-exclusive hematophagous); 2) nidicolous species Androlaelaps casalis Berlese, 1887 (obligatory non-exclusive hematophagous), Eulaelaps stabularis C. L. Koch, 1836, Haemogamasus nidiformnes Bregetova, 1955 (facultative hematophagous), Haemnogamnasus ambulans Thorell, 1872 (obligatory non-exclusive hematophagous), Hirstionyssus isabellinus Oudemans, 1913, and Hirstionyssus eusoricis Bregetova, 1956 (obligatory exclusive hematophagous). Last three species demonstrate the mixed type of parasitism. The population of gamasid mites on small mammals is most specific in tundra, southern forest-steppe and steppe; the fauna of gamasid mites in nests is most specific in southern forest-steppe and steppe.

  13. FEASIBILITY OF MICRONUCLEUS METHODS FOR MONITORING GENETIC DAMAGE IN TWO FERAL SPECIES OF SMALL MAMMALS

    EPA Science Inventory

    Peromyscus leucopus (white-footed mouse) and Cryptotis parva (least shrew) possess desirable attributes for biomonitoring contamination of terrestrial ecoystems, but few studies have examined the potential use of these species for monitoring exposure to genotoxic contaminants. Th...

  14. Tracking marine mammals and ships with small and large-aperture hydrophone arrays

    NASA Astrophysics Data System (ADS)

    Gassmann, Martin

    Techniques for passive acoustic tracking in all three spatial dimensions of marine mammals and ships were developed for long-term acoustic datasets recorded continuously over months using custom-designed arrays of underwater microphones (hydrophones) with spacing ranging from meters to kilometers. From the three-dimensional tracks, the acoustical properties of toothed whales and ships, such as sound intensity and directionality, were estimated as they are needed for the passive acoustic abundance estimation of toothed whales and for a quantitative description of the contribution of ships to the underwater soundscape. In addition, the tracks of the toothed whales reveal their underwater movements and demonstrate the potential of the developed tracking techniques to investigate their natural behavior and responses to sound generated by human activity, such as from ships or military SONAR. To track the periodically emitted echolocation sounds of toothed whales in an acoustically refractive environment in the upper ocean, a propagation-model based technique was developed for a hydrophone array consisting of one vertical and two L-shaped subarrays deployed from the floating instrument platform R/P FLIP. The technique is illustrated by tracking a group of five shallow-diving killer whales showing coordinated behavior. The challenge of tracking the highly directional echolocation sounds of deep-diving (< 1 km) toothed whales, in particular Cuvier's beaked whales, was addressed by embedding volumetric small-aperture (≈ 1 m element spacing) arrays into a large-aperture (≈ 1 km element spacing) seafloor array to reduce the minimum number of required receivers from five to two. The capabilities of this technique are illustrated by tracking several groups of up to three individuals over time periods from 10 min to 33 min within an area of 20 km2 in the Southern California Bight. To track and measure the underwater radiated sound of ships, a frequency domain beamformer was

  15. Living on the edge: roads and edge effects on small mammal populations.

    PubMed

    Fuentes-Montemayor, Elisa; Cuarón, Alfredo D; Vázquez-Domínguez, Ella; Benítez-Malvido, Julieta; Valenzuela-Galván, David; Andresen, Ellen

    2009-07-01

    insight into the effects that sharp road edges have on biological and social characteristics of small mammal populations, highlighting how such effects vary among species. Our findings have important conservation implications for these threatened species, but are also applicable in a broader context wherever there are abrupt edges caused by linear landscape features.

  16. A re-evaluation of the taphonomic methodology for the study of small mammal fossil assemblages of South America

    NASA Astrophysics Data System (ADS)

    Fernández, Fernando J.; Montalvo, Claudia I.; Fernández-Jalvo, Yolanda; Andrews, Peter; López, José Manuel

    2017-01-01

    The taphonomic methodology for the study of small mammal fossil was based mainly on actualistic studies of bones and teeth of insectivores (Soricidae, Talpidae, Erinaceidae) and rodents (Arvicolinae, Muridae) recovered from pellets of birds of prey and scats of carnivorous mammals from different places of North America, Europe and Africa. The digestive corrosion patterns on teeth of the South American rodents Sigmodontinae, Caviinae, Ctenomyidae and Abrocomidae, and the marsupials Monodelphini of central Argentina were observed. The comparison between the South American samples with the North American, African and European samples allowed us to establish similarities and differences in the digestive corrosion of the teeth. The main agreements have been recorded in the following groups: Arvicolinae with Caviinae and Abrocomidae; Murinae with Sigmodontinae; Soricidae, Talpidae and Erinaceidae with Monodelphini. However, the particular and simplified configuration of the molars of Ctenomyidae with thicker enamel and dentine exposed has promoted a new description of the categories of digestive corrosion. Likewise Muridae and Sigmodontinae molars, Ctenomyidae presents a delay in the appearance of signs of digestion with regard to other caviomorphs (Caviinae, Abrocomidae). This contribution may, therefore, be useful to know the origin of these South American faunas and the exact taphonomic agent that produced these assemblages. Finally, small mammal samples from an archaeo-palaeontological site from Northwestern Patagonia, Argentina, were studied in order to apply the new methodology emerged from the recent samples.

  17. Small-mammal data on early and middle Holocene climates and biotic communities in the Bonneville Basin, USA

    USGS Publications Warehouse

    Schmitt, D.N.; Madsen, D.B.; Lupo, K.D.

    2002-01-01

    Archaeological investigations in Camels Back Cave, western Utah, recovered a series of small-mammal bone assemblages from stratified deposits dating between ca. 12,000 and 500 14C yr B.P. The cave's early Holocene fauna includes a number of species adapted to montane or mesic habitats containing grasses and/or sagebrush (e.g., Lepus townsendii, Marmota flaviventris, Reithrodontomys megalotis, and Brachylagus idahoensis) which suggest that the region was relatively cool and moist until after 8800 14C yr B.P. Between ca. 8600 and 8100 14C yr B.P. these mammals became locally extinct, taxonomic diversity declined, and there was an increase in species well-adapted to xeric, low-elevation habitats, including ground squirrels, Lepus californicus and Neotoma lepida. The early small-mammal record from Camels Back Cave is similar to the 11,300-6000 14C yr B.P. mammalian sequence from Homestead Cave, northwestern Utah, and provides corroborative data on Bonneville Basin paleoenvironments and mammalian responses to middle Holocene desertification. ?? 2002 University of Washington.

  18. 50 CFR 18.27 - Regulations governing small takes of marine mammals incidental to specified activities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... anticipated impact of the activity upon the habitat of the marine mammal populations and the likelihood of restoration of the affected habitat; (v) The anticipated impact of the loss or modification of the habitat on... habitat and on the availability of the species for subsistence uses, paying particular attention...

  19. The pika and the watershed: The impact of small mammal poisoning on the ecohydrology of the Qinghai-Tibetan Plateau.

    PubMed

    Wilson, Maxwell C; Smith, Andrew T

    2015-02-01

    With approximately 20 % of the world's population living in its downstream watersheds, the Qinghai-Tibetan Plateau (QTP) is considered "Asia's Water Tower." However, grasslands of the QTP, where most of Asia's great rivers originate, are becoming increasingly degraded, which leads to elevated population densities of a native small mammal, the plateau pika (Ochotona curzoniae). As a result pikas have been characterized as a pest leading to wide-spread poisoning campaigns in an attempt to restore grassland quality. A contrary view is that pikas are a keystone species for biodiversity and that their burrowing activity provides a critical ecosystem service by increasing the infiltration rate of water, hence reducing overland flow. We demonstrate that poisoning plateau pikas significantly reduces infiltration rate of water across the QTP creating the potential for watershed-level impacts. Our results demonstrate the importance of burrowing mammals as ecosystem engineers, particularly with regard to their influence on hydrological functioning.

  20. Community- and landscape-level responses of reptiles and small mammals to feral-horse grazing in the Great Basin

    USGS Publications Warehouse

    Beever, Erik A.; Brussard, P.F.

    2004-01-01

    We investigated species- and community-level responses of squamate reptiles and granivorous small mammals to feral-horse grazing in two elevational strata across nine mountain ranges of the western Great Basin, USA. Although mammal species richness did not differ between horse-occupied and horse-removed sites, occupied sites possessed less community completeness (biotic integrity) and 1.1–7.4 times greater deer mice (Peromyscus maniculatus) than removed sites. In opposite fashion, horse-removed sites possessed greater reptile species richness and tended towards greater abundance for seven of nine species, yet unequal species pools across sites dictated that community completeness did not differ statistically between horse-removed and -occupied sites.

  1. Combining snowpack modeling and terrestrial laser scanner observations improves the simulation of small scale snow dynamics

    NASA Astrophysics Data System (ADS)

    Revuelto, Jesús; Vionnet, Vincent; López-Moreno, Juan-Ignacio; Lafaysse, Matthieu; Morin, Samuel

    2016-02-01

    Accurately determining the snowpack distribution in mountain areas is complex because of the difficulty of establishing over large areas the spatial distribution of all variables that define the state of the snowpack at any particular time. In this study we used distributed snowpack simulations that were corrected throughout the snow season using snow depth distributions measured using a terrestrial laser scanner (TLS). This enabled us to obtain a more realistic view of the small scale spatial evolution of the mass and depth of the snowpack. Several TLS snow depth data acquisitions were made during the 2012, 2013 and 2014 snow seasons in a small catchment (55 ha) located in the central Spanish Pyrenees. The Crocus snowpack model was used to simulate the snowpack evolution on a 5-m grid, based on downscaled meteorological variables obtained using SAFRAN reanalysis. The simulation was stopped when a snow depth distribution map measured using the TLS was available, and the modeled snow depth distribution was adjusted to match the observed snow depth. The snow simulation was then restarted and run until the next TLS acquisition was available. Prior to matching the simulation and observational data, both snowpack distributions were compared. The results for the three snow seasons showed an improvement in the snowpack simulation, especially with respect to simulating the influence of small scale topographic effects on the observed snowpack distribution, and also the timing of snow melt dynamics.

  2. The transfer of (137)Cs, Pu isotopes and (90)Sr to bird, bat and ground-dwelling small mammal species within the Chernobyl exclusion zone.

    PubMed

    Beresford, N A; Gaschak, S; Maksimenko, Andrey; Wood, M D

    2016-03-01

    Protected species are the focus of many radiological environmental assessments. However, the lack of radioecological data for many protected species presents a significant international challenge. Furthermore, there are legislative restrictions on destructive sampling of protected species to obtain such data. Where data are not available, extrapolations are often made from 'similar' species but there has been little attempt to validate this approach. In this paper we present what, to our knowledge, is the first study purposefully designed to test the hypothesis that radioecological data for unprotected species can be used to estimate conservative radioecolgical parameters for protected species; conservatism being necessary to ensure that there is no significant impact. The study was conducted in the Chernobyl Exclusion Zone. Consequently, we are able to present data for Pu isotopes in terrestrial wildlife. There has been limited research on Pu transfer to terrestrial wildlife which contrasts with the need to assess radiation exposure of wildlife to Pu isotopes around many nuclear facilities internationally. Our results provide overall support for the hypothesis that data for unprotected species can be used to adequately assess the impacts for ionising radiation on protected species. This is demonstrated for a range of mammalian and avian species. However, we identify one case, the shrew, for which data from other ground-dwelling small mammals would not lead to an appropriately conservative assessment of radiation impact. This indicates the need to further test our hypothesis across a range of species and ecosystems, and/or ensure adequate conservatism within assessments. The data presented are of value to those trying to more accurately estimate the radiation dose to wildlife in the Chernobyl Exclusion Zone, helping to reduce the considerable uncertainty in studies reporting dose-effect relationships for wildlife. A video abstract for this paper is available from

  3. Metabolic profile of the perivertebral muscles in small therian mammals: implications for the evolution of the mammalian trunk musculature.

    PubMed

    Schilling, Nadja

    2009-01-01

    In order to gain a better understanding of the ancestral properties of the perivertebral muscles of mammals, this study investigated the fiber type composition of these muscles in six small, extant therians (two metatherians and four eutherians) similar in body shape to early mammals. Despite a few species-specific differences, the investigated species were very similar in their overall distribution of fiber types indicating similar functional demands on the back muscles in mammals of this body size and shape. Deep and short, mono- or multisegmental muscles (i.e., mm. interspinales, intermammillares, rotatores et intertransversarii) consistently showed the highest percentage of slow, oxidative fibers implying a function as local stabilizers of the vertebral column. Superficial and large, polysegmental muscles (i.e., mm. multifidus, sacrospinalis, iliopsoas et psoas minor) were predominantly composed of fast, glycolytic fibers suggesting they function to both globally stabilize and mobilize the spine during rapid non-locomotor and locomotor activities. Some muscles contained striking accumulations of oxidative fibers in specific regions (mm. longissimus et quadratus lumborum). These regions are hypothesized to function independently from the rest of the muscle belly and may be comparable in their functionality to regionalized limb muscles. The deep, central oxidative region in the m. longissimus lumborum appears to be a general feature of mammals and likely serves a proprioceptive function to control the postural equilibrium of the pelvic girdle and lumbar spine. The potential functions of the m. quadratus lumborum during ventilation and ventral stabilization of the vertebral column are discussed. Because representatives of the stem lineage of mammals were comparable in their body proportions and probably also locomotor parameters to the species investigated here, I suggest that the described fiber type distribution is representative of the ancestral condition in

  4. Evaluation of Wavelet Denoising Methods for Small-Scale Joint Roughness Estimation Using Terrestrial Laser Scanning

    NASA Astrophysics Data System (ADS)

    Bitenc, M.; Kieffer, D. S.; Khoshelham, K.

    2015-08-01

    The precision of Terrestrial Laser Scanning (TLS) data depends mainly on the inherent random range error, which hinders extraction of small details from TLS measurements. New post processing algorithms have been developed that reduce or eliminate the noise and therefore enable modelling details at a smaller scale than one would traditionally expect. The aim of this research is to find the optimum denoising method such that the corrected TLS data provides a reliable estimation of small-scale rock joint roughness. Two wavelet-based denoising methods are considered, namely Discrete Wavelet Transform (DWT) and Stationary Wavelet Transform (SWT), in combination with different thresholding procedures. The question is, which technique provides a more accurate roughness estimates considering (i) wavelet transform (SWT or DWT), (ii) thresholding method (fixed-form or penalised low) and (iii) thresholding mode (soft or hard). The performance of denoising methods is tested by two analyses, namely method noise and method sensitivity to noise. The reference data are precise Advanced TOpometric Sensor (ATOS) measurements obtained on 20 × 30 cm rock joint sample, which are for the second analysis corrupted by different levels of noise. With such a controlled noise level experiments it is possible to evaluate the methods' performance for different amounts of noise, which might be present in TLS data. Qualitative visual checks of denoised surfaces and quantitative parameters such as grid height and roughness are considered in a comparative analysis of denoising methods. Results indicate that the preferred method for realistic roughness estimation is DWT with penalised low hard thresholding.

  5. Woodland recovery after suppression of deer: cascade effects for small mammals, wood mice (Apodemus sylvaticus) and bank voles (Myodes glareolus).

    PubMed

    Bush, Emma R; Buesching, Christina D; Slade, Eleanor M; Macdonald, David W

    2012-01-01

    Over the past century, increases in both density and distribution of deer species in the Northern Hemisphere have resulted in major changes in ground flora and undergrowth vegetation of woodland habitats, and consequentially the animal communities that inhabit them. In this study, we tested whether recovery in the vegetative habitat of a woodland due to effective deer management (from a peak of 0.4-1.5 to <0.17 deer per ha) had translated to the small mammal community as an example of a higher order cascade effect. We compared deer-free exclosures with neighboring open woodland using capture-mark-recapture (CMR) methods to see if the significant difference in bank vole (Myodes glareolus) and wood mouse (Apodemus sylvaticus) numbers between these environments from 2001-2003 persisted in 2010. Using the multi-state Robust Design method in program MARK we found survival and abundance of both voles and mice to be equivalent between the open woodland and the experimental exclosures with no differences in various metrics of population structure (age structure, sex composition, reproductive activity) and individual fitness (weight), although the vole population showed variation both locally and temporally. This suggests that the vegetative habitat--having passed some threshold of complexity due to lowered deer density--has allowed recovery of the small mammal community, although patch dynamics associated with vegetation complexity still remain. We conclude that the response of small mammal communities to environmental disturbance such as intense browsing pressure can be rapidly reversed once the disturbing agent has been removed and the vegetative habitat is allowed to increase in density and complexity, although we encourage caution, as a source/sink dynamic may emerge between old growth patches and the recently disturbed habitat under harsh conditions.

  6. Small mammal use of native warm-season and non-native cool-season grass forage fields

    USGS Publications Warehouse

    Ryan L Klimstra,; Christopher E Moorman,; Converse, Sarah J.; Royle, J. Andrew; Craig A Harper,

    2015-01-01

    Recent emphasis has been put on establishing native warm-season grasses for forage production because it is thought native warm-season grasses provide higher quality wildlife habitat than do non-native cool-season grasses. However, it is not clear whether native warm-season grass fields provide better resources for small mammals than currently are available in non-native cool-season grass forage production fields. We developed a hierarchical spatially explicit capture-recapture model to compare abundance of hispid cotton rats (Sigmodon hispidus), white-footed mice (Peromyscus leucopus), and house mice (Mus musculus) among 4 hayed non-native cool-season grass fields, 4 hayed native warm-season grass fields, and 4 native warm-season grass-forb ("wildlife") fields managed for wildlife during 2 summer trapping periods in 2009 and 2010 of the western piedmont of North Carolina, USA. Cotton rat abundance estimates were greater in wildlife fields than in native warm-season grass and non-native cool-season grass fields and greater in native warm-season grass fields than in non-native cool-season grass fields. Abundances of white-footed mouse and house mouse populations were lower in wildlife fields than in native warm-season grass and non-native cool-season grass fields, but the abundances were not different between the native warm-season grass and non-native cool-season grass fields. Lack of cover following haying in non-native cool-season grass and native warm-season grass fields likely was the key factor limiting small mammal abundance, especially cotton rats, in forage fields. Retention of vegetation structure in managed forage production systems, either by alternately resting cool-season and warm-season grass forage fields or by leaving unharvested field borders, should provide refugia for small mammals during haying events.

  7. Woodland Recovery after Suppression of Deer: Cascade effects for Small Mammals, Wood Mice (Apodemus sylvaticus) and Bank Voles (Myodes glareolus)

    PubMed Central

    Bush, Emma R.; Buesching, Christina D.; Slade, Eleanor M.; Macdonald, David W.

    2012-01-01

    Over the past century, increases in both density and distribution of deer species in the Northern Hemisphere have resulted in major changes in ground flora and undergrowth vegetation of woodland habitats, and consequentially the animal communities that inhabit them. In this study, we tested whether recovery in the vegetative habitat of a woodland due to effective deer management (from a peak of 0.4–1.5 to <0.17 deer per ha) had translated to the small mammal community as an example of a higher order cascade effect. We compared deer-free exclosures with neighboring open woodland using capture-mark-recapture (CMR) methods to see if the significant difference in bank vole (Myodes glareolus) and wood mouse (Apodemus sylvaticus) numbers between these environments from 2001–2003 persisted in 2010. Using the multi-state Robust Design method in program MARK we found survival and abundance of both voles and mice to be equivalent between the open woodland and the experimental exclosures with no differences in various metrics of population structure (age structure, sex composition, reproductive activity) and individual fitness (weight), although the vole population showed variation both locally and temporally. This suggests that the vegetative habitat - having passed some threshold of complexity due to lowered deer density - has allowed recovery of the small mammal community, although patch dynamics associated with vegetation complexity still remain. We conclude that the response of small mammal communities to environmental disturbance such as intense browsing pressure can be rapidly reversed once the disturbing agent has been removed and the vegetative habitat is allowed to increase in density and complexity, although we encourage caution, as a source/sink dynamic may emerge between old growth patches and the recently disturbed habitat under harsh conditions. PMID:22347472

  8. Strong evidence for terrestrial support of zooplankton in small lakes based on stable isotopes of carbon, nitrogen, and hydrogen

    PubMed Central

    Cole, Jonathan J.; Carpenter, Stephen R.; Kitchell, Jim; Pace, Michael L.; Solomon, Christopher T.; Weidel, Brian

    2011-01-01

    Cross-ecosystem subsidies to food webs can alter metabolic balances in the receiving (subsidized) system and free the food web, or particular consumers, from the energetic constraints of local primary production. Although cross-ecosystem subsidies between terrestrial and aquatic systems have been well recognized for benthic organisms in streams, rivers, and the littoral zones of lakes, terrestrial subsidies to pelagic consumers are more difficult to demonstrate and remain controversial. Here, we adopt a unique approach by using stable isotopes of H, C, and N to estimate terrestrial support to zooplankton in two contrasting lakes. Zooplankton (Holopedium, Daphnia, and Leptodiaptomus) are comprised of ≈20–40% of organic material of terrestrial origin. These estimates are as high as, or higher than, prior measures obtained by experimentally manipulating the inorganic 13C content of these lakes to augment the small, natural contrast in 13C between terrestrial and algal photosynthesis. Our study gives credence to a growing literature, which we review here, suggesting that significant terrestrial support of pelagic crustaceans (zooplankton) is widespread. PMID:21245299

  9. Strong evidence for terrestrial support of zooplankton in small lakes based on stable isotopes of carbon, nitrogen, and hydrogen

    USGS Publications Warehouse

    Cole, J.J.; Carpenter, S.R.; Kitchell, J.; Pace, M.L.; Solomon, C.T.; Weidel, B.

    2011-01-01

    Cross-ecosystem subsidies to food webs can alter metabolic balances in the receiving (subsidized) system and free the food web, or particular consumers, from the energetic constraints of local primary production. Although cross-ecosystem subsidies between terrestrial and aquatic systems have been well recognized for benthic organisms in streams, rivers, and the littoral zones of lakes, terrestrial subsidies to pelagic consumers are more difficult to demonstrate and remain controversial. Here, we adopt a unique approach by using stable isotopes of H, C, and N to estimate terrestrial support to zooplankton in two contrasting lakes. Zooplankton (Holopedium, Daphnia, and Leptodiaptomus) are comprised of ???20-40% of organic material of terrestrial origin. These estimates are as high as, or higher than, prior measures obtained by experimentally manipulating the inorganic 13C content of these lakes to augment the small, natural contrast in 13C between terrestrial and algal photosynthesis. Our study gives credence to a growing literature, which we review here, suggesting that significant terrestrial support of pelagic crustaceans (zooplankton) is widespread.

  10. Landscape structure in a managed forest mosaic of the Southern Appalachian Mountains and its influence on songbirds and small mammals

    NASA Astrophysics Data System (ADS)

    Leimgruber, Peter

    Forests in the Appalachian Mountains have been severely affected by logging in the past and little old-growth is left. The remaining forests form a heterogeneous mosaic of different forest successions. A concern for conservation is how additional logging will alter the mosaic and its fauna. I studied the effects of logging on the landscape mosaic and how changes in the landscape structure influence small mammals and birds in the George Washington National Forest, Virginia. My dissertation also included research on how to improve techniques for landscape ecological studies, such as roadside monitoring of birds and mapping of forest resources using remote sensing and Geographic Information Systems (GIS). Because of the scale dependency of landscape-ecological relationships, I investigated how landscape structure in the forest mosaic changes with increasing scales. I determined threshold scales at which structure changed markedly. After establishing a baseline, I examined how logging affected the intensity and location of such thresholds. I found thresholds in landscape structure exist at 400-, 500-, and 800-m intervals from the outer edge of the cut. While logging did not change threshold location and intensity for global landscape indices, such as dominance and contagion, thresholds for focal indices, such as mean patch size and percent cover for early-successional forest, changed markedly. Using GIS, I determined how logging affected small mammals and birds at the landscape scale. I divided the landscape into three zones (zone 1, inside logged areas; zone 2, 20--400 m from logged areas; zone 3, 1000--1500 m from logged areas). Logging changed species presence and richness more drastically in close proximity of cuts than on the landscape and influenced birds more strongly than mammals. In the cuts, edge-adapted birds, such as the indigo bunting (Passerina cyanea), replaced forest interior species, such as the Acadian flycatcher (Empidonax virescens). Most

  11. A unique resource mutualism between the giant Bornean pitcher plant, Nepenthes rajah, and members of a small mammal community.

    PubMed

    Greenwood, Melinda; Clarke, Charles; Lee, Ch'ien C; Gunsalam, Ansou; Clarke, Rohan H

    2011-01-01

    The carnivorous pitcher plant genus Nepenthes grows in nutrient-deficient substrates and produce jug-shaped leaf organs (pitchers) that trap arthropods as a source of N and P. A number of Bornean Nepenthes demonstrate novel nutrient acquisition strategies. Notably, three giant montane species are engaged in a mutualistic association with the mountain treeshrew, Tupaia montana, in which the treeshrew defecates into the pitchers while visiting them to feed on nectar secretions on the pitchers' lids.Although the basis of this resource mutualism has been elucidated, many aspects are yet to be investigated. We sought to provide insights into the value of the mutualism to each participant. During initial observations we discovered that the summit rat, R. baluensis, also feeds on sugary exudates of N. rajah pitchers and defecates into them, and that this behavior appears to be habitual. The scope of the study was therefore expanded to assess to what degree N. rajah interacts with the small mammal community.We found that both T. montana and R. baluensis are engaged in a mutualistic interaction with N. rajah. T .montana visit pitchers more frequently than R. baluensis, but daily scat deposition rates within pitchers do not differ, suggesting that the mutualistic relationships are of a similar strength. This study is the first to demonstrate that a mutualism exists between a carnivorous plant species and multiple members of a small mammal community. Further, the newly discovered mutualism between R. baluensis and N. rajah represents only the second ever example of a multidirectional resource-based mutualism between a mammal and a carnivorous plant.

  12. Posture Does Not Matter! Paw Usage and Grasping Paw Preference in a Small-Bodied Rooting Quadrupedal Mammal

    PubMed Central

    Joly, Marine; Scheumann, Marina; Zimmermann, Elke

    2012-01-01

    Background Recent results in birds, marsupials, rodents and nonhuman primates suggest that phylogeny and ecological factors such as body size, diet and postural habit of a species influence limb usage and the direction and strength of limb laterality. To examine to which extent these findings can be generalised to small-bodied rooting quadrupedal mammals, we studied trees shrews (Tupaia belangeri). Methodology/Principal Findings We established a behavioural test battery for examining paw usage comparable to small-bodied primates and tested 36 Tupaia belangeri. We studied paw usage in a natural foraging situation (simple food grasping task) and measured the influence of varying postural demands (triped, biped, cling, sit) on paw preferences by applying a forced-food grasping task similar to other small-bodied primates. Our findings suggest that rooting tree shrews prefer mouth over paw usage to catch food in a natural foraging situation. Moreover, we demonstrated that despite differences in postural demand, tree shrews show a strong and consistent individual paw preference for grasping across different tasks, but no paw preference at a population level. Conclusions/Significance Tree shrews showed less paw usage than small-bodied quadrupedal and arboreal primates, but the same paw preference. Our results confirm that individual paw preferences remain constant irrespective of postural demand in some small-bodied quadrupedal non primate and primate mammals which do not require fine motoric control for manipulating food items. Our findings suggest that the lack of paw/hand preference for grasping food at a population level is a universal pattern among those species and that the influence of postural demand on manual lateralisation in quadrupeds may have evolved in large-bodied species specialised in fine manipulations of food items. PMID:22666494

  13. Do species populations really start small? New perspectives from the Late Neogene fossil record of African mammals.

    PubMed Central

    Vrba, E S; DeGusta, D

    2004-01-01

    This analysis of all known African larger mammals of the past 10 Myr offers new perspectives on the geographical circumstances of speciation. Our central question is: does the fossil evidence support the idea that most new species start as small populations and, if true, how long is the average growth interval until species are established at their mean later size? This simple question is important to unravelling the competing claims of rival models of speciation. We approached it by direct use of fossil data, which, to our knowledge, has not been done previously. We compared the numbers of fossil site records, as a proxy for magnitude of geographical spread, between survivorship intervals across all species. The results show that the average mammal species has indeed started its life in a relatively small population, and thereafter increased rapidly in geographical spread to reach its long-term equilibrium abundance by about 1 million years after origin. Some theoretical implications of these results are discussed. PMID:15101584

  14. Responses of a small-mammal community to habitat management through controlled burning in a protected Mediterranean area

    NASA Astrophysics Data System (ADS)

    Moreno, Sacramento; Rouco, Carlos

    2013-05-01

    Fire is widely used as a management tool to achieve conservation goals. However, the consequences of such management on non-target species are frequently neglected and unknown. This study examines the effects of traditional management practices of scrubland clearance by controlled burning to improve menaced carnivores on non-target species: rodent and insectivores in Doñana National Park (SW of Iberian Peninsula). We used capture-recapture methods to examine changes in abundance in areas that were burnt one and three years ago, compared with unburnt areas. Results showed that burnt areas had higher species abundances, but mainly on the ecotonal boundaries. Species abundances showed dramatic seasonal differences with high abundances in autumn and winter, and very low abundance in summer. Our study revealed that scrubland management by controlled fires increases the abundance of small mammal species, mainly Mus spretus and Apodemus sylvaticus. We found only four small mammal species between the different treatments. However, some species that were formerly abundant in Doñana, such as Elyomis quercinus, were found only in burnt areas. Our results suggest that controlled burning is not contributing to the current loss of biotic diversity in this community.

  15. Comparative evaluation of several small mammal species as monitors of heavy metals, radionuclides, and selected organic compounds in the environment

    SciTech Connect

    Talmage, S.S.

    1989-01-01

    The merit of using small mammals monitors of environmental contaminants was assessed using data from the literature and results of a monitoring study at selected sites on the Oak Ridge National Laboratory reservation. In the field, ten species of small mammals were trapped at contaminated and reference sites to monitor for exposure to mercury, strontium-90, and benzo(a)pyrene. Residue analyses and a hemoglobin-adduct assay were performed on the animals. Accumulation of mercury in kidney tissue and strontium-90 in bone was related to the degree of contamination of the environment as well as trophic level of the species. Both shorttail shrews and white-footed mice trapped at the mercury-contaminated site had significantly higher concentrations of mercury in kidney tissue than those trapped at the control site, with the insectivorous shrew having a higher concentration than the omnivorous mouse. Strontium-90 was present in the bone of all species trapped at the radionuclide-contaminated sites, but was highest in the eastern harvest mouse. The hemoglobin-adduct assay was evaluated as an indicator of subchronic exposure to benzo(a)pyrene in the laboratory and chronic exposure in the field.

  16. Fleas associated with non-flying small mammal communities from northern and central Chile: with new host and locality records.

    PubMed

    Bazán-León, E A; Lareschi, M; Sanchez, J; Soto-Nilo, G; Lazzoni, I; Venegas, C I; Poblete, Y; Vásquez, R A

    2013-12-01

    Fleas associated with small mammals from seven localities from northern and central Chile were assessed. We captured 352 small mammals belonging to 12 species from which we obtained 675 fleas belonging to 15 different species. The most frequently captured flea species were Neotyphloceras crassispina crassispina (n = 198) and N. chilensis (n = 175). High values of flea species richness and diversity were found in Fray Jorge National Park (NP), a north-central Chilean site, whereas the highest values of mean abundance (MA) and prevalence were found in three diverse sites that include Los Molles River, a high altitude site located in north-central Chile, Fray Jorge NP and Dichato, in south-central Chile. On the other hand, high values of flea richness and diversity were found on two rodent species, Abrothrix olivacea and A. longipilis, whereas the highest values of MA and prevalence were found on Oligoryzomys longicaudatus, A. longipilis and Phyllotis xanthopygus. A total of three new host recordings, nine new localities and nine new host species and locality recordings are reported. Also, this study represents the first known record of Tetrapsyllus (Tetrapsyllus) comis in Chile and the first ecological analysis of Neotyphloceras chilensis.

  17. Predictors for presence and abundance of small mammals in households of villages endemic for commensal rodent plague in Yunnan Province, China

    PubMed Central

    Yin, Jia-Xiang; Geater, Alan; Chongsuvivatwong, Virasakdi; Dong, Xing-Qi; Du, Chun-Hong; Zhong, You-Hong; McNeil, Edward

    2008-01-01

    Background Ninety-one rodent plague epidemics have occurred in Lianghe county, Yunnan Province, China, between 1990 and 2006. This study aimed to identify predictors for the presence and abundance of small mammals in households of villages endemic for rodent plague in Lianghe county. Results Rattus flavipectus and Suncus murinus were the two species captured in 110 households. Keeping cats decreased the number of captures of R. flavipectus by one to two thirds and the chance of reported small mammal sightings in houses by 60 to 80%. Food availability was associated with fewer captures. Keeping food in sacks decreased the small mammal captures, especially of S. murinus 4- to 8-fold. Vegetables grown around house and maize grown in the village reduced the captures of S. murinus and R. flavipectus by 73 and 45%, respectively. An outside toilet and garbage piles near the house each reduced R. flavipectus captures by 39 and 37%, respectively, while raising dogs and the presence of communal latrines in the village increased R. flavipectus captures by 76 and 110% but were without detectable effect on small mammal sightings. Location adjacent to other houses increased captures 2-fold but reduced the chance of sightings to about half. In addition, raising ducks increased the chance of sighting small mammals 2.7-fold. Even after adjusting for these variables, households of the Dai had higher captures than those of the Han and other ethnic groups. Conclusion Both species captures were reduced by availability of species-specific foods in the environment, whereas other predictors for capture of the two species differed. Other than the beneficial effect of cats, there were also discrepancies between the effects on small mammal captures and those on sightings. These differences should be considered during the implementation and interpretation of small mammal surveys. PMID:19068139

  18. Anthropogenic soils and land use patterns in relation to small mammal and flea abundance in plague endemic area of Western Usambara Mountains, Tanzania.

    PubMed

    Kimaro, Didas N; Msanya, Balthazar M; Meliyo, Joel; Hieronimo, Proches; Mwango, Sibaway; Kihupi, Nganga I; Gulinck, Hubert; Deckers, Jozef A

    2014-07-01

    Heterogeneity in the landscapes of West Usambara Mountains on land use and human activities has been reported. However, the interface of land use patterns and human modified soils with small mammal and flea abundance for possible explanation of plague has not been explored. This study was carried out to determine the link between anthropogenic soils and land use patterns on small mammal and flea abundance and the occurrence of reported plague in the Western Usambara Mountains in Tanzania. Standard soil survey methods were used to identify and describe soils and land use patterns on lower slopes and valley bottoms on which the surrounding villages are reported to have high and medium plague frequencies. The identified soils were characterised in terms of their morphological and physico-chemical properties and classified according to FAO-World Reference Base for Soil Resources. Small mammals were trapped on the same landscape positions and identified to genus/species level. Fleas were removed from the trapped small mammals, counted and identified to species level. In total 57 small mammals were captured from which 32 fleas were collected. Results show that human settlements and mixed cultivation on lower slopes and continuous vegetable cropping in the valley bottoms are dominant land use types. Intensive use of forest soils, manuring and irrigation on farms in the studied landscapes have contributed to the development of uniquely human modified soils namely Hortic Anthrosols in the lower slopes and Plaggic Irragric Hortic Anthrosols in valley bottoms. The identified anthropogenic soils and land use patterns are associated with high abundance of small mammals (Mastomys natalensis) and flea species (Xenopsylla brasiliensis and Dinopsyllus lypusus). This phenomenon is vividly apparent in the villages with medium to high plague frequencies. The study suggests that plague surveillance programmes should consider the existing relationship between anthropogenic soils, land

  19. Photographic identification of individuals of a free-ranging, small terrestrial vertebrate.

    PubMed

    Treilibs, Claire E; Pavey, Chris R; Hutchinson, Mark N; Bull, C Michael

    2016-02-01

    Recognition of individuals within an animal population is central to a range of estimates about population structure and dynamics. However, traditional methods of distinguishing individuals, by some form of physical marking, often rely on capture and handling which may affect aspects of normal behavior. Photographic identification has been used as a less-invasive alternative, but limitations in both manual and computer-automated recognition of individuals are particularly problematic for smaller taxa (<500 g). In this study, we explored the use of photographic identification for individuals of a free-ranging, small terrestrial reptile using (a) independent observers, and (b) automated matching with the Interactive Individual Identification System (I(3)S Pattern) computer algorithm. We tested the technique on individuals of an Australian skink in the Egernia group, Slater's skink Liopholis slateri, whose natural history and varied scale markings make it a potentially suitable candidate for photo-identification. From 'photographic captures' of skink head profiles, we designed a multi-choice key based on alternate character states and tested the abilities of observers - with or without experience in wildlife survey - to identify individuals using categorized test photos. We also used the I(3)S Pattern algorithm to match the same set of test photos against a database of 30 individuals. Experienced observers identified a significantly higher proportion of photos correctly (74%) than those with no experience (63%) while the I(3)S software correctly matched 67% as the first ranked match and 83% of images in the top five ranks. This study is one of the first to investigate photo identification with a free-ranging small vertebrate. The method demonstrated here has the potential to be applied to the developing field of camera-traps for wildlife survey and thus a wide range of survey and monitoring applications.

  20. Small-mammal populations of a Maryland woodlot, 1949-1954

    USGS Publications Warehouse

    Stickel, L.F.; Warbach, O.

    1960-01-01

    SUMMARY: Small-mammal populations of a 4.4-acre farm woodlot on the Patuxent Research Center, Mary land were studied by periodic live trapping for nearly 5 years, I949-54: The woodlot is a mixed stand of pine and deciduous trees, most of which began to grow in an abandoned farm field in the decade 1914-24. Traps were set in a 60-foot grid at intervals of approximately 2 months. Peromyscus leucopus, Microtus pennsylvanicus, and Pitymys pinetorum were the principal species. Peromyscus were most numerous. They fluctuated seasonally from a high in December to a low in April. Numbers increased to a low midsummer peak, declined slightly, then increased again to the high for the year in December. Seasonal trends in the numbers were intermediate between seasonal cycles in the north and those in the south. They were similar to the pattern in Michigan, although population peaks in fall were about a month later in Maryland. Our December populations varied from 3.9 to 8.6 Peromyscus per acre, April populations from 0 to 3.6 per acre. High numbers were present through most of 1951 and 1953. One Peromyscus was trapped in the woodlot for a period of 38 months, and several others for a year or more. The average expectancy of residence was about 3 months. No seasonal differences in persistence in the woodlot were noted. Most Peromyscus maintained home ranges in the same. general area from month to month. A few made trips away from their usual ranges, or gradually shifted their ranges. Several mice ranged over the entire woodlot at some times, but occupied more limited parts of it at other times. The history of the travels of a mouse that lived there 38 mouths is discussed in detail. The greatest distance between capture sites was taken as an indication of range size. Distances, measured for mice trapped 14 or more times apiece, averaged 280 feet for females, 378 feet for males. These were long-term records and so included any shifts of range or trips that occurred. True home ranges

  1. Natural history of tick-borne spotted fever in the USA. Susceptibility of small mammals to virulent Rickettsia rickettsii.

    PubMed

    Burgdorfer, W; Friedhoff, K T; Lancaster, J L

    1966-01-01

    In the ecology of spotted fever rickettsiae, one of the as yet unsolved problems concerns the significance of small animals in the distribution of Rickettsia rickettsii in nature. In the Bitter Root Valley of western Montana, a great variety of rodents, rabbits and hares are known to serve as the preferred hosts for the immature stages of the vector tick, Dermacentor andersoni.The authors analyse the susceptibility of various species of small mammals to virulent R. rickettsii and evaluate their efficiency as sources of infection for larval ticks. The results demonstrate that meadow-mice, Columbian ground-squirrels, golden-mantled ground-squirrels, chipmunks and snowshoe hares (the latter to a lesser extent), when bitten by infected ticks, respond with rickettsiaemias of sufficient length and degree to infect normal larval D. andersoni. High infection rates were obtained in ticks that fed during periods of high rickettsial concentrations in the blood.

  2. Long-term data set of small mammals from owl pellets in the Atlantic-Mediterranean transition area

    PubMed Central

    Escribano, Nora; Galicia, David; Ariño, Arturo H.; Escala, Carmen

    2016-01-01

    We describe the pellet sampling data set from the Vertebrate Collection of the Museum of Zoology of the University of Navarra. This data set compiles all information about small mammals obtained from the analysis of owl pellets. The collection consists on skulls, mandibles, and some skeletons of 36 species of more than 72,000 georeferenced specimens. These specimens come from the Iberian Peninsula although most samples were collected in Navarra, a highly diverse transitional area of 10,000 kilometre square sitting across three biogeographical regions. The collection spans more than forty years and is still growing as a result of the establishment of a barn owl pellet monitoring network in 2015. The program will provide critical information about the evolution of the small mammals’ community in this transition zone as it changes over time. PMID:27676217

  3. Juvenile frogs compensate for small metamorph size with terrestrial growth: Overcoming the effects of larval density and insecticide exposure

    USGS Publications Warehouse

    Boone, M.D.

    2005-01-01

    I reared four species of anurans (Rana sphenocephala [Southern Leopard Frog], Rana blairi [Plains Leopard Frog], Rana clamitans [Green Frog], and Bufo woodhousii [Woodhouse's Toad]) for seven to 12 months in small, outdoor terrestrial enclosures (1 x 2 m) to examine the consequences of larval competition (via density) and contaminant exposure (via the insecticide carbaryl). I added six Rana clamitans, eight Rana sphenocephala, eight Rana blairi, and 10 Bufo woodhousii to terrestrial enclosures shortly after metamorphosis and recaptured them during the following spring. All anurans from low-density ponds were significantly larger than those from high-density ponds, but these size differences did not significantly affect survival to or size at spring emergence. However, R. sphenocephala, R. blairi, and R. clamitans that survived to spring had been larger at metamorphosis on average than those that did not survive; in contrast, B. woodhousii that survived the winter were smaller at metamorphosis on average than those that did not survive. Carbaryl exposure affected mass at metamorphosis of R. clamitans and B. woodhousii that were added to enclosures, but this difference disappeared or did not increase by spring emergence. Overall, exposure to carbaryl during the larval period did not have any apparent effects on survival or growth during the terrestrial phase. In my study, anurans were able to offset small size at metamorphosis with terrestrial growth, although there was a trend of reduced overwinter survival for ranid species that metamorphosed at a smaller size. Copyright 2005 Society for the Study of Amphibians and Reptiles.

  4. Response to enrichment, type and timing: small mammals vary in their response to a springtime cicada but not a carbohydrate pulse.

    PubMed

    Vandegrift, Kurt J; Hudson, Peter J

    2009-01-01

    1. Masting events in the autumn provide a carbohydrate-rich pulse of resources that can influence the dynamics of small mammals and their natural enemies. Similar patterns are observed with the periodical cicada emergence which provides a protein-rich pulse in the spring, but comparisons are confounded by timing and food type. 2. We compared the influence of a naturally occurring spring pulse of cicadas with an experimental spring pulse of carbohydrate-rich seeds. We used a replicated population level field experiment and capture-mark-recapture techniques to record the vital rates, demographics, and abundance of Peromyscus leucopus (the white-footed mouse), as well as other small mammals and their parasites. 3. The density of P. leucopus on grids where cicadas emerged was 55% higher than controls as a consequence of early breeding. This was followed by an increase in the prevalence of the nematode Pterygodermatities peromysci, reduced breeding and decreased recruitment rates. Other small mammals including Tamias striatus (eastern chipmunk) and Blarina brevicauda (short-tailed shrew), increased in density, but there was no affect on Sorex cinereus (masked shrew). 4. In contrast to the presence of cicadas, there was no influence of sunflower seed supplementation on small mammal density, vital rates, or reproduction with the exception of an increase in B. brevicauda density. The response of small mammals to seasonal pulses depends on timing, food type, and species.

  5. Evaluation of the joint effect of glyphosate and dimethoate using a small-scale terrestrial ecosystem.

    PubMed

    Santos, Miguel J G; Morgado, Rui; Ferreira, Nuno Gonçalo C; Soares, Amadeu M V M; Loureiro, Susana

    2011-10-01

    In the present work a small-scale terrestrial ecosystem (STEM) containing a soil collected from an agricultural field in Central Portugal was used to evaluate the effects of the combination of the herbicide glyphosate and the insecticide dimethoate. Earthworms (Eisenia andrei), isopods (Porcellionides pruinosus), turnip seeds (Brassica rapa), and bait-lamina strips were placed in the STEM. The results showed that the application of the recommended field dose of both pesticides did not cause any effect on the weight variation of earthworms and growth of the plants. The application of the herbicide, even at 5 and 10 times the field dose, increased feeding activity in soil (bait-lamina test), although the application of dimethoate led to a decrease in feeding activity in all concentrations tested. The binary mixtures performed showed that according to the Independent Action model, synergism (higher effect than expected from the single exposures) was observed in both the shoot length and fresh weight of B. rapa at 5 times the field dose, but antagonism was observed at 10 times the field dose. Regarding the germination success, synergism was observed at the field dose, but antagonism was detected at 5 times and 10 times the field dose. There was a decrease on the earthworm's weight in all concentrations tested, although no statistical differences were observed in any of the treatments made. Regarding depth distribution of E. andrei, worms were found in the upper layer more than it was predicted for all concentrations. In the mixtures with the field and 5 times the field dose there was a decrease in the feeding activity (bait-lamina consumption) by the soil fauna. From the four biomarkers assessed on the isopods (Catalase, Acetylcholinesterase, Glutathione-S-transferase, and Lipid peroxidation), only a significant decrease in the Acetylcholinesterase activity upon dimethoate and the binary mixtures exposures performed with the field dose was observed and on Lipid

  6. Characteristics and Propagation of Airgun Pulses in Shallow Water with Implications for Effects on Small Marine Mammals

    PubMed Central

    Hermannsen, Line; Tougaard, Jakob; Beedholm, Kristian; Nabe-Nielsen, Jacob; Madsen, Peter Teglberg

    2015-01-01

    Airguns used in seismic surveys are among the most prevalent and powerful anthropogenic noise sources in marine habitats. They are designed to produce most energy below 100 Hz, but the pulses have also been reported to contain medium-to-high frequency components with the potential to affect small marine mammals, which have their best hearing sensitivity at higher frequencies. In shallow water environments, inhabited by many of such species, the impact of airgun noise may be particularly challenging to assess due to complex propagation conditions. To alleviate the current lack of knowledge on the characteristics and propagation of airgun pulses in shallow water with implications for effects on small marine mammals, we recorded pulses from a single airgun with three operating volumes (10 in3, 25 in3 and 40 in3) at six ranges (6, 120, 200, 400, 800 and 1300 m) in a uniform shallow water habitat using two calibrated Reson 4014 hydrophones and four DSG-Ocean acoustic data recorders. We show that airgun pulses in this shallow habitat propagated out to 1300 meters in a way that can be approximated by a 18log(r) geometric transmission loss model, but with a high pass filter effect from the shallow water depth. Source levels were back-calculated to 192 dB re µPa2s (sound exposure level) and 200 dB re 1 µPa dB Leq-fast (rms over 125 ms duration), and the pulses contained substantial energy up to 10 kHz, even at the furthest recording station at 1300 meters. We conclude that the risk of causing hearing damage when using single airguns in shallow waters is small for both pinnipeds and porpoises. However, there is substantial potential for significant behavioral responses out to several km from the airgun, well beyond the commonly used shut-down zone of 500 meters. PMID:26214849

  7. Schistosomes of small mammals from the Lake Victoria Basin, Kenya: new species, familiar species, and implications for schistosomiasis control.

    PubMed

    Hanelt, B; Mwangi, I N; Kinuthia, J M; Maina, G M; Agola, L E; Mutuku, M W; Steinauer, M L; Agwanda, B R; Kigo, L; Mungai, B N; Loker, E S; Mkoji, G M

    2010-06-01

    Recent schistosomiasis control efforts in sub-Saharan Africa have focused nearly exclusively on treatment of humans with praziquantel. However, the extent to which wild mammals act as reservoirs for Schistosoma mansoni and therefore as sources of renewed transmission following control efforts is poorly understood. With the objective to study the role of small mammals as reservoir hosts, 480 animals belonging to 9 rodent and 1 insectivore species were examined for infection with schistosomes in Kisumu, in the Lake Victoria Basin, Kenya. Animals were collected from 2 sites: near the lakeshore and from Nyabera Marsh draining into the lake. A total of 6.0% of the animals captured, including 5 murid rodent species and 1 species of shrew (Crocidura olivieri) were infected with schistosomes. Four schistosome species were recovered and identified using cox1 DNA barcoding: S. mansoni, S. bovis, S. rodhaini and S. kisumuensis, the latter of which was recently described from Nyabera Marsh. Schistosoma mansoni and S. rodhaini were found infecting the same host individual (Lophuromys flavopunctatus), suggesting that this host species could be responsible for the production of hybrid schistosomes found in the area. Although the prevalence of S. mansoni infection in these reservoir populations was low (1.5%), given their potentially vast population size, their impact on transmission needs further study. Reservoir hosts could perpetuate snail infections and favour renewed transmission to humans once control programmes have ceased.

  8. Sound localization in common vampire bats: Acuity and use of the binaural time cue by a small mammal

    PubMed Central

    Heffner, Rickye S.; Koay, Gimseong; Heffner, Henry E.

    2015-01-01

    Passive sound-localization acuity and the ability to use binaural time and intensity cues were determined for the common vampire bat (Desmodus rotundus). The bats were tested using a conditioned suppression/avoidance procedure in which they drank defibrinated blood from a spout in the presence of sounds from their right, but stopped drinking (i.e., broke contact with the spout) whenever a sound came from their left, thereby avoiding a mild shock. The mean minimum audible angle for three bats for a 100-ms noise burst was 13.1°—within the range of thresholds for other bats and near the mean for mammals. Common vampire bats readily localized pure tones of 20 kHz and higher, indicating they could use interaural intensity-differences. They could also localize pure tones of 5 kHz and lower, thereby demonstrating the use of interaural time-differences, despite their very small maximum interaural distance of 60 μs. A comparison of the use of locus cues among mammals suggests several implications for the evolution of sound localization and its underlying anatomical and physiological mechanisms. PMID:25618037

  9. Sound localization in common vampire bats: acuity and use of the binaural time cue by a small mammal.

    PubMed

    Heffner, Rickye S; Koay, Gimseong; Heffner, Henry E

    2015-01-01

    Passive sound-localization acuity and the ability to use binaural time and intensity cues were determined for the common vampire bat (Desmodus rotundus). The bats were tested using a conditioned suppression/avoidance procedure in which they drank defibrinated blood from a spout in the presence of sounds from their right, but stopped drinking (i.e., broke contact with the spout) whenever a sound came from their left, thereby avoiding a mild shock. The mean minimum audible angle for three bats for a 100-ms noise burst was 13.1°-within the range of thresholds for other bats and near the mean for mammals. Common vampire bats readily localized pure tones of 20 kHz and higher, indicating they could use interaural intensity-differences. They could also localize pure tones of 5 kHz and lower, thereby demonstrating the use of interaural time-differences, despite their very small maximum interaural distance of 60 μs. A comparison of the use of locus cues among mammals suggests several implications for the evolution of sound localization and its underlying anatomical and physiological mechanisms.

  10. First Isolation and Direct Evidence for the Existence of Large Small-Mammal Reservoirs of Leptospira sp. in Madagascar

    PubMed Central

    Rahelinirina, Soanandrasana; Léon, Albertine; Harstskeerl, Rudy A.; Sertour, Natacha; Ahmed, Ahmed; Raharimanana, Claudine; Ferquel, Elisabeth; Garnier, Martine; Chartier, Loïc; Duplantier, Jean-Marc; Rahalison, Lila; Cornet, Muriel

    2010-01-01

    Background Leptospirosis has long been a major public health concern in the southwestern Indian Ocean. However, in Madagascar, only a few, old studies have provided indirect serological evidence of the disease in humans or animals. Methodology/Principal Findings We conducted a large animal study focusing on small-mammal populations. Five field trapping surveys were carried out at five sites, from April 2008 to August 2009. Captures consisted of Rattus norvegicus (35.8%), R. rattus (35.1%), Mus musculus (20.5%) and Suncus murinus (8.6%). We used microbiological culture, serodiagnosis tests (MAT) and real-time PCR to assess Leptospira infection. Leptospira carriage was detected by PCR in 91 (33.9%) of the 268 small mammals, by MAT in 17 of the 151 (11.3%) animals for which serum samples were available and by culture in 9 of the 268 animals (3.3%). Rates of infection based on positive PCR results were significantly higher in Moramanga (54%), Toliara (48%) and Mahajanga (47.4%) than in Antsiranana (8.5%) and Toamasina (14%) (p = 0.001). The prevalence of Leptospira carriage was significantly higher in R. norvegicus (48.9%), S. murinus (43.5%) and R. rattus (30.8%) than in M. musculus (9.1%) (p<0.001). The MAT detected antibodies against the serogroups Canicola and Icterohaemorrhagiae. Isolates were characterized by serology, secY sequence-based phylogeny, partial sequencing of rrs, multi-locus VNTR analysis and pulsed field gel electrophoresis. The 10 isolates obtained from nine rats were all identified as species L. interrogans serogroup Canicola serovar Kuwait and all had identical partial rrs and secY sequences. Conclusions/Significance We present here the first direct evidence of widespread leptospiral carriage in small mammals in Madagascar. Our results strongly suggest a high level of environmental contamination, consistent with probable transmission of the infection to humans. This first isolation of pathogenic Leptospira strains in this country may

  11. Endocrine mechanisms of seasonal adaptation in small mammals: from early results to present understanding.

    PubMed

    Scherbarth, Frank; Steinlechner, Stephan

    2010-10-01

    Seasonal adaptation is widespread among mammals of temperate and polar latitudes. The changes in physiology, morphology and behaviour are controlled by the photoneuroendocrine system that, as a first step, translates day lengths into a hormonal signal (melatonin). Decoding of the humoral melatonin signal, i.e. responses on the cellular level to slight alterations in signal duration, represents the prerequisite for appropriate timing of winter acclimatization in photoperiodic animals. Corresponding to the diversity of affected traits, several hormone systems are involved in the regulation downstream of the neural integration of photoperiodic time measurement. Results from recent studies provide new insights into seasonal control of reproduction and energy balance. Most intriguingly, the availability of thyroid hormone within hypothalamic key regions, which is a crucial determinant of seasonal transitions, appears to be regulated by hormone secretion from the pars tuberalis of the pituitary gland. This proposed neuroendocrine pathway contradicts the common view of the pituitary as a gland that acts downstream of the hypothalamus. In the present overview of (neuro)endocrine mechanisms underlying seasonal acclimatization, we are focusing on the dwarf hamster Phodopus sungorus (long-day breeder) that is known for large amplitudes in seasonal changes. However, important findings in other mammalian species such as Syrian hamsters and sheep (short-day breeder) are considered as well.

  12. The Fleas of Endemic and Introduced Small Mammals in Central Highland Forests of Madagascar: Faunistics, Species Diversity, and Absence of Host Specificity.

    PubMed

    Goodman, Steven M; Randrenjarison Andriniaina, H Rico; Soarimalala, Voahangy; Beaucournu, Jean-Claude

    2015-09-01

    Data are presented on the flea species of the genera Paractenopsyllus (Ceratophyllidae, Leptopsyllinae) and Synopsyllus (Pulicidae, Xenopsyllinae) obtained from small mammals during two 2014 seasonal surveys at a montane humid forest site (Ambohitantely) in the Central Highlands of Madagascar. The mammal groups included the endemic family Tenrecidae (tenrecs) and subfamily Nesomyinae (rodents) and two introduced families Muridae (rodents) and Soricidae (shrews); no fleas were recovered from the latter family. The surveys were conducted at the end of the wet and dry seasons with 288 individual small mammals captured, including 12 endemic and four introduced species. These animals yielded 344 fleas, representing nine species endemic to Madagascar; no introduced species was collected. Some seasonal variation was found in the number of trapped small mammals, but no marked difference was found in species richness. For flea species represented by sufficient samples, no parasite-host specificity was found, and there is evidence for considerable lateral exchange in the local flea fauna between species of tenrecs and the two rodent families (endemic and introduced). The implications of these results are discussed with regards to small mammal species richness and community structure, as well as a possible mechanism for the maintenance of sylvatic cycles of bubonic plague in the montane forests of Madagascar.

  13. Small mammal utilization by Middle Stone Age humans at Die Kelders Cave 1 and Pinnacle Point Site 5-6, Western Cape Province, South Africa.

    PubMed

    Armstrong, Aaron

    2016-12-01

    Reported here are the results of a taphonomic analysis of the small mammals (between 0.75 kg and 4.5 kg adult body weight) and size 1 bovids (≤20 kg adult body weight) from the Middle Stone Age (MSA) sites of Die Kelders Cave 1 (DK1) and Pinnacle Point Site 5-6 (PP5-6), Western Cape Province, South Africa. This study provides a comprehensive taphonomic analysis of MSA small mammals with a focus on discerning the role of humans in their accumulation and the implications for human behavioral adaptations. Based on comparisons with control assemblages of known accumulation, it is evident that humans accumulated many of the Cape dune mole-rats, hares, and size 1 bovids at DK1. The patterning of cut-marked and burned mole-rat remains at DK1 provides evidence in the MSA for the systematic utilization of small mammals for their skins and as a protein source. Unlike DK1, small mammals and size 1 bovids constitute only a small portion of the PP5-6 mammals and they exhibit little evidence of human accumulation. Nocturnal and diurnal raptors accumulated most of the small fauna at PP5-6. The nominal presence of small mammals in the PP5-6 fauna is atypical of MSA sites in the Cape Floristic Region, where they are abundant and often constitute large portions of MSA archaeofaunas. DK1 humans maximized the environmental yield by exploiting low-quality resources, a strategy employed possibly in response to localized environmental conditions and to greater human population densities. In comparison, the MIS5-4 humans at PP5-6 did not exploit small mammals and instead focused on higher-quality resources like shellfish and large ungulates. Humans and predators accumulated few small mammals at PP5-6, suggesting that these taxa may have been less abundant near the site and/or that humans could afford to concentrate on high-quality resources, perhaps because of a higher-yield local environment. This study suggests that an adaptive response to the environmental conditions of MIS4 was

  14. The use of a robust capture-recapture design in small mammal population studies: A field example with Microtus pennsylvanicus

    USGS Publications Warehouse

    Nichols, J.D.; Pollock, K.H.; Hines, J.E.

    1984-01-01

    The robust design of Pollock (1982) was used to estimate parameters of a Maryland M. pennsylvanicus population. Closed model tests provided strong evidence of heterogeneity of capture probability, and model M eta (Otis et al., 1978) was selected as the most appropriate model for estimating population size. The Jolly-Seber model goodness-of-fit test indicated rejection of the model for this data set, and the M eta estimates of population size were all higher than the Jolly-Seber estimates. Both of these results are consistent with the evidence of heterogeneous capture probabilities. The authors thus used M eta estimates of population size, Jolly-Seber estimates of survival rate, and estimates of birth-immigration based on a combination of the population size and survival rate estimates. Advantages of the robust design estimates for certain inference procedures are discussed, and the design is recommended for future small mammal capture-recapture studies directed at estimation.

  15. Biological control of saltcedar (Tamarix spp.) by saltcedar leaf beetles (Diorhabda spp.): effects on small mammals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The spread of introduced saltcedar (Tamarix spp.) throughout many riparian systems across the western United States motivated the introduction of biological control agents that are specific to saltcedar, saltcedar leaf beetles (Diorhabda carinulata, D. elongata; Chrysomelidae). I monitored small mam...

  16. Phenotypic plasticity of post-fire activity and thermal biology of a free-ranging small mammal.

    PubMed

    Stawski, Clare; Körtner, Gerhard; Nowack, Julia; Geiser, Fritz

    2016-05-15

    Ecosystems can change rapidly and sometimes irreversibly due to a number of anthropogenic and natural factors, such as deforestation and fire. How individual animals exposed to such changes respond behaviourally and physiologically is poorly understood. We quantified the phenotypic plasticity of activity patterns and torpor use - a highly efficient energy conservation mechanism - in brown antechinus (Antechinus stuartii), a small Australian marsupial mammal. We compared groups in densely vegetated forest areas (pre-fire and control) with a group in a burned, open habitat (post-fire). Activity and torpor patterns differed among groups and sexes. Females in the post-fire group spent significantly less time active than the other groups, both during the day and night. However, in males only daytime activity declined in the post-fire group, although overall activity was also reduced on cold days in males for all groups. The reduction in total or diurnal activity in the post-fire group was made energetically possible by a ~3.4-fold and ~2.2-fold increase in the proportion of time females and males, respectively, used torpor in comparison to that in the pre-fire and control groups. Overall, likely due to reproductive needs, torpor was more pronounced in females than in males, but low ambient temperatures increased torpor bout duration in both sexes. Importantly, for both male and female antechinus and likely other small mammals, predator avoidance and energy conservation - achieved by reduced activity and increased torpor use - appear to be vital for post-fire survival where ground cover and refuges have been obliterated.

  17. A Small Mammal Community in a Forest Fragment, Vegetation Corridor and Coffee Matrix System in the Brazilian Atlantic Forest

    PubMed Central

    Rocha, Mariana Ferreira; Passamani, Marcelo; Louzada, Júlio

    2011-01-01

    The objective of our work was to verify the value of the vegetation corridor in the conservation of small mammals in fragmented tropical landscapes, using a model system in the southeastern Minas Gerais. We evaluated and compared the composition and structure of small mammals in a vegetation corridor, forest fragments and a coffee matrix. A total of 15 species were recorded, and the highest species richness was observed in the vegetation corridor (13 species), followed by the forest fragments (10) and the coffee matrix (6). The absolute abundance was similar between the vegetation corridor and fragments (F = 22.94; p = 0.064), and the greatest differences occurred between the vegetation corridor and the matrix (F = 22.94; p = 0.001) and the forest fragments and the matrix (F = 22.94; p = 0.007). Six species showed significant habitat preference possibly related to the sensitivity of the species to the forest disturbance. Marmosops incanus was the species most sensitive to disturbance; Akodon montensis, Cerradomys subflavus, Gracilinanus microtarsus and Rhipidomys sp. displayed little sensitivity to disturbance, with a high relative abundance in the vegetation corridor. Calomys sp. was the species least affected by habitat disturbance, displaying a high relative abundance in the coffee matrix. Although the vegetation corridors are narrow (4 m width), our results support the hypothesis in which they work as a forest extension, share most species with the forest fragment and support species richness and abundance closer to forest fragments than to the coffee matrix. Our work highlights the importance and cost-effectiveness of these corridors to biodiversity management in the fragmented Atlantic Forest landscapes and at the regional level. PMID:21912591

  18. A small mammal community in a forest fragment, vegetation corridor and coffee matrix system in the Brazilian Atlantic forest.

    PubMed

    Rocha, Mariana Ferreira; Passamani, Marcelo; Louzada, Júlio

    2011-01-01

    The objective of our work was to verify the value of the vegetation corridor in the conservation of small mammals in fragmented tropical landscapes, using a model system in the southeastern Minas Gerais. We evaluated and compared the composition and structure of small mammals in a vegetation corridor, forest fragments and a coffee matrix. A total of 15 species were recorded, and the highest species richness was observed in the vegetation corridor (13 species), followed by the forest fragments (10) and the coffee matrix (6). The absolute abundance was similar between the vegetation corridor and fragments (F = 22.94; p = 0.064), and the greatest differences occurred between the vegetation corridor and the matrix (F = 22.94; p = 0.001) and the forest fragments and the matrix (F = 22.94; p = 0.007). Six species showed significant habitat preference possibly related to the sensitivity of the species to the forest disturbance. Marmosops incanus was the species most sensitive to disturbance; Akodon montensis, Cerradomys subflavus, Gracilinanus microtarsus and Rhipidomys sp. displayed little sensitivity to disturbance, with a high relative abundance in the vegetation corridor. Calomys sp. was the species least affected by habitat disturbance, displaying a high relative abundance in the coffee matrix. Although the vegetation corridors are narrow (4 m width), our results support the hypothesis in which they work as a forest extension, share most species with the forest fragment and support species richness and abundance closer to forest fragments than to the coffee matrix. Our work highlights the importance and cost-effectiveness of these corridors to biodiversity management in the fragmented Atlantic Forest landscapes and at the regional level.

  19. Small mammals as sentinels of oil sands related contaminants and health effects in northeastern Alberta, Canada.

    PubMed

    Rodríguez-Estival, Jaime; Smits, Judit E G

    2016-02-01

    The extraction of bitumen in areas of northeastern Alberta (Canada) has been associated with the release of complex mixtures of metals, metalloids, and polycyclic aromatic compounds (PACs) to the environment. To mitigate effects on ecosystems, Canadian legislation mandates that disturbed areas be reclaimed to an ecologically sustainable state after active operations. However, as part of reclamation activities, exposure to, and effects on wildlife living in these areas is not generally assessed. To support successful reclamation, the development of efficient methods to assess exposure and health effects in potentially exposed wildlife is required. In the present study, we investigated the usefulness of two native mammalian species (deer mouse Peromyscus maniculatus, and meadow vole Microtus pennsylvanicus) as sentinels of oil sands related contaminants by examining biomarkers of exposure and indicators of biological costs. Tissue residues of 31 metals and metalloids in kidneys and muscle, activity of the hepatic detoxification enzyme EROD (as a biomarker of exposure to organic contaminants), body condition, and the relative mass of liver, kidney, spleen, and testes were compared in animals from one reclaimed area and a reference site. Deer mice from the reclaimed site had higher renal levels of Co, Se and Tl compared to animals from the reference site, which was associated with reduced body condition. Lower testis mass was another feature that distinguished mice from the reclaimed site in comparison to those from the reference site. One mouse and one vole from the reclaimed site also showed increased hepatic EROD activity. In marked contrast, no changes were evident for these variables in meadow voles. Our results show that deer mouse is a sensitive sentinel species and that the biomarkers and indicators used here are efficient means to detect local contamination and associated biological effects in native mammals inhabiting reclaimed areas on active oil sands mine

  20. Feasibility study of a small, thorium-based fission power system for space and terrestrial applications

    NASA Astrophysics Data System (ADS)

    Worrall, Michael Jason

    One of the current challenges facing space exploration is the creation of a power source capable of providing useful energy for the entire duration of a mission. Historically, radioisotope batteries have been used to provide load power, but this conventional system may not be capable of sustaining continuous power for longer duration missions. To remedy this, many forays into nuclear powered spacecraft have been investigated, but no robust system for long-term power generation has been found. In this study, a novel spin on the traditional fission power system that represents a potential optimum solution is presented. By utilizing mature High Temperature Gas Reactor (HTGR) technology in conjunction with the capabilities of the thorium fuel cycle, we have created a light-weight, long-term power source capable of a continuous electric power output of up to 70kW for over 15 years. This system relies upon a combination of fissile, highly-enriched uranium dioxide and fertile thorium carbide Tri-Structural Isotropic (TRISO) fuel particles embedded in a hexagonal beryllium oxide matrix. As the primary fissile material is consumed, the fertile material breeds new fissile material leading to more steady fuel loading over the lifetime of the core. Reactor control is achieved through an innovative approach to the conventional boron carbide neutron absorber by utilizing sections of borated aluminum placed in rotating control drums within the reflector. Borated aluminum allows for much smaller boron concentrations, thus eliminating the potential for 10B(n,alpha)6Li heating issues that are common in boron carbide systems. A wide range of other reactivity control systems are also investigated, such as a radially-split rotating reflector. Lastly, an extension of the design to a terrestrial based system is investigated. In this system, uranium enrichment is dropped to 20 percent in order to meet current regulations, a solid uranium-zirconium hydride fissile driver replaces the

  1. New karyologycal data and cytotaxonomic considerations on small mammals from Santa Virgínia (Parque Estadual da Serra do Mar, Atlantic Forest, Brazil)

    PubMed Central

    Di-Nizo, Camilla Bruno; Neves, Carolina Lima; Vilela, Júlio Fernando; Silva, Maria José de J.

    2014-01-01

    Abstract Atlantic Forest, in the eastern coast of Brazil, is a hotspot of biodiversity of mammals, and Parque Estadual da Serra do Mar (PESM) is the largest continuous area of this biome. Here, we characterized the karyotype composition of the small mammals from Santa Virgínia, a region in the northern part of PESM. Specimens were collected from July 2008 to September 2009. We identified 17 species (13 rodents and 4 marsupials) from which 7 exhibited species-specific karyotypes, illustrating the importance of karyotype information in cytotaxonomy. We report for first time the karyotype of Monodelphis scalops (Thomas, 1888) and two new records for PESM: Akodon montensis Thomas, 1913 and Brucepattersonius soricinus Hershkovitz, 1998. Cytogenetic polymorphisms were detected for some species trapped in the area. Our results show the importance of Santa Virgínia / PESM in addressing studies for the conservation of small mammal wildlife in the Atlantic Forest. PMID:24744831

  2. New karyologycal data and cytotaxonomic considerations on small mammals from Santa Virgínia (Parque Estadual da Serra do Mar, Atlantic Forest, Brazil).

    PubMed

    Di-Nizo, Camilla Bruno; Neves, Carolina Lima; Vilela, Júlio Fernando; Silva, Maria José de J

    2014-01-01

    Atlantic Forest, in the eastern coast of Brazil, is a hotspot of biodiversity of mammals, and Parque Estadual da Serra do Mar (PESM) is the largest continuous area of this biome. Here, we characterized the karyotype composition of the small mammals from Santa Virgínia, a region in the northern part of PESM. Specimens were collected from July 2008 to September 2009. We identified 17 species (13 rodents and 4 marsupials) from which 7 exhibited species-specific karyotypes, illustrating the importance of karyotype information in cytotaxonomy. We report for first time the karyotype of Monodelphis scalops (Thomas, 1888) and two new records for PESM: Akodon montensis Thomas, 1913 and Brucepattersonius soricinus Hershkovitz, 1998. Cytogenetic polymorphisms were detected for some species trapped in the area. Our results show the importance of Santa Virgínia / PESM in addressing studies for the conservation of small mammal wildlife in the Atlantic Forest.

  3. Serosurveillance of Scrub Typhus in Small Mammals Collected from Military Training Sites near the DMZ, Northern Gyeonggi-do, Korea, and Analysis of the Relative Abundance of Chiggers from Mammals Examined

    DTIC Science & Technology

    2010-09-01

    Hilton Hotel , Seoul, Korea. 21. Fuller HS, Smadel JE. Rickettsial diseases and the Korean conflia. Medical Science Publication No. 4, Recent Advances...harvesting and other outdoor activities . Additionally, small mammal surveillance was conducted prior to the onset of the primary "scrub typhus...habitats at risk for scrub typhus. Cantonment sites are often established adjacent to tall grasses and forested margins, while training activities

  4. Small mammals and high elevation vegetation in Yosemite National Park could be responding to smaller temperature increases than previously reported

    NASA Astrophysics Data System (ADS)

    Conklin, D. R.; Daly, C.

    2009-12-01

    Recent research related the dynamics of Sierra Nevada subalpine conifers to 20th century warming, and used temperature records from Yosemite National Park headquarters and two other locations outside the Park to estimate a 3.7°C rise in average minimum temperature. More recently, observed elevational shifts of small mammals in Yosemite National Park were linked to the same upward trend in minimum monthly temperatures. However, our analysis of spatially explicit, monthly time series of temperatures, derived using the PRISM model, suggests that the large increase in minimum monthly temperatures may be limited to Yosemite Valley, where the Park headquarters itself is located. PRISM bases its interpolations on observations from 195 temperature recording stations within and near Yosemite National Park. Minimum monthly temperatures over most of the Park do not show a centennial-scale trend, but for the final quarter of the century they do trend upwards by 1°C. Our new estimate of the spatial and temporal pattern of 20th century changes in minimum temperatures in the Park could affect conclusions about the relative importance for subalpine conifers of the centennial trend compared to interdecadal variability of temperature. It also raises a question of whether the elevational shifts of the mammals took place only in the latter part of the century, and in response to smaller temperature increases. It challenges us to accept that these plants and animals are responding to smaller changes in minimum temperatures than previously estimated or else to find reasons other than an increase in minimum temperatures for the changes that have been documented, by these and other studies, over the last century in Yosemite.

  5. A nonlethal sampling method to obtain, generate and assemble whole blood transcriptomes from small, wild mammals.

    PubMed

    Huang, Zixia; Gallot, Aurore; Lao, Nga T; Puechmaille, Sébastien J; Foley, Nicole M; Jebb, David; Bekaert, Michaël; Teeling, Emma C

    2016-01-01

    The acquisition of tissue samples from wild populations is a constant challenge in conservation biology, especially for endangered species and protected species where nonlethal sampling is the only option. Whole blood has been suggested as a nonlethal sample type that contains a high percentage of bodywide and genomewide transcripts and therefore can be used to assess the transcriptional status of an individual, and to infer a high percentage of the genome. However, only limited quantities of blood can be nonlethally sampled from small species and it is not known if enough genetic material is contained in only a few drops of blood, which represents the upper limit of sample collection for some small species. In this study, we developed a nonlethal sampling method, the laboratory protocols and a bioinformatic pipeline to sequence and assemble the whole blood transcriptome, using Illumina RNA-Seq, from wild greater mouse-eared bats (Myotis myotis). For optimal results, both ribosomal and globin RNAs must be removed before library construction. Treatment of DNase is recommended but not required enabling the use of smaller amounts of starting RNA. A large proportion of protein-coding genes (61%) in the genome were expressed in the blood transcriptome, comparable to brain (65%), kidney (63%) and liver (58%) transcriptomes, and up to 99% of the mitogenome (excluding D-loop) was recovered in the RNA-Seq data. In conclusion, this nonlethal blood sampling method provides an opportunity for a genomewide transcriptomic study of small, endangered or critically protected species, without sacrificing any individuals.

  6. Radionuclides in Small Mammals Collected at the Dual-Axis Radiographic Hydrodynamic Test (DARHT) Facility during 2001-- 2003

    SciTech Connect

    P.R. Fresquez

    2005-01-20

    Rodents are effective indicators of environmental contamination and the Dual-Axis Radiographic Hydrodynamic Test (DARHT) Facility Mitigation Action Plan specifies the (radionuclide) comparison of small mammals to baseline levels to determine if there are any impacts as a result of operations. Consequently, samples of (whole body) field mice (Peromyscus spp.) were collected from within the grounds of the DARHT facility at Los Alamos National Laboratory, Technical Area 15, from 2001 through 2003. Samples were analyzed for {sup 3}H, {sup 137}Cs, {sup 90}Sr, {sup 241}Am, {sup 238}Pu, {sup 239,240}Pu, {sup 234}U, {sup 235}U, and {sup 238}U. Results, which represent three years since the start of operations in 2000, were compared with baseline statistical reference level (BSRL) data established over a four-year-long preoperational period. Most radionuclides in mice were either at nondetectable levels or within BSRLs. The few radionuclides that were above BSRLs included U isotopes; and the ratios of some samples indicated depleted U sources. Although the amounts of U in some samples were just above BSRLs, and since depleted U is less soluble and less toxic (chemical and radioactive) than naturally occurring U, the very small levels in the mice collected around the DARHT facility grounds are unlikely to pose a threat to predators that feed upon them.

  7. Adaptive sequence convergence of the tumor suppressor ADAMTS9 between small-bodied mammals displaying exceptional longevity.

    PubMed

    Lambert, Matthew J; Portfors, Christine V

    2017-02-26

    Maximum lifespan varies by two orders of magnitude across mammals. How such divergent lifespans have evolved remains an open question, with ramifications that may potentially lead to therapies for age-related diseases in humans. Several species of microbats as well as the naked mole-rat live much longer than expected given their small sizes, show reduced susceptibility to neoplasia, and largely remain healthy and reproductively capable throughout the majority of their extended lifespans. The convergent evolution of extreme longevity in these two groups allows for the opportunity to identify potentially important aging related genes that have undergone adaptive sequence convergence in these long-lived, yet small-bodied species. Here, we have tested 4,628 genes for evidence of convergence between the microbats and naked mole-rat. We find a strong signal of adaptive sequence convergence in the gene A disintegrin-like and metalloprotease with thrombospondin type 1 motifs 9 (ADAMTS9). We also provide evidence that the shared substitutions were driven by selection. Intriguingly, ADAMTS9 is a known inhibitor of the mTor pathway and has been implicated in several aging related processes.

  8. Adaptive sequence convergence of the tumor suppressor ADAMTS9 between small-bodied mammals displaying exceptional longevity

    PubMed Central

    Lambert, Matthew J.; Portfors, Christine V.

    2017-01-01

    Maximum lifespan varies by two orders of magnitude across mammals. How such divergent lifespans have evolved remains an open question, with ramifications that may potentially lead to therapies for age-related diseases in humans. Several species of microbats as well as the naked mole-rat live much longer than expected given their small sizes, show reduced susceptibility to neoplasia, and largely remain healthy and reproductively capable throughout the majority of their extended lifespans. The convergent evolution of extreme longevity in these two groups allows for the opportunity to identify potentially important aging related genes that have undergone adaptive sequence convergence in these long-lived, yet small-bodied species. Here, we have tested 4,628 genes for evidence of convergence between the microbats and naked mole-rat. We find a strong signal of adaptive sequence convergence in the gene A disintegrin-like and metalloprotease with thrombospondin type 1 motifs 9 (ADAMTS9). We also provide evidence that the shared substitutions were driven by selection. Intriguingly, ADAMTS9 is a known inhibitor of the mTor pathway and has been implicated in several aging related processes. PMID:28244876

  9. Permeability of roads to movement of scrubland lizards and small mammals.

    PubMed

    Brehme, Cheryl S; Tracey, Jeff A; McClenaghan, Leroy R; Fisher, Robert N

    2013-08-01

    A primary objective of road ecology is to understand and predict how roads affect connectivity of wildlife populations. Road avoidance behavior can fragment populations, whereas lack of road avoidance can result in high mortality due to wildlife-vehicle collisions. Many small animal species focus their activities to particular microhabitats within their larger habitat. We sought to assess how different types of roads affect the movement of small vertebrates and to explore whether responses to roads may be predictable on the basis of animal life history or microhabitat preferences preferences. We tracked the movements of fluorescently marked animals at 24 sites distributed among 3 road types: low-use dirt, low-use secondary paved, and rural 2-lane highway. Most data we collected were on the San Diego pocket mouse (Chaetodipus fallax), cactus mouse (Peromyscus eremicus), western fence lizard (Sceloporus occidentalis), orange-throated whiptail (Aspidoscelis hyperythra), Dulzura kangaroo rat (Dipodomys simulans) (dirt, secondary paved), and deer mouse (Peromyscus maniculatus) (highway only). San Diego pocket mice and cactus mice moved onto dirt roads but not onto a low-use paved road of similar width or onto the highway, indicating they avoid paved road substrate. Both lizard species moved onto the dirt and secondary paved roads but avoided the rural 2-lane rural highway, indicating they may avoid noise, vibration, or visual disturbance from a steady flow of traffic. Kangaroo rats did not avoid the dirt or secondary paved roads. Overall, dirt and secondary roads were more permeable to species that prefer to forage or bask in open areas of their habitat, rather than under the cover of rocks or shrubs. However, all study species avoided the rural 2-lane highway. Our results suggest that microhabitat use preferences and road substrate help predict species responses to low-use roads, but roads with heavy traffic may deter movement of a much wider range of small animal

  10. Permeability of roads to movement of scrubland lizards and small mammals

    USGS Publications Warehouse

    Brehme, Cheryl S.; Tracey, Jeff A.; McClenaghan, Leroy R.; Fisher, Robert N.

    2013-01-01

    A primary objective of road ecology is to understand and predict how roads affect connectivity of wildlife populations. Road avoidance behavior can fragment populations, whereas lack of road avoidance can result in high mortality due to wildlife-vehicle collisions. Many small animal species focus their activities to particular microhabitats within their larger habitat. We sought to assess how different types of roads affect the movement of small vertebrates and to explore whether responses to roads may be predictable on the basis of animal life history or microhabitat preferences preferences. We tracked the movements of fluorescently marked animals at 24 sites distributed among 3 road types: low-use dirt, low-use secondary paved, and rural 2-lane highway. Most data we collected were on the San Diego pocket mouse (Chaetodipus fallax), cactus mouse (Peromyscus eremicus), western fence lizard (Sceloporus occidentalis), orange-throated whiptail (Aspidoscelis hyperythra), Dulzura kangaroo rat (Dipodomys simulans) (dirt, secondary paved), and deer mouse (Peromyscus maniculatus) (highway only). San Diego pocket mice and cactus mice moved onto dirt roads but not onto a low-use paved road of similar width or onto the highway, indicating they avoidpaved road substrate. Both lizard species moved onto the dirt and secondary paved roads but avoided the rural 2-lane rural highway, indicating they may avoid noise, vibration, or visual disturbance from a steady flow of traffic. Kangaroo rats did not avoid the dirt or secondary paved roads. Overall, dirt and secondary roads were more permeable to species that prefer to forage or bask in open areas of their habitat, rather than under the cover of rocks or shrubs. However, all study species avoided the rural 2-lane highway. Our results suggest that microhabitat use preferences and road substrate help predict species responses to low-use roads,but roads with heavy traffic may deter movement of a much wider range of small animal

  11. Principles of wound management of small mammals: hedgehogs, prairie dogs, and sugar gliders.

    PubMed

    Hernandez-Divers, Sonia M

    2004-01-01

    The management of wounds is a common scenario for the exotic animal practitioner. When presented with such cases, the practitioner must first adhere to the firmly established principles of wound healing, and then modify available treatment modalities to fit the needs of the species at hand. Practicing wound management on exotic patients can be challenging due to their small size, unusual anatomy, difficult behaviors, and tendency for developing secondary stress-related health problems. A review of the stages of wound healing as well as traditional wound management techniques is provided here. This review is followed by a summary of typical wounds encountered in hedgehogs, prairie dogs, and sugar gliders, as well anatomic, physiologic, and behavioral characteristics that should be taken into consideration when managing wounds on such species.

  12. Morbilliviruses in marine mammals.

    PubMed

    Hall, A J

    1995-01-01

    Two of the three recently discovered aquatic morbilliviruses have been responsible for mass mortalities among marine mammals; both affect more than one host species, but susceptibility to infection varies considerably between species. Apparent differences between the dynamics of aquatic morbilliviruses and their terrestrial counterparts may be a consequence of high levels of interspecific transmission.

  13. Hantaan virus surveillance targeting small mammals at nightmare range, a high elevation military training area, Gyeonggi Province, Republic of Korea.

    PubMed

    Klein, Terry A; Kim, Heung-Chul; Chong, Sung-Tae; Kim, Jeong-Ah; Lee, Sook-Young; Kim, Won-Keun; Nunn, Peter V; Song, Jin-Won

    2015-01-01

    Rodent-borne disease surveillance was conducted at Nightmare Range (NM-R), near the demilitarized zone in northeast Gyeonggi Province, Republic of Korea, to identify hemorrhagic fever with renal syndrome (HFRS) risks for a mountainous high-elevation (500 m) military training site. Monthly surveys were conducted from January 2008-December 2009. A total of 1,720 small mammals were captured belonging to the Orders Rodentia [Families, Sciuridae (1 species) and Muridae (7 species)] and Soricomorpha [Family, Soricidae (1species)]. Apodemus agrarius, the primary reservoir for Hantaan virus (HTNV), accounted for 89.9% (1,546) of all small mammals captured, followed by Myodes regulus (4.0%), Crocidura lasiura (3.9%), Micromys minutus (1.4%), Mus musculus (0.3%), Microtus fortis (0.2%), Apodemus peninsulae (0.2%), Tamias sibiricus (0.1%), and Rattus norvegicus (<0.1%). Three species were antibody-positive (Ab+) for hantaviruses: A. agrarius (8.2%), M. minutus (4.2%), and C. lasiura (1.5%). HTNV specific RNA was detected in 93/127 Ab+ A. agrarius, while Imjin virus specific RNA was detected in 1/1 Ab+ C. lasiura. Overall, hantavirus Ab+ rates for A. agrarius increased with weight (age) and were significantly higher among males (10.9%) than females (5.1%) (P<0.0001). High A. agrarius gravid rates during the fall (August-September) were associated with peak numbers of HFRS cases in Korea that followed high gravid rates. From 79 RT-PCR positive A. agrarius, 12 HTNV RNA samples were sequenced and compared phylogenetically based on a 320 nt sequence from the GC glycoprotein-encoding M segment. These results demonstrate that the HTNV isolates from NM-R are distinctly separated from HTNV isolated from the People's Republic of China. These studies provide for improved disease risk assessments that identify military activities, rodent HTNV rates, and other factors associated with the transmission of hantaviruses during field training exercises.

  14. Hantaan Virus Surveillance Targeting Small Mammals at Nightmare Range, a High Elevation Military Training Area, Gyeonggi Province, Republic of Korea

    PubMed Central

    Klein, Terry A.; Kim, Heung-Chul; Chong, Sung-Tae; Kim, Jeong-Ah; Lee, Sook-Young; Kim, Won-Keun; Nunn, Peter V.; Song, Jin-Won

    2015-01-01

    Rodent-borne disease surveillance was conducted at Nightmare Range (NM-R), near the demilitarized zone in northeast Gyeonggi Province, Republic of Korea, to identify hemorrhagic fever with renal syndrome (HFRS) risks for a mountainous high-elevation (500 m) military training site. Monthly surveys were conducted from January 2008-December 2009. A total of 1,720 small mammals were captured belonging to the Orders Rodentia [Families, Sciuridae (1 species) and Muridae (7 species)] and Soricomorpha [Family, Soricidae (1species)]. Apodemus agrarius, the primary reservoir for Hantaan virus (HTNV), accounted for 89.9% (1,546) of all small mammals captured, followed by Myodes regulus (4.0%), Crocidura lasiura (3.9%), Micromys minutus (1.4%), Mus musculus (0.3%), Microtus fortis (0.2%), Apodemus peninsulae (0.2%), Tamias sibiricus (0.1%), and Rattus norvegicus (<0.1%). Three species were antibody-positive (Ab+) for hantaviruses: A. agrarius (8.2%), M. minutus (4.2%), and C. lasiura (1.5%). HTNV specific RNA was detected in 93/127 Ab+ A. agrarius, while Imjin virus specific RNA was detected in 1/1 Ab+ C. lasiura. Overall, hantavirus Ab+ rates for A. agrarius increased with weight (age) and were significantly higher among males (10.9%) than females (5.1%) (P<0.0001). High A. agrarius gravid rates during the fall (August-September) were associated with peak numbers of HFRS cases in Korea that followed high gravid rates. From 79 RT-PCR positive A. agrarius, 12 HTNV RNA samples were sequenced and compared phylogenetically based on a 320 nt sequence from the GC glycoprotein-encoding M segment. These results demonstrate that the HTNV isolates from NM-R are distinctly separated from HTNV isolated from the People’s Republic of China. These studies provide for improved disease risk assessments that identify military activities, rodent HTNV rates, and other factors associated with the transmission of hantaviruses during field training exercises. PMID:25874643

  15. An annotated catalogue of the gamasid mites associated with small mammals in Asiatic Russia. The family Laelapidae s. str. (Acari: Mesostigmata: Gamasina).

    PubMed

    Vinarski, Maxim V; Korallo-Vinarskaya, Natalia P

    2016-05-16

    Twenty-nine species of mites of the family Laelapidae s. str. have been recorded as associated with small mammals (rodents, insectivores) in Asiatic Russia (Siberia and the Russian Far East). These species belong to two subfamilies (Laelapinae, Myonyssinae) and six genera: Androlaelaps Berlese, 1903, Dipolaelaps Zemskaya & Piontkovskaya, 1960, Laelaps C.L. Koch, 1836, Hyperlaelaps Zakhvatkin, 1948, Myonyssus Tiraboschi, 1904, Oryctolaelaps Lange, 1955. A list of the species, with data on synonymy, geographic ranges, and relationships with mammal hosts is provided. Some considerations concerning patterns of distribution of the parasitic Laelaptidae of Asiatic Russia are presented as well as their classifications from the point of view of known host association records.

  16. Evolution of bone compactness in extant and extinct moles (Talpidae): exploring humeral microstructure in small fossorial mammals

    PubMed Central

    2013-01-01

    Background Talpids include forms with different degree of fossoriality, with major specializations in the humerus in the case of the fully fossorial moles. We studied the humeral microanatomy of eleven extant and eight extinct talpid taxa of different lifestyles and of two non-fossorial outgroups and examined the effects of size and phylogeny. We tested the hypothesis that bone microanatomy is different in highly derived humeri of fossorial taxa than in terrestrial and semi-aquatic ones, likely due to special mechanical strains to which they are exposed to during digging. This study is the first comprehensive examination of histological parameters in an ecologically diverse and small-sized mammalian clade. Results No pattern of global bone compactness was found in the humeri of talpids that could be related to biomechanical specialization, phylogeny or size. The transition zone from the medullary cavity to the cortical compacta was larger and the ellipse ratio smaller in fossorial talpids than in non-fossorial talpids. No differences were detected between the two distantly related fossorial clades, Talpini and Scalopini. Conclusions At this small size, the overall morphology of the humerus plays a predominant role in absorbing the load, and microanatomical features such as an increase in bone compactness are less important, perhaps due to insufficient gravitational effects. The ellipse ratio of bone compactness shows relatively high intraspecific variation, and therefore predictions from this ratio based on single specimens are invalid. PMID:23442022

  17. A Small Protein Associated with Fungal Energy Metabolism Affects the Virulence of Cryptococcus neoformans in Mammals

    PubMed Central

    Cox, James; Nakouzi, Antonio; Prabu, Moses M.; Almo, Steven C.

    2016-01-01

    The pathogenic yeast Cryptococcus neoformans causes cryptococcosis, a life-threatening fungal disease. C. neoformans has multiple virulence mechanisms that are non-host specific, induce damage and interfere with immune clearance. Microarray analysis of C. neoformans strains serially passaged in mice associated a small gene (CNAG_02591) with virulence. This gene, hereafter identified as HVA1 (hypervirulence-associated protein 1), encodes a protein that has homologs of unknown function in plant and animal fungi, consistent with a conserved mechanism. Expression of HVA1 was negatively correlated with virulence and was reduced in vitro and in vivo in both mouse- and Galleria-passaged strains of C. neoformans. Phenotypic analysis in hva1Δ and hva1Δ+HVA1 strains revealed no significant differences in established virulence factors. Mice infected intravenously with the hva1Δ strain had higher fungal burden in the spleen and brain, but lower fungal burden in the lungs, and died faster than mice infected with H99W or the hva1Δ+HVA1 strain. Metabolomics analysis demonstrated a general increase in all amino acids measured in the disrupted strain and a block in the TCA cycle at isocitrate dehydrogenase, possibly due to alterations in the nicotinamide cofactor pool. Macrophage fungal burden experiments recapitulated the mouse hypervirulent phenotype of the hva1Δ strain only in the presence of exogenous NADPH. The crystal structure of the Hva1 protein was solved, and a comparison of structurally similar proteins correlated with the metabolomics data and potential interactions with NADPH. We report a new gene that modulates virulence through a mechanism associated with changes in fungal metabolism. PMID:27583447

  18. Epizootiological study of rodent-borne hepatitis E virus HEV-C1 in small mammals in Hanoi, Vietnam.

    PubMed

    Obana, Satomu; Shimizu, Kenta; Yoshimatsu, Kumiko; Hasebe, Futoshi; Hotta, Kozue; Isozumi, Rie; Nguyen, Hoa Thuy; LE, Mai Quynh; Yamashiro, Tetsu; Tsuda, Yoshimi; Arikawa, Jiro

    2017-01-20

    There is concern about the zoonotic potential of rodent-borne hepatitis E virus, designated as HEV-C1. However, epizootiological information about HEV-C1 is limited. To address this issue, serum samples from 443 small mammals captured at 5 sites in Hanoi, Vietnam, were examined for anti-HEV-C1 IgG antibodies. In addition, livers of seropositive animals were examined for viral RNA. Anti-HEV-C1 antibodies were detected in 57 (12.9%) of the 443 serum samples. Seropositive animals were found in all of the sites (4.7% to 22.2%). Anti-HEV-C1 antibodies were detected from 48 (12.3%) of 389 Rattus norvegicus and 9 (19.6%) of 46 R. tanezumi, but were not detected from 8 Suncus murinus. Viral RNAs were detected from 13 (22.8%) of the 57 seropositive rodents. The detection rate of viral RNA in seropositive R. tanezumi (66.7%, 6/9) was significantly higher than that in seropositive R. norvegicus (14.6%, 7/48). The results suggest that R. tanezumi is more susceptible than R. norvegicus to HEV-C1 infection. Phylogenetic analysis revealed that Vietnamese strains were divided into 3 clusters in genetic group 2 of HEV-C1. Multiple clusters of viruses were detected at several sites without species specificity, suggesting that 3 clusters of HEV-C1 co-circulate in Hanoi, Vietnam.

  19. Detecting and modelling delayed density-dependence in abundance time series of a small mammal (Didelphis aurita).

    PubMed

    Brigatti, E; Vieira, M V; Kajin, M; Almeida, P J A L; de Menezes, M A; Cerqueira, R

    2016-02-11

    We study the population size time series of a Neotropical small mammal with the intent of detecting and modelling population regulation processes generated by density-dependent factors and their possible delayed effects. The application of analysis tools based on principles of statistical generality are nowadays a common practice for describing these phenomena, but, in general, they are more capable of generating clear diagnosis rather than granting valuable modelling. For this reason, in our approach, we detect the principal temporal structures on the bases of different correlation measures, and from these results we build an ad-hoc minimalist autoregressive model that incorporates the main drivers of the dynamics. Surprisingly our model is capable of reproducing very well the time patterns of the empirical series and, for the first time, clearly outlines the importance of the time of attaining sexual maturity as a central temporal scale for the dynamics of this species. In fact, an important advantage of this analysis scheme is that all the model parameters are directly biologically interpretable and potentially measurable, allowing a consistency check between model outputs and independent measurements.

  20. Detecting and modelling delayed density-dependence in abundance time series of a small mammal (Didelphis aurita)

    PubMed Central

    Brigatti, E.; Vieira, M. V.; Kajin, M.; Almeida, P. J. A. L.; de Menezes, M. A.; Cerqueira, R.

    2016-01-01

    We study the population size time series of a Neotropical small mammal with the intent of detecting and modelling population regulation processes generated by density-dependent factors and their possible delayed effects. The application of analysis tools based on principles of statistical generality are nowadays a common practice for describing these phenomena, but, in general, they are more capable of generating clear diagnosis rather than granting valuable modelling. For this reason, in our approach, we detect the principal temporal structures on the bases of different correlation measures, and from these results we build an ad-hoc minimalist autoregressive model that incorporates the main drivers of the dynamics. Surprisingly our model is capable of reproducing very well the time patterns of the empirical series and, for the first time, clearly outlines the importance of the time of attaining sexual maturity as a central temporal scale for the dynamics of this species. In fact, an important advantage of this analysis scheme is that all the model parameters are directly biologically interpretable and potentially measurable, allowing a consistency check between model outputs and independent measurements. PMID:26865413

  1. Epizootiological study of rodent-borne hepatitis E virus HEV-C1 in small mammals in Hanoi, Vietnam

    PubMed Central

    OBANA, Satomu; SHIMIZU, Kenta; YOSHIMATSU, Kumiko; HASEBE, Futoshi; HOTTA, Kozue; ISOZUMI, Rie; NGUYEN, Hoa Thuy; LE, Mai Quynh; YAMASHIRO, Tetsu; TSUDA, Yoshimi; ARIKAWA, Jiro

    2016-01-01

    There is concern about the zoonotic potential of rodent-borne hepatitis E virus, designated as HEV-C1. However, epizootiological information about HEV-C1 is limited. To address this issue, serum samples from 443 small mammals captured at 5 sites in Hanoi, Vietnam, were examined for anti-HEV-C1 IgG antibodies. In addition, livers of seropositive animals were examined for viral RNA. Anti-HEV-C1 antibodies were detected in 57 (12.9%) of the 443 serum samples. Seropositive animals were found in all of the sites (4.7% to 22.2%). Anti-HEV-C1 antibodies were detected from 48 (12.3%) of 389 Rattus norvegicus and 9 (19.6%) of 46 R. tanezumi, but were not detected from 8 Suncus murinus. Viral RNAs were detected from 13 (22.8%) of the 57 seropositive rodents. The detection rate of viral RNA in seropositive R. tanezumi (66.7%, 6/9) was significantly higher than that in seropositive R. norvegicus (14.6%, 7/48). The results suggest that R. tanezumi is more susceptible than R. norvegicus to HEV-C1 infection. Phylogenetic analysis revealed that Vietnamese strains were divided into 3 clusters in genetic group 2 of HEV-C1. Multiple clusters of viruses were detected at several sites without species specificity, suggesting that 3 clusters of HEV-C1 co-circulate in Hanoi, Vietnam. PMID:27795461

  2. Detecting and modelling delayed density-dependence in abundance time series of a small mammal (Didelphis aurita)

    NASA Astrophysics Data System (ADS)

    Brigatti, E.; Vieira, M. V.; Kajin, M.; Almeida, P. J. A. L.; de Menezes, M. A.; Cerqueira, R.

    2016-02-01

    We study the population size time series of a Neotropical small mammal with the intent of detecting and modelling population regulation processes generated by density-dependent factors and their possible delayed effects. The application of analysis tools based on principles of statistical generality are nowadays a common practice for describing these phenomena, but, in general, they are more capable of generating clear diagnosis rather than granting valuable modelling. For this reason, in our approach, we detect the principal temporal structures on the bases of different correlation measures, and from these results we build an ad-hoc minimalist autoregressive model that incorporates the main drivers of the dynamics. Surprisingly our model is capable of reproducing very well the time patterns of the empirical series and, for the first time, clearly outlines the importance of the time of attaining sexual maturity as a central temporal scale for the dynamics of this species. In fact, an important advantage of this analysis scheme is that all the model parameters are directly biologically interpretable and potentially measurable, allowing a consistency check between model outputs and independent measurements.

  3. Silvicolous on a Small Scale: Possibilities and Limitations of Habitat Suitability Models for Small, Elusive Mammals in Conservation Management and Landscape Planning

    PubMed Central

    2015-01-01

    Species distribution and endangerment can be assessed by habitat-suitability modelling. This study addresses methodical aspects of habitat suitability modelling and includes an application example in actual species conservation and landscape planning. Models using species presence-absence data are preferable to presence-only models. In contrast to species presence data, absences are rarely recorded. Therefore, many studies generate pseudo-absence data for modelling. However, in this study model quality was higher with null samples collected in the field. Next to species data the choice of landscape data is crucial for suitability modelling. Landscape data with high resolution and ecological relevance for the study species improve model reliability and quality for small elusive mammals like Muscardinus avellanarius. For large scale assessment of species distribution, models with low-detailed data are sufficient. For regional site-specific conservation issues like a conflict-free site for new wind turbines, high-detailed regional models are needed. Even though the overlap with optimally suitable habitat for M. avellanarius was low, the installation of wind plants can pose a threat due to habitat loss and fragmentation. To conclude, modellers should clearly state the purpose of their models and choose the according level of detail for species and environmental data. PMID:25781894

  4. Silvicolous on a small scale: possibilities and limitations of habitat suitability models for small, elusive mammals in conservation management and landscape planning.

    PubMed

    Becker, Nina I; Encarnação, Jorge A

    2015-01-01

    Species distribution and endangerment can be assessed by habitat-suitability modelling. This study addresses methodical aspects of habitat suitability modelling and includes an application example in actual species conservation and landscape planning. Models using species presence-absence data are preferable to presence-only models. In contrast to species presence data, absences are rarely recorded. Therefore, many studies generate pseudo-absence data for modelling. However, in this study model quality was higher with null samples collected in the field. Next to species data the choice of landscape data is crucial for suitability modelling. Landscape data with high resolution and ecological relevance for the study species improve model reliability and quality for small elusive mammals like Muscardinus avellanarius. For large scale assessment of species distribution, models with low-detailed data are sufficient. For regional site-specific conservation issues like a conflict-free site for new wind turbines, high-detailed regional models are needed. Even though the overlap with optimally suitable habitat for M. avellanarius was low, the installation of wind plants can pose a threat due to habitat loss and fragmentation. To conclude, modellers should clearly state the purpose of their models and choose the according level of detail for species and environmental data.

  5. Mapping of the distribution of Trypanosoma cruzi infection among small wild mammals in a conservation unit and its surroundings (Northeast-Brazil).

    PubMed

    Xavier, S C C; Vaz, V C; D'Andrea, P S; Herrera, L; Emperaire, L; Alves, J R; Fernandes, O; Ferreira, L F; Jansen, A M

    2007-06-01

    Maps are a useful tool that permits correlation of landscapes with hotspots of parasite transmission. Here, they were used as a tool for geovisualization to evaluate variables involved in the transmission of Trypanosoma cruzi among small wild mammals in an area endemic for Chagas disease, the "Serra da Capivara" National Park (PARNA) and its surroundings in Piauí State, Northeast Brazil. The implementation of a Geographical Information System (GIS) allowed the observation that a previously noted aggregated distribution of Triatoma sordida and Triatoma brasiliensis, T. cruzi prevalence and infection pattern of small wild mammals was directly or indirectly influenced by the local relief and human action. Small mammalian species diversity was higher in mesic refugia inside the park and in its buffer zone and lower in the disturbed area by anthropic activities. Didelphis albiventris was more abundant in the areas affected by human action. Thrichomys laurentius demonstrated to be an eclectic species and a competent reservoir of T. cruzi, being infected in all study areas. Small wild mammals infected with the TCII genotype of T. cruzi were localized only in the buffer zone of PARNA while TCI infected specimens were found in both areas, inside the PARNA and its buffer zone. The impact of biodiversity loss on the transmission cycle of T. cruzi in the wild environment was discussed.

  6. Small-mammal density estimation: A field comparison of grid-based vs. web-based density estimators

    USGS Publications Warehouse

    Parmenter, R.R.; Yates, Terry L.; Anderson, D.R.; Burnham, K.P.; Dunnum, J.L.; Franklin, A.B.; Friggens, M.T.; Lubow, B.C.; Miller, M.; Olson, G.S.; Parmenter, Cheryl A.; Pollard, J.; Rexstad, E.; Shenk, T.M.; Stanley, T.R.; White, Gary C.

    2003-01-01

    blind” test allowed us to evaluate the influence of expertise and experience in calculating density estimates in comparison to simply using default values in programs CAPTURE and DISTANCE. While the rodent sample sizes were considerably smaller than the recommended minimum for good model results, we found that several models performed well empirically, including the web-based uniform and half-normal models in program DISTANCE, and the grid-based models Mb and Mbh in program CAPTURE (with AÌ‚ adjusted by species-specific full mean maximum distance moved (MMDM) values). These models produced accurate DÌ‚ values (with 95% confidence intervals that included the true D values) and exhibited acceptable bias but poor precision. However, in linear regression analyses comparing each model's DÌ‚ values to the true D values over the range of observed test densities, only the web-based uniform model exhibited a regression slope near 1.0; all other models showed substantial slope deviations, indicating biased estimates at higher or lower density values. In addition, the grid-based DÌ‚ analyses using full MMDM values for WÌ‚ area adjustments required a number of theoretical assumptions of uncertain validity, and we therefore viewed their empirical successes with caution. Finally, density estimates from the independent analysts were highly variable, but estimates from web-based approaches had smaller mean square errors and better achieved confidence-interval coverage of D than did grid-based approaches. Our results support the contention that web-based approaches for density estimation of small-mammal populations are both theoretically and empirically superior to grid-based approaches, even when sample size is far less than often recommended. In view of the increasing need for standardized environmental measures for comparisons among ecosystems and through time, analytical models based on distance sampling appear to offer accurate density estimation approaches for research

  7. The uptake and effects of lead on small mammals and frogs at a trap and skeet range

    SciTech Connect

    Stansley, W.; Roscoe, D.E.

    1995-12-31

    This study was performed to evaluate the bioavailability and effects of lead in wildlife at a trap and skeet range. The total lead concentration in a composite soil sample (pellets removed) was 75,000 {micro}g/g dry weight. Mean tissue lead concentrations ({micro}g/g dry wt.) in while footed mice at the range (liver = 4.98, kidney = 34.9, femur = 245) were elevated (P < 0.01) 5 to 64-fold relative to concentrations in mice from a control area. Tissue lead concentrations in the only short tail shrew captured at the range (liver = 34.1, kidney = 1506, femur = 437) were elevated 35 to 1,038-fold. Femur lead concentrations in green frogs at the range (1,728 {micro}g/g) were elevated nearly 1,000-fold, and the lead concentration in a pooled kidney sample (96.2 {micro}g/g) was elevated 67-fold. There was significant depression of blood ALAD activity in mice (P = 0.0384) and depression of blood and liver ALAD activity in frogs (P<0.001). Hemoglobin concentrations were reduced 6.7% in mice (P = 0.0249), but hematocrit was not significantly affected in mice or frogs. Kidney:body weight ratios were similar in range and control mice. Intranuclear inclusions were present in the renal proximal tubular epithelium of two of the mice and the shrew that were captured at the range, and necrosis of the tubular epithelium was also evident in one of the mice, Soil ingestion may be a significant route of lead uptake in small mammals at the range. However, the tendency of lead to concentrate in the bones rather than in more digestible soft tissues may minimize food chain uptake of lead by predators, especially raptors that regurgitate undigestible material.

  8. Predicted Shifts in Small Mammal Distributions and Biodiversity in the Altered Future Environment of Alaska: An Open Access Data and Machine Learning Perspective

    PubMed Central

    Baltensperger, A. P.; Huettmann, F.

    2015-01-01

    Climate change is acting to reallocate biomes, shift the distribution of species, and alter community assemblages in Alaska. Predictions regarding how these changes will affect the biodiversity and interspecific relationships of small mammals are necessary to pro-actively inform conservation planning. We used a set of online occurrence records and machine learning methods to create bioclimatic envelope models for 17 species of small mammals (rodents and shrews) across Alaska. Models formed the basis for sets of species-specific distribution maps for 2010 and were projected forward using the IPCC (Intergovernmental Panel on Climate Change) A2 scenario to predict distributions of the same species for 2100. We found that distributions of cold-climate, northern, and interior small mammal species experienced large decreases in area while shifting northward, upward in elevation, and inland across the state. In contrast, many southern and continental species expanded throughout Alaska, and also moved down-slope and toward the coast. Statewide community assemblages remained constant for 15 of the 17 species, but distributional shifts resulted in novel species assemblages in several regions. Overall biodiversity patterns were similar for both time frames, but followed general species distribution movement trends. Biodiversity losses occurred in the Yukon-Kuskokwim Delta and Seward Peninsula while the Beaufort Coastal Plain and western Brooks Range experienced modest gains in species richness as distributions shifted to form novel assemblages. Quantitative species distribution and biodiversity change projections should help land managers to develop adaptive strategies for conserving dispersal corridors, small mammal biodiversity, and ecosystem functionality into the future. PMID:26207828

  9. Predicted Shifts in Small Mammal Distributions and Biodiversity in the Altered Future Environment of Alaska: An Open Access Data and Machine Learning Perspective.

    PubMed

    Baltensperger, A P; Huettmann, F

    2015-01-01

    Climate change is acting to reallocate biomes, shift the distribution of species, and alter community assemblages in Alaska. Predictions regarding how these changes will affect the biodiversity and interspecific relationships of small mammals are necessary to pro-actively inform conservation planning. We used a set of online occurrence records and machine learning methods to create bioclimatic envelope models for 17 species of small mammals (rodents and shrews) across Alaska. Models formed the basis for sets of species-specific distribution maps for 2010 and were projected forward using the IPCC (Intergovernmental Panel on Climate Change) A2 scenario to predict distributions of the same species for 2100. We found that distributions of cold-climate, northern, and interior small mammal species experienced large decreases in area while shifting northward, upward in elevation, and inland across the state. In contrast, many southern and continental species expanded throughout Alaska, and also moved down-slope and toward the coast. Statewide community assemblages remained constant for 15 of the 17 species, but distributional shifts resulted in novel species assemblages in several regions. Overall biodiversity patterns were similar for both time frames, but followed general species distribution movement trends. Biodiversity losses occurred in the Yukon-Kuskokwim Delta and Seward Peninsula while the Beaufort Coastal Plain and western Brooks Range experienced modest gains in species richness as distributions shifted to form novel assemblages. Quantitative species distribution and biodiversity change projections should help land managers to develop adaptive strategies for conserving dispersal corridors, small mammal biodiversity, and ecosystem functionality into the future.

  10. Contaminant Exposure in Terrestrial Vertebrates

    EPA Science Inventory

    Manuscript is a critical review of the state of the science for quantifying exposures of terrestrial wildlife species to chemical contamination. It describes the unique aspects of birds, mammals, reptiles, amphibians and threatened and endangered species. Fate and transport of ...

  11. Spatio-temporal variation in small mammal species richness, relative abundance and body mass reveal changes in a coastal wetland ecosystem in Ghana.

    PubMed

    Ofori, Benjamin Y; Attuquayefio, Daniel K; Owusu, Erasmus H; Musah, Yahaya; Ntiamoa-Baidu, Yaa

    2016-06-01

    Coastal wetlands in Ghana are under severe threat of anthropogenic drivers of habitat degradation and climate change, thereby increasing the need for assessment and monitoring to inform targeted and effective conservation of these ecosystems. Here, we assess small mammal species richness, relative abundance and body mass in three habitats at the Muni-Pomadze Ramsar site of Ghana, and compare these to baseline data gathered in 1997 to evaluate changes in the wetland ecosystem. Small mammals were live-trapped using Sherman collapsible and pitfall traps. We recorded 84 individuals of 10 species in 1485 trap-nights, whereas the baseline study recorded 45 individuals of seven species in 986 trap-nights. The overall trap-success was therefore greater in the present study (5.66 %) than the baseline study (4.56 %). The species richness increased from one to four in the forest, and from zero to eight in the thicket, but decreased from six to four in the grassland. The total number of individuals increased in all habitats, with the dominant species in the grassland shifting from Lemniscomys striatus to Mastomys erythroleucus. Three species, Malacomys edwardsi, Grammomys poensis and Praomys tullbergi are the first records for the Muni-Pomadze Ramsar site. Generally, the average body mass of individual species in the grassland was lower in the present study. The considerable changes in small mammal community structure suggest changes in the wetland ecosystem. The conservation implications of our findings are discussed.

  12. Paleoenvironmental reconstruction of the early Neolithic to middle Bronze Age Peña Larga rock shelter (Álava, Spain) from the small mammal record

    NASA Astrophysics Data System (ADS)

    Rofes, Juan; Zuluaga, Mari Cruz; Murelaga, Xabier; Fernández-Eraso, Javier; Bailon, Salvador; Iriarte, María José; Ortega, Luis Ángel; Alonso-Olazabal, Ainhoa

    2013-03-01

    The Peña Larga site, a rock shelter on the southern slopes of the Cantabrian cordillera (north Spain), is an archeological deposit covering nearly 4000 years, from the early Neolithic to the middle Bronze Age (Atlantic/Subboreal chronozones). It was used both as a household and as a stable, with a hiatus in the Chalcolithic when it was used as a collective sepulcher. Nearly twenty-eight thousand small vertebrate elements were recovered from its seven stratigraphic units, of which 2553 items were identified to the genus and/or species levels. The assemblage is composed of mammals, birds, reptiles, and amphibians. Of these, small mammals were used for paleoenvironmental reconstruction since they are very sensitive to climatic conditions, the sample sizes are large, and their preservation is good. Their distributions over time, measured in terms of relative abundance, serve as reliable proxies of habitat and climate change. The reconstruction of Peña Larga's past environments based on small mammals roughly coincides with the pollen and the amphibian/reptile records on the local scale, and with that of an ice core from Central Greenland on the global scale. This makes it a valuable tool for comparative purposes both in the regional and continental scales.

  13. The great dichotomy of the Solar System: Small terrestrial embryos and massive giant planet cores

    NASA Astrophysics Data System (ADS)

    Morbidelli, A.; Lambrechts, M.; Jacobson, S.; Bitsch, B.

    2015-09-01

    The basic structure of the Solar System is set by the presence of low-mass terrestrial planets in its inner part and giant planets in its outer part. This is the result of the formation of a system of multiple embryos with approximately the mass of Mars in the inner disk and of a few multi-Earth-mass cores in the outer disk, within the lifetime of the gaseous component of the protoplanetary disk. What was the origin of this dichotomy in the mass distribution of embryos/cores? We show in this paper that the classic processes of runaway and oligarchic growth from a disk of planetesimals cannot explain this dichotomy, even if the original surface density of solids increased at the snowline. Instead, the accretion of drifting pebbles by embryos and cores can explain the dichotomy, provided that some assumptions hold true. We propose that the mass-flow of pebbles is two-times lower and the characteristic size of the pebbles is approximately ten times smaller within the snowline than beyond the snowline (respectively at heliocentric distance r rice , where rice is the snowline heliocentric distance), due to ice sublimation and the splitting of icy pebbles into a collection of chondrule-size silicate grains. In this case, objects of original sub-lunar mass would grow at drastically different rates in the two regions of the disk. Within the snowline these bodies would reach approximately the mass of Mars while beyond the snowline they would grow to ∼ 20 Earth masses. The results may change quantitatively with changes to the assumed parameters, but the establishment of a clear dichotomy in the mass distribution of protoplanets appears robust provided that there is enough turbulence in the disk to prevent the sedimentation of the silicate grains into a very thin layer.

  14. Reconstruction of the Neanderthal and Modern Human landscape and climate from the Fumane cave sequence (Verona, Italy) using small-mammal assemblages

    NASA Astrophysics Data System (ADS)

    López-García, Juan Manuel; dalla Valle, Chiara; Cremaschi, Mauro; Peresani, Marco

    2015-11-01

    Fumane cave, located at an altitude of 350 m.a.s.l. in the Monti Lessini in the Veneto Pre-Alps, northeastern Italy, is a reference site for southern Europe for the study of the behaviour of Neanderthals and Anatomically Modern Humans (AMH) from Marine Isotope Stages 5 to 2 (MIS5-MIS2). It is one of the few well-dated and closely studied sites in the Italian Peninsula, with a finely layered sedimentary sequence from the Mousterian to Gravettian. In this paper we present for the first time a palaeoenvironmental and palaeoclimatic reconstruction of the MIS3 and MIS2 sequence based on the small mammal (insectivore, bat and rodent) assemblages. The environmental and climatic results, coupled with the radiocarbon dating together with previous studies on large mammals, birds and charcoal and other studies on small mammals and pollen for the same time-span in Italy, enable us clearly to identify distinct climatic periods within our data: Heinrich Event 5 in units A7 to A6, Greenland Interstadial 12 in units A5 + A6 to A4, Heinrich Event 4 in units A3 to A1, and Heinrich Event 3 in unit D1e. Finally, the study shows that Neanderthals and Anatomically Modern Humans were well adapted to the different climatic and environmental conditions of MIS3 at the foot of the Alps.

  15. Trypanosoma cruzi TcI and TcII transmission among wild carnivores, small mammals and dogs in a conservation unit and surrounding areas, Brazil.

    PubMed

    Rocha, Fabiana Lopes; Roque, André Luiz Rodrigues; Arrais, Ricardo Corassa; Santos, Jean Pierre; Lima, Valdirene dos Santos; Xavier, Samanta Cristina das Chagas; Cordeir-Estrela, Pedro; D'Andrea, Paulo Sérgio; Jansen, Ana Maria

    2013-02-01

    Aiming to better understand the ecological aspects of Trypanosoma cruzi transmission cycles, wild carnivores, small mammals and dogs were examined for T. cruzi infection in the Serra da Canastra National Park region, Brazil. Isolates were genotyped using mini-exon gene and PCR-RFLP (1f8 and H3) genomic targets. Trypanosoma cruzi transmission was well established in the area and occurred in both wild and peridomestic environments. Dog seroprevalence was 29·4% (63/214) and TcI and TcII genotypes, besides mixed infections were observed. Only TcI was detected in wild mammals. Marsupials displayed lower relative abundance, but a high prevalence of positive haemocultures (4/22), whereas rodents displayed positive haemocultures (9/113) mainly in the abundant Akodon montensis and Cerradomys subflavus species. The felid Leopardus pardalis was the only carnivore to display positive haemoculture and was captured in the same region where the small mammal prevalence of T. cruzi infection was high. Two canid species, Chrysocyon brachyurus and Cerdocyon thous, were serologically positive for T. cruzi infection (4/8 and 8/39, respectively), probably related to their capacity to exploit different ecological niches. Herein, dog infection not only signals T. cruzi transmission but also the genotypes present. Distinct transmission strategies of the T. cruzi genotypes are discussed.

  16. 77 FR 69797 - Small Takes of Marine Mammals Incidental to Specified Activities; Pile Driving in Port Townsend...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-21

    ... vicinity of the ferry terminal. Because direct pull and clamshell pile removal, and use of barges do not... we require WSF to monitor before, during, and after all ramp-ups of vibratory and impact pile driving.... Response: We disagree that WSF needs to monitor for marine mammals before, during, and after all...

  17. 76 FR 51947 - Small Takes of Marine Mammals Incidental to Specified Activities; Pile Driving in the Columbia...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-19

    ... devices, such as a bubble curtain, would be used during any impact hammering. In addition to pile... the sensitivity of the receptor (Richardson et al., 1995). Marine mammal reactions to sound may depend.... Jacobs and Terhune (2002) observed wild harbor seal reactions to high-frequency acoustic...

  18. Longitudinal differences in 15N between mothers and offspring during and after weaning in a small cooperative mammal, the meerkat (Suricata suricatta).

    PubMed

    Dalerum, Fredrik; Bennett, Nigel C; Clutton-Brock, Tim H

    2007-01-01

    Gestation and subsequent lactation are energetically costly life history events for mammalian females. We used longitudinal delta15N data from hair samples from offspring and their mothers to explore lactation patterns in a small cooperative mammal, the meerkat (Suricata suricatta). Lactation enriched hair from meerkat offspring in 15N compared with that of their mothers, and this enrichment gradually declined after weaning. Although the observed peak enrichment of approximately 1 per thousand was substantially below the predicted levels of trophic enrichment in capital versus income breeders, we suggest that our results reflect an income breeding tactic in this species. Our study supports the notion that delta15N analyses can be a useful tool to investigate lactation schedules in mammals. However, reliable conclusions from 15N data regarding the nutritional tactics of mammalian females during reproduction may be limited by our scant understanding of the effects of various physiological variables on isotope assimilation.

  19. Prevalence, Genetic Characterization, and 18S Small Subunit Ribosomal RNA Diversity of Trypanosoma rangeli in Triatomine and Mammal Hosts in Endemic Areas for Chagas Disease in Ecuador

    PubMed Central

    Ocaña-Mayorga, Sofia; Aguirre-Villacis, Fernanda; Pinto, C. Miguel; Vallejo, Gustavo A.

    2015-01-01

    Abstract Trypanosoma rangeli is a nonpathogenic parasite for humans; however, its medical importance relies in its similarity and overlapping distribution with Trypanosoma cruzi, causal agent of Chagas disease in the Americas. The genetic diversity of T. rangeli and its association with host species (triatomines and mammals) has been identified along Central and the South America; however, it has not included data of isolates from Ecuador. This study reports infection with T. rangeli in 18 genera of mammal hosts and five species of triatomines in three environments (domestic, peridomestic, and sylvatic). Higher infection rates were found in the sylvatic environment, in close association with Rhodnius ecuadoriensis. The results of this study extend the range of hosts infected with this parasite and the geographic range of the T. rangeli genotype KP1(−)/lineage C in South America. It was not possible to detect variation on T. rangeli from the central coastal region and southern Ecuador with the analysis of the small subunit ribosomal RNA (SSU-rRNA) gene, even though these areas are ecologically different and a phenotypic subdivision of R. ecuadoriensis has been found. R. ecuadoriensis is considered one of the most important vectors for Chagas disease transmission in Ecuador due to its wide distribution and adaptability to diverse environments. An extensive knowledge of the trypanosomes circulating in this species of triatomine, and associated mammal hosts, is important for delineating transmission dynamics and preventive measures in the endemic areas of Ecuador and Northern Peru. PMID:26645579

  20. Prevalence, Genetic Characterization, and 18S Small Subunit Ribosomal RNA Diversity of Trypanosoma rangeli in Triatomine and Mammal Hosts in Endemic Areas for Chagas Disease in Ecuador.

    PubMed

    Ocaña-Mayorga, Sofia; Aguirre-Villacis, Fernanda; Pinto, C Miguel; Vallejo, Gustavo A; Grijalva, Mario J

    2015-12-01

    Trypanosoma rangeli is a nonpathogenic parasite for humans; however, its medical importance relies in its similarity and overlapping distribution with Trypanosoma cruzi, causal agent of Chagas disease in the Americas. The genetic diversity of T. rangeli and its association with host species (triatomines and mammals) has been identified along Central and the South America; however, it has not included data of isolates from Ecuador. This study reports infection with T. rangeli in 18 genera of mammal hosts and five species of triatomines in three environments (domestic, peridomestic, and sylvatic). Higher infection rates were found in the sylvatic environment, in close association with Rhodnius ecuadoriensis. The results of this study extend the range of hosts infected with this parasite and the geographic range of the T. rangeli genotype KP1(-)/lineage C in South America. It was not possible to detect variation on T. rangeli from the central coastal region and southern Ecuador with the analysis of the small subunit ribosomal RNA (SSU-rRNA) gene, even though these areas are ecologically different and a phenotypic subdivision of R. ecuadoriensis has been found. R. ecuadoriensis is considered one of the most important vectors for Chagas disease transmission in Ecuador due to its wide distribution and adaptability to diverse environments. An extensive knowledge of the trypanosomes circulating in this species of triatomine, and associated mammal hosts, is important for delineating transmission dynamics and preventive measures in the endemic areas of Ecuador and Northern Peru.

  1. Cadmium accumulation in herbivorous and carnivorous small mammals: meta-analysis of field data and validation of the bioaccumulation model Optimal Modeling for Ecotoxicological Applications.

    PubMed

    Veltman, Karin; Huijbregts, Mark A J; Hamers, Timo; Wijnhoven, Sander; Hendriks, A Jan

    2007-07-01

    Environmental risk assessment procedures often use bioaccumulation as a criterion for hazard identification of a polluted location. Field studies regarding metal concentrations in food chains, however, have provided widely different information, because accumulation is shown to vary between the extremes of bioreduction and biomagnification. Bioaccumulation models provide insight regarding species-specific uptake and elimination kinetics of metals and assist in the interpretation of field data. Here, we use the bioaccumulation model OMEGA (Optimal Modeling for Ecotoxicological Applications) to estimate cadmium accumulation in herbivorous voles and carnivorous shrews. In addition to model validation, a meta-analysis of cadmium accumulation data is performed, because earlier studies generally have focused on relationships between cadmium concentrations in either specific tissues (kidney and liver) or whole-body concentrations and total soil levels. Additionally, we included the food-small mammal relationship. Our results show that cadmium whole-body concentrations are significantly related to cadmium levels in food items such as earthworms and plants. In addition, a significant relationship is found between cadmium accumulation in the liver and kidney of small mammals and total soil levels. Cadmium concentrations in shrews typically are an order of magnitude higher than metal levels in voles as a result of higher metal accumulation in earthworms compared to plants. Model predictions for both voles and shrews are in good agreement with field observations; deviations generally are within a factor of five. Small mammals prevent cadmium toxicity by binding this metal to metallothionein, which likely results in low elimination rates. Comparison with empirical elimination rates shows that rate constants of loss are accurately predicted assuming that cadmium is only released via growth dilution.

  2. Douglas-fir forests in the Cascade Mountains of Oregon and Washington: is the abundance of small mammals related to stand age and moisture?

    USGS Publications Warehouse

    Coen, P.S.; Bury, R.B.; Spies, T.A.

    1988-01-01

    Red tree voles (Arborimus longicaudus) were the only small mammal strongly associated with old-growth forests, whereas vagrant shrews (Sorex vagrans) were most abundant in young forests. Pacific marsh shrews (S. bendirii) were most abundant in wet old-growth forests, but abundance of this species in young (wet) forests needs further study. Clearcuts had a mammalian fauna distinct from young forest stands. Abundance of several species was correlated to habitat features unique to naturally regenerated forests, indicated an urgent need to study the long-term effects of forest management to nongame wildlife.

  3. Serological surveillance of scrub typhus, murine typhus, and leptospirosis in small mammals captured at Twin Bridges Training Area, Gyeonggi Province, Republic of Korea, 2005-2007.

    PubMed

    Sames, William J; Klein, Terry A; Kim, Heung-Chul; Gu, Se Hun; Kang, Hae-Ji; Shim, So-Hee; Ha, Si-Jung; Chong, Sung-Tae; Lee, In-Yong; Richards, Allen L; Yi, Suk-Hee; Song, Jin-Won

    2010-01-01

    Soldiers from the Republic of Korea and the United States conduct armistice military operations at Twin Bridges Training Area (TBTA) located near the demilitarized zone (DMZ) and are exposed to zoonotic disease pathogens that small mammals and their potentially disease-carrying ectoparasites transmit. TBTA is a 36 km2 rural training site with small villages and various forms of agriculture along its boundary. At TBTA, rodents, insectivores, and their ectoparasites are commonly found in association with unmanaged habitats of various densities of tall grasses, herbaceous plants, shrubs, briars, and crawling vegetation. Rodents and insectivores were collected during the winter (November-December 2005 and December 2006) and early spring (March 2007), and serologically tested for the presence of scrub typhus, murine typhus, and leptospirosis antibodies. Of the six species of small mammals collected, Apodemus agrarius, the common striped field mouse and known reservoir of scrub typhus, was the most frequently collected (96.1%), followed by Crocidura lasiura (2.5%), Micromys minutus (0.5%), Myodes regulus (0.5%), Mus musculus (0.3%), and Rattus rattus (0.1%). A. agrarius (56.1%), M. musculus (66.7%), M. minutus (25%), and R. rattus (100%) were positive for scrub typhus antibodies. Only A. agrarius (14.7%) and C. lasiura (4.5%) were positive for murine typhus antibodies, whereas only A. agrarius (1.5%) was seropositive for leptospirosis. Seroprevalence rates of scrub typhus and murine typhus based on weight and sex of A. agrarius are presented.

  4. The Oldest Caseid Synapsid from the Late Pennsylvanian of Kansas, and the Evolution of Herbivory in Terrestrial Vertebrates

    PubMed Central

    Reisz, Robert R.; Fröbisch, Jörg

    2014-01-01

    The origin and early evolution of amniotes (fully terrestrial vertebrates) led to major changes in the structure and hierarchy of terrestrial ecosystems. The first appearance of herbivores played a pivotal role in this transformation. After an early bifurcation into Reptilia and Synapsida (including mammals) 315 Ma, synapsids dominated Paleozoic terrestrial vertebrate communities, with the herbivorous caseids representing the largest vertebrates on land. Eocasea martini gen. et sp. nov., a small carnivorous caseid from the Late Carboniferous, extends significantly the fossil record of Caseidae, and permits the first clade-based study of the origin and initial evolution of herbivory in terrestrial tetrapods. Our results demonstrate for the first time that large caseid herbivores evolved from small, non-herbivorous caseids. This pattern is mirrored by three other clades, documenting multiple, independent, but temporally staggered origins of herbivory and increase in body size among early terrestrial tetrapods, leading to patterns consistent with modern terrestrial ecosystem. PMID:24739998

  5. The oldest caseid synapsid from the Late Pennsylvanian of Kansas, and the evolution of herbivory in terrestrial vertebrates.

    PubMed

    Reisz, Robert R; Fröbisch, Jörg

    2014-01-01

    The origin and early evolution of amniotes (fully terrestrial vertebrates) led to major changes in the structure and hierarchy of terrestrial ecosystems. The first appearance of herbivores played a pivotal role in this transformation. After an early bifurcation into Reptilia and Synapsida (including mammals) 315 Ma, synapsids dominated Paleozoic terrestrial vertebrate communities, with the herbivorous caseids representing the largest vertebrates on land. Eocasea martini gen. et sp. nov., a small carnivorous caseid from the Late Carboniferous, extends significantly the fossil record of Caseidae, and permits the first clade-based study of the origin and initial evolution of herbivory in terrestrial tetrapods. Our results demonstrate for the first time that large caseid herbivores evolved from small, non-herbivorous caseids. This pattern is mirrored by three other clades, documenting multiple, independent, but temporally staggered origins of herbivory and increase in body size among early terrestrial tetrapods, leading to patterns consistent with modern terrestrial ecosystem.

  6. Diversity and Impacts of Mining on the Non-Volant Small Mammal Communities of Two Vegetation Types in the Brazilian Amazon.

    PubMed

    Ardente, Natália Carneiro; Ferreguetti, Átilla Colombo; Gettinger, Donald; Leal, Pricila; Mendes-Oliveira, Ana Cristina; Martins-Hatano, Fernanda; Bergallo, Helena Godoy

    2016-01-01

    The Carajás National Forest contains some of the largest iron ore deposits in the world. The majority of the minerals are found below a plant community known as Savana Metalófila, or "Canga", which represents only 3% of the landscape within the Carajás National Forest (CNF). The aim of our study was to understand the diversity of community of non-volant small mammals in the two predominant vegetation types: Ombrophilous Forest and Canga, and to examine how mining impacts these communities. Sampling was conducted from January 2010 to August 2011 in 11 sampling sites divided by the total area of Canga and 12 sampling sites in the forest, totalizing 23 sites. Of these, 12 sites (Canga and Forest) were considered impacted areas located close to the mine (< 900 meters) and 11 sites (Canga and Forest), serving as controls, which were at least 7,000 meters from the mine. We recorded 28 species, 11 from the Order Didelphimorphia and 17 from the Order Rodentia. The two forest types shared 68.42% of the species found in the CNF. A gradient analysis (Non-metric multidimensional scaling) revealed that the first axis clearly separated the non-flying small mammal communities by vegetation type. Occupancy models showed that the detectability of species was affected by the distance from the mining activities. Of all the small mammals analyzed, 10 species were positively affected by the distance from mining in areas impacted (e.g. more likely to be detected farther from mining areas) and detectability was lower in impacted areas. However, three species were negatively affected by the distance from mining, with higher detectability in the impacted areas, and seven species showed no effect of their proximity to mining operations. To date, there are no studies in Brazil about the impact of mining on mammals or other vertebrates. This study reveals that the effect of mining may go beyond the forest destruction caused by the opening of the mining pits, but also may negatively affect

  7. Diversity and Impacts of Mining on the Non-Volant Small Mammal Communities of Two Vegetation Types in the Brazilian Amazon

    PubMed Central

    Ardente, Natália Carneiro; Ferreguetti, Átilla Colombo; Gettinger, Donald; Leal, Pricila; Mendes-Oliveira, Ana Cristina; Martins-Hatano, Fernanda; Bergallo, Helena Godoy

    2016-01-01

    The Carajás National Forest contains some of the largest iron ore deposits in the world. The majority of the minerals are found below a plant community known as Savana Metalófila, or “Canga”, which represents only 3% of the landscape within the Carajás National Forest (CNF). The aim of our study was to understand the diversity of community of non-volant small mammals in the two predominant vegetation types: Ombrophilous Forest and Canga, and to examine how mining impacts these communities. Sampling was conducted from January 2010 to August 2011 in 11 sampling sites divided by the total area of Canga and 12 sampling sites in the forest, totalizing 23 sites. Of these, 12 sites (Canga and Forest) were considered impacted areas located close to the mine (<< 900 meters) and 11 sites (Canga and Forest), serving as controls, which were at least 7,000 meters from the mine. We recorded 28 species, 11 from the Order Didelphimorphia and 17 from the Order Rodentia. The two forest types shared 68.42% of the species found in the CNF. A gradient analysis (Non-metric multidimensional scaling) revealed that the first axis clearly separated the non-flying small mammal communities by vegetation type. Occupancy models showed that the detectability of species was affected by the distance from the mining activities. Of all the small mammals analyzed, 10 species were positively affected by the distance from mining in areas impacted (e.g. more likely to be detected farther from mining areas) and detectability was lower in impacted areas. However, three species were negatively affected by the distance from mining, with higher detectability in the impacted areas, and seven species showed no effect of their proximity to mining operations. To date, there are no studies in Brazil about the impact of mining on mammals or other vertebrates. This study reveals that the effect of mining may go beyond the forest destruction caused by the opening of the mining pits, but also may negatively

  8. Edge effects and landscape matrix use by a small mammal community in fragments of semideciduous submontane forest in Mato Grosso, Brazil.

    PubMed

    Santos-Filho, M; Silva, D J da; Sanaiotti, T M

    2008-11-01

    A community of small mammals was studied in seasonal semideciduous submontane forest in the state of Mato Grosso, Brazil. This study evaluated the use of edge and matrix pasture, by different small mammal species. Overall, 31 areas were studied, with a total sampling effort of 33,800 trap x nights. Only seven of the 25 species captured in the study sites were able to use the pasture matrix; we classified these species as generalists. Fourteen species were found to be intermediate in habits, being able to use forest edges. We found only four species habitat specialists, occurring only on transect lines in the interior of the fragment, at least 150 m from the edge. Transects located in the pasture matrix and 50 m from the edge had significantly lower species richness and abundance than transects located in the fragment edge or in the interior of the fragment. All transects located within the fragment had similar species richness and abundance, but transects located 50 m from the edge had slightly lower, but non-significant, species richness than transects located 100 m apart from edges. Rarefaction curves demonstrated that only medium-sized fragments (100-300 ha) reached an asymptote of species accumulation. The other areas require further sampling, or more sampling transect, before species accumulation curves stabilize, due to a continued increase in species number.

  9. Holocene environmental change in the eastern Snake River Plain of Idaho, USA, as inferred from stable isotope analyses of small mammals

    NASA Astrophysics Data System (ADS)

    Commendador, Amy S.; Finney, Bruce P.

    2016-05-01

    Previous research on the small mammal population recovered from archeological excavations at the Wasden Site in southeastern Idaho suggests that changing frequency distributions through time represent a shift in climate during the early Holocene from a cooler, wetter regime to a warmer, drier one. This conclusion was re-evaluated using stable carbon and nitrogen isotope analyses of bone collagen from the three species of small mammals examined in the earlier studies: pocket gophers (Thomomys talpoides), pygmy rabbits (Brachylagus idahoensis), and ground squirrels (Spermophilus townsendii). Resulting carbon and nitrogen isotopic values are consistent with known differences in feeding ecology, suggesting high fidelity as proxies for past vegetation (and thus climate) regimes. Patterns of 15N enrichment and increased representation of C4-CAM vegetation observed in the pocket gophers, and to a lesser extent ground squirrels, suggests increasing warmth and/or aridity from the early Holocene until ∼7000 cal yr BP, thus supporting previous hypotheses of climate change on the eastern Snake River Plain. The results highlight the potential contribution of such studies for archeological research by providing additional proxies for environmental conditions that bear on paleoecological adaptations to climatic change, including past human use and occupation of the region.

  10. Differentiation of flea communities infesting small mammals across selected habitats of the Baltic coast, central lowlands, and southern mountains of Poland.

    PubMed

    Kowalski, Krzysztof; Eichert, Urszula; Bogdziewicz, Michał; Rychlik, Leszek

    2014-05-01

    Only a few studies comparing flea composition on the coast and in the mountains have been conducted. We investigated differences in flea communities infesting small mammals in selected habitats in northern, central, and southern Poland. We predicted (1) a greater number of flea species in the southeastern Poland and a lower number in the north, (2) a greater number of flea species in fertile and wet habitats than in poor and arid habitats, and (3) a low similarity of flea species between flea communities in western and eastern Poland. We found a negative effect of increasing latitude on flea species richness. We suppose that the mountains providing a variety of environments and the limits of the geographic ranges of several flea subspecies in southeastern Poland result in a higher number of flea species. There was a positive effect of increasing wetness of habitat on flea species richness. We found a high diversity in flea species composition between western and eastern Poland (beta diversity = 11) and between central and eastern Poland (beta diversity = 12). Re-colonization of Poland by small mammals and their ectoparasites from different (western and eastern) refugees can affect on this high diversity of flea species.

  11. Taphonomy and palaeoecology of the late Pleistocene to middle Holocene small mammal succession of El Harhoura 2 cave (Rabat-Témara, Morocco).

    PubMed

    Stoetzel, Emmanuelle; Marion, Lucile; Nespoulet, Roland; El Hajraoui, Mohammed Abdeljalil; Denys, Christiane

    2011-01-01

    The relationship between local and global climatic variations and the origin and dispersal of Homo sapiens in Africa is complex, and North Africa may have played a major role in these events. In Morocco, very few studies are specifically dedicated to small fossil vertebrates, and neither taphonomic nor palaeoecological studies have been undertaken on these taxa, particularly in archaeological contexts. The late Pleistocene to middle Holocene succession of El Harhoura 2 cave, situated in the region of Témara, yields an exceptionally rich small vertebrate assemblage. We present the results of a first systematic, taphonomic, and palaeoecological study of the small mammals from Levels 1 to 8 of El Harhoura 2. The absence of bone sorting and polishing, as well as the presence of significant traces of digestion indicate that the small mammal bones were accumulated in the cave by predators and that no water transport occurred. Other traces observed on the surface of bones consist mainly of root marks and black traces (micro-organisms or more probably manganese) which affected the majority of the material. The percentage of fragmentation is very high in all stratigraphic levels, and the post-depositional breakage (geologic and anthropogenic phenomena) obscure the original breakage patterns of bones by predators. According to the ecology of the different species present in the levels of El Harhoura 2, and by taking into account possible biases highlighted by the taphonomic analysis, we reconstruct the palaeoenvironmental evolution in the region. For quantitative reconstructions we used two indices: the Taxonomic Habitat Index (THI) and the Gerbillinae/Murinae ratio. Late Pleistocene accumulations were characterised by a succession of humid (Levels 3, 4a, 6, and 8) and arid (Levels 2?, 5, and 7) periods, with more or less open landscapes, ending in an ultimate humid and wooded period during the middle Holocene (Level 1). We discuss particular limits of our results and

  12. Osmoregulation in marine mammals

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.

    2001-01-01

    Osmoregulation in marine mammals has been investigated for over a century; however, a review of recent advances in our understanding of water and electrolyte balance and of renal function in marine mammals is warranted. The following topics are discussed: (i) kidney structure and urine concentrating ability, (ii) sources of water, (iii) the effects of feeding, fasting and diving, (iv) the renal responses to infusions of varying salinity and (v) hormonal regulation. The kidneys of pinnipeds and cetaceans are reniculate in structure, unlike those of terrestrial mammals (except bears), but this difference does not confer any greater concentrating ability. Pinnipeds, cetaceans, manatees and sea otters can concentrate their urine above the concentration of sea water, but only pinnipeds and otters have been shown to produce urine concentrations of Na+ and Cl- that are similar to those in sea water. This could afford them the capacity to drink sea water and not lose fresh water. However, with few exceptions, drinking is not a common behavior in pinnipeds and cetaceans. Water balance is maintained in these animals via metabolic and dietary water, while incidental ingestion and dietary salt may help maintain electrolyte homeostasis. Unlike most other aquatic mammals, sea otters commonly drink sea water and manatees frequently drink fresh water. Among the various taxonomic groups of marine mammals, the sensitivity of the renin-angiotensin-aldosterone system appears to be influenced by the availability of Na+. The antidiuretic role of vasopressin remains inconclusive in marine mammals, while the natriuretic function of atrial natriuretic peptide has yet to be examined. Ideas on the direction of future studies are presented.

  13. Arctic terrestrial ecosystem contamination.

    PubMed

    Thomas, D J; Tracey, B; Marshall, H; Norstrom, R J

    1992-07-15

    Limited data have been collected on the presence of contaminants in the Arctic terrestrial ecosystem, with the exception of radioactive fallout from atmospheric weapons testing. Although southern and temperate biological systems have largely cleansed themselves of radioactive fallout deposited during the 1950s and 1960s, Arctic environments have not. Lichens accumulate radioactivity more than many other plants because of their large surface area and long life span; the presence and persistence of radioisotopes in the Arctic is of concern because of the lichen----reindeer----human ecosystem. Effective biological half-life of cesium 137 is reckoned to be substantially less than its physical half-life. The database on organochlorines in Canadian Arctic terrestrial mammals and birds is very limited, but indications are that the air/plant/animal contaminant pathway is the major route of these compounds into the terrestrial food chain. For terrestrial herbivores, the most abundant organochlorine is usually hexachlorobenzene followed by hexachlorocyclohexane isomers. PCB accumulation favours the hexachlorobiphenyl, pentachlorobiphenyl and heptachlorobiphenyl homologous series. The concentrations of the various classes of organochlorine compounds are substantially lower in terrestrial herbivore tissues than in marine mammal tissues. PCBs and DDT are the most abundant residues in peregrine falcons (a terrestrial carnivore) reaching average levels of 9.2 and 10.4 micrograms.g-1, respectively, more than 10 times higher than other organochlorines and higher than in marine mammals, including the polar bear. Contaminants from local sources include metals from mining activities, hydrocarbons and waste drilling fluids from oil and gas exploration and production, wastes from DEW line sites, naturally occurring radionuclides associated with uranium mineralization, and smoke containing SO2 and H2SO4 aerosol from the Smoking Hills at Cape Bathurst, N.W.T.

  14. Antimicrobial resistance in faecal Escherichia coli isolates from farmed red deer and wild small mammals. Detection of a multiresistant E. coli producing extended-spectrum beta-lactamase.

    PubMed

    Alonso, C A; González-Barrio, D; Tenorio, Carmen; Ruiz-Fons, F; Torres, C

    2016-04-01

    Eighty-nine Escherichia coli isolates recovered from faeces of red deer and small mammals, cohabiting the same area, were analyzed to determine the prevalence and mechanisms of antimicrobial resistance and molecular typing. Antimicrobial resistance was detected in 6.7% of isolates, with resistances to tetracycline and quinolones being the most common. An E. coli strain carrying blaCTX-M-1 as well as other antibiotic resistant genes included in an unusual class 1 integron (Intl1-dfrA16-blaPSE-1-aadA2-cmlA1-aadA1-qacH-IS440-sul3-orf1-mef(B)Δ-IS26) was isolated from a deer. The blaCTX-M-1 gene was transferred by conjugation and transconjugants also acquired an IncN plasmid. This strain was typed as ST224, which seems to be well adapted to both clinical and environmental settings. The phylogenetic distribution of the 89 strains varied depending on the animal host. This work reveals low antimicrobial resistance levels among faecal E. coli from wild mammals, which reflects a lower selective pressure affecting these bacteria, compared to livestock. However, it is remarkable the detection of a multi-resistant ESBL-E. coli with an integron carrying clinically relevant antibiotic-resistance genes, which can contribute to the dissemination of resistance determinants among different ecosystems.

  15. Influence of continental history on the ecological specialization and macroevolutionary processes in the mammalian assemblage of South America: Differences between small and large mammals

    PubMed Central

    2008-01-01

    Background This paper tests Vrba's resource-use hypothesis, which predicts that generalist species have lower specialization and extinction rates than specialists, using the 879 species of South American mammals. We tested several predictions about this hypothesis using the biomic specialization index (BSI) for each species, which is based on its geographical range within different climate-zones. The four predictions tested are: (1) there is a high frequency of species restricted to a single biome, which henceforth are referred to as stenobiomic species, (2) certain clades are more stenobiomic than others, (3) there is a higher proportion of biomic specialists in biomes that underwent through major expansion-contraction alternation due to the glacial-interglacial cycles, (4) certain combinations of inhabited biomes occur more frequently among species than do others. Results Our results are consistent with these predictions. (1) We found that 42 % of the species inhabit only one biome. (2) There are more generalists among species of Carnivora than in clades of herbivores. However, Artiodactyla, shows a distribution along the specialization gradient different from the one expected. (3) Biomic specialists are predominant in tropical rainforest and desert biomes. Nevertheless, we found some differences between small and large mammals in relation to these results. Stenobiomic species of micromammalian clades are more abundant in most biomes than expected by chance, while in the case of macromammalian clades stenobiomic species are more frequent than expected in tropical rainforest, tropical deciduous woodland and desert biomes only. (4) The most frequent combinations of inhabited biomes among the South American mammals are those with few biomes, i.e., the ones that suffered a higher rate of vicariance due to climatic cycles. Conclusion Our results agree with the resource-use hypothesis and, therefore, with a major role of the past climatic changes as drivers of

  16. High muscle mitochondrial volume and aerobic capacity in a small marsupial (Sminthopsis crassicaudata) reveals flexible links between energy-use levels in mammals.

    PubMed

    Dawson, Terence J; Webster, Koa N; Lee, Enhua; Buttemer, William A

    2013-04-01

    We investigated the muscle structure-function relationships that underlie the aerobic capacity of an insectivorous, small (~15 g) marsupial, Sminthopsis crassicaudata (Family: Dasyuridae), to obtain further insight into energy use patterns in marsupials relative to those in placentals, their sister clade within the Theria (advanced mammals). Disparate hopping marsupials (Suborder Macropodiformes), a kangaroo (Macropus rufus) and a rat-kangaroo (Bettongia penicillata), show aerobic capabilities as high as those of 'athletic' placentals. Equivalent muscle mitochondrial volumes and cardiovascular features support these capabilities. We examined S. crassicaudata to determine whether highly developed aerobic capabilities occur elsewhere in marsupials, rather than being restricted to the more recently evolved Macropodiformes. This was the case. Treadmill-trained S. crassicaudata attained a maximal aerobic metabolic rate ( or MMR) of 272 ml O2 min(-1) kg(-1) (N=8), similar to that reported for a small (~20 g), 'athletic' placental, Apodemus sylvaticus, 264 ml O2 min(-1) kg(-1). Hopping marsupials have comparable aerobic levels when body mass variation is considered. Sminthopsis crassicaudata has a basal metabolic rate (BMR) about 75% of placental values but it has a notably large factorial aerobic scope (fAS) of 13; elevated fAS also features in hopping marsupials. The of S. crassicaudata was supported by an elevated total muscle mitochondrial volume, which was largely achieved through high muscle mitochondrial volume densities, Vv(mt,f), the mean value being 14.0±1.33%. These data were considered in relation to energy use levels in mammals, particularly field metabolic rate (FMR). BMR is consistently lower in marsupials, but this is balanced by a high fAS, such that marsupial MMR matches that of placentals. However, FMR shows different mass relationships in the two clades, with the FMR of small (<125 g) marsupials, such as S. crassicaudata, being higher than that in

  17. Heinrich Event 4 characterized by terrestrial proxies in southwestern Europe

    NASA Astrophysics Data System (ADS)

    López-García, J. M.; Blain, H.-A.; Bennàsar, M.; Sanz, M.; Daura, J.

    2013-02-01

    Heinrich Event 4 (H4) is well documented in the North Atlantic Ocean as a cooling event that occurred between 39 000 and 40 000 yr BP. Deep-sea cores around the Iberian Peninsula coastline have been analysed to characterize the H4 event, but there are no data on the terrestrial response to this event. Here we present for the first time an analysis of terrestrial proxies for characterizing the H4 event, using the small-vertebrate assemblage (comprising small mammals, squamates and amphibians) from Terrassa Riera dels Canyars, an archaeo-palaeontological deposit located on the seaboard of the northeastern Iberian Peninsula. This assemblage shows that the H4 event is characterized in northeastern Iberia by harsher and drier terrestrial conditions than today. Our results were compared with other proxies such as pollen, charcoal, phytolith, avifauna and large-mammal data available for this site, as well as with the general H4 event fluctuations and with other sites where H4 and the previous and subsequent Heinrich events (H5 and H3) have been detected in the Mediterranean and Atlantic regions of the Iberian Peninsula. We conclude that the terrestrial proxies follow the same patterns as the climatic and environmental conditions detected by the deep-sea cores at the Iberian margins.

  18. Heinrich event 4 characterized by terrestrial proxies in southwestern Europe

    NASA Astrophysics Data System (ADS)

    López-García, J. M.; Blain, H.-A.; Bennàsar, M.; Sanz, M.; Daura, J.

    2013-05-01

    Heinrich event 4 (H4) is well documented in the North Atlantic Ocean as a cooling event that occurred between 39 and 40 Ka. Deep-sea cores around the Iberian Peninsula coastline have been analysed to characterize the H4 event, but there are no data on the terrestrial response to this event. Here we present for the first time an analysis of terrestrial proxies for characterizing the H4 event, using the small-vertebrate assemblage (comprising small mammals, squamates and amphibians) from Terrassa Riera dels Canyars, an archaeo-palaeontological deposit located on the seaboard of the northeastern Iberian Peninsula. This assemblage shows that the H4 event is characterized in northeastern Iberia by harsher and drier terrestrial conditions than today. Our results were compared with other proxies such as pollen, charcoal, phytolith, avifauna and large-mammal data available for this site, as well as with the general H4 event fluctuations and with other sites where H4 and the previous and subsequent Heinrich events (H5 and H3) have been detected in the Mediterranean and Atlantic regions of the Iberian Peninsula. We conclude that the terrestrial proxies follow the same patterns as the climatic and environmental conditions detected by the deep-sea cores at the Iberian margins.

  19. Prevalence of Leptospira spp. in various species of small mammals caught in an inner-city area in Switzerland.

    PubMed Central

    Adler, H.; Vonstein, S.; Deplazes, P.; Stieger, C.; Frei, R.

    2002-01-01

    In order to establish the leptospira carrier rate of small animals in an urban environment, small rodents and shrews were captured in the city of Zurich, Switzerland. Kidney specimens of 190 animals were examined using a leptospira specific PCR assay. Leptospiral DNA was amplified in kidneys of 12.6% of the animals. PMID:11895085

  20. Ecology, distribution, and predictive occurrence modeling of Palmers chipmunk (Tamias palmeri): a high-elevation small mammal endemic to the Spring Mountains in southern Nevada, USA

    USGS Publications Warehouse

    Lowrey, Chris E.; Longshore, Kathleen; Riddle, Brett R.; Mantooth, Stacy

    2016-01-01

    Although montane sky islands surrounded by desert scrub and shrub steppe comprise a large part of the biological diversity of the Basin and Range Province of southwestern North America, comprehensive ecological and population demographic studies for high-elevation small mammals within these areas are rare. Here, we examine the ecology and population parameters of the Palmer’s chipmunk (Tamias palmeri) in the Spring Mountains of southern Nevada, and present a predictive GIS-based distribution and probability of occurrence model at both home range and geographic spatial scales. Logistic regression analyses and Akaike Information Criterion model selection found variables of forest type, slope, and distance to water sources as predictive of chipmunk occurrence at the geographic scale. At the home range scale, increasing population density, decreasing overstory canopy cover, and decreasing understory canopy cover contributed to increased survival rates.

  1. First Description of the Nymph and Larva of Dermacentor raskemensis (Acari: Ixodidae), Parasites of Pikas and Other Small Mammals in Central Asia

    PubMed Central

    Apanaskevich, Dmitry A.

    2014-01-01

    Dermacentor raskemensis Pomerantzev, 1946 is one of the rare Asian species in this genus. The immature stages of this species have never been described. Reexamination of D. raskemensis holdings stored in the United States National Tick Collection revealed a collection lot containing reared nymphs and larvae of this species. This collection made it possible for us to find numerous nymphs and larvae of D. raskemensis among previously unidentified material collected in the field. Both immature stages of D. raskemensis are described here for the first time. Nymphs of D. raskemensis can be distinguished from those of other Dermacentor species in the region by small spiracular plate, relatively short and obtuse lateral projections of basis capituli dorsally, relatively short spurs on coxa I and the internal spur is characteristically very broadly rounded at its apex, and very small spur on coxa IV, whereas larvae of D. raskemensis can be distinguished from other Dermacentor by relatively short and obtuse lateral projections of basis capituli, ≈6 denticles in the median files on hypostome, and relatively short, broad, and rounded spur on coxa I. The nymphs and larvae of D. raskemensis studied originate from Afghanistan, India, Iran, and Pakistan, where they were collected from pikas and other small mammals. PMID:24180099

  2. First description of the nymph and larva of Dermacentor raskemensis (Acari: Ixodidae), parasites of pikas and other small mammals in Central Asia.

    PubMed

    Apanaskevich, Dmitry A

    2013-09-01

    Dermacentor raskemensis Pomerantzev, 1946 is one of the rare Asian species in this genus. The immature stages of this species have never been described. Reexamination of D. raskemensis holdings stored in the United States National Tick Collection revealed a collection lot containing reared nymphs and larvae of this species. This collection made it possible for us to find numerous nymphs and larvae of D. raskemensis among previously unidentified material collected in the field. Both immature stages of D. raskemensis are described here for the first time. Nymphs of D. raskemensis can be distinguished from those of other Dermacentor species in the region by small spiracular plate, relatively short and obtuse lateral projections of basis capituli dorsally, relatively short spurs on coxa I and the internal spur is characteristically very broadly rounded at its apex, and very small spur on coxa IV, whereas larvae of D. raskemensis can be distinguished from other Dermacentor by relatively short and obtuse lateral projections of basis capituli, approximately 6 denticles in the median files on hypostome, and relatively short, broad, and rounded spur on coxa I. The nymphs and larvae of D. raskemensis studied originate from Afghanistan, India, Iran, and Pakistan, where they were collected from pikas and other small mammals.

  3. Small global effect on terrestrial net primary production due to increased fossil fuel aerosol emissions from East Asia since the turn of the century.

    PubMed

    O'Sullivan, M; Rap, A; Reddington, C L; Spracklen, D V; Gloor, M; Buermann, W

    2016-08-16

    The global terrestrial carbon sink has increased since the start of this century at a time of growing carbon emissions from fossil fuel burning. Here we test the hypothesis that increases in atmospheric aerosols from fossil fuel burning enhanced the diffuse light fraction and the efficiency of plant carbon uptake. Using a combination of models, we estimate that at global scale changes in light regimes from fossil fuel aerosol emissions had only a small negative effect on the increase in terrestrial net primary production over the period 1998-2010. Hereby, the substantial increases in fossil fuel aerosol emissions and plant carbon uptake over East Asia were effectively canceled by opposing trends across Europe and North America. This suggests that if the recent increase in the land carbon sink would be causally linked to fossil fuel emissions, it is unlikely via the effect of aerosols but due to other factors such as nitrogen deposition or nitrogen-carbon interactions.

  4. Small global effect on terrestrial net primary production due to increased fossil fuel aerosol emissions from East Asia since the turn of the century

    NASA Astrophysics Data System (ADS)

    O'Sullivan, M.; Rap, A.; Reddington, C. L.; Spracklen, D. V.; Gloor, M.; Buermann, W.

    2016-08-01

    The global terrestrial carbon sink has increased since the start of this century at a time of growing carbon emissions from fossil fuel burning. Here we test the hypothesis that increases in atmospheric aerosols from fossil fuel burning enhanced the diffuse light fraction and the efficiency of plant carbon uptake. Using a combination of models, we estimate that at global scale changes in light regimes from fossil fuel aerosol emissions had only a small negative effect on the increase in terrestrial net primary production over the period 1998-2010. Hereby, the substantial increases in fossil fuel aerosol emissions and plant carbon uptake over East Asia were effectively canceled by opposing trends across Europe and North America. This suggests that if the recent increase in the land carbon sink would be causally linked to fossil fuel emissions, it is unlikely via the effect of aerosols but due to other factors such as nitrogen deposition or nitrogen-carbon interactions.

  5. Small global effect on terrestrial net primary production due to increased fossil fuel aerosol emissions from East Asia since the turn of the century

    PubMed Central

    Rap, A.; Reddington, C. L.; Spracklen, D. V.; Gloor, M.; Buermann, W.

    2016-01-01

    Abstract The global terrestrial carbon sink has increased since the start of this century at a time of growing carbon emissions from fossil fuel burning. Here we test the hypothesis that increases in atmospheric aerosols from fossil fuel burning enhanced the diffuse light fraction and the efficiency of plant carbon uptake. Using a combination of models, we estimate that at global scale changes in light regimes from fossil fuel aerosol emissions had only a small negative effect on the increase in terrestrial net primary production over the period 1998–2010. Hereby, the substantial increases in fossil fuel aerosol emissions and plant carbon uptake over East Asia were effectively canceled by opposing trends across Europe and North America. This suggests that if the recent increase in the land carbon sink would be causally linked to fossil fuel emissions, it is unlikely via the effect of aerosols but due to other factors such as nitrogen deposition or nitrogen‐carbon interactions. PMID:27773953

  6. 76 FR 66274 - Small Takes of Marine Mammals Incidental to Specified Activities; Pier 36/Brannan Street Wharf...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-26

    ..., gray whale, harbor porpoise, humpback whale (Megaptera noveangliae), and sea otter (Enhydra lutris... present in the project vicinity during pile driving. Sea otters are managed by the United States Fish and... take, by Level B harassment, of small numbers of Pacific harbor seals (Phoca vitulina), California...

  7. Serosurveillance of scrub typhus in small mammals collected from military training sites near the DMZ, Northern Gyeonggi-do, Korea, and analysis of the relative abundance of chiggers from mammals examined.

    PubMed

    Kim, Heung Chul; Lee, In Yong; Chong, Sung Tae; Richards, Allen L; Gu, Se Hun; Song, Jin-Won; Lee, John S; Klein, Terry A

    2010-09-01

    Comprehensive quarterly serosurveillance on scrub typhus in small mammals collected from military training sites located near the Demilitarized Zone (DMZ), northern Gyeonggi-do (Province), ROK was conducted to determine the potential rodent-borne and associated ectoparasite disease risks to military personnel. A total of 1,196 rodents and insectivores representing 8 species, Apodemus agrarius (87.3%, n = 1,044), Mus musculus (5.4%, n = 65), Crocidura lasiura (3.3%, n = 40), Microtus fortis (2.6%, n = 31), Micromys minutus (0.3%, n = 4), Tscherskia triton (0.3%, n = 4), Rattus norvegicus (0.3%, n = 4), and Myodes regulus (0.3%, n = 4) were assayed for the presence of antibodies to Orientia tsutsugamushi. O. tsutsugamushi antibodies were detected in 6 of 8 species and seroprevalence determined; A. agrarius (45.6%), M. musculus (23.1%), M. fortis (48.4%), M. minutus (50.0%), T. triton (50.0%), and R. norvegicus (25.0%). A total of 31,184 chigger mites collected from 508 rodents and insectivores were slide-mounted and 10 species belonging to 4 genera were identified. Leptotrombidium pallidum (53.4%) was the most frequently collected, followed by L. palpale (15.7%), Neotrombicula tamiyai (14.3%), L. orientale (10.7%), L. zetum (3.1%), Walchia fragilis (2.1%), and L. gemiticulum (0.8%), while the remaining 3 species, L. subintermedium, N. gardellai, and Euschoengastia koreaensis were rarely observed (prevalence < 10%). In contrast to previous surveys, higher chigger indices of the primary scrub typhus vectors, L. pallidum (165.4), L. orientale (45.0), and L. palpale (21.4), were observed during the spring season.

  8. Fluvial geomorphology and aquatic-to-terrestrial Hg export are weakly coupled in small urban streams of Columbus, Ohio

    NASA Astrophysics Data System (ADS)

    Sullivan, S. Mažeika P.; Boaz, Lindsey E.; Hossler, Katie

    2016-04-01

    Although mercury (Hg) contamination is common in stream ecosystems, mechanisms governing bioavailability and bioaccumulation in fluvial systems remain poorly resolved as compared to lentic systems. In particular, streams in urbanized catchments are subject to fluvial geomorphic alterations that may contribute to Hg distribution, bioaccumulation, and export across the aquatic-to-terrestrial boundary. In 12 streams of urban Columbus, Ohio, we investigated the influence of fluvial geomorphic characteristics related to channel geometry, streamflow, and sediment size and distribution on (1) Hg concentrations in sediment and body burdens in benthic larval and adult emergent aquatic insects and (2) aquatic-to-terrestrial contaminant transfer to common riparian spiders of the families Pisauridae and Tetragnathidae via changes in aquatic insect Hg body burdens as well as in aquatic insect density and community composition. Hydrogeomorphic characteristics were weakly related to Hg body burdens in emergent insects (channel geometry) and tetragnathid spiders (streamflow), but not to Hg concentrations in sediment or benthic insects. Streamflow characteristics were also related to emergent insect density, while wider channels were associated with benthic insect community shifts toward smaller-bodied and more tolerant taxa (e.g., Chironomidae). Thus, our results provide initial evidence that fluvial geomorphology may influence aquatic-to-terrestrial contaminant Hg transfer through the collective effects on emergent insect body burdens as well as on aquatic insect community composition and abundance.

  9. A compact shielded exposure system for the simultaneous long-term UHF irradiation of forty small mammals: I. Electromagnetic and environmental design.

    PubMed

    Moros, E G; Straube, W L; Pickard, W F

    1998-01-01

    To carry out in vivo studies of the possible health effects of radiation from cellular telephone handsets, it is necessary to expose large numbers of small mammals at realistic power densities, modulations, and frequencies. Because even microwatt leakage could compromise the local cellular system, extreme care in shielding is required. Experimental logistics dictate, however, that the irradiated animals be easily accessed and that it be possible to irradiate them in small groups, while other groups are being loaded into or unloaded from the irradiators. This problem has been resolved by exposing the animals in aluminum-sheathed rectangular parallelepipeds, lined with microwave absorber and having doors that can be opened readily. Inside each of these microwave anechoic "chamberettes" is a vertical, four-element collinear array of dipole antennas; and around each antenna, 10 animal restrainers can be arranged like spokes on a wheel. The system has worked efficiently in studies of up to 480 rats. There is negligible coupling between antennas, and back reflection at an antenna's feed line is down 7-9 dB. Received CDMA power at the local base station is below the receiver's noise floor. Interior illumination reinforces the rats' diurnal rhythms, and the rats sleep during irradiation. Experimental logistics are excellent. In this paper, the irradiator design is presented.

  10. Marine Mammals.

    ERIC Educational Resources Information Center

    Meith, Nikki

    Marine mammals have not only fascinated and inspired human beings for thousands of years, but they also support a big business by providing flesh for sea-borne factories, sustaining Arctic lifestyles and traditions, and attracting tourists to ocean aquaria. While they are being harpooned, bludgeoned, shot, netted, and trained to jump through…

  11. Investigation of small-scale polygonal networks on Mars using models of terrestrial fracture and ice-wedge networks.

    NASA Astrophysics Data System (ADS)

    Plug, L. J.; Werner, B. T.

    2002-12-01

    Polygons formed by closely spaced (tens to hundreds of meters) interconnected troughs, visible in Mars Orbiter Camera images, are qualitatively similar to ice- and sand-wedge patterns in lowland Arctic and Antarctic terrain on Earth. The spacing and relative orientation between troughs in Mars networks varies between polygonal networks. Terrestrial networks, which form by recurrent opening of tension fractures in perennially frozen ground during periods of rapid cooling in winter, also display broad variations in the characteristic spacing, width and intersection angles of ice- and sand-wedges. Hypothesized causes for variations between terrestrial networks include variability in magnitude and orientation of maximum cooling-induced tensile stress, in substrate-dependent strength and heterogeneity, and in limits to downward propagation of fractures owing to a temperature-dependent brittle/ductile transition at depth. To investigate mechanisms for variability in Mars and terrestrial networks and to test if properties of some or all measured Mars networks fit within the range of terrestrial variability, we explore the response of a recently-developed computational model for terrestrial networks to changes in substrate strength and heterogeneity, maximum tensile stress, and fracture depth. The model treats initiation, propagation and arrest of fractures in a tensile stress field perturbed by neighboring fractures, and includes the growth of ice or sediment wedges along fracture paths. Modeled networks are compared to 20 1x1 km network regions from MOC images of Utopia Planitia using two methods. In the first method, joint distributions of relative orientation and spacing between troughs are used to characterize mean spacing and orthogonality of networks. In the second method, regions of a pixelated image of a network are used to predict the pixel pattern of displaced regions with a nonlinear spatial forecasting algorithm that operates on pixel brightness. Prediction

  12. Highly Diverse Morbillivirus-Related Paramyxoviruses in Wild Fauna of the Southwestern Indian Ocean Islands: Evidence of Exchange between Introduced and Endemic Small Mammals

    PubMed Central

    Mélade, Julien; Dietrich, Muriel; Ramasindrazana, Beza; Soarimalala, Voahangy; Lagadec, Erwan; le Minter, Gildas; Tortosa, Pablo; Heraud, Jean-Michel; de Lamballerie, Xavier; Goodman, Steven M.; Dellagi, Koussay

    2014-01-01

    ABSTRACT The Paramyxoviridae form an increasingly diverse viral family, infecting a wide variety of different hosts. In recent years, they have been linked to disease emergence in many different animal populations and in humans. Bats and rodents have been identified as major animal populations capable of harboring paramyxoviruses, and host shifting between these animals is likely to be an important driving factor in the underlying evolutionary processes that eventually lead to disease emergence. Here, we have studied paramyxovirus circulation within populations of endemic and introduced wild small mammals of the southwestern Indian Ocean region and belonging to four taxonomic orders: Rodentia, Afrosoricida, Soricomorpha, and Chiroptera. We report elevated infection levels as well as widespread paramyxovirus dispersal and frequent host exchange of a newly emerging genus of the Paramyxoviridae, currently referred to as the unclassified morbillivirus-related viruses (UMRVs). In contrast to other genera of the Paramyxoviridae, where bats have been shown to be a key host species, we show that rodents (and, in particular, Rattus rattus) are significant spreaders of UMRVs. We predict that the ecological particularities of the southwestern Indian Ocean, where small mammal species often live in densely packed, multispecies communities, in combination with the increasing invasion of R. rattus and perturbations of endemic animal communities by active anthropological development, will have a major influence on the dynamics of UMRV infection. IMPORTANCE Identification of the infectious agents that circulate within wild animal reservoirs is essential for several reasons: (i) infectious disease outbreaks often originate from wild fauna; (ii) anthropological expansion increases the risk of contact between human and animal populations and, as a result, the risk of disease emergence; (iii) evaluation of pathogen reservoirs helps in elaborating preventive measures to limit the risk

  13. The Effect of the Crayfish Orconectes virilis (Crustacea: Decapoda: Cambaridae) in the Decomposition and Succession of Submerged Small Mammal Carrion

    NASA Astrophysics Data System (ADS)

    de Jong, G. D.; Chadwick, J. W.

    2005-05-01

    The role of the crayfish Orconectes virilis in the decomposition of submerged rat carrion and succession of other benthic macroinvertebrates was experimentally investigated in Slaughterhouse Gulch, a small, urban stream in Littleton, Colorado. Crayfish participation in carrion decomposition significantly altered the decomposition rate of the carrion. Nine carcasses were exposed in anchored minnow traps at three degrees of crayfish access: crayfish always present, crayfish having free access, and crayfish excluded. These three treatments required 23 days, 29 days, and 65 days, respectively, for complete decomposition of the rat carrion (<2% original biomass). Sample variability increased with number of crayfish present, especially as decomposition proceeded. Seven other macroinvertebrate taxa were collected from the carcasses, but their presence or absence could not be correlated with crayfish presence. The leech Haemopis marmoratus was generally the first macroinvertebrate to arrive at the carrion, being present in densities of <5 individuals/carcass early in succession and in larger densities (up to 25 individuals/carcass) after extensive decomposition and exposure of the viscera.

  14. Audubon Mammal Study Program.

    ERIC Educational Resources Information Center

    National Audubon Society, New York, NY.

    Included are an illustrated student reader, "The Story of Mammals," a leaders' guide, a large wall chart picturing 39 North American mammals, and a separate booklet describing the mammals on the wall chart. The student reader presents these main topics: What Is a Mammal?; How Mammals Differ From Each Other; Where, When, and How To Find Mammals;…

  15. [Comparative morpho-functional characteristics of the organs of the reproductive system of small mammals under conditions of anthropogenic transformation of Southern Ural steppe ecosystems].

    PubMed

    Shevliuk, N N; Blinova, E V; Bokov, D A; Demina, L L; Elina, E E; Meshkova, O A; Ryskulov, M F

    2013-01-01

    The morpho-functional characteristics of reproductive organs of small mammals--striped field mouse (Apodemus agrarius Pallas, 1771), house mouse (Mus musculus Linnaeus, 1758), wood mouse (Sylvaemus uralensis Pallas, 1811), common vole (Microtus arvalis Pallas, 1778), bank vole (Clethrionomys glareolus Schreber, 1780), steppe lemming (Lagurus lagurus Pallas, 1773), little suslik (Spermophilus pygmaeus Pallas, 1778), and red-heeked suslik (Spermophilus major Pallas, 1779)--belonging to the populations inhabiting anthropogenically modified steppe landscapes (zones influenced by the ferrous metallurgy plants and gas processing plant, as well as the territory of the large city) were studied using histological, electron microscopic, immunocytochemical and morphometric methods. In animals studied, inhabiting technologically modified ecosystems, in contrast to those from ecologically safe regions, the testis demonstrated the increased destruction of spermatogenic epithelium. In the ovaries, the accelerated exhaustion of follicular reserve was detected. The increased embryonic death rate was also observed. The portion of the animals participating in reproduction was enlarged, the female fecundity was increased, while the age at puberty was decreased. Among the animal species studied, the variable degree of stability against the effect of the negative factors was demonstrated.

  16. Locomotion in some small to medium-sized mammals: a geometric morphometric analysis of the penultimate lumbar vertebra, pelvis and hindlimbs.

    PubMed

    Álvarez, Alicia; Ercoli, Marcos D; Prevosti, Francisco J

    2013-12-01

    We assessed the influence of a variety of aspects of locomotion and ecology including gait and locomotor types, maximal running speed, home range, and body size on postcranial shape variation in small to medium-sized mammals, employing geometric morphometric analysis and phylogenetic comparative methods. The four views analyzed, i.e., dorsal view of the penultimate lumbar vertebra, lateral view of the pelvis, posterior view of the proximal femur and proximal view of the tibia, showed clear phylogenetic signal and interesting patterns of association with movement. Variation in home range size was related to some tibia shape changes, while speed was associated with lumbar vertebra, pelvis and tibia shape changes. Femur shape was not related to any locomotor variables. In both locomotor type and high-speed gait analyses, locomotor groups were distinguished in both pelvis and tibia shape analyses. These results suggest that adaptations to both typical and high-speed gaits could explain a considerable portion of the shape of those elements. In addition, lumbar vertebra and tibia showed non-significant relationships with body mass, which suggests that they might be used in morpho-functional analyses and locomotor inferences on fossil taxa, with little or no bias for body size. Lastly, we observed morpho-functional convergences among several mammalian taxa and detected some taxa that achieve similar locomotor features following different morphological paths.

  17. Small mammal diversity and habitat requirements in the Kahuzi-Biega National Park and surrounding areas, eastern Democratic Republic of Congo.

    PubMed

    Kaleme, Prince K; Bates, John; Peterans, Julian Kerbis; Jacques, Mwanga M; Ndara, Benjamin R

    2007-12-01

    We conducted a study on diversity and habitat requirements of small mammals in the western part of the Albertine Rift, eastern Democratic Republic of Congo. The work aimed at providing a more complete list of species recorded to date and their habitat requirements to aid conservation efforts in the region. Trapping was conducted using Museum special, Victor traps, Sherman live traps and pitfall traps in four different habitats. A total of 57 species was recorded. Plantations and open habitats harbored the same species. In the forested areas we recorded 30 species which are not tolerant to disturbance. Eighteen species are Albertine Rift endemics. One species (Lophuromys cinereus), which is vulnerable and data deficient, has been recorded only in swamp. This study has recorded more species than the previous studies, some of which have not been reported in earlier studies. Differences between this and earlier studies are attributed to methods and the areas sampled. Some of the habitats sampled by previous workers have not been assessed. More research is needed, especially in swamps in mountain areas and in deep forests inhabited by species not present at lower altitudes.

  18. Some laelapine mites (Acari: Laelapidae) ectoparasitic on small mammals in the Galapagos Islands, including a new species of Gigantolaelaps from Aegialomys galapagoensis.

    PubMed

    Gettinger, Donald; Martins-Hatano, Fernanda; Gardner, Scott L

    2011-08-01

    A collection of laelapine mites from small mammals in the Galapagos Islands are identified and their host distributions reviewed. Two species of native rodents, Aegialomys galapagoensis and Nesoryzomys narboroughii, were infested only with laelapine species typical of Neotropical oryzomyine rodents; Rattus rattus was infested with Laelaps nuttalli, a host-specific ectoparasite endemic to Old World Rattus. A synopsis of Gigantolaelaps Fonseca is provided and we describe a new laelapine mite, Gigantolaelaps aegialomys n. sp., from the pelage of the rodent A. galapagoensis on Santa Fe Island. The new species has strong morphological affinities with a subgroup of Gigantolaelaps associated with a group of semiaquatic oryzomyine rodents ( Holochilus, Nectomys, Sooretamys, Pseudoryzomys , Oryzomys palustris). The other nominal species of this group, Gigantolaelaps mattogrossensis (Fonseca, 1935) and Gigantolaelaps goyanensis Fonseca, 1939 , are characterized by 10 setae on Tibia IV, large metapodal shields, and spiniform setae on Coxae I. Gigantolaelaps aegialomys is distinguished from these species by a lack of clearly spiniform setae on Coxa I, with setiform distal seta longer than the proximal; metapodal shields about the same size as the stigma; less than 100 µm separating the first pair of sternal setae.

  19. Borrelia burgdorferi sensu lato prevalence and diversity in ticks and small mammals in a Lyme borreliosis endemic Nature Reserve in North-Western Spain. Incidence in surrounding human populations.

    PubMed

    Espí, Alberto; Del Cerro, Ana; Somoano, Aitor; García, Verónica; M Prieto, José; Barandika, José F; García-Pérez, Ana L

    2016-07-18

    To determine the prevalence and diversity of Borrelia burgdorferi sensu lato (s.l.) in an endemic Nature Reserve (Sierra del Sueve) in North-Western Spain, and the risk of human exposure to infected ticks in Asturias, 1013 questing ticks and 70 small mammals were collected between 2012 and 2014. A retrospective descriptive analysis was also carried out on human Lyme borreliosis (LB) cases reported to the local hospital (Cabueñes). Samples were screened for B. burgdorferi s.l. presence by a nested PCR assay, and genospecies were confirmed by sequencing. B. burgdorferi s.l. was detected in 1.4% (12/845) of I. ricinus questing nymphs, 9.1% (2/33) of questing adults, and 12.9% (9/70) of small mammals, as well as in the other tick species. PCR positive samples of 17 questing tick and 6 small mammals were sequenced. Four genospecies were identified: B. afzelii, B. garinii, B. lusitaniae, and B. valaisiana. Phylogenetic analyses based on the flaB gene showed the heterogeneity of B. afzelii in this area. The detection of B. burgdorferi s.l. among questing ticks and small mammals in the study area, as well as the abundance of ticks and of large wild and domestic mammals, indicate a high risk of infection by B. burgdorferi s.l. in the area. Reporting of LB cases to the local hospital support this, and shows the need of thorough monitoring of B. burgdorferi infection in ticks and hosts in the area. More investigations are needed to assess the role of different wildlife species and the risk of transmission to humans.

  20. Application of terrestrial laser scanning for detection of ground surface deformation in small mud volcano (Murono, Japan)

    NASA Astrophysics Data System (ADS)

    Hayakawa, Yuichi S.; Kusumoto, Shigekazu; Matta, Nobuhisa

    2016-07-01

    We perform terrestrial laser scanning (TLS) to detect changes in surface morphology of a mud volcano in Murono, north-central Japan. The study site underwent significant deformation by a strong earthquake in 2011, and the surface deformation has continued in the following years. The point cloud datasets were obtained by TLS at three different times in 2011, 2013 and 2014. Those point clouds were aligned by cloud-based registration, which minimizes the closest point distance of point clouds of unchanged ground features, and the TLS-based point cloud data appear to be suitable for detecting centimeter-order deformations in the central domain of the mud volcano, as well as for measurements of topographic features including cracks of paved ground surface. The spatial patterns and accumulative amount of the vertical deformation during 2011-2014 captured by TLS correspond well with those previously reported based on point-based leveling surveys, supporting the validity of TLS survey.

  1. [Control of harmful mammals].

    PubMed

    van Eerdenburg, F J; Bouw, J; Zwart, P

    1987-07-15

    In the Netherlands, several millions of injurious small mammals are killed yearly. This concerns not only mice and rats but also moles, musk-rats and several other species of rodent. At the request of the Netherlands Society for the Protection of Animals, studies were done on the methods in killing these animals, the effectiveness of these methods and the possibilities of reducing the harm done to the animals. The most important results of these investigations are reported in the present paper.

  2. Ectoparasites of African Mammals.

    DTIC Science & Technology

    1976-11-30

    This study consisted of ectoparasites from approximately 100,000 African small mammals, representing probably more than 500 species of which many are...study of ectoparasites may provide information concerning interactions among animal reservoirs of disease, and (3) an understanding of ecological...parameters for ectoparasites and their hosts may enhance understanding of epidemiological patterns. Of the four major groups dealt with, considerably more

  3. Alaska Wilderness: A Bibliography for Secondary Students on Marine Vertebrates, Birds, Small or Fur Bearing Mammals and Game Animals of Alaska.

    ERIC Educational Resources Information Center

    Symons, Ann

    This is an annotated bibliography for secondary school students. It contains fourteen entries on marine vertebrates, nine entries on birds, twenty-nine entries on mammals, and one on amphibians and reptiles. Some of the entries are fiction. (BB)

  4. Upstream Freshwater and Terrestrial Sources Are Differentially Reflected in the Bacterial Community Structure along a Small Arctic River and Its Estuary

    PubMed Central

    Hauptmann, Aviaja L.; Markussen, Thor N.; Stibal, Marek; Olsen, Nikoline S.; Elberling, Bo; Bælum, Jacob; Sicheritz-Pontén, Thomas; Jacobsen, Carsten S.

    2016-01-01

    Glacier melting and altered precipitation patterns influence Arctic freshwater and coastal ecosystems. Arctic rivers are central to Arctic water ecosystems by linking glacier meltwaters and precipitation with the ocean through transport of particulate matter and microorganisms. However, the impact of different water sources on the microbial communities in Arctic rivers and estuaries remains unknown. In this study we used 16S rRNA gene amplicon sequencing to assess a small river and its estuary on the Disko Island, West Greenland (69°N). Samples were taken in August when there is maximum precipitation and temperatures are high in the Disko Bay area. We describe the bacterial community through a river into the estuary, including communities originating in a glacier and a proglacial lake. Our results show that water from the glacier and lake transports distinct communities into the river in terms of diversity and community composition. Bacteria of terrestrial origin were among the dominating OTUs in the main river, while the glacier and lake supplied the river with water containing fewer terrestrial organisms. Also, more psychrophilic taxa were found in the community supplied by the lake. At the river mouth, the presence of dominant bacterial taxa from the lake and glacier was unnoticeable, but these taxa increased their abundances again further into the estuary. On average 23% of the estuary community consisted of indicator OTUs from different sites along the river. Environmental variables showed only weak correlations with community composition, suggesting that hydrology largely influences the observed patterns. PMID:27708629

  5. Small global effect on terrestrial net primary production due to increased fossil fuel aerosol emissions from East Asia during the last decade.

    NASA Astrophysics Data System (ADS)

    O'Sullivan, Michael; Rap, Alex; Reddington, Carly; Spracklen, Dominick; Buermann, Wolfgang

    2016-04-01

    The global terrestrial carbon sink has increased since the start of this century at a time of rapidly growing carbon dioxide emissions from fossil fuel burning. Here we test the hypothesis that increases in atmospheric aerosols from fossil fuel burning have increased the diffuse fraction of incoming solar radiation and the efficiency of photosynthesis leading to increased plant carbon uptake. Using a combination of atmospheric and biospheric models, we find that changes in diffuse light associated with fossil fuel aerosol emission accounts for only 2.8% of the increase in global net primary production (1.221 PgC/yr) over the study period 1998 to 2007. This relatively small global signal is however a result of large regional compensations. Over East Asia, the strong increase in fossil fuel emissions contributed nearly 70% of the increased plant carbon uptake (21 TgC/yr), whereas the declining fossil fuel aerosol emissions in Europe and North America contributed negatively (-16% and -54%, respectively) to increased plant carbon uptake. At global scale, we also find the CO2 fertilization effect on photosynthesis to be the dominant driver of increased plant carbon uptake, in line with previous studies. These results suggest that further research into alternative mechanisms by which fossil fuel emissions could increase carbon uptake, such as nitrogen deposition and carbon-nitrogen interactions, is required to better understand a potential link between the recent changes in fossil fuel emissions and terrestrial carbon uptake.

  6. Baseline Radionuclide and Nonradionuclide Concentrations in Soils, Vegetation, and Small Mammals at the Proposed Expansion Area at TA-54 Area G

    SciTech Connect

    D. D. Romero, P. R. Fresquez

    2007-11-30

    Area G is a 25.5-hectare (63-acre), fenced, low-level radioactive solid waste processing and disposal area located on the east end of Mesa del Buey at Technical Area 54 at Los Alamos National Laboratory. This disposal area has been in existence since 1957 and is expected to be filled by the yea