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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. Wildlife of southern forests habitat & management (Chapter 26): Terrestrial Small Mammals

    Treesearch

    James G. Dickson

    2003-01-01

    A variety of terrestrial small mammals with diverse size, form, geo- graphic range, and ecological niche inhabit southern forests. Some are highly specialized for their environment, such as the semi-aquatic species or fossorial species, such as moles. Some, such as the cotton rat, are widely distributed throughout the region and others highly restrictive in their range...

  3. 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.

  4. 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.

  5. Response of terrestrial small mammals to varying amounts and patterns of green-tree retention in Pacific Northwest forests

    Treesearch

    Robert A. Gitzen; Stephen West; Chris C. Maguireb; Tom Manning; Charles B. Halpern

    2007-01-01

    To sustain native species in managed forests, landowners need silvicultural strategies that retain habitat elements often eliminated during traditional harvests such as clearcut logging. One alternative is green-tree or variable retention. We investigated the response of terrestrial small mammals to experimental harvests that retained large live trees in varying...

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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

  11. 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

  12. Small Mammal Intrigue.

    ERIC Educational Resources Information Center

    Cristol, Daniel A.

    1985-01-01

    Gives introductory information about the study of small mammals including the selection and use of harmless live-traps, handling and identification, techniques for observation and trapping in the wild, and safety measures. Suggests useful references for teachers wishing to develop a small mammal study program for their students. (JHZ)

  13. Terrestrial and aquatic mammals of the Pantanal.

    PubMed

    Alho, C J R; Camargo, G; Fischer, E

    2011-04-01

    Different works have registered the number of mammal species within the natural habitats of the Pantanal based on currently known records, with species richness ranging from 89 to 152 of annotated occurrences. Our present list sums 174 species. However, at least three factors have to be emphasised to deal with recorded numbers: 1) to establish the ecotone limit between the floodplain (which is the Pantanal) and its neighbouring domain like the Cerrado, besides the existence of maps recently produced; 2) the lack of intensive surveys, especially on small mammals, rodents and marsupials; and 3) the constant taxonomic revision on bats, rodents and marsupials. Some species are very abundant--for example the capybara Hydrochoerus hydrochaeris and the crab-eating fox Cerdocyon thous, and some are rare, and others are still intrinsically rare--for example, the bush dog Speothos venaticus. Abundance of species is assumed to reflect ecological resources of the habitat. Local diversity and number of individuals of wild rodents and marsupials also rely on the offering of ecological resources and behavioural specialisation to microhabitat components. A large number of species interact with the type of the vegetation of the habitat, by means of habitat selection through active patterns of ecological behaviour, resulting on dependency on arboreal and forested habitats of the Pantanal. In addition, mammals respond to seasonal shrinking-and-expansion of habitats due to flooding regime of the Pantanal. The highest number of species is observed during the dry season, when there is a considerable expansion of terrestrial habitats, mainly seasonally flooded grassland. Major threats to mammal species are the loss and alteration of habitats due to human intervention, mainly deforestation, unsustainable agricultural and cattle-ranching practices, which convert the natural vegetation into pastures. The Pantanal still harbours about a dozen of species officially listened as in danger.

  14. Identification of Ebola virus sequences present as RNA or DNA in organs of terrestrial small mammals of the Central African Republic.

    PubMed

    Morvan, J M; Deubel, V; Gounon, P; Nakouné, E; Barrière, P; Murri, S; Perpète, O; Selekon, B; Coudrier, D; Gautier-Hion, A; Colyn, M; Volehkov, V

    1999-12-01

    The life cycle of the Ebola (EBO) virus remains enigmatic. We tested for EBO virus in the organs of 242 small mammals captured during ecological studies in the Central African Republic. EBO virus glycoprotein or polymerase gene sequences were detected by reverse transcription PCR in RNA extracts of the organs of seven animals and by PCR in DNA extract of one animal. Neither live virus nor virus antigen was detected in any organ sample. Direct sequencing of amplicons identified the virus as being of the Zaire/Gabon subtype. Virus-like nucleocapsids were observed by electron microscopy in the cytoplasm of the spleen cells of one animal. The animals belonged to two genera of rodents (Muridae; Mus setulosus, Praomys sp1 and P. sp2) and one species of shrew (Soricidae; Sylvisorex ollula). These preliminary results provide evidence that common terrestrial small mammals living in peripheral forest areas have been in contact with the EBO virus and demonstrate the persistence of EBO virus RNA and DNA in the organs of the animals. Our findings should lead to better targeting of research into the life cycle of the EBO virus.

  15. Global habitat suitability models of terrestrial mammals.

    PubMed

    Rondinini, Carlo; Di Marco, Moreno; Chiozza, Federica; Santulli, Giulia; Baisero, Daniele; Visconti, Piero; Hoffmann, Michael; Schipper, Jan; Stuart, Simon N; Tognelli, Marcelo F; Amori, Giovanni; Falcucci, Alessandra; Maiorano, Luigi; Boitani, Luigi

    2011-09-27

    Detailed large-scale information on mammal distribution has often been lacking, hindering conservation efforts. We used the information from the 2009 IUCN Red List of Threatened Species as a baseline for developing habitat suitability models for 5027 out of 5330 known terrestrial mammal species, based on their habitat relationships. We focused on the following environmental variables: land cover, elevation and hydrological features. Models were developed at 300 m resolution and limited to within species' known geographical ranges. A subset of the models was validated using points of known species occurrence. We conducted a global, fine-scale analysis of patterns of species richness. The richness of mammal species estimated by the overlap of their suitable habitat is on average one-third less than that estimated by the overlap of their geographical ranges. The highest absolute difference is found in tropical and subtropical regions in South America, Africa and Southeast Asia that are not covered by dense forest. The proportion of suitable habitat within mammal geographical ranges correlates with the IUCN Red List category to which they have been assigned, decreasing monotonically from Least Concern to Endangered. These results demonstrate the importance of fine-resolution distribution data for the development of global conservation strategies for mammals.

  16. Global habitat suitability models of terrestrial mammals

    PubMed Central

    Rondinini, Carlo; Di Marco, Moreno; Chiozza, Federica; Santulli, Giulia; Baisero, Daniele; Visconti, Piero; Hoffmann, Michael; Schipper, Jan; Stuart, Simon N.; Tognelli, Marcelo F.; Amori, Giovanni; Falcucci, Alessandra; Maiorano, Luigi; Boitani, Luigi

    2011-01-01

    Detailed large-scale information on mammal distribution has often been lacking, hindering conservation efforts. We used the information from the 2009 IUCN Red List of Threatened Species as a baseline for developing habitat suitability models for 5027 out of 5330 known terrestrial mammal species, based on their habitat relationships. We focused on the following environmental variables: land cover, elevation and hydrological features. Models were developed at 300 m resolution and limited to within species' known geographical ranges. A subset of the models was validated using points of known species occurrence. We conducted a global, fine-scale analysis of patterns of species richness. The richness of mammal species estimated by the overlap of their suitable habitat is on average one-third less than that estimated by the overlap of their geographical ranges. The highest absolute difference is found in tropical and subtropical regions in South America, Africa and Southeast Asia that are not covered by dense forest. The proportion of suitable habitat within mammal geographical ranges correlates with the IUCN Red List category to which they have been assigned, decreasing monotonically from Least Concern to Endangered. These results demonstrate the importance of fine-resolution distribution data for the development of global conservation strategies for mammals. PMID:21844042

  17. Future hotspots of terrestrial mammal loss.

    PubMed

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

    2011-09-27

    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.

  18. 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

  19. 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.

  20. Small Mammals, Reptiles, and Amphibians

    Treesearch

    Bryce Rickel

    2005-01-01

    This chapter focuses on small mammals, reptiles, and amphibians that inhabit the grasslands within the Southwestern Region of the USDA Forest Service. The chapter is not intended to be an all inclusive list of species, but rather to address the species that play important roles in grassland ecosystems and that often are associated with the management of grasslands....

  1. 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...

  2. 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

  3. 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.

  4. River conservation and terrestrial mammals: key ecological processes

    Treesearch

    Thomas A. Hanley

    2008-01-01

    Key ecological processes affecting interactions between rivers and terrestrial mammals are identified and explained, using flood plains of Alaska as examples of relatively pristine systems. Both coastal (southeast Alaska) and interior Alaska examples are used. Coastal Alaskan rivers tend to be relatively short, flashy, rain-driven systems, whereas interior Alaska...

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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)

  11. Quantification of habitat fragmentation reveals extinction risk in terrestrial mammals.

    PubMed

    Crooks, Kevin R; Burdett, Christopher L; Theobald, David M; King, Sarah R B; Di Marco, Moreno; Rondinini, Carlo; Boitani, Luigi

    2017-07-18

    Although habitat fragmentation is often assumed to be a primary driver of extinction, global patterns of fragmentation and its relationship to extinction risk have not been consistently quantified for any major animal taxon. We developed high-resolution habitat fragmentation models and used phylogenetic comparative methods to quantify the effects of habitat fragmentation on the world's terrestrial mammals, including 4,018 species across 26 taxonomic Orders. Results demonstrate that species with more fragmentation are at greater risk of extinction, even after accounting for the effects of key macroecological predictors, such as body size and geographic range size. Species with higher fragmentation had smaller ranges and a lower proportion of high-suitability habitat within their range, and most high-suitability habitat occurred outside of protected areas, further elevating extinction risk. Our models provide a quantitative evaluation of extinction risk assessments for species, allow for identification of emerging threats in species not classified as threatened, and provide maps of global hotspots of fragmentation for the world's terrestrial mammals. Quantification of habitat fragmentation will help guide threat assessment and strategic priorities for global mammal conservation.

  12. 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

  13. 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.

  14. Myoglobin oxygen affinity in aquatic and terrestrial birds and mammals.

    PubMed

    Wright, Traver J; Davis, Randall W

    2015-07-01

    Myoglobin (Mb) is an oxygen binding protein found in vertebrate skeletal muscle, where it facilitates intracellular transport and storage of oxygen. This protein has evolved to suit unique physiological needs in the muscle of diving vertebrates that express Mb at much greater concentrations than their terrestrial counterparts. In this study, we characterized Mb oxygen affinity (P50) from 25 species of aquatic and terrestrial birds and mammals. Among diving species, we tested for correlations between Mb P50 and routine dive duration. Across all species examined, Mb P50 ranged from 2.40 to 4.85 mmHg. The mean P50 of Mb from terrestrial ungulates was 3.72±0.15 mmHg (range 3.70-3.74 mmHg). The P50 of cetaceans was similar to terrestrial ungulates ranging from 3.54 to 3.82 mmHg, with the exception of the melon-headed whale, which had a significantly higher P50 of 4.85 mmHg. Among pinnipeds, the P50 ranged from 3.23 to 3.81 mmHg and showed a trend for higher oxygen affinity in species with longer dive durations. Among diving birds, the P50 ranged from 2.40 to 3.36 mmHg and also showed a trend of higher affinities in species with longer dive durations. In pinnipeds and birds, low Mb P50 was associated with species whose muscles are metabolically active under hypoxic conditions associated with aerobic dives. Given the broad range of potential globin oxygen affinities, Mb P50 from diverse vertebrate species appears constrained within a relatively narrow range. High Mb oxygen affinity within this range may be adaptive for some vertebrates that make prolonged dives. © 2015. Published by The Company of Biologists Ltd.

  15. 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.

  16. 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.

  17. 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.

  18. A system for gathering small mammal data

    Treesearch

    Robert D. Neely; Robert W. Campbell

    1973-01-01

    As an aid to studying vertebrate predators of the gypsy moth, a radio telemetry system was designed to detect the death of small mammals and facilitate recovery of the remains. An intraperitoneally implanted radio transmitter is triggered by the drop in body temperature when the animal dies. The device was tested in white-footed mice.

  19. 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.

  20. The Celtic fringe of Britain: insights from small mammal phylogeography.

    PubMed

    Searle, Jeremy B; Kotlík, Petr; Rambau, Ramugondo V; Marková, Silvia; Herman, Jeremy S; McDevitt, Allan D

    2009-12-22

    Recent genetic studies have challenged the traditional view that the ancestors of British Celtic people spread from central Europe during the Iron Age and have suggested a much earlier origin for them as part of the human recolonization of Britain at the end of the last glaciation. Here we propose that small mammals provide an analogue to help resolve this controversy. Previous studies have shown that common shrews (Sorex araneus) with particular chromosomal characteristics and water voles (Arvicola terrestris) of a specific mitochondrial (mt) DNA lineage have peripheral western/northern distributions with striking similarities to that of Celtic people. We show that mtDNA lineages of three other small mammal species (bank vole Myodes glareolus, field vole Microtus agrestis and pygmy shrew Sorex minutus) also form a 'Celtic fringe'. We argue that these small mammals most reasonably colonized Britain in a two-phase process following the last glacial maximum (LGM), with climatically driven partial replacement of the first colonists by the second colonists, leaving a peripheral geographical distribution for the first colonists. We suggest that these natural Celtic fringes provide insight into the same phenomenon in humans and support its origin in processes following the end of the LGM.

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. Small mammal communities of high elevation central Appalachian wetlands

    Treesearch

    Karen E. Francl; Steven B. Castleberry; W. Mark Ford

    2004-01-01

    We surveyed small mammal assemblages at 20 high-elevation wetlands in West Virginia and Maryland and examined relationships among mammal capture rates, richness and evenness and landscape features at multiple spatial scales. In 24,693 trap nights we captured 1451 individuals of 12 species. Small mammal species richness increased with wetland size and was negatively...

  6. 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.

  7. 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.

  8. 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.

  9. Thinning effects on spotted owl prey and other forest-dwelling small mammals

    Treesearch

    Todd M. Willson; Eric D. Forsman

    2013-01-01

    Th inning has been promoted as a method for accelerating the development of late-seral habitat and improving the overall health and function of young forests in the Pacifi c Northwest. Population studies have shown early and positive responses to thinning by some small forest-floor mammals (primarily mice, terrestrial voles, and shrews). However, thinning reduces the...

  10. 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.

  11. 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

  12. 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.

  13. Small mammals as monitors of environmental contaminants

    SciTech Connect

    Talmage, S.S.; Walton, B.T. )

    1991-01-01

    The merit of using small mammals as monitors of environmental contaminants was assessed using data from the published literature. Information was located on 35 species of small mammals from 7 families used to monitor heavy metals, radionuclides, and organic chemicals at mine sites, industrial areas, hazardous and radioactive waste disposal sites, and agricultural and forested land. To document foodchain transfer of chemicals, concentrations in soil, vegetation, and invertebrates, where available, were included. The most commonly trapped North American species were Peromyscus leucopus, Blarina brevicauda, and Microtus pennsylvanicus. In these species, exposure to chemicals was determined from tissue residue analyses, biochemical assays, and cytogenetic assays. Where enough information was available, suitable target tissues, or biological assays for specific chemicals were noted. In general, there was a relationship between concentrations of contaminants in the soil or food, and concentrations in target tissues of several species. This relationship was most obvious for the nonessential heavy metals, cadmium, lead, and mercury and for fluoride. Kidney was the single best tissue for residue analyses of inorganic contaminants. However, bone should be the tissue of choice for both lead and fluorine. Exposure to lead was also successfully documented using biochemical and histopathological endpoints. Bone was the tissue of choice for exposure to 90Sr, whereas muscle was an appropriate tissue for 137Cs. For organic contaminants, exposure endpoints depended on the chemical(s) of concern. Liver and whole-body residue analyses, as well as enzyme changes, organ histology, genotoxicity, and, in one case, population dynamics, were successfully used to document exposure to these contaminants.

  14. 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.

  15. 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.

  16. Small mammal populations after a wildfire in northeast Minnesota.

    Treesearch

    Richard R. Buech; Karl Siderits; Robert E. Radtke; Howard L. Sheldon; Donald Elsing

    1977-01-01

    Small mammals were studied shortly after a large wildfire in northeast Minnesota. An average of only 16 as many small mammals were in three forest communities that had burned than were in comparable unburned areas. The greatest reduction was for the red-backed vole. An analysis of population attributes suggests that deer mice immigrated to the burned area. Small...

  17. 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

  18. 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.

  19. 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. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. 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.

  1. A Comparison of Snap Traps for Evaluating Small Mammal Populations

    Treesearch

    Roger W. Perry; Philip A. Tappe; David G. Peitz; Ronald E. Thill; M. Anthony Melchoirs; T. Bently Wigley

    1996-01-01

    The authors compared rat, mouse, and museum special snap traps to determine if differences existed in capture efficiency of small mammals and whether type of trap affected indices of richness, evenness, and diversity. Small mammals were trapped in 57 streamside study areas in 1990 to 1995 in the Ouachita Mountains, AR. Efficiency of mouse traps was equal to or greater...

  2. Small mammal populations in a restored stream corridor

    Treesearch

    Lynn D. Wike; F. Douglas Martin; Hugh G. Hanlin; Linda S. Paddock

    2000-01-01

    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 Meyers branch, an unimpacted stream at SRS, in 1997 and 1998. Distributions...

  3. 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

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

    PubMed

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

    2015-06-01

    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. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. 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).

  6. Forelimb bone curvature in terrestrial and arboreal mammals

    PubMed Central

    Henderson, Keith; Pantinople, Jess; McCabe, Kyle; Milne, Nick

    2017-01-01

    It has recently been proposed that the caudal curvature (concave caudal side) observed in the radioulna of terrestrial quadrupeds is an adaptation to the habitual action of the triceps muscle which causes cranial bending strains (compression on cranial side). The caudal curvature is proposed to be adaptive because longitudinal loading induces caudal bending strains (increased compression on the caudal side), and these opposing bending strains counteract each other leaving the radioulna less strained. If this is true for terrestrial quadrupeds, where triceps is required for habitual elbow extension, then we might expect that in arboreal species, where brachialis is habitually required to maintain elbow flexion, the radioulna should instead be cranially curved. This study measures sagittal curvature of the ulna in a range of terrestrial and arboreal primates and marsupials, and finds that their ulnae are curved in opposite directions in these two locomotor categories. This study also examines sagittal curvature in the humerus in the same species, and finds differences that can be attributed to similar adaptations: the bone is curved to counter the habitual muscle action required by the animal’s lifestyle, the difference being mainly in the distal part of the humerus, where arboreal animals tend have a cranial concavity, thought to be in response the carpal and digital muscles that pull cranially on the distal humerus. PMID:28462036

  7. Forelimb bone curvature in terrestrial and arboreal mammals.

    PubMed

    Henderson, Keith; Pantinople, Jess; McCabe, Kyle; Richards, Hazel L; Milne, Nick

    2017-01-01

    It has recently been proposed that the caudal curvature (concave caudal side) observed in the radioulna of terrestrial quadrupeds is an adaptation to the habitual action of the triceps muscle which causes cranial bending strains (compression on cranial side). The caudal curvature is proposed to be adaptive because longitudinal loading induces caudal bending strains (increased compression on the caudal side), and these opposing bending strains counteract each other leaving the radioulna less strained. If this is true for terrestrial quadrupeds, where triceps is required for habitual elbow extension, then we might expect that in arboreal species, where brachialis is habitually required to maintain elbow flexion, the radioulna should instead be cranially curved. This study measures sagittal curvature of the ulna in a range of terrestrial and arboreal primates and marsupials, and finds that their ulnae are curved in opposite directions in these two locomotor categories. This study also examines sagittal curvature in the humerus in the same species, and finds differences that can be attributed to similar adaptations: the bone is curved to counter the habitual muscle action required by the animal's lifestyle, the difference being mainly in the distal part of the humerus, where arboreal animals tend have a cranial concavity, thought to be in response the carpal and digital muscles that pull cranially on the distal humerus.

  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. 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

  11. Examining predator–prey body size, trophic level and body mass across marine and terrestrial mammals

    PubMed Central

    Tucker, Marlee A.; Rogers, Tracey L.

    2014-01-01

    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. PMID:25377460

  12. 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.

  13. Small mammals in young forests: implications for management for sustainability.

    Treesearch

    A.B. Carey; C.A. Harrington

    2001-01-01

    Small mammals have been proposed as indicators of sustainability in forests in the Pacific Northwest and elsewhere. Mammal community composition and species abundances purportedly result from interactions among species, forest-floor characteristics, large coarse woody debris, understory vegetation, and overstory composition. Coarse woody debris is thought to be...

  14. 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

  15. 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.

  16. 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.

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

    PubMed Central

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

    2012-01-01

    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. PMID:23185018

  18. 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

  19. Small mammals in oak woodlands in the Puget Trough, Washington.

    Treesearch

    S.M. Wilson; A.B. Carey

    2001-01-01

    We surveyed the 22 largest sites dominated by Oregon white oaks on the Fort Lewis Military Reservation, Washington, to determine small-mammal community structure and population abundances. Study areas were in the Puget Trough physiographic province and western hemlock vegetation zone. Most oak communities were ecotonal between prairie and Douglas-fir forest. Small...

  20. 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

  1. Small mammals of the Bitterroot National Forest: A literature review and annotated bibliography

    Treesearch

    Dean E. Pearson

    1999-01-01

    Small mammal literature from western Montana and the Northern Rocky Mountains was reviewed to assess the ecological role of small mammals on the Bitterroot National Forest of western Montana and in the Northern Rocky Mountains. The goal was to understand how small mammals relate to succession and how proposed ecosystem management goals would affect small mammals, the...

  2. Exotic Small Mammals as Potential Reservoirs of Zoonotic Bartonella spp.

    PubMed Central

    Inoue, Kai; Kabeya, Hidenori; Hagiya, Keiko; Izumi, Yasuhito; Une, Yumi; Yoshikawa, Yasuhiro

    2009-01-01

    To evaluate the risk for emerging human infections caused by zoonotic Bartonella spp. from exotic small mammals, we investigated the prevalence of Bartonella spp. in 546 small mammals (28 species) that had been imported into Japan as pets from Asia, North America, Europe, and the Middle and Near East. We obtained 407 Bartonella isolates and characterized them by molecular phylogenetic analysis of the citrate synthase gene, gltA. The animals examined carried 4 zoonotic Bartonella spp. that cause human endocarditis and neuroretinitis and 6 novel Bartonella spp. at a high prevalence (26.0%, 142/546). We conclude that exotic small mammals potentially serve as reservoirs of several zoonotic Bartonella spp. PMID:19331727

  3. 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.

  4. 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.

  5. Tick infestation of small mammals in an English woodland.

    PubMed

    Cull, Benjamin; Vaux, Alexander G C; Ottowell, Lisa J; Gillingham, Emma L; Medlock, Jolyon M

    2017-06-01

    Tick infestations on small mammals were studied from April to November, 2010, in deciduous woodland in southern England in order to determine whether co-infestations with tick stages occurred on small mammals, a key requirement for endemic transmission of tick-borne encephalitis virus (TBEV). A total of 217 small mammals was trapped over 1,760 trap nights. Yellow-necked mice (Apodemus flavicollis) made up the majority (52.5%) of animals, followed by wood mice (A. sylvaticus) 35.5% and bank voles (Myodes glareolus) 12%. A total of 970 ticks was collected from 169 infested animals; 96% of ticks were Ixodes ricinus and 3% I. trianguliceps. Over 98% of ticks were larval stages. Mean infestation intensities of I. ricinus were significantly higher on A. flavicollis (6.53 ± 0.67) than on A. sylvaticus (4.96 ± 0.92) and M. glareolus (3.25 ± 0.53). Infestations with I. ricinus were significantly higher in August than in any other month. Co-infestations with I. ricinus nymphs and larvae were observed on six (3.6%) infested individuals, and fifteen small mammals (8.9%) supported I. ricinus - I. trianguliceps co-infestations. This work contributes further to our understanding of European small mammal hosts that maintain tick populations and their associated pathogens, and indicates that co-infestation of larvae and nymph ticks does occur in lowland UK. The possible implications for transmission of tick-borne encephalitis virus between UK ticks and small mammals are discussed. © 2017 The Society for Vector Ecology.

  6. 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.

  7. 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).

  8. 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.

  9. Dental functional traits of mammals resolve productivity in terrestrial ecosystems past and present

    PubMed Central

    Liu, Liping; Puolamäki, Kai; Eronen, Jussi T.; Ataabadi, Majid M.; Hernesniemi, Elina; Fortelius, Mikael

    2012-01-01

    We have recently shown that rainfall, one of the main climatic determinants of terrestrial net primary productivity (NPP), can be robustly estimated from mean molar tooth crown height (hypsodonty) of mammalian herbivores. Here, we show that another functional trait of herbivore molar surfaces, longitudinal loph count, can be similarly used to extract reasonable estimates of rainfall but also of temperature, the other main climatic determinant of terrestrial NPP. Together, molar height and the number of longitudinal lophs explain 73 per cent of the global variation in terrestrial NPP today and resolve the main terrestrial biomes in bivariate space. We explain the functional interpretation of the relationships between dental function and climate variables in terms of long- and short-term demands. We also show how the spatially and temporally dense fossil record of terrestrial mammals can be used to investigate the relationship between biodiversity and productivity under changing climates in geological time. The placement of the fossil chronofaunas in biome space suggests that they most probably represent multiple palaeobiomes, at least some of which do not correspond directly to any biomes of today's world. PMID:22456884

  10. 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.

  11. Legacy retention versus thinning: influences on small mammals.

    Treesearch

    S.M. Wilson; A.B. Carey

    2000-01-01

    Management strategies for promoting late-seral attributes in second-growth forest need evaluation for their efficacy in maintaining biodiversity, including complete forest-floor, small-mammal communities. Two common strategies in the Pacific Northwest are (1) management with thinnings to promote large trees with developed understories and (2) retention of legacies,...

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

    USDA-ARS?s Scientific Manuscript database

    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; (...

  13. 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.

  14. A reliable method of analyzing dietaries of mycophagous small mammals

    Treesearch

    W. Colgan; A.B. Carey; James M. Trappe

    1997-01-01

    Two methods of analyzing the dietaries of mycophagous small mammals were compared. Fecal pellets were collected from 11 northern flying squirrels and 12 Townsend's chipmunks, all caught live. In 1 method, pellets from each individual were examined microscopically; in the other, samples from 3 or 4 individuals from each species were pooled and the number of slides...

  15. Species-area and species-distance relationships of terrestrial mammals in the Thousand Island Region.

    PubMed

    Lomolino, Mark V

    1982-01-01

    The species-area and species-distance relationships of terrestrial mammals in the Thousand Island Region of the St. Lawrence River are totally consistent with the basic predictions of the equilibrium theory of island biogeography. The power model provides the best fit for the species-area relationship, and the z-value of 0.305 does not differ significantly from Preston's canonical value (0.26). Distance (D) is a normal determinant (Sαe -D (2)) of mammalian richness, and 93% of the variability in richness is accounted for by island area and isolation. The high z-values and poor species-distance correlations reported in previous studies of mammalian island biogeography, rather than evidencing non-equilibrium, are predictions consistent with the equilibrium theory for distant archipelagoes or, equivalently, poor immigrators such as mammals.

  16. 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.

  17. 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

  18. The effect of habitat patch size on small mammal populations

    Treesearch

    Mark D. Yates; Susan C. Loeb; David C. Guynn

    1997-01-01

    Habitat fragmentation is one of the greatest threats to the conservation of bio­diversity and has 3 components: habitat loss, patch isolation, and patch size. The authors tested the effects of forest-clearing size on small mammal populations in the Upper Coastal Plain of South Carolina. These clearings act as islands for many species of small mam­mals, particularly old...

  19. Effectiveness of protected areas for representing species and populations of terrestrial mammals in Costa Rica.

    PubMed

    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.

  20. 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

  1. 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

  2. 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.

  3. Differences in predatory pressure on terrestrial snails by birds and mammals.

    PubMed

    Rosin, Zuzanna M; Olborska, Paulina; Surmacki, Adrian; Tryjanowski, Piotr

    2011-09-01

    The evolution of shell polymorphism in terrestrial snails is a classic textbook example of the effect of natural selection in which avian and mammalian predation represents an important selective force on gene frequency. However, many questions about predation remain unclear, especially in the case of mammals. We collected 2000 specimens from eight terrestrial gastropod species to investigate the predation pressure exerted by birds and mice on snails. We found evidence of avian and mammalian predation in 26.5% and 36.8% of the shells. Both birds and mammals were selective with respect to snail species, size and morphs. Birds preferred the brown-lipped banded snail Cepaea nemoralis (L.) and mice preferred the burgundy snail Helix pomatia L. Mice avoided pink mid-banded C. nemoralis and preferred brown mid-banded morphs, which were neglected by birds. In contrast to mice, birds chose larger individuals. Significant differences in their predatory pressure can influence the evolution and maintenance of shell size and polymorphism of shell colouration in snails.

  4. 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

  5. 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

  6. 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.

  7. 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.

  8. Impact of mining and forest regeneration on small mammal biodiversity in the Western Region of Ghana.

    PubMed

    Attuquayefio, Daniel K; Owusu, Erasmus H; Ofori, Benjamin Y

    2017-05-01

    Much of the terrestrial biodiversity in sub-Saharan Africa is supported by tropical rainforest. Natural resource development, particularly surface mining in the rainforest, poses great risks to the region's rich and endemic biodiversity. Here, we assessed the impact of surface mining and the success of forest rehabilitation on small mammal diversity in the Western Region of Ghana. We surveyed small mammals in the project area and two adjoining forest reserves (control sites) before the mining operation and 10 years after mine closure and forest rehabilitation (topsoil replacement and revegetation). The forest reserves recorded higher species abundance than the mining areas. Majority of the species captured in the forest reserves, including Hylomyscus alleni, Praomys tullbergi, Malacomys cansdalei, and Hybomys trivirgatus, are forest obligate species. Only one individual each of H. alleni and P. tullbergi was captured in the naturally regenerated areas (core areas of mining activities that were allowed to revegetate naturally), while 32 individuals belonging to four species (Lophuromys sikapusi, Mus musculoides, Mastomys erythroleucus, and Crocidura olivieri) were recorded in the rehabilitated areas. Our data suggested negative effects of mining on small mammal diversity and the restoration of species diversity and important ecological processes after rehabilitation of altered habitats. We strongly encourage deliberate conservation efforts, particularly the development of management plans that require the restoration of degraded land resulting from mining activities.

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 50 CFR 18.27 - Regulations governing small takes of marine mammals incidental to specified activities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... marine mammals incidental to specified activities. 18.27 Section 18.27 Wildlife and Fisheries UNITED... MAMMALS General Exceptions § 18.27 Regulations governing small takes of marine mammals incidental to...) of the Marine Mammal Protection Act of 1972, as amended, 16 U.S.C. 1371(a)(5), which provides a...

  15. 50 CFR 18.27 - Regulations governing small takes of marine mammals incidental to specified activities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... marine mammals incidental to specified activities. 18.27 Section 18.27 Wildlife and Fisheries UNITED... MAMMALS General Exceptions § 18.27 Regulations governing small takes of marine mammals incidental to...) of the Marine Mammal Protection Act of 1972, as amended, 16 U.S.C. 1371(a)(5), which provides a...

  16. Predicting above-ground density and distribution of small mammal prey species at large spatial scales

    Treesearch

    Lucretia E. Olson; John R. Squires; Robert J. Oakleaf; Zachary P. Wallace; Patricia L. Kennedy

    2017-01-01

    Grassland and shrub-steppe ecosystems are increasingly threatened by anthropogenic activities. Loss of native habitats may negatively impact important small mammal prey species. Little information, however, is available on the impact of habitat variability on density of small mammal prey species at broad spatial scales. We examined the relationship between small mammal...

  17. Small mammal populations in a grazed and ungrazed riparian habitat in Nevada

    Treesearch

    Dean E. Medin; Warren P. Clary

    1989-01-01

    Small mammal populations were compared between a grazed habitat and a comparable adjoining habitat protected from grazing by an exclosure. Composition, naive densiiy, standing crop biomass, species diversity, and other attributes of the small mammal communities were assessed. More species and higher numbers of most small mammals were found in the ungrazed habitat....

  18. Small mammal distributions relative to corridor edges within intensively managed southern pine plantations.

    Treesearch

    Nicole L. Constantine; Tyler A. Campbell; William M. Baughman; Timothy B. Harrington; Brian R. Chapman; Karl V. Miller

    2005-01-01

    We characterized small mammal communities in three loblolly pine (Pinus taeda) stands in the Lower Coastal Plain of South Carolina during June 1998-Aug. 2000 to investigate influence of corridor edges on small mammal distribution. We live-trapped small mammals in three regenerating stands following clearcutting. Harvested stands were bisected by...

  19. A reconnaissance of small mammal communities in Garland and Government prairies, Arizona

    Treesearch

    Joseph L. Ganey; Carol L. Chambers

    2011-01-01

    Small mammals play key ecological roles in grassland ecosystems, yet little is known regarding small mammal communities in large (>50 km2), high-elevation prairies embedded in ponderosa pine (Pinus ponderosa) forests in north central Arizona. To provide information on community composition and habitat relationships, we live-trapped small mammals on 6 transects in 2...

  20. Small mammal populations and ecology in the Kings River Sustainable Forest Ecosystems Project area

    Treesearch

    William F. Jr. Laudenslayer; Roberta J. Fargo

    2002-01-01

    Small mammals are important components of woodlands and forests. Since 1992, we have been studying several aspects of small mammal ecology in oak woodlands in western foothills of the southern Sierra Nevada. Assemblages of small, nocturnal mammal species are dominated by the brush mouse (Peromyscus boylii), California mouse (P. californicus...

  1. Small mammals of the Bitterroot National Forest: Ecological significance and guidelines for management

    Treesearch

    Dean E. Pearson

    2000-01-01

    Small mammal literature was reviewed to assess the ecological role of small mammals on the Bitterroot National Forest of western Montana. Small mammals fulfill numerous important roles in forest ecosystems by supporting a wide range of predators, dispersing seeds and mycorrhizal spores, altering vegetation through herbivory and seed predation, and preying on insects....

  2. Non-target captures during small mammal trapping with snap traps

    Treesearch

    David G. Peitz; Philip A. Tappe; Ronald E. Thill; Roger W. Perry; M. Anthony Melchiors; T. Bently Wigley

    2001-01-01

    There is little published information available on non-target captures during small mammal trapping. We used a variety of snap traps baited with a rolled oat-peanut butter mix to capture 2,054 individuals from 9 genera of small mammals in a study of small mammal and avian community structure in riparian areas and adjacent loblolly pine (Pinus taeda) plantations. We...

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. ATLANTIC-CAMTRAPS: a dataset of medium and large terrestrial mammal communities in the Atlantic Forest of South America.

    PubMed

    Lima, Fernando; Beca, Gabrielle; de Lara Muylaert, Renata; Jenkins, Clinton N; Perilli, Miriam Lucia Lages; de Oliveira Paschoal, Ana Maria; Massara, Rodrigo Lima; Paglia, Adriano Pereira; Chiarello, Adriano Garcia; Graipel, Maurício Eduardo; Cherem, Jorge José; Regolin, André Luis; Oliveira Santos, Luiz Gustavo Rodrigues; Brocardo, Carlos Rodrigo; Paviolo, Agustín; Di Bitetti, Mario S; Scoss, Leandro Moraes; Rocha, Fabiana Lopes; Fusco-Costa, Roberto; Rosa, Clarissa Alves da; da Silva, Marina Xavier; Hufnagel, Ludmila; Santos, Paloma Marques; Duarte, Gabriela Teixeira; Guimarães, Luiza Neves; Bailey, Larissa Lynn; Guimarães Rodrigues, Flávio Henrique; Cunha, Heitor Morais; Moreli Fantacini, Felipe; Batista, Graziele Oliveira; Bogoni, Juliano André; Tortato, Marco Adriano; Luiz, Micheli Ribeiro; Peroni, Nivaldo; de Castilho, Pedro Volkmer; Maccarini, Thiago Bernardes; Picinatto Filho, Vilmar; De Angelo, Carlos; Cruz, Paula; Quiroga, Verónica; Iezzi, María Eugenia; Varela, Diego; Cavalcanti, Sandra Maria Cintra; Martensen, Alexandre Camargo; Maggiorini, Erica Vanessa; Keesen, Fabíola Ferreira; Valle Nunes, André; Lessa, Gisele Mendes; Cordeiro-Estrela, Pedro; Beltrão, Mayara Guimarães; de Albuquerque, Anna Carolina Figueiredo; Ingberman, Bianca; Cassano, Camila Righetto; Junior, Laury Cullen; Ribeiro, Milton Cezar; Galetti, Mauro

    2017-08-31

    Our understanding of mammal ecology has always been hindered by the difficulties of observing species in closed tropical forests. Camera trapping has become a major advance for monitoring terrestrial mammals in biodiversity rich ecosystems. Here we compiled one of the largest datasets of inventories of terrestrial mammal communities for the Neotropical region based on camera trapping studies. The dataset comprises 170 surveys of medium to large terrestrial mammals using camera traps conducted in 144 areas by 74 studies, covering six vegetation types of tropical and subtropical Atlantic Forest of South America (Brazil and Argentina), and present data on species composition and richness. The complete dataset comprises 53,438 independent records of 83 species of mammals, includes 10 species of marsupials, 15 rodents, 20 carnivores, 8 ungulates and 6 armadillos. Species richness averaged 13 species (± 6.07 SD) per site. Only six species occurred in more than 50% of the sites: the domestic dog Canis familiaris, crab-eating fox Cerdocyon thous, tayra Eira barbara, south American coati Nasua nasua, crab-eating raccoon Procyon cancrivorus and the nine-banded armadillo Dasypus novemcinctus. The information contained in this dataset can be used to understand macroecological patterns of biodiversity, community, and population structure, but also to evaluate the ecological consequences of fragmentation, defaunation, and trophic interactions. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. A comparison of bottles and snap traps for short-term small mammal sampling

    Treesearch

    James F. Taulman; Ronald E. Thill; T. Bently Wigley; M. Anthony Melchiors

    1992-01-01

    Bottles were tested as traps for small mammals. Used in conjunction with three types of snap traps over 30,240 trap nights, bottles captured eight (2%) of the total 421 mammals taken. Bottles were inefficient in capturing small mammals compared to snap traps.

  14. 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.

  15. 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.

  16. Postnatal long bone growth in terrestrial placental mammals: allometry, life history, and organismal traits.

    PubMed

    Kilbourne, Brandon M; Makovicky, Peter J

    2012-10-01

    The ontogenetic allometry of long bone proportions is poorly understood in Mammalia. It has previously been suggested that during mammalian ontogeny long bone proportions grow more slender (positive allometry; length ∝ circumference(>1.0) ), although this conclusion was based upon data from a few small-bodied taxa. It remains unknown how ontogenetic long bone allometry varies across Mammalia in terms of both taxonomy and body size. We collected long bone length and circumference data for ontogenetic samples of 22 species of mammals spanning six major clades and three orders of magnitude in body mass. Using reduced major axis bivariate regressions to compare bone length to circumference, we found that isometry and positive allometry are the most widespread patterns of growth across mammals. Negative allometry (i.e., bones growing more robust during ontogeny) occurs in mammals but is largely restricted to cetartiodactyls. Using regression slope as a proxy for long bone allometry, we compared long bone allometry to life history and organismal traits. Neonatal body mass, adult body mass, and growth rate have a negative relationship with long bone allometry. At an adult mass of roughly 15-20 kg, long bone growth shifts from positive allometry to mainly isometry and negative allometry. There were no significant relationships between ontogenetic long bone allometry and either cursoriality or basal metabolic rate. Copyright © 2012 Wiley Periodicals, Inc.

  17. 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.

  18. 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.

  19. 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

  20. 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

  1. 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

  2. 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.

  3. 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

  4. 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

  5. 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.

  6. 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.

  7. Influence of Feeding and Body Mass on IUCN Extinction Threat of Extant Marine and Terrestrial Mammals

    NASA Astrophysics Data System (ADS)

    Lam, G.; Wang, I. M.; Heim, N.; Payne, J.

    2016-12-01

    Extinction is a fundamental phenomenon that has been occurring for millions of years and is critical to the development of new organisms and niches. However, the current extinction rate is now one hundred to a thousand times the past background extinction rate due to human influences and rapidly changing environments. Research on geographic range and life history has been performed in extinction analyses, but rarely any on feeding type and trophic level. We compiled data from the IUCN Red List Database, Paleobiology database and diets from Pauly et al. (1998) to explore the possible correlation between various aspects of ecology and extinction threat. By doing so, we can better understand where to focus our conservation efforts, and what type of approach will reap the best results. We discovered that terrestrial carnivores are slightly less at risk than herbivores and omnivores, and that the feeding and tiering of marine mammals have minimal effect on their IUCN threat level. Body mass is the most influential factor on risk level, with larger adult body masses being most at risk.

  8. 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.

  9. 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.

  10. 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

  11. Phylogenetic analysis of conservation priorities for aquatic mammals and their terrestrial relatives, with a comparison of methods.

    PubMed

    May-Collado, Laura J; Agnarsson, Ingi

    2011-01-01

    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. 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. 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--and thus 'biodiverse'--species are faring relatively poorly is alarming

  12. Future directions in training of veterinarians for small exotic mammal medicine: expectations, potential, opportunities, and mandates.

    PubMed

    Rosenthal, Karen

    2006-01-01

    Small exotic mammals have been companions to people for almost as long as dogs and cats have been. The challenge for veterinary medicine today is to decipher the tea leaves and determine whether small mammals are fad or transient pets or whether they will still be popular in 20 years. This article focuses on pet small-mammal medicine, as the concerns of the laboratory animal are better known and may differ profoundly from those of a pet. Dozens of species of small exotic mammals are kept as pets. These pet small-mammal species have historically served human purposes other than companionship: for hunting, for their pelts, or for meat. Now, they are common pets. At present, most veterinary schools lack courses in the medical care of these animals. Veterinary students need at least one required class to introduce them to these pets. Currently, there are no small-mammal-only residency programs. This does not correspond with current needs. The only way to judge current needs is by assessing what employers are looking for. In a recent JAVMA classified section, almost 30% of small-animal practices in suburban/urban areas were hiring veterinarians with knowledge of exotic pets. All veterinarians must recognize that pet exotic small mammals have changed the landscape of small-animal medicine. It is a reality that, today, many small-animal practices see pet exotic small mammals on a daily basis.

  13. 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

  14. 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. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. 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.

  16. 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

  17. 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.

  18. Experimental analysis of methods for measuring small mammal populations

    USGS Publications Warehouse

    Stickel, L.F.

    1946-01-01

    SUMMARY: The Peromyscus leucopus on a 17-acre study area were live-trapped, marked, and released over a seven-day period. On the three following nights intensive snap-trapping was done on the central acre of the study plot. The animals caught by snap traps in the central acre represented the population of the central acre and several surrounding acres. By the currently accepted methods of interpreting snap-trap data, the population per acre would be considered to be 23 adults. The live-trap data show that the true population was between six and seven adults per acre. Modern methods of live-trapping are shown to be valid for population studies. Two methods are presented for the conversion of live-trap data into per acre figures. Errors involved in the current use of snap-trap data are discussed and snap-trap methods are shown to be invalid for determining actual population numbers. It should be practical to use a snap-trap quadrant technique to obtain a relative measure or index figure for small mammal populations.

  19. 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.

  20. Trap-induced mass declines in small mammals: Mass as a population index

    Treesearch

    Dean E. Pearson; Yvette K. Ortega; Leonard F. Ruggiero

    2003-01-01

    Body mass is routinely used as an index of physical condition for comparing small-mammal populations. However, trapping effects on animals may undermine the effectiveness of body mass as an index of population health. We examined the effects of live-trapping on body mass of 3 small-mammal species: deer mice (Peromyscus maniculatus), southern red-...

  1. Responses of small mammals to coarse woody debris in a southeastern pine forest

    Treesearch

    Susan C. Loeb

    1999-01-01

    The importance of coarse woody debris (CWD) to small mammals in a managed pine forest in South Carolina was tested experimentally during summer and autumn 1990 and winter and spring 1991-1994. Abundance and demographics of small mammals were compared between plots with abundant CWD created by a tornado (unsalvaged plots) and plots where tornado-created CWD had been...

  2. Small mammal communities and habitat selection in Northern Rocky Mountain bunchgrass: Implications for exotic plant invasions

    Treesearch

    Dean E. Pearson; Yvette K. Ortega; Kevin S. McKelvey; Leonard F. Ruggiero

    2001-01-01

    Agriculture and development have dramatically reduced the range of native bunchgrass habitats in the Northern Rocky Mountains, and the invasion of exotic plants threatens to greatly alter the remaining pristine prairie. Small mammals play many important roles in ecosystem functions, but little is known about small mammal community composition and structure in native...

  3. Using thinning as a management tool for gypsy moth: the influence on small mammal abundance

    Treesearch

    R.M. Muzika; S.T. Grushecky; A.M. Liebhold; R.L. Smith

    2004-01-01

    Silvicultural manipulations may be used to reduce forest susceptibility or vulnerability to defoliation by the gypsy moth. The effects of this management strategy on small mammal abundance were determined by pitfall trapping small mammals 1 year before silvicultural thinnings and for 3 years following thinning in a deciduous montane forest. Sorex cinereus...

  4. Small Mammal Communities of Mature Pine Hardwood Stands in the Ouachita Mountains

    Treesearch

    Phillip A. Tappe; Ronald E. Thill; Joseph J. Krystofik; Gary A. Heidt

    1994-01-01

    A study was conducted on the Ouachita and Ozark National Forests in Arkansas to evaluate the effects of alternative pine-hardwood reproduction cutting methods on small mammal abundance and diversity. Pretreatment characteristics of small mammal communities on 20 late-rotation mixed pine-hardwood stands in four physiographic zones of the Ouachita Mountain region of...

  5. Climatic variation modulates the indirect effects of large herbivores on small-mammal habitat use.

    PubMed

    Long, Ryan A; Wambua, Alois; Goheen, Jacob R; Palmer, Todd M; Pringle, Robert M

    2017-07-01

    Large mammalian herbivores (LMH) strongly shape the composition and architecture of plant communities. A growing literature shows that negative direct effects of LMH on vegetation frequently propagate to suppress the abundance of smaller consumers. Indirect effects of LMH on the behaviour of these consumers, however, have received comparatively little attention despite their potential ecological significance. We sought to understand (i) how LMH indirectly shape small-mammal habitat use by altering the density and distribution of understorey plants; (ii) how these effects vary with climatic context (here, seasonality in rainfall); and (iii) the extent to which behavioural responses of small mammals are contingent upon small-mammal density. We tested the effects of a diverse LMH community on small-mammal habitat use using 4 years of spatially explicit small-mammal trapping and vegetation data from the UHURU Experiment, a replicated set of LMH exclosures in semi-arid Kenyan savanna. Small-mammal habitat use was positively associated with tree density and negatively associated with bare (unvegetated) patches in all plots and seasons. In the presence of LMH, and especially during the dry season, small mammals consistently selected tree cover and avoided bare patches. In contrast, when LMH were excluded, small mammals were weakly associated with tree cover and did not avoid bare patches as strongly. These behavioural responses of small mammals were largely unaffected by changes in small-mammal density associated with LMH exclusion. Our results show that LMH indirectly affect small-mammal behaviour, and that these effects are influenced by climate and can arise via density-independent mechanisms. This raises the possibility that anthropogenic LMH declines might interact with changing patterns of rainfall to alter small-mammal distribution and behaviour, independent of numerical responses by small mammals to these perturbations. For example, increased rainfall in East

  6. 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. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. 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

  8. 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

  9. 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

  10. A long-lasting wireless stimulator for small mammals.

    PubMed

    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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. Small mammals in managed, naturally young, and old-growth forests.

    Treesearch

    A.B. Carey; M.L. Johnson

    1995-01-01

    Forest managers in the Pacific Northwest are faced with new challenges of providing for all wildlife in managed forests. Our objective was to elucidate the factors governing the composition and biomass of forest floor mammal communities that are amenable to management. We sampled small mammal communities in forests of various management histories on the Olympic...

  17. 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. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  18. Small-mammal responses to pine regeneration treatments in the Ouachita Mountains of Arkansas and Oklahoma, USA

    Treesearch

    Roger W. Perry; Ronald E. Thill

    2005-01-01

    We compared the initial effects of four forest regeneration treatments (single-tree selection, group selection, shelterwood, and clearcut), and unharvested controls (mature, second-growth forest) on relative abundance of small mammals and small-mammal habitat throughout the Ouachita Mountains of western Arkansas and eastern Oklahoma. We compared small-mammal capture...

  19. 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.

  20. 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.

  1. Habitat associations of small mammals in southern Brazil and use of regurgitated pellets of birds of prey for inventorying a local fauna.

    PubMed

    Scheibler, D R; Christoff, A U

    2007-11-01

    We inventoried terrestrial small mammals in an agricultural area in southern Brazil by using trapping and prey consumed by Barn Owls (Tyto alba) and White-tailed Kites (Elanus leucurus). Small mammals were trapped in three habitat types: corn fields, uncultivated fields ("capoeiras"), and native forest fragments. A total of 1,975 small mammal specimens were trapped, another 2,062 identified from the diet of Barn Owls, and 2,066 from the diet of White-tailed Kites. Both trapping and prey in the predators' diet yielded 18 small mammal species: three marsupials (Didelphis albiventris, Gracilinanus agilis, and Monodelphis dimidiata) and 15 rodents (Akodon paranaensis, Bruceppatersonius iheringi, Calomys sp., Cavia aperea, Euryzygomatomys spinosus, Holochilus brasiliensis, Mus musculus, Necromys lasiurus, Nectomys squamipes, Oligoryzomys nigripes, Oryzomys angouya, Oxymycterus sp.1, Oxymycterus sp.2, Rattus norvegicus, and Rattus rattus (Linnaeus, 1758)). The greatest richness was found in the uncultivated habitat. We concluded that the three methods studied for inventorying small mammals (prey in the diet of Barn Owls, White-tailed Kites, and trapping) were complementary, since together, rather than separately, they produced a better picture of local richness.

  2. 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.

  3. 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)

  4. 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) ...

  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. 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

  7. 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.

  8. 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)

  9. 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) ...

  10. 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.

  11. 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.

  12. 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.

  13. Untangling the roles of fire, grazing and rainfall on small mammal communities in grassland ecosystems.

    PubMed

    Yarnell, R W; Scott, D M; Chimimba, C T; Metcalfe, D J

    2007-11-01

    In grassland systems across the globe, ecologists have been attempting to understand the complex role of fire, grazing and rainfall in creating habitat heterogeneity and the consequences of anthropogenic control of these factors on ecosystem integrity and functioning. Using a South African grassland ecosystem as a model, we investigated the impact of fire and grazing pressure on small mammal communities during three differing periods of a rainfall cycle. Over 2 years, 15,203 trap nights revealed 1598 captures of 11 species (nine rodents, one macroscelid and one insectivore). Results highlighted the importance of the interplay between factors and showed that the role of fire, grazing and rainfall in determining small mammal abundance was species-dependant. While no two species were affected by the same environmental variables, grass cover or height was important to 56% of species. Considered independently, high rainfall had a positive influence on small mammal abundance and diversity, although the lag period in population response was species-specific. High grazing negatively affected overall abundance, but specifically in Mastomys coucha; fire alone had little immediate impact on small mammal diversity. Six months after the fire, vegetation cover had recovered to similar levels as unburned areas, although small mammal diversity and richness were higher in burned areas than unburned areas. Grazing levels influenced the rate of vegetation recovery. In conclusion, low-level grazing and burning can help to maintain small mammal biodiversity, if conducted under appropriate rainfall levels. A too high grazing pressure, combined with fire, and/or fire conducted under drought conditions can have a negative impact on small mammal biodiversity. To maintain small mammal diversity in grassland ecosystems, the combined effects of the previous year's rainfall and existing population level as well as the inhibition of vegetation recovery via grazing pressure need to be taken into

  14. Sampling small mammals in southeastern forests: the importance of trapping in trees

    Treesearch

    Susan C. Loeb; Gregg L. Chapman; Theodore R. Ridley

    2001-01-01

    Because estimates of small mammal species richness and diversity are strongly influenced by sampling methodology, 2 or more trap types are often used in studies of small mammal communities. However, in most cases, all traps are placed at ground level. In contrast, we used Sherman live traps placed at 1.5 m in trees in addition to Sherman live traps and Mosby box traps...

  15. 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

  16. 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).

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Inventory of terrestrial mammals in the Rincon Mountains using camera traps

    Treesearch

    Don E. Swann; Nic Perkins

    2013-01-01

    The Sky Island region of the southwestern United States and northwestern Mexico is well-known for its diversity of mammals, including endemic species and species representing several different biogeographic provinces. Camera trap studies have provided important insight into mammalian distribution and diversity in the Sky Islands in recent years, but few studies have...

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

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

    USGS Publications Warehouse

    Wiewel, A.S.; Clark, William R.; Sovada, Marsha 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.

  14. Initial small mammal responses to alternative pine regeneration methods in Arkansas and Oklahoma: preliminary findings

    Treesearch

    Ronald E. Thill; Roger W. Perry; Nancy E. Koerth; Philip A. Tappe; David G. Peitz

    2004-01-01

    Abstract - We studied winter small mammal communities in the Ouachita Mountains of west-central Arkansas and eastern Oklahoma using Sherman live traps in four replications of four regeneration treatments (clearcut/plant, shelterwood, single-tree selection, and group selection), plus four mature, untreated "controls." Data on relative small...

  15. A pre-treatment assessment of small mammals in the hardwood ecosystem experiment

    Treesearch

    Natasha A. Urban; Robert K. Swihart

    2013-01-01

    The Hardwood Ecosystem Experiment (HEE) is a 100-year, replicated experiment implemented in south-central Indiana to examine the impacts of multiple timber management regimes on forest ecosystems. A secondary objective of the HEE is to evaluate responses of small mammal assemblages. We trapped at 32 sites prior to silvicultural treatments to assess pre-treatment small...

  16. 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

  17. Montana Evidence for Extra-Terrestrial Impact Event That Caused Ice-Age Mammal Die- Off

    NASA Astrophysics Data System (ADS)

    Baker, D. W.; Miranda, P. J.; Gibbs, K. E.

    2008-05-01

    Evidence has been found in Montana for an extra-terrestrial impact event previously documented in the States of AZ, NM, NC, and SC and in Alberta and Manitoba. A mammoth fossil site dated at 11.5 ka (C14) before present (BP) was described in 1969 as the last mammoth occurrence in Montana. The mammoth remains were found in an organic-rich layer--a black mat. The black mat contains abundant charcoal (evidence for forest fire), black carbon glass foam, plant material deposited in a pond, and unrusted iron micro-meteorites. SEM photos of iron micro-meteorites reveal fusion crusts, flow lines, and micro-impact craters--direct evidence for an extra- terrestrial origin. One 140 μm long micro-meteorite is 96 wt.% Fe and 4% Mn. Another is 71% Fe and 29% Ti. Mammoth tusks contain rusty pits, consistent with iron micro-meteorites that were embedded and then rusted out. A sample of carbon glass in the black mat contains 62% C, 22% O, 6% Fe, 4% Ca, 4% Si, and 2% Al. At the Indian Creek Archeological Site near Townsend, MT below the cultural layers and below a 11.2 ka (C14) volcanic ash layer there are individual glass bubbles about 1 mm in diameter with micro-impact craters. The size distribution of these micro-craters resembles the size distribution of lunar craters, but at a vastly different scale. The glass contains 53% C, 33% O, 6% Ca, 4% Si, 2% Al, 1% Mg, and 0.6% K. The carbon glass and micro-meteorites suggest a comet rather a meteorite origin for the extra-terrestrial material.

  18. 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.

  19. 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

  20. 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

  1. 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.

  2. 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%.

  3. A framework for assessment and monitoring of small mammals in a lowland tropical forest.

    PubMed

    Solari, Sergio; Rodriguez, Juan José; Vivar, Elena; Velazco, Paul M

    2002-05-01

    Development projects in tropical forests can impact biodiversity. Assessment and monitoring programs based on the principles of adaptive management assist managers to identify and reduce such impacts. The small mammal community is one important component of a forest ecosystem that may be impacted by development projects. In 1996, a natural gas exploration project was initiated in a Peruvian rainforest. The Smithsonian Institution's Monitoring and Assessment of Biodiversity program cooperated with Shell Prospecting and Development Peru to establish an adaptive management program to protect the region's biodiversity. In this article, we discuss the role of assessing and monitoring small mammals in relation to the natural gas project. We outline the conceptual issues involved in establishing an assessment and monitoring program, including setting objectives, evaluating the results and making appropriate decisions. We also summarize the steps taken to implement the small mammal assessment, provide results from the assessment and discuss protocols to identify appropriate species for monitoring.

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

    USGS Publications Warehouse

    Flickinger, Edward L.; Nichols, J.D.

    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.

  5. Relation between small-mammal species composition and anthropic variables in the Brazilian Atlantic Forest.

    PubMed

    Olifiers, N; Gentile, R; Fiszon, J T

    2005-08-01

    Anthropic activities are frequently related in many ways to forest fragmentation and alteration of natural communities. In this study, we correlate the presence of hunting, tourism activity, agriculture/pasturing, and the distance of the study sites to the nearest human residences with the species composition of small Atlantic forest mammals. To do this, we utilize a multiple regression analysis of similarity matrices. The presence of both agriculture/pasturing and human residences near the study sites proved to be determinant factors in species composition of small mammals of the studied areas. Working with socioeconomic variables related directly with the study site could be a reliable and a direct way to predict the influence of human presence and entailed activity on small mammal communities.

  6. 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.

  7. Small Mammals as Indicators of Climate, Biodiversity, and Ecosystem Change

    USGS Publications Warehouse

    Hope, Andrew G.; Waltari, Eric; Morse, Nathan R.; Flamme, M.J.; Cook, Joseph A.; Talbot, Sandra

    2017-01-01

    Climate is a driving evolutionary force for biodiversity in high-latitude Alaska. This region is complex and dynamic with high annual variation in temperature and light. Through deeper time, Alaska has experienced major climate extremes over much longer periodicity. For example, the Quaternary Period (the last ~2.5 million years), commonly known as the Ice Age, was punctuated by more than 20 major glacial-interglacial cycles. During glacial phases, water was locked up in ice sheets that covered much of North America, and the resulting lower sea levels exposed a land connection between Alaska and Siberia, a combined region known as Beringia (Figure 1). This isthmus provided vast expanses of land for species to inhabit, provided they could withstand potentially harsh polar conditions. Each extended glacial phase periodically transitioned into a shorter interglacial warm phase. These climate reversals melted continental ice sheets to expose corridors for reinvasion of terrestrial species, particularly those associated with forested habitats further south. Those species that survived at northern latitudes through repeated glacial-interglacial cycles formed the Arctic tundra communities that persist today. At present, Alaska supports diverse communities associated with both tundra and forests (Figure 2). These communities often interact with one another across latitudinal and elevational gradients, with tundra species generally found further north or higher in elevation. Alaska’s climate is continuing to change today, strongly influencing local environments and the distribution and dynamics of wildlife species.

  8. 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.

  9. 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

  10. 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. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. Bioaccumulation of metals and effects of a landfill in small mammals. Part II. The wood mouse, Apodemus sylvaticus.

    PubMed

    Sánchez-Chardi, Alejandro; Peñarroja-Matutano, Cristina; Ribeiro, Ciro Alberto Oliveira; Nadal, Jacint

    2007-11-01

    We assess the bioaccumulation of metals (Pb, Hg, Cd, Fe, Mg, Zn, Cu, Mn, Mo, Cr) and effects of landfill leachates on morphological (RI, relative weights), plasma (GPT, GOT, creatinine), and genotoxic (MNT) parameters in wood mice, Apodemus sylvaticus, inhabiting close the Garraf landfill site (NE Spain). Due to the high age- and sex-dependent variation in wild populations, we also studied the effect of these biotic factors on the parameters studied. Wood mice from the landfill site, sited in a partially protected area, showed more Cd, Fe, Zn, Cu, Mn, Mo, and Cr than specimens from the reference site. Moreover, mice near the landfill registered low RI and high relative renal weight, GPT, and MN frequency, which indicate that the landfill affects the health of wild mice. In contrast to sympatric shrews from a previous study, wood mice showed lower bioaccumulation of metals and lower variation caused by biotic factors. Moreover, the morphological and physiological alterations demonstrated that they were also more sensitive at environmental pollution. Given the contribution of small mammals to ecosystem function and the scarce ecotoxicological data on the effects of landfill pollution on wild terrestrial mammals, we consider that our study can be used to improve the management of this protected area.

  3. Vegetation patterns and abundances of amphibians and small mammals along small streams in a northwestern California watershed

    Treesearch

    Jeffrey R. Waters; Cynthia J. Zabel; Kevin S. McKelvey; Hartwell H. Welsh

    2001-01-01

    Our goal was to describe and evaluate patterns of association between stream size and abundances of amphibians and small mammals in a northwestern California watershed. We sampled populations at 42 stream sites and eight upland sites within a 100- watershed in 1995 and 1996. Stream reaches sampled ranged from poorly defined channels that rarely flowed to 10-m-wide...

  4. Small mammal habitat associations in poletimber and sawtimber stands of four forest cover types

    Treesearch

    Richard M. DeGraaf; Dana P. Snyder; Barbara J. Hill

    1991-01-01

    Small mammal distribution was examined in poletimber and sawtimber stands of four forest cover types in northern New England: northern hardwoods, red maple, balsam fir, and red spruce-balsam fir. During 1980 and 1981, eight stands on the White Mountain National Forest, NH, were sampled with four trap types (three sizes of snap traps and one pit-fall) for 16 000 trap-...

  5. Diversity of small mammals in the Sierra Nevada: Filtering by natural selection or by anthropogenic activities?

    Treesearch

    Douglas A. Kelt; Rahel Sollmann; Angela M. White; Susan L. Roberts; Dirk H. Van Vuren

    2016-01-01

    Both historical and contemporary factors may influence the structure and composition of biotas. Small mammal faunas in the Sierra Nevada of California, United States, are strongly dominated by generalist species; however, whereas 1 recent study argues that this is a product of recent anthropogenic influences, another provides a deeper evolutionary explanation based on...

  6. 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.

  7. 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.

  8. Effects of wildfire severity on small mammals in northern Arizona ponderosa pine forests

    Treesearch

    Sean C. Kyle; William M. Block

    2000-01-01

    We examined effects of a varied-severity wildfire on the community structure of small mammals and populations of the 2 most abundant species, the deer mouse (Peromyscus maniculatus) and the gray-collared chipmunk (Tamias cinereicollis), in northern Arizona ponderosa pine (Pinus ponderosa) forests. We examined 2...

  9. Development and evaluation of habitat models for herpetofauna and small mammals

    Treesearch

    William M. Block; Michael L. Morrison; Peter E. Scott

    1998-01-01

    We evaluated the ability of discriminant analysis (DA), logistic regression (LR), and multiple regression (MR) to describe habitat use by amphibians, reptiles, and small mammals found in California oak woodlands. We also compared models derived from pitfall and live trapping data for several species. Habitat relations modeled by DA and LR produced similar results,...

  10. 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...

  11. 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 ...

  12. 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.

  13. Incidental captures of birds in small mammal traps: a cautionary note for interdisciplinary studies.

    Treesearch

    David L. Waldien; Miranda M. Cooley; Jennifer Weikel; John P. Hayes; Chris C. Maguire; Tom Manning; Thomas J. Maier

    2004-01-01

    Although benefits of interdisciplinary studies are numerous, potential exists for data acquisition for some aspects of such studies to impact data acquisition for other aspects. This may be particularly true in studies involving both trapping of small mammals and assessment of bird populations. We summarize the incidence of birds captured during 8 research projects in...

  14. 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...

  15. Rickettsial infections of fleas collected from small mammals on four islands in Indonesia.

    PubMed

    Barbara, Kathryn A; Farzeli, Arik; Ibrahim, Ima N; Antonjaya, Ungke; Yunianto, Andre; Winoto, Imelda; Ester; Perwitasari, Dian; Widjaya, Susana; Richards, Allen L; Williams, Maya; Blair, Patrick J

    2010-11-01

    Ectoparasites were sampled from small mammals collected in West Java, West Sumatra, North Sulawesi, and East Kalimantan, Indonesia, in 2007-2008 and were screened for evidence of infection from bacteria in the Rickettsaceae family. During eight trap nights at eight sites, 208 fleas were collected from 96 of 507 small mammals trapped from four orders (379 Rodentia; 123 Soricomorpha; two Carnivora; three Scandentia). Two species of fleas were collected: Xenopsylla cheopis (n = 204) and Nosopsyllus spp. (n = 4). Among the 208 fleas collected, 171 X. cheopis were removed from rats (Rattus spp.) and 33 X. cheopis from shrews (Suncus murinus). X. cheopis were pooled and tested for DNA from rickettsial agents Rickettsia typhi, Rickettsia felis, and 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 detected in a pool of X. cheopis collected from an animal in East Kalimantan. Sixteen percent of the X. cheopis pools were found positive for Rickettsia spp.; four (10.8%) R. typhi, one (2.7%) R. felis, and one (2.7%) codetection of R. felis and a spotted fever group rickettsia. These data suggest that rickettsial infections remain a threat to human health across Indonesia.

  16. 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...

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

    USDA-ARS?s Scientific Manuscript database

    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...

  18. 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...

  19. Riparian and upland small mammals on the east slope of the Cascade Range, Washington

    Treesearch

    John F. Lehmkuhl; Roger D. Peffer; Margaret A. O' Connell

    2008-01-01

    Differences in small mammal diversity and abundance between riparian and upland areas have not been consistently shown in the Pacific Northwest, and the issue is expected to be complex along the east slope of the Cascade Range with its complex biogeography and forest landscape structure. The information is important for evaluating buffer zone management and the...

  20. The Effect of Riparian Zones in Structuring Small Mammal Communities in the Southern Appalachians

    Treesearch

    Joshua Laerm; Michael A. Menzel; Dorothy J. Wolf; James R. Welch

    1997-01-01

    Riparian zones have been shown to be important in structuring vertebrate communities and in maintaining biodiversity. We examined the role of riparian zones in structuring small mammal communities in a southern Appalachian watershed at Coweeta Hydrological Laboratory, Macon County, North Carolina. We established pitfall and live-trap grids in three replicates each of...

  1. 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...

  2. 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...

  3. 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 ...

  4. Effects of a Community Restoration Fire on Small Mammals and Herpetofauna in the Southern Appalachains

    Treesearch

    William M. Ford; M. Alex Menzel; David W. McGill; Joshua Laerm; Timothy S. McCay

    1999-01-01

    As part of the Wine Spring Creek ecosystem management project on the Nantahala National forest, North Carolina, we assessed effects of a community restoration fire on small mammals and herpetofauna in the upper slope pitch pine (Pinus rigida) stands, neighboring midslope oak (Quercus spp.) stands and rhododendron (...

  5. The value of Rocky Mountain juniper (Juniperus scopulorum) woodlands in South Dakota as small mammal habitat

    Treesearch

    Carolyn Hull Sieg

    1988-01-01

    Small mammals and vegetation were sampled over two years in Rocky Mountain juniper woodlands and adjacent grasslands in South Dakota. Juniper woodlands provided specialized habitat for two woodland species, white-footed mice and bushy-tailed woodrats, and attracted a number of species generally associated with grasslands.

  6. Small mammal communities of streamside management zones in intensively managed pine forests of Arkansas

    Treesearch

    Darren A. Miller; Ronald E. Thill; M. Anthony Melchiors; T. Bently Wigley; Philip A. Tappe

    2004-01-01

    Streamside management zones (SMZs), composed primarily of hardwoods in the southeastern United States, provide habitat diversity within intensively managed pine (Pinus spp.) plantations. However, effects of SMZ width and adjacent plantation structure on riparian wildlife communities are poorly understood. Therefore, during 1990-1995, we examined small mammal...

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

    Treesearch

    Travis M. Hinkelman; John L. Orrock; Susan C Loeb

    2011-01-01

    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 giving-up densities to quantify...

  8. Transect versus grid trapping arrangements for sampling small-mammal communities

    Treesearch

    Dean E. Pearson; Leonard F. Ruggiero

    2003-01-01

    We compared transect and grid trapping arrangements for assessing small-mammal community composition and relative abundance for 2 years in 2 forest cover types in west-central Montana, USA. Transect arrangements yielded more total captures, more individual captures, and more species than grid arrangements in both cover types in both years. Differences between...

  9. Influences of shelterwood prescriptions to aboveground carbon storage and herpetofaunal and small mammal communities

    Treesearch

    Padraic Conner; Yong Wang; Callie Jo Schweitzer

    2015-01-01

    We examined the response of herpetofaunal and small mammal communities to silvicultural treatments. In addition, differences between silvicultural treatments of carbon storage ratios in trees, shrubs, vines, herbaceous material, course woody debris, and fine woody debris were studied. A complete randomized design with multiple replications, 20 experimental stands of...

  10. 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.

  11. New and modified techniques for studying nitrogen-fixing bacteria in small mammal droppings.

    Treesearch

    C.Y. Li; Chris. Maser

    1986-01-01

    Nitrogen-fixing bacteria in small mammal droppings are potentially important to forest productivity. As we study this phenomenon, however, we continually find unknowns, such as bacteria that we cannot isolate and purify because we do not know which techniques to use. For example, we have recently observed acetylene reduction in the droppings of the tundra vole (

  12. The riparian ecosystem management study: response of small mammals to streamside buffers in western Washington

    Treesearch

    Martin G. Raphael; Randall J. Wilk

    2013-01-01

    One of the fundamental concepts behind the conservation strategy in the U.S. federal Northwest Forest Plan is the importance of habitat buff ers in providing functional stream and streamside ecosystems. To better understand the importance of riparian buff ers in providing habitat for associated organisms, we investigated responses of small mammals to various streamside...

  13. 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

  14. Prevalence of antibodies against Ehrlichia spp. and Orientia tsutsugamushi in small mammals around harbors in Taiwan.

    PubMed

    Tsai, Kun-Hsien; Chang, Shu-Feng; Yen, Tsai-Ying; Shih, Wei-Liang; Chen, Wan-Jen; Wang, Hsi-Chieh; Yu, Xue-Jie; Wen, Tzai-Hung; Wu, Wen-Jer; Shu, Pei-Yun

    2016-01-27

    Tick-borne ehrlichiosis and mite-borne scrub typhus represent important emerging zoonotic rickettsial diseases. Although scrub typhus has been recognized by the Taiwanese public health system, information on ehrlichial infections is scarce in Taiwan. In this study, the risk of spread of ectoparasites on rodents through aerial and marine transportation was assessed in international and domestic harbors. Here, we report the first systematic surveillance of seroprevalence against Ehrlichia spp. in small mammals on the main island of Taiwan. In total, 1648 small mammals were trapped from 8 international ports, 18 domestic fishing harbors, and 7 local public health centers around Taiwan from November 2004 to December 2008. Sera were analyzed using indirect immunofluorescence assays to detect IgG antibodies against Ehrlichia chaffeensis and Orientia tsutsugamushi. A serum titer of ≧1:80 was considered positive. Antibodies against Ehrlichia spp. and O. tsutsugamushi were detected in 3.28% and 4.92% of small mammals active around harbors, respectively. The seropositive rate against Ehrlichia was higher in northern Taiwan from 2005 to 2008. However, O. tsutsugamushi infections increased in southern Taiwan during this period. The serological evidence of ehrlichial and O. tsutsugamushi infections in all international ports were included in the study. No significant differences were found among the seropositive rates of Ehrlichia spp. and O. tsutsugamushi in small mammals trapped between international and local harbors. The overall prevalence of Ehrlichia spp. and O. tsutsugamushi infections in small mammals active around harbors was 3.28% and 4.92%, respectively. The results provided serological evidence supporting the potential risks of transporting pathogens through air and maritime traffic. This study highlights serious issues of the emergence and spread of rickettsial diseases in Taiwan. The incidence of human ehrlichiosis requires further investigation.

  15. 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

  16. Drivers of Echinococcus multilocularis Transmission in China: Small Mammal Diversity, Landscape or Climate?

    PubMed Central

    Giraudoux, Patrick; Raoul, Francis; Pleydell, David; Li, Tiaoying; Han, Xiuming; Qiu, Jiamin; Xie, Yan; Wang, Hu; Ito, Akira; Craig, Philip S.

    2013-01-01

    Background Human alveolar echinococcocosis (AE) is a highly pathogenic zoonotic disease caused by the larval stage of the cestode E. multilocularis. Its life-cycle includes more than 40 species of small mammal intermediate hosts. Therefore, host biodiversity losses could be expected to alter transmission. Climate may also have possible impacts on E. multilocularis egg survival. We examined the distribution of human AE across two spatial scales, (i) for continental China and (ii) over the eastern edge of the Tibetan plateau. We tested the hypotheses that human disease distribution can be explained by either the biodiversity of small mammal intermediate host species, or by environmental factors such as climate or landscape characteristics. Methodology/findings The distributions of 274 small mammal species were mapped to 967 point locations on a grid covering continental China. Land cover, elevation, monthly rainfall and temperature were mapped using remotely sensed imagery and compared to the distribution of human AE disease at continental scale and over the eastern Tibetan plateau. Infection status of 17,589 people screened by abdominal ultrasound in 2002–2008 in 94 villages of Tibetan areas of western Sichuan and Qinghai provinces was analyzed using generalized additive mixed models and related to epidemiological and environmental covariates. We found that human AE was not directly correlated with small mammal reservoir host species richness, but rather was spatially correlated with landscape features and climate which could confirm and predict human disease hotspots over a 200,000 km2 region. Conclusions/Significance E. multilocularis transmission and resultant human disease risk was better predicted from landscape features that could support increases of small mammal host species prone to population outbreaks, rather than host species richness. We anticipate that our study may be a starting point for further research wherein landscape management could be used

  17. Cutaneous wound healing in aging small mammals: a systematic review.

    PubMed

    Kim, Dong Joo; Mustoe, Thomas; Clark, Richard A F

    2015-01-01

    As the elderly population grows, so do the clinical and socioeconomic burdens of nonhealing cutaneous wounds, the majority of which are seen among persons over 60 years of age. Human studies on how aging effects wound healing will always be the gold standard, but studies have ethical and practical hurdles. Choosing an animal model is dictated by costs and animal lifespan that preclude large animal use. Here, we review the current literature on how aging effects cutaneous wound healing in small animal models and, when possible, compare healing across studies. Using a literature search of MEDLINE/PubMed databases, studies were limited to those that utilized full-thickness wounds and compared the wound-healing parameters of wound closure, reepithelialization, granulation tissue fill, and tensile strength between young and aged cohorts. Overall, wound closure, reepithelialization, and granulation tissue fill were delayed or decreased with aging across different strains of mice and rats. Aging in mice was associated with lower tensile strength early in the wound healing process, but greater tensile strength later in the wound healing process. Similarly, aging in rats was associated with lower tensile strength early in the wound healing process, but no significant tensile strength difference between young and old rats later in healing wounds. From studies in New Zealand White rabbits, we found that reepithelialization and granulation tissue fill were delayed or decreased overall with aging. While similarities and differences in key wound healing parameters were noted between different strains and species, the comparability across the studies was highly questionable, highlighted by wide variability in experimental design and reporting. In future studies, standardized experimental design and reporting would help to establish comparable study groups, and advance the overall knowledge base, facilitating the translatability of animal data to the human clinical condition.

  18. Effects of field exposure to diazinon on small mammals inhabiting a semienclosed prairie grassland ecosystem. I. Ecological and reproductive effects.

    PubMed

    Sheffield, S R; Lochmiller, R L

    2001-02-01

    The widespread use of cholinesterase-inhibiting pesticides in the environment presents increasing concerns about their effects on human, wildlife, and ecosystem health. As a group, these pesticides are generally highly toxic and have great potential for negatively affecting nontarget organisms. Small mammals have proven to be ideal biomonitors of environmental contaminants, and were used here to test for possible effects of a widely used cholinesterase-inhibiting insecticide, diazinon, in a natural field setting. Using 12 0.1-ha terrestrial mesocosms, we examined the effects of low-level diazinon exposure on the small mammal communities inhabiting semienclosed grassland ecosystems. Our primary objective was to test the hypothesis that diazinon, applied at two different recommended label application rates, would not cause any observable adverse ecological or reproductive effects on small mammal populations and communities. Experimental small mammal communities consisting of Sigmodon hispidus, Microtus ochrogaster, Reithrodontomys fulvescens, and Mus musculus were stocked at natural densities and sex ratios inside empty mesocosms. Diazinon 4E was applied at two different maximum recommended label application rates, 0.56 kg a.i./ha (1x) and 4.5 kg a.i./ha (8x), and controls remained unsprayed, with four enclosures (replicates) per treatment. Two 30-d trials were run during peak rodent breeding seasons and enclosures were sampled on days 2, 16, and 30 of each trial. Recovery of small mammals was not significantly different among treatments, although fewer animals were recovered from the diazinon-exposed enclosures in both trials. Analysis of trapping data suggested that the normally strong competitive relationship between Sigmodon and Microtus may be altered by the pesticide, favoring Microtus in the diazinon-exposed enclosures. Incidence of reproductive condition was found to be reduced 20 to 80% and 33 to 100% in diazinon-exposed males and females, respectively

  19. 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.

  20. 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.

  1. 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.

  2. Small-mammal abundance at three elevations on a mountain in central Vermont, USA: a sixteen-year record

    Treesearch

    Robert T. Brooks; Harvey R. Smith; William M. Healy

    1998-01-01

    As part of a study of forest resilience to gypsy moth (Lymantria dispar) defoliation, small mammals were sampled with live (box) and pitfall traps for 16 years at three elevations on a mountain in west-central Vermont, USA. The more mesic, lowerslope location had the most diverse small-mammal community. White-footed mice (Peromyscus leucopus) were the most commonly...

  3. 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.

  4. 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.

  5. Flea and Small Mammal Species Composition in Mixed-Grass Prairies: Implications for the Maintenance of Yersinia pestis.

    PubMed

    Maestas, Lauren P; Britten, Hugh B

    2017-07-01

    Maintenance of sylvatic plague in prairie dogs (Cynomis spp.) was once thought unlikely due to high mortality rates; yet more recent findings indicate that low-level enzootic plague may be maintained in susceptible prairie dog populations. Another hypothesis for the maintenance of sylvatic plague involves small mammals, other than prairie dogs, as an alternative reservoir in the sylvatic plague system. These hypotheses, however, are not mutually exclusive, as both prairie dogs and small mammals could together be driving sylvatic cycles of plague. The concept of a bridging vector has been used to explain the transmission of pathogens from one host species to another. In the case of sylvatic plague, this would require overlap in fleas between small mammals and prairie dogs, and potentially other species such as carnivores. Our goal was to evaluate the level of flea sharing between black-tailed prairie dogs (Cynomis ludovicianus) and other small mammals in a mixed-grass prairie in South Dakota. We investigated the species richness of small mammals and small-mammal fleas in a mixed-grass prairie system and compared findings with previous studies from a short-grass ecosystem in Colorado. Over the summer field seasons 2014-2016 we live-trapped small mammals, collected fleas, and showed differences between both the flea and small mammal composition of the two systems. We also recorded higher densities of deer mice and lower densities of northern grasshopper mice in mixed versus shortgrass prairies. We confirmed, as is the case in shortgrass prairies, a lack of substantial flea species overlap on small mammal hosts and fleas from prairie dogs and their burrows. Moreover this study demonstrates that although small mammals may not play a large part in interepizootic plague cycling in shortgrass prairie ecosystems, their role in mixed-grass prairies requires further evaluation.

  6. 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.

  7. Effect of landscape features on the relationship between Ixodes ricinus ticks and their small mammal hosts.

    PubMed

    Perez, Grégoire; Bastian, Suzanne; Agoulon, Albert; Bouju, Agnès; Durand, Axelle; Faille, Frédéric; Lebert, Isabelle; Rantier, Yann; Plantard, Olivier; Butet, Alain

    2016-01-15

    The consequences of land use changes are among the most cited causes of emerging infectious diseases because they can modify the ecology and transmission of pathogens. This is particularly true for vector-borne diseases which depend on abiotic (e.g. climate) and biotic conditions (i.e. hosts and vectors). In this study, we investigated how landscape features affect the abundances of small mammals and Ixodes ricinus ticks, and how they influence their relationship. From 2012 to 2014, small mammals and questing I. ricinus ticks were sampled in spring and autumn in 24 sites located in agricultural and forest landscapes in Brittany, France. We tested the effects of landscape features (composition and configuration) on the abundances of small mammal species and immature ticks and their relationship. Additionally, we quantified the larval tick burden of small mammals in 2012 to better describe this relationship. The nymph abundance was positively influenced by the larval occurrence and the wood mouse Apodemus sylvaticus abundance the previous spring because they hosted tenfold more larvae than the bank vole Myodes glareolus. The bank vole abundance in spring and autumn had a negative and positive effect, respectively, on the nymph abundance. In agricultural landscapes, wood mice were positively influenced by woodland cover and woodland/hedgerow-grassland ecotone, whereas bank voles showed the opposite or non-significant responses to these landscape variables. The woodland cover had a positive effect on immature ticks. The landscape configuration, likely by affecting the landscape connectivity, influences the small mammal communities in permanent habitats. Our study showed that the wood mouse, due to its dominance and to its tolerance to ticks, feeds a substantial proportion of larvae. The acquired resistance to ticks in the bank vole can reduce its role as a trophic resource over time. The nymph abundance seems indirectly influenced by landscape features via their

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

    PubMed

    Terry, Rebecca C; Rowe, Rebecca J

    2015-08-04

    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.

  9. 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

  10. 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.

  11. 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.

  12. [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.

  13. Movement trajectories and habitat partitioning of small mammals in logged and unlogged rain forests on Borneo.

    PubMed

    Wells, Konstans; Pfeiffer, Martin; Lakim, Maklarin B; Kalko, Elisabeth K V

    2006-09-01

    1. Non-volant animals in tropical rain forests differ in their ability to exploit the habitat above the forest floor and also in their response to habitat variability. It is predicted that specific movement trajectories are determined both by intrinsic factors such as ecological specialization, morphology and body size and by structural features of the surrounding habitat such as undergrowth and availability of supportive structures. 2. We applied spool-and-line tracking in order to describe movement trajectories and habitat segregation of eight species of small mammals from an assemblage of Muridae, Tupaiidae and Sciuridae in the rain forest of Borneo where we followed a total of 13,525 m path. We also analysed specific changes in the movement patterns of the small mammals in relation to habitat stratification between logged and unlogged forests. Variables related to climbing activity of the tracked species as well as the supportive structures of the vegetation and undergrowth density were measured along their tracks. 3. Movement patterns of the small mammals differed significantly between species. Most similarities were found in congeneric species that converged strongly in body size and morphology. All species were affected in their movement patterns by the altered forest structure in logged forests with most differences found in Leopoldamys sabanus. However, the large proportions of short step lengths found in all species for both forest types and similar path tortuosity suggest that the main movement strategies of the small mammals were not influenced by logging but comprised generally a response to the heterogeneous habitat as opposed to random movement strategies predicted for homogeneous environments. 4. Overall shifts in microhabitat use showed no coherent trend among species. Multivariate (principal component) analysis revealed contrasting trends for convergent species, in particular for Maxomys rajah and M. surifer as well as for Tupaia longipes and T

  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. © 2013 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley

  16. 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.

  17. 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.

  18. Predicting above-ground density and distribution of small mammal prey species at large spatial scales

    PubMed Central

    2017-01-01

    Grassland and shrub-steppe ecosystems are increasingly threatened by anthropogenic activities. Loss of native habitats may negatively impact important small mammal prey species. Little information, however, is available on the impact of habitat variability on density of small mammal prey species at broad spatial scales. We examined the relationship between small mammal density and remotely-sensed environmental covariates in shrub-steppe and grassland ecosystems in Wyoming, USA. We sampled four sciurid and leporid species groups using line transect methods, and used hierarchical distance-sampling to model density in response to variation in vegetation, climate, topographic, and anthropogenic variables, while accounting for variation in detection probability. We created spatial predictions of each species’ density and distribution. Sciurid and leporid species exhibited mixed responses to vegetation, such that changes to native habitat will likely affect prey species differently. Density of white-tailed prairie dogs (Cynomys leucurus), Wyoming ground squirrels (Urocitellus elegans), and leporids correlated negatively with proportion of shrub or sagebrush cover and positively with herbaceous cover or bare ground, whereas least chipmunks showed a positive correlation with shrub cover and a negative correlation with herbaceous cover. Spatial predictions from our models provide a landscape-scale metric of above-ground prey density, which will facilitate the development of conservation plans for these taxa and their predators at spatial scales relevant to management. PMID:28520757

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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. © 2011 The Authors. Medical and Veterinary Entomology © 2011 The Royal Entomological Society.

  4. 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.

  5. 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.

  6. Predicting above-ground density and distribution of small mammal prey species at large spatial scales.

    PubMed

    Olson, Lucretia E; Squires, John R; Oakleaf, Robert J; Wallace, Zachary P; Kennedy, Patricia L

    2017-01-01

    Grassland and shrub-steppe ecosystems are increasingly threatened by anthropogenic activities. Loss of native habitats may negatively impact important small mammal prey species. Little information, however, is available on the impact of habitat variability on density of small mammal prey species at broad spatial scales. We examined the relationship between small mammal density and remotely-sensed environmental covariates in shrub-steppe and grassland ecosystems in Wyoming, USA. We sampled four sciurid and leporid species groups using line transect methods, and used hierarchical distance-sampling to model density in response to variation in vegetation, climate, topographic, and anthropogenic variables, while accounting for variation in detection probability. We created spatial predictions of each species' density and distribution. Sciurid and leporid species exhibited mixed responses to vegetation, such that changes to native habitat will likely affect prey species differently. Density of white-tailed prairie dogs (Cynomys leucurus), Wyoming ground squirrels (Urocitellus elegans), and leporids correlated negatively with proportion of shrub or sagebrush cover and positively with herbaceous cover or bare ground, whereas least chipmunks showed a positive correlation with shrub cover and a negative correlation with herbaceous cover. Spatial predictions from our models provide a landscape-scale metric of above-ground prey density, which will facilitate the development of conservation plans for these taxa and their predators at spatial scales relevant to management.

  7. 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.

  8. 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.

  9. 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.

  10. Differences in the ability of vegetation models to predict small mammal abundance in different aged Douglas-fir forests

    Treesearch

    Cathy A. Taylor; C. John Ralph; Arlene T. Doyle

    1988-01-01

    Three trapping techniques for small mammals were used in 47 study stands in northern California and southern Oregon and resulted in different capture frequencies by the different techniques. In addition, the abundances of mammals derived from the different techniques produced vegetation association models which were often quite different. Only the California redbacked...

  11. 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

  12. 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

  13. 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

  14. 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. © 2015 Anatomical Society.

  15. 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.

  16. Effects of clearcutting with corridor retention on abundance, richness, and diversity of small mammals in the Coastal Plain of South Carolina, USA.

    Treesearch

    Nicole L. Constantine; Tyler A. Campbell; William M. Baughman; Timothy B. Harrington; Brian R. Chapman; Karl V. Miller

    2004-01-01

    We studied six pine plantations in coastal South Carolina to determine the influence of clearcutting with corridor retention on small mammal abundance, richness, and diversity. Small mammals were live-trapped in recently clearcut stands that retained pine corridors 100 m in width and in adjacent pine plantations, 20--23-years-old. We compared small mammal communities...

  17. Investigating the effects of forest structure on the small mammal community in frequent-fire coniferous forests using capture-recapture models for stratified populations

    Treesearch

    Rahel Sollmann; Angela M. White; Beth Gardner; Patricia N. Manley

    2015-01-01

    Small mammals comprise an important component of forest vertebrate communities. Our understanding of how small mammals use forested habitat has relied heavily on studies in forest systems not naturally prone to frequent disturbances. Small mammal populations that evolved in frequent-fire forests, however, may be less restricted to specific habitat conditions due to the...

  18. Ticks (Acari: Ixodidae) collected from small and medium-sized Kansas mammals.

    PubMed

    Brillhart, D B; Fox, L B; Upton, S J

    1994-05-01

    Seven species of hard-bodied ticks were collected from 20 species of small and medium-sized mammals in Kansas; Amblyomma americanum L., Dermacentor variabilis (Say), Haemaphysalis leporispalustris (Packard), Ixodes cookei Packard, I. kingi Bishopp, I. sculptus Neumann, and I. texanus Banks. Dermacentor variabilis was found statewide, A. americanum only in the eastern one-third of the state, and the Ixodes spp. and H. leporispalustris were widely scattered. The most common tick found was D. variabilis, both by itself and in association with other ticks. Mammals that ticks were collected from included Canis latrans Say, Cynomys ludovicianus ludovicianus (Ord), Didelphis virginianus Kerr, Geomys bursarius (Shaw), Lynx rufus (Schreber), Marmota monax bunkeri Black, Mephitis mephitis (Schreber), Microtus ochrogaster (Wagner), Mus musculus L., Peromyscus leucopus (Rafinesque), P. maniculatus (Wagner), Procyon lotor hirtus Nelson and Goldman, Reithrodontomys megalotis (Baird), Sciurus niger rufiventer Geoffroy, Sigmodon hispidus texianus (Audubon and Bachman), Sylvilagus floridanus (J. A. Allen), Taxidea taxus taxus (Schreber), and Vulpes velox velox (Say).

  19. [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

  20. 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

  1. 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.

  2. 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

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

    PubMed

    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.

  4. Could giant impacts cripple core dynamos of small terrestrial planets?

    NASA Astrophysics Data System (ADS)

    Arkani-Hamed, Jafar; Ghods, Abdolreza

    2011-04-01

    Large impacts not only create giant basins on terrestrial planets but also heat their interior by shock waves. We investigate the impacts that have created the largest basins existing on the planets: Utopia on Mars, Caloris on Mercury, Aitken on Moon, all formed at ˜4 Ga. We determine the impact-induced temperature increases in the interior of a planet using the "foundering" shock heating model of Watters et al. (Watters, W.A., Zuber, M.T., Hager, B.H. [2009]. J. Geophys. Res. 114, E02001. doi: 10.1029/2007JE002964). The post-impact thermal evolution of the planet is investigated using 2D axi-symmetric convection in a spherical shell of temperature-dependent viscosity and thermal conductivity, and pressure-dependent thermal expansion. The impact heating creates a superheated giant plume in the upper mantle which ascends rapidly and develops a strong convection in the mantle of the sub-impact hemisphere. The upwelling of the plume rapidly sweeps up the impact-heated base of the mantle away from the core-mantle boundary and replaces it with the colder surrounding material, thus reducing the effects of the impact-heated base of the mantle on the heat flux out of core. However, direct shock heating of the core stratifies the core, suppresses the pre-existing thermal convection, and cripples a pre-existing thermally-driven core dynamo. It takes about 17, 4, and 5 Myr for the stratified cores of Mars, Mercury, and Moon to exhaust impact heat and resume global convection, possibly regenerating core dynamos.

  5. A killer appetite: metabolic consequences of carnivory in marine mammals.

    PubMed

    Williams, T M; Haun, J; Davis, R W; Fuiman, L A; Kohin, S

    2001-07-01

    Among terrestrial mammals, the morphology of the gastrointestinal tract reflects the metabolic demands of the animal and individual requirements for processing, distributing, and absorbing nutrients. To determine if gastrointestinal tract morphology is similarly correlated with metabolic requirements in marine mammals, we examined the relationship between basal metabolic rate (BMR) and small intestinal length in pinnipeds and cetaceans. Oxygen consumption was measured for resting bottlenose dolphins and Weddell seals, and the results combined with data for four additional species of carnivorous marine mammal. Data for small intestinal length were obtained from previously published reports. Similar analyses were conducted for five species of carnivorous terrestrial mammal, for which BMR and intestinal length were known. The results indicate that the BMRs of Weddell seals and dolphins resting on the water surface are 1.6 and 2.3 times the predicted levels for similarly sized domestic terrestrial mammals, respectively. Small intestinal lengths for carnivorous marine mammals depend on body size and are comparatively longer than those of terrestrial carnivores. The relationship between basal metabolic rate (kcal day(-1)) and small intestinal length (m) for both marine and terrestrial carnivores was, BMR=142.5 intestinal length(1.20) (r(2)=0.83). We suggest that elevated metabolic rates among marine mammal carnivores are associated with comparatively large alimentary tracts that are presumably required for supporting the energetic demands of an aquatic lifestyle and for feeding on vertebrate and invertebrate prey.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. Leptospira Infection Prevalence in Small Mammal Host Populations on Three Hawaiian Islands

    PubMed Central

    Wong, Mayee; Katz, Alan R.; Li, Dongmei; Wilcox, Bruce A.

    2012-01-01

    We describe the geographic distribution and variation in host-pathogen specificity for Leptospira-infected small mammals collected concurrently from three Hawaiian Islands over a period of 14 years: 1990–2003. Four serogroups (Icterohaemorrhagiae, Ballum, Sejroe, and Australis) were identified from the 15,171 animals tested. Serogroup prevalence differed across host species and islands (P < 0.0001 for each), but not across years. The host associations and biogeographic patterns of Leptospira in Hawaii indicate a pathogen community shaped by ecological factors. PMID:22855767

  17. Nidicolous ticks of small mammals in Anaplasma phagocytophilum-enzootic sites in northern California

    PubMed Central

    Foley, Janet; Rejmanek, Daniel; Fleer, Katryna; Nieto, Nathan

    2011-01-01

    Ixodes spp. tick-borne zoonotic diseases are present across the Holarctic in humans, domestic animals, and wildlife. Small mammals are reservoirs for the rickettsial pathogen Anaplasma phagocytophilum and tick vectors may include catholic-feeding bridge vectors as well as host-specialist or nidicolous ticks. Far western North American communities in which A. phagocytophilum is maintained are complex ecologically, with multiple reservoir host and tick species, multiple strains of the bacterial pathogen A. phagocytophilum and differences in dynamics of hosts and vectors across heterogeneous landscapes. We evaluated sites in northern California in order to identify primarily nidicolous ticks and the hosts they infest. A total of 667 ticks was found in 11 study sites, including 288 on flags and 379 attached to small mammals. Larvae were over-represented among attached ticks and adults on flags. The most abundant species was I. pacificus. Two-hundred fourteen nidicolous ticks were found, most abundantly I. angustus and I. spinipalpis. All adult I. ochotonae, I. auritulus, I. angustus, I. jellisoni, and I. woodi were female, while the male:female ratio of I. spinipalpis was 1.2:1 and 1:1 for I. pacificus. The greatest number of ticks was obtained from Tamias ochrogenys, Peromyscus spp., and Neotoma fuscipes. Of 234 small mammal individuals that were infested with Ixodes spp., only 81 (34.6%) were infested with I. pacificus. The remaining infested small mammals hosted nidicolous tick species. Eight ticks were PCR-positive, including 6 I. pacificus (one adult, one larva, and 6 nymphs), and 2 adult I. ochotonae and high PCR prevalences of 18% and 9% were detected in woodrats and chipmunks, respectively. Nymphal I. angustus ticks were active year-long with a possible increase in August while larval activity was only observed in December and spring months and adults only during spring and fall. Overall, we show high tick species richness and year-round high levels of

  18. 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

  19. 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.

  20. [Faunistic analysis of the fleas on small mammals in the trans-Aral Sea area].

    PubMed

    Burdelov, L A; Zhurbanazarov, I Zh; Rudenchik, N F

    1988-01-01

    Materials on occurrence and abundance of 36 species of fleas on 17 species of small mammals are systematized. A great similarity between the faunas of ectoparasites of rodents and predators has been shown by means of special indices. The conception of parasitic field is formulated which implies the phenomenon of community of the fauna of plague vectors parasitic on its potential carriers. Some aspects of the formation of parasitic field and its possible effect the epizootic process are considered. It is established that the similarity between the faunas of fleas from different animals is ensured in this region first of all by a wide distribution of specific parasites of gerbils.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. Can remote infrared cameras be used to differentiate small, sympatric mammal species? A case study of the black-tailed dusky antechinus, Antechinus arktos and co-occurring small mammals in southeast Queensland, Australia

    PubMed Central

    Dennis, Todd E.; Baker, Andrew M.

    2017-01-01

    The black-tailed dusky antechinus (Antechinus arktos) is an endangered, small carnivorous marsupial endemic to Australia, which occurs at low population density along with abundant sympatric populations of other small mammals: Antechinus stuartii, Rattus fuscipes and Melomys cervinipes. Using A. arktos as a model species, we aimed to evaluate the effectiveness of infrared digital camera traps for detecting and differentiating small mammals and to comment on the broad applicability of this methodology. We also sought to understand how the detection probabilities of our target species varied over time and characterize their activity patterns. We installed 11 infrared cameras at one of only three known sites where A. arktos occurs for five consecutive deployments. Cameras were fixed to wooden stakes and oriented vertically, 35 cm above ground, directly facing bait containers. Using this method, we successfully recorded and identified individuals from all four species of small mammal known previously in the area from live trapping, including A. arktos. This validates the effectiveness of the infrared camera type and orientation for small mammal studies. Periods of activity for all species were highly coincident, showing a strong peak in activity during the same two-hour period immediately following sunset. A. arktos, A. stuartii and M. cervinipes also displayed a strong negative linear relationship between detection probability and days since deployment. This is an important finding for camera trapping generally, indicating that routine camera deployment lengths (of one-to-two weeks) between baiting events may be too long when targeting some small mammals. PMID:28792958

  7. Can remote infrared cameras be used to differentiate small, sympatric mammal species? A case study of the black-tailed dusky antechinus, Antechinus arktos and co-occurring small mammals in southeast Queensland, Australia.

    PubMed

    Gray, Emma L; Dennis, Todd E; Baker, Andrew M

    2017-01-01

    The black-tailed dusky antechinus (Antechinus arktos) is an endangered, small carnivorous marsupial endemic to Australia, which occurs at low population density along with abundant sympatric populations of other small mammals: Antechinus stuartii, Rattus fuscipes and Melomys cervinipes. Using A. arktos as a model species, we aimed to evaluate the effectiveness of infrared digital camera traps for detecting and differentiating small mammals and to comment on the broad applicability of this methodology. We also sought to understand how the detection probabilities of our target species varied over time and characterize their activity patterns. We installed 11 infrared cameras at one of only three known sites where A. arktos occurs for five consecutive deployments. Cameras were fixed to wooden stakes and oriented vertically, 35 cm above ground, directly facing bait containers. Using this method, we successfully recorded and identified individuals from all four species of small mammal known previously in the area from live trapping, including A. arktos. This validates the effectiveness of the infrared camera type and orientation for small mammal studies. Periods of activity for all species were highly coincident, showing a strong peak in activity during the same two-hour period immediately following sunset. A. arktos, A. stuartii and M. cervinipes also displayed a strong negative linear relationship between detection probability and days since deployment. This is an important finding for camera trapping generally, indicating that routine camera deployment lengths (of one-to-two weeks) between baiting events may be too long when targeting some small mammals.

  8. 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

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. Patterns of small mammal microhabitat utilization in cedar glade and deciduous forest habitats

    SciTech Connect

    Seagle, S.W.

    1985-01-01

    Differential microhabitat use by the small mammals inhabiting a cedar glade and a deciduous forest was investigated using discriminant function analysis of 30 structural parameters measured around the capture site of each animal. Ochrotomys nuttalli and Peromyscus leucopus utilize different microhabitats in the cedar glade, as do Blarina brevicauda and P. leucopus in the deciduous forest. P. leucopus was found to be a microhabitat generalist in the deciduous forest and a specialist in the cedar glade, whereas O. nuttalli and B. bravicauda were a microhabitat generalist and specialist, respectively. The sexes of P. leucopus were found to occupy different microhabitats in the deciduous forest but not in the cedar glade. Female P. leucopus occupied microhabitat with better protective cover in the deciduous forest. Comparisons of microhabitats used by the two species captured in each habitat with a random microhabitat sample and trap sites at which no animals were captured indicate that each habitat is a complex matrix of microhabitats, some of which are used by small mammals and some of which are not. 24 references, 5 figures, 5 tables.

  14. 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.

  15. The influence of trap density and sampling duration on the detection of small mammal species richness

    USGS Publications Warehouse

    Conard, J.M.; Baumgardt, J.A.; Gipson, P.S.; Althoff, D.P.

    2008-01-01

    Assessing species richness of small mammal communities is an important research objective for many live-trapping studies designed to assess or monitor biological diversity. We tested the effectiveness and efficiency of various trap densities for determining estimates and counts of small mammal species richness. Trapping was conducted in grassland habitats in northeastern Kansas during spring and fall of 2002 and 2003. Estimates and counts of species richness were higher at increased trap densities. This effect appeared to be primarily due to the higher number of individuals sampled at higher trap densities. At least 3 nights duration was needed to produce a stable estimate of species richness for the range of trap densities tested (9-144 trap stations/ha). Higher trap densities generally reached stable richness estimates in fewer nights than low density trapping arrangements. Given that counts and estimates of species richness were influenced by trap density and sampling duration, it is critical that these parameters are selected to most effectively meet research objectives.

  16. 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. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. 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.

  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. 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

  20. 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.

  1. 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. © 2016 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

  2. Radiation exposure and dose to small mammals in radon-rich soils.

    PubMed

    Macdonald, C R; Laverock, M J

    1998-07-01

    Protection of the environment from radionuclide releases requires knowledge of the normal background levels of radiation exposure in the exposed biotic community and an estimate of the detriment caused by additional exposure. This study modeled the background exposure and dose to the lungs of small burrowing mammals from 222Rn in artificial burrows in radon-rich soils at a site in southeastern Manitoba. E-PERM chambers used to measure 222Rn in soil showed good reproducibility of measurement, with an average coefficient of variance (CV) of about 10%. Geometric mean (GM) 222Rn concentrations at nine randomly selected sites ranged from 5,490 Bq/m3 (GSD = 1.57, n = 7) to 41,000 Bq/m3 (GSD = 1.02, n = 5). Long-term monitoring of 222Rn concentrations in artificial burrows showed large variation within and between burrows and did not show consistent variation with season, orientation of the burrow opening, or levels of 226Ra in the soil. Annual GM concentrations in individual burrows ranged from 7,480 Bq/m3 (GSD = 1.60) to 18,930 Bq/m3 (GSD = 1.81) in burrows several meters apart. A grand GM of 9,990 Bq/m3 (GSD = 1.81, n = 214) was measured over the site for the year. An exposure model was constructed for five small mammal species based on their respiration rates and the number of hours spent in the burrow, active or hibernating, exposed to soil gas 222Rn, and the time spent out of the burrow exposed to atmospheric 222Rn. A background dose of 0.9 mGy/a from atmospheric 222Rn (40 Bq/m3) was estimated for a large-bodied (80 kg), nonburrowing animal living on the soil surface. The highest exposures (mJ/a) in burrowing mammals occurred in those species with the highest respiration rates. Hibernation accounted for a small fraction of total annual exposure (<5%) because of very low respiration rates during this period. Absorbed dose to lung (mGy/a) was highest in the pocket gopher and decreased in the larger animals because of larger lung mass. Using mean 222Rn concentrations

  3. Intrinsic and extrinsic factors related to pathogen infection in wild small mammals in intensive milk cattle and swine production systems.

    PubMed

    Lovera, Rosario; Fernández, María Soledad; Jacob, Jens; Lucero, Nidia; Morici, Gabriel; Brihuega, Bibiana; Farace, María Isabel; Caracostantogolo, Jorge; Cavia, Regino

    2017-06-01

    Understanding the ecological processes that are involved in the transmission of zoonotic pathogens by small mammals may aid adequate and effective management measures. Few attempts have been made to analyze the ecological aspects that influence pathogen infection in small mammals in livestock production systems. We describe the infection of small mammals with Leptospira spp., Brucella spp., Trichinella spp. and Cysticercus fasciolaris and assess the related intrinsic and extrinsic factors in livestock production systems in central Argentina at the small mammal community, population and individual levels. Ten pig farms and eight dairy farms were studied by removal trapping of small mammals from 2008 to 2011. Each farm was sampled seasonally over the course of one year with cage and Sherman live traps. The 505 small mammals captured (14,359 trap-nights) included three introduced murine rodents, four native rodents and two opossums. Leptospira spp., anti-Brucella spp. antibodies and Trichinella spp. were found in the three murine rodents and both opossums. Rattus norvegicus was also infected with C. fasciolaris; Akodon azarae and Oligoryzomys flavescens with Leptospira spp.; anti-Brucella spp. antibodies were found in A. azarae. Two or more pathogens occurred simultaneously on 89% of the farms, and each pathogen was found on at least 50% of the farms. Pathogen infections increased with host abundance. Infection by Leptospira spp. also increased with precipitation and during warm seasons. The occurrence of anti-Brucella spp. antibodies was higher on dairy farms and during the winter and summer. The host abundances limit values, from which farms are expected to be free of the studied pathogens, are reported. Murine rodents maintain pathogens within farms, whereas other native species are likely dispersing pathogens among farms. Hence, we recommend preventing and controlling murines in farm dwellings and isolating farms from their surroundings to avoid contact with other

  4. Intrinsic and extrinsic factors related to pathogen infection in wild small mammals in intensive milk cattle and swine production systems

    PubMed Central

    Lovera, Rosario; Fernández, María Soledad; Jacob, Jens; Caracostantogolo, Jorge

    2017-01-01

    Background Understanding the ecological processes that are involved in the transmission of zoonotic pathogens by small mammals may aid adequate and effective management measures. Few attempts have been made to analyze the ecological aspects that influence pathogen infection in small mammals in livestock production systems. We describe the infection of small mammals with Leptospira spp., Brucella spp., Trichinella spp. and Cysticercus fasciolaris and assess the related intrinsic and extrinsic factors in livestock production systems in central Argentina at the small mammal community, population and individual levels. Methodology/Principal findings Ten pig farms and eight dairy farms were studied by removal trapping of small mammals from 2008 to 2011. Each farm was sampled seasonally over the course of one year with cage and Sherman live traps. The 505 small mammals captured (14,359 trap-nights) included three introduced murine rodents, four native rodents and two opossums. Leptospira spp., anti-Brucella spp. antibodies and Trichinella spp. were found in the three murine rodents and both opossums. Rattus norvegicus was also infected with C. fasciolaris; Akodon azarae and Oligoryzomys flavescens with Leptospira spp.; anti-Brucella spp. antibodies were found in A. azarae. Two or more pathogens occurred simultaneously on 89% of the farms, and each pathogen was found on at least 50% of the farms. Pathogen infections increased with host abundance. Infection by Leptospira spp. also increased with precipitation and during warm seasons. The occurrence of anti-Brucella spp. antibodies was higher on dairy farms and during the winter and summer. The host abundances limit values, from which farms are expected to be free of the studied pathogens, are reported. Conclusions/Significance Murine rodents maintain pathogens within farms, whereas other native species are likely dispersing pathogens among farms. Hence, we recommend preventing and controlling murines in farm dwellings and

  5. 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

  6. 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.

  7. 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.

  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. 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.

  10. Human Virus-Derived Small RNAs Can Confer Antiviral Immunity in Mammals.

    PubMed

    Qiu, Yang; Xu, Yanpeng; Zhang, Yao; Zhou, Hui; Deng, Yong-Qiang; Li, Xiao-Feng; Miao, Meng; Zhang, Qiang; Zhong, Bo; Hu, Yuanyang; Zhang, Fu-Chun; Wu, Ligang; Qin, Cheng-Feng; Zhou, Xi

    2017-06-20

    RNA interference (RNAi) functions as a potent antiviral immunity in plants and invertebrates; however, whether RNAi plays antiviral roles in mammals remains unclear. Here, using human enterovirus 71 (HEV71) as a model, we showed HEV71 3A protein as an authentic viral suppressor of RNAi during viral infection. When the 3A-mediated RNAi suppression was impaired, the mutant HEV71 readily triggered the production of abundant HEV71-derived small RNAs with canonical siRNA properties in cells and mice. These virus-derived siRNAs were produced from viral dsRNA replicative intermediates in a Dicer-dependent manner and loaded into AGO, and they were fully active in degrading cognate viral RNAs. Recombinant HEV71 deficient in 3A-mediated RNAi suppression was significantly restricted in human somatic cells and mice, whereas Dicer deficiency rescued HEV71 infection independently of type I interferon response. Thus, RNAi can function as an antiviral immunity, which is induced and suppressed by a human virus, in mammals. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. 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

  12. [Ecological niches of sucking lice (Phthiraptera: Anoplura) and their coevolution relationship with small mammal hosts in Yunnan, China].

    PubMed

    Meng, Yan-Fen; Guo, Xian-Guo; Men, Xing-Yuan; Wu, Dian

    2008-02-28

    To investigate the ecological niches of sucking lice (Phthiraptera: Anoplura) on the body surface of small mammal hosts and the co-evolutionary relationship between lice and mammal hosts in Yunnan Province. Thirty species of small mammals were captured and used as 30 resource sequences. The distribution and composition of the dominant 22 species of sucking lice on the body surface of the 30 species small mammal hosts were analyzed as the utilization proportion for each resource sequence. The niche breadth and proportional similarity were measured. SPSS 13.0 statistical software was used for analyzing the niche overlap matrix of sucking lice by hierarchical clustering analysis, and a dendrogram was made. The niche breadth was narrow for most species of sucking louse. Among the detected species, Hoplopleura pacifica showed the widest niche breadth, but only 0.1536. Indices of niche proportional similarity of most sucking lice were relatively small from 0.0005 to 0.4695. The 22 species of sucking lice were classified into 16 niche overlap groups, by lambda = 5.5, through a hierarchical clustering analysis for the niche overlaps, and the clustering process of most sucking lice was late. The sucking lice have a high specificity for hosts, of which different species show an apparent niche divergence on host selection. The results reveal a high coevolution between sucking lice and the mammal hosts.

  13. 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.

  14. 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.

  15. New flexible growth function and its application to the growth of small mammals.

    PubMed

    Wan, X; Zhong, W; Wang, M

    1998-01-01

    The function [formula: see text] where a is the upper asympotic weight and b, c, k are constants, is derived as a new flexible growth equation and evaluated using commonly applied growth functions such as Monomelecular, Gompertz, Logistic, Richards, France, Janoschek and Hill. Three sets of observations on growth of small mammal species (Microtus brandti and Ochotona curzoniae) are used to evaluate the fits of these functions. In addition, points of inflexion of these growth equations are also derived in this paper. The new function encompasses the Logistic and Monomolecular equation for different value of parameter b. It provides a flexible growth equation capable of describing smooth sigmoidal and diminishing returns behaviour. The success of the new equation in describing these sets of growth patterns underlines its credentials as a suitable additional growth function.

  16. 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

  17. 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, Bala; 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.

  18. 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.

  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. 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.

  1. 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

  2. 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

  3. 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.

  4. Atlantic small-mammal: a dataset of communities of rodents and marsupials of the Atlantic forests of South America.

    PubMed

    Bovendorp, Ricardo S; Villar, Nacho; de Abreu-Junior, Edson F; Bello, Carolina; Regolin, André L; Percequillo, Alexandre R; Galetti, Mauro

    2017-08-01

    The contribution of small mammal ecology to the understanding of macroecological patterns of biodiversity, population dynamics, and community assembly has been hindered by the absence of large datasets of small mammal communities from tropical regions. Here we compile the largest dataset of inventories of small mammal communities for the Neotropical region. The dataset reviews small mammal communities from the Atlantic forest of South America, one of the regions with the highest diversity of small mammals and a global biodiversity hotspot, though currently covering less than 12% of its original area due to anthropogenic pressures. The dataset comprises 136 references from 300 locations covering seven vegetation types of tropical and subtropical Atlantic forests of South America, and presents data on species composition, richness, and relative abundance (captures/trap-nights). One paper was published more than 70 yr ago, but 80% of them were published after 2000. The dataset comprises 53,518 individuals of 124 species of small mammals, including 30 species of marsupials and 94 species of rodents. Species richness averaged 8.2 species (1-21) per site. Only two species occurred in more than 50% of the sites (the common opossum, Didelphis aurita and black-footed pigmy rice rat Oligoryzomys nigripes). Mean species abundance varied 430-fold, from 4.3 to 0.01 individuals/trap-night. The dataset also revealed a hyper-dominance of 22 species that comprised 78.29% of all individuals captured, with only seven species representing 44% of all captures. The information contained on this dataset can be applied in the study of macroecological patterns of biodiversity, communities, and populations, but also to evaluate the ecological consequences of fragmentation and defaunation, and predict disease outbreaks, trophic interactions and community dynamics in this biodiversity hotspot. © 2017 by the Ecological Society of America.

  5. 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.

  6. 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.

  7. Candidatus Neoehrlichia mikurensis and Anaplasma phagocytophilum: prevalences and investigations on a new transmission path in small mammals and ixodid ticks.

    PubMed

    Obiegala, Anna; Pfeffer, Martin; Pfister, Kurt; Tiedemann, Tim; Thiel, Claudia; Balling, Anneliese; Karnath, Carolin; Woll, Dietlinde; Silaghi, Cornelia

    2014-12-04

    Small mammals are crucial for the life history of ixodid ticks, but their role and importance in the transmission cycle of tick-borne pathogens is mostly unknown. Candidatus Neoehrlichia mikurensis (CNM) and Anaplasma phagocytophilum are both tick-borne pathogens, and rodents are discussed to serve as main reservoir hosts for CNM but not for the latter especially in Germany. Analysing the prevalence of both pathogens in small mammals and their ticks in endemic regions may help to elucidate possible transmission paths in small mammal populations and between small mammals and ticks. In 2012 and 2013, small mammals were trapped at three different sites in Germany. DNA was extracted from different small mammal tissues, from rodent neonates, foetuses and from questing and attached ticks. DNA samples were tested for CNM and A. phagocytophilum by real-time PCR. Samples positive for A. phagocytophilum were further characterized at the 16S rRNA gene locus. CNM was detected in 28.6% of small mammals and in 2.2% of questing and 3.8% of attached ticks. Altogether 33 positive ticks were attached to 17 different hosts, while positive ticks per host ranged between one and seven. The prevalences for this pathogen differed significantly within small mammal populations comparing sites (χ(2): 13.3987; p: 0.0004) and between sexes. Male rodents had an approximately two times higher chance of infection than females (OR: 1.9652; 95% CI: 1.32-2.92). The prevalence for CNM was 31.8% (95% CI: 22-44) in rodent foetuses and neonates (23 of 67) from positive dams, and 60% (95% CI: 35.7-80.25) of positive gravid or recently parturient rodents (9 out of 15) had at least one positive foetus or neonate. Anaplasma phagocytophilum was detected at a low percentage in rodents (0-5.6%) and host-attached ticks (0.5-2.9%) with no significant differences between rodent species. However, attached nymphs were significantly more often infected than attached larvae (χ(2): 25.091; p: <0.0001). This study

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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

  14. Revisiting the cost of carnivory in mammals.

    PubMed

    Tucker, M A; Ord, T J; Rogers, T L

    2016-11-01

    Predator-prey relationships play a key role in the evolution and ecology of carnivores. An understanding of predator-prey relationships and how this differs across species and environments provides information on how carnivorous strategies have evolved and how they may change in response to environmental change. We aim to determine how mammals overcame the challenges of living within the marine environment; specifically, how this altered predator-prey body mass relationships relative to terrestrial mammals. Using predator and prey mass data collected from the literature, we applied phylogenetic piecewise regressions to investigate the relationship between predator and prey size across carnivorous mammals (51 terrestrial and 56 marine mammals). We demonstrate that carnivorous mammals have four broad dietary groups: small marine carnivores (< 11 000 kg) and small terrestrial carnivores (< 11 kg) feed on prey less than 5 kg and 2 kg, respectively. On average, large marine carnivores (> 11 000 kg) feed on prey equal to 0.01% of the carnivore's body size, compared to 45% or greater in large terrestrial carnivores (> 11 kg). We propose that differences in prey availability, and the relative ease of processing large prey in the terrestrial environment and small prey in marine environment, have led to the evolution of these novel foraging behaviours. Our results provide important insights into the selection pressures that may have been faced by early marine mammals and ultimately led to the evolution of a range of feeding strategies and predatory behaviours. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  15. 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.

  16. 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

  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. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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...

  3. 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...

  4. 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.

  5. 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…

  6. Response of small mammal populations to fuel treatment and precipitation in a ponderosa pine forest, New Mexico

    Treesearch

    Karen E. Bagne; Deborah M. Finch

    2009-01-01

    Mechanical and fire treatments are commonly used to reduce fuels where land use practices have encouraged accumulation of woody debris and high densities of trees. Treatments focus on restoration of vegetation structure, but will also affect wildlife populations. Small mammal populations were monitored before and after dense tree stands were thinned on 2,800 ha in NM,...

  7. Reptile, amphibian, and small mammal species associated with natural gas development in the Monongahela National Forest, West Virginia

    Treesearch

    Kurtis R. Moseley; W. Mark Ford; John W. Edwards; Mary B. Adams

    2010-01-01

    Burgeoning energy demand in the United States has led to increased natural gas exploration in the Appalachian Basin. Despite increasing natural gas development in the region, data about its impacts to wildlife are lacking. Our objective was to assess past and ongoing natural gas development impacts on reptiles, amphibians, and small mammals in the Monongahela National...

  8. Short-term responses of the small mammal communities to forest management within Missouri Ozark Forest Ecosystem Project sites

    Treesearch

    Debby K. Frantz; Rochelle B. Renken

    2002-01-01

    We conducted a capture-recapture study on the northeast-facing slopes of the MOFEP sites in south central Missouri to determine the initial effects of even- and uneven-aged forest management on species composition, species richness, and relative abundance of the small mammal communities. We compared changes between pre-treatment (1994-1995) and post-treatment (1998-...

  9. Right Place, Wrong Species: A 20-Year Review of Rabies Virus Cross Species Transmission among Terrestrial Mammals in the United States

    PubMed Central

    Wallace, Ryan M.; Gilbert, Amy; Slate, Dennis; Chipman, Richard; Singh, Amber; Cassie Wedd; Blanton, Jesse D.

    2014-01-01

    Introduction In the continental US, four terrestrial mammalian species are reservoirs for seven antigenic rabies virus variants. Cross species transmission (CST) occurs when a rabies virus variant causes disease in non-reservoir species. Methods This study analyzed national surveillance data for rabies in terrestrial mammals. The CST rate was defined as: number of rabid non-reservoir animals/number of rabid reservoir animals. CST rates were analyzed for trend. Clusters of high CST rate counties were evaluated using space-time scanning statistics. Results The number of counties reporting a raccoon variant CST rate >1.0 increased from 75 in 1992 to 187 in 2011; counties with skunk variant CST rates >1.0 remained unchanged during the same period. As of 2011, for every rabid raccoon reported within the raccoon variant region, there were 0.73 cases of this variant reported in non-reservoir animals. Skunks were the most common non-reservoir animal reported with the raccoon rabies variant. Domestic animals were the most common non-reservoir animal diagnosed with a skunk rabies virus variant (n = 1,601). Cross species transmission rates increased fastest among domestic animals. Conclusions Cross species transmission of rabies virus variants into non-reservoir animals increases the risk of human exposures and threatens current advances toward rabies control. Cross species transmission in raccoon rabies enzootic regions increased dramatically during the study period. Pet owners should vaccinate their dogs and cats to ensure against CST, particularly in regions with active foci of rabies circulation. Clusters of high CST activity represent areas for further study to better understand interspecies disease transmission dynamics. Each CST event has the potential to result in a rabies virus adapted for sustained transmission in a new species; therefore further understanding of the dynamics of CST may help in early detection or prevention of the emergence of new terrestrial

  10. 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

  11. Attitude and orbit control of small satellites for autonomous terrestrial target tracking

    NASA Astrophysics Data System (ADS)

    Ibrahim, Najmus S.

    Terrestrial target tracking using low Earth orbit satellites provides essential daily services and vital scientific data. In this thesis, the Attitude and Orbit Control System of such a terrestrial tracking satellite, Nanosatellite for Earth Monitoring and Observation Aerosol Monitor, is presented in detail. The satellite is a new generation Earth observation mission with the objective of detecting global atmospheric aerosol content through sub-degree pointing. The design is presented from initial hardware selection and budget development to operation definition and mission operation. The efficacy of performing precise autonomous Earth-pointing on a small satellite platform is validated through high fidelity simulations involving satellite and environmental dynamics, test-characterized hardware models and flight software-in-the-loop. The results provide practical target tracking methodologies which in the past have been publicly inaccessible to the author's best knowledge and which can be now be applied to a broad range of precise Earth-pointing satellites.

  12. 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.

  13. 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.

  14. A GPS logger and software for analysis of homing in pigeons and small mammals.

    PubMed

    Steiner, I; Bürgi, C; Werffeli, S; Dell'Omo, G; Valenti, P; Tröster, G; Wolfer, D P; Lipp, H P

    2000-12-01

    A detailed analysis of homing in pigeons and small mammals has remained difficult because the paths of the animals could not be reconstructed precisely. Here, we describe a lightweight global position system (GPS) data logger (35 g including battery and casing; 40 x 68 x 18 mm) that records the flight of pigeons and the path of dogs with an accuracy of +/-12 m. With one battery, the logger runs in continuous mode (1 fix/s) for 3.5 h and in power-saving mode (1 fix/5 s) for about 16 h, and stores a maximum of 100,000 data points that are downloaded to a PC. A module of our public domain software WINTRACK permits a detailed numerical and graphical analysis of path geometry, phases of resting and moving, and path similarity. The device can be adapted to different species provided that satellite signals can be received reliably and that the loggers can be recovered. We expect it to be useful for testing hypotheses about pigeon homing, assessing natural spatial behavior and orientation of many species, and anticipate further miniaturization.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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).

  1. 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

  2. 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.

  3. 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

  4. Distribution of fleas (Siphonaptera) among small mammals: mean abundance predicts prevalence via simple epidemiological model.

    PubMed

    Krasnov, Boris R; Stanko, Michal; Miklisova, Dana; Morand, Serge

    2005-09-01

    We used data on the abundance and distribution of fleas parasitic on small mammals in Slovakia and aimed: (i) to confirm a positive relationship between abundance and distribution fleas within and across host species; and (ii) to test if prevalence of fleas can be reliably predicted from a simple epidemiological model that takes into account flea mean abundance and its variance. Prevalence of a flea species increased with an increase in its mean abundance both within and across host species. We calculated prevalences both for each flea-host association and for each flea species across all hosts. Observed prevalences did not differ significantly from those predicted by the epidemiological model using parameters of Taylor's power relationship between mean abundance of fleas and its variance. Regressions of predicted prevalences against observed prevalences produced slope values that did not differ significantly from unity and were independent of scale (within or across host species). Our results demonstrated that up to 96% of variance in flea prevalence can be explained solely by their mean abundance. We concluded that, in general, there is no need to invoke other, more complex factors for the explanation of the variation in flea prevalence.

  5. 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.

  6. "Small" data in a big data world: archiving terrestrial ecology data at ORNL DAAC

    NASA Astrophysics Data System (ADS)

    Santhana Vannan, S. K.; Beaty, T.; Boyer, A.; Deb, D.; Hook, L.; Shrestha, R.; Thornton, M.; Virdi, M.; Wei, Y.; Wright, D.

    2016-12-01

    The Oak Ridge National Laboratory Distributed Active Archive Center (ORNL DAAC http://daac.ornl.gov), a NASA-funded data center, archives a diverse collection of terrestrial biogeochemistry and ecological dynamics observations and models in support of NASA's Earth Science program. The ORNL DAAC has been addressing the increasing challenge of publishing diverse small data products into an online archive while dealing with the enhanced need for integration and availability of these data to address big science questions. This paper will show examples of "small" diverse data holdings - ranging from the Daymet model output data to site-based soil moisture observation data. We define "small" by the data volume of these data products compared to petabyte scale observations. We will highlight the use of tools and services for visualizing diverse data holdings and subsetting services such as the MODIS land products subsets tool (at ORNL DAAC) that provides big MODIS data in small chunks. Digital Object Identifiers (DOI) and data citations have enhanced the availability of data. The challenge faced by data publishers now is to deal with the increased number of publishable data products and most importantly the difficulties of publishing small diverse data products into an online archive. This paper will also present our experiences designing a data curation system for these types of data. The characteristics of these data will be examined and their scientific value will be demonstrated via data citation metrics. We will present case studies of leveraging specialized tools and services that have enabled small data sets to realize their "big" scientific potential. Overall, we will provide a holistic view of the challenges and potential of small diverse terrestrial ecology data sets from data curation to distribution.

  7. Cold adaptive thermogenesis in small mammals from different geographical zones of China.

    PubMed

    Li, Q; Sun, R; Huang, C; Wang, Z; Liu, X; Hou, J; Liu, J; Cai, L; Li, N; Zhang, S; Wang, Y

    2001-07-01

    The mechanisms of thermogenesis and thermoregulation were studied in the tree shrew (Tupaia belangeri) and greater vole (Eothenomys miletus) of the subtropical region, and Brandt's vole (Microtus brandti), Mongolian gerbil (Meriones unguiculatus), Daurian ground squirrel (Spermophilus dauricus) and plateau pika (Ochotona curzoniae) of the northern temperate zone. Resting metabolic rate (RMR) and non-shivering thermogenesis (NST) increased significantly in T. belangeri, E. miletus, M. brandti and M. unguiculatus after cold acclimation (4 degrees C) for 4 weeks. In T. belangeri, the increase in RMR and thermogenesis at liver cellular level were responsible for enhancing the capacity of enduring cold stress, and homeothermia was simultaneously extended. Stable body temperature in M. brandti, E. miletus, M. unguiculatus and O. curzoniae was maintained mainly through increase in NST, brown adipose tissue (BAT) mass and its mitochondrial protein content, and the upregulation of uncoupling protein (UCP1) mRNA, as well as enhancement of the activity of cytochrome C oxidase, alpha-glycerophosphate oxidase and T(4) 5'-deiodinase in BAT mitochondria. The RMR in O. curzoniae and euthermic S. dauricus was not changed, while NST significantly increased during cold exposure; the former maintained their stable body temperature and mass, while body temperature in the latter declined by 4.8 degrees C. The serum T(3) concentration or ratio of T(3)/T(4) in all the species was enhanced after cold acclimation. Results indicated that: (1) the adaptive mechanisms of T. belangeri residing in the subtropical region to cold are primarily by increasing RMR and secondly by increasing NST, and the mechanisms of thermogenesis are similar to those in tropical mammals; (2) in small mammals residing in northern regions, the adaptation to cold is chiefly to increase NST; (3) the mechanism of cold-induced thermogenesis in E. miletus residing in subtropical and high mountain regions is similar to that

  8. 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

  9. 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

  10. 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.

  11. 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

  12. 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

  13. 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.

  14. 75 FR 13498 - Small Takes of Marine Mammals Incidental to Specified Activities; Dumbarton Bridge Seismic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-22

    ... Specified Activities; Dumbarton Bridge Seismic Retrofit Project, California AGENCY: National Marine... Dumbarton Bridge Seismic Retrofit Project. DATES: Effective August 15, 2010, through August 14, 2011..., NMFS received a request from Caltrans to harass marine mammals incidental to the Dumbarton Bridge...

  15. 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

  16. Tick-Borne Encephalitis Virus Diversity in Ixodid Ticks and Small Mammals in South-Western Siberia, Russia.

    PubMed

    Bakhvalova, Valentina N; Chicherina, Galina S; Potapova, Olga F; Panov, Victor V; Glupov, Victor V; Potapov, Mikhail A; Seligman, Stephen J; Morozova, Olga V

    2016-08-01

    The persistence of tick-borne encephalitis virus (TBEV) in nature is maintained by numerous species of reservoir hosts, multiple transmissions between vertebrates and invertebrates, and the virus adaptation to its hosts. Our Aim: was to compare TBEV isolates from ticks and small wild mammals to estimate their roles in the circulation of the viral subtypes. TBEV isolates from two species of ixodid ticks, four species of rodents, and one species of shrews in the Novosibirsk region, South-Western Siberia, Russia, were analyzed using bioassay, hemagglutination, hemagglutination inhibition, neutralization tests, ELISA, reverse transcription with real-time PCR, and phylogenetic analysis. TBEV RNA and/or protein E were found in 70.9% ± 3.0% of mammals and in 3.8% ± 0.4% of ticks. The TBEV infection rate, main subtypes, and neurovirulence were similar between ixodid tick species. However, the proportions of the virus that were pathogenic for laboratory mice and of the Far-Eastern (FE) subtype, as well as the viral loads with the Siberian and the European subtypes for the TBEV in Ixodes pavlovskyi Pomerantsev, 1946 were higher than in Ixodes persulcatus (P. Schulze, 1930). Percentages of infected Myodes rutilus, Sicista betulina, and Sorex araneus exceeded those of Apodemus agrarius and Myodes rufocanus. Larvae and nymphs of ticks were found mainly on rodents, especially on Myodes rufocanus and S. betulina. The proportion of TBEV-mixed infections with different subtypes in the infected ticks (55.9% ± 6.5%) was higher than in small mammals (36.1% ± 4.0%) (p < 0.01). Molecular typing revealed mono- or mixed infection with three main subtypes of TBEV in ticks and small mammals. The Siberian subtype was more common in ixodid ticks, and the FE subtype was more common in small mammals (p < 0.001). TBEV isolates of the European subtype were rare. TBEV infection among different species of small mammals did not correlate with their infestation rate with

  17. 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

  18. 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.

  19. Processes driving short-term temporal dynamics of small mammal distribution in human-disturbed environments.

    PubMed

    Martineau, Julie; Pothier, David; Fortin, Daniel

    2016-07-01

    As the impact of anthropogenic activities intensifies worldwide, an increasing proportion of landscape is converted to early successional stages every year. To understand and anticipate the global effects of the human footprint on wildlife, assessing short-term changes in animal populations in response to disturbance events is becoming increasingly important. We used isodar habitat selection theory to reveal the consequences of timber harvesting on the ecological processes that control the distribution dynamics of a small mammal, the red-backed vole (Myodes gapperi). The abundance of voles was estimated in pairs of cut and uncut forest stands, prior to logging and up to 2 years afterwards. A week after logging, voles did not display any preference between cut and uncut stands, and a non-significant isodar indicated that their distribution was not driven by density-dependent habitat selection. One month after harvesting, however, juvenile abundance increased in cut stands, whereas the highest proportions of reproductive females were observed in uncut stands. This distribution pattern appears to result from interference competition, with juveniles moving into cuts where there was weaker competition with adults. In fact, the emergence of source-sink dynamics between uncut and cut stands, driven by interference competition, could explain why the abundance of red-backed voles became lower in cut (the sink) than uncut (the source) stands 1-2 years after logging. Our study demonstrates that the influences of density-dependent habitat selection and interference competition in shaping animal distribution can vary frequently, and for several months, following anthropogenic disturbance.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. Foraging in space and time structure an African small mammal community.

    PubMed

    Abu Baker, Mohammad A; Brown, Joel S

    2014-06-01

    We used live-trapping and foraging to test for the effect of habitat selection and diet on structuring a community of six small mammals and one bird within the Soutpansberg, South Africa. We established grids that straddled adjacent habitats: woodland, rocky hillside, and grassland. Trapping and foraging were used to estimate abundance, habitat use, and species-specific foraging costs. The species with the highest abundance and foraging activity in a habitat, activity time, or food was considered the most efficient and presumed to have a competitive advantage. All species exhibited distinct patterns of spatial and temporal habitat preference which provided the main mechanism of coexistence, followed by diet selection. The study species were organized into three assemblages (α diversity): grassland, Rhabdomys pumilio, Dendromus melanotis, and Mus minutoides.; woodland, Aethomys ineptus and Micaelamys namaquensis; and rock-dwelling, M. namaquensis and Elephantulus myurus. Francolinus natalensis foraged in open rocky areas and under wooded islands within the grassland. Species organization across the habitats suggested that feeding opportunities are available within all habitats; however, distinct habitat preferences resulted from differing foraging aptitudes and efficiencies of the competing species. At Lajuma, species distribution and coexistence are promoted through distinct habitat preferences that were shaped by competition and species-specific foraging costs. The combination of trapping and foraging provided a mechanistic approach that integrates behavior into community ecology by 'asking' the animal to reveal its perspective of the environment. Using spatial and temporal foraging decisions-as behavioral indicators-enables us to guide our understanding for across-taxa species coexistence.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. Lack of a distinct gradient in biomarker responses in small mammals collected at different distances from a highway.

    PubMed

    Hamers, T; Smit, L A M; Bosveld, A T C; van den Berg, J H J; Koeman, J H; van Schooten, F J; Murk, A J

    2002-10-01

    This study describes biomarker effects in small mammals exposed to traffic emissions. Animals were collected at 10-50 m (site 1), 150-200 m (site 2), and 5 km (site 3) from a very busy highway (A2). To distinguish between routes of exposure, strictly carnivorous common shrews ( Sorex araneus) and predominantly herbivorous bank voles ( Clethrionomys glareolus) were collected. As a measure of exposure to polycyclic aromatic hydrocarbons (PAHs), aromatic DNA adduct levels were determined by (32)P-postlabeling techniques in tissue from heart, lung, and liver. Lead (Pb), cadmium (Cd), and copper (Cu) levels were analyzed in kidney as a measure of exposure to heavy metals. EROD and PROD activity and retinoid levels were determined in liver as effect biomarkers for exposure to PAHs and polyhalogenated aromatic hydrocarbons (PHAHs). Relatively high Cd levels in S. araneus and in particular elevated DNA adduct levels in C. glareolus indicated that small mammals at site 3 were exposed to more compounds than at sites 1 and 2 (3 > or = 1 > 2). The latter effect is probably due to an incidental and actual input of airborne pollutants that is deposited on plant surfaces. By consumption of above-ground vegetation, voles are chronically exposed to this pollution. Relatively high background input of PAHs probably hinders that the traffic-related gradient of airborne PAH concentrations found in an earlier study is reflected in DNA adduct levels in small mammals in the present study. Moreover, historical biomarkers for exposure to traffic emissions, such as increased kidney Pb levels, increased hepatic EROD activity, and disturbed hepatic vitamin A homeostasis are no longer applicable to indicate differences in exposure. This is a result of the ban on addition of Pb and chlorinated scavengers to gasoline and of cleaner combustion techniques, which were enforced by law over the past decade. Finally, it is advisable to use only juvenile small mammals for in situ monitoring of diffuse

  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. 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...

  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. [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.

  15. Ecological surveillance of small mammals at Dagmar North Training Area, Gyeonggi Province, Republic of Korea, 2001-2005.

    PubMed

    Kim, Heung Chul; Klein, Terry A; Kang, Hae Ji; Gu, Se Hun; Moon, Sung Sil; Baek, Luck Ju; Chong, Sung Tae; O'Guinn, Monica L; Lee, John S; Turell, Michael J; Song, Jin-Won

    2011-06-01

    A seasonal rodent-borne disease surveillance program was established at Dagmar North Training Area located near the demilitarized zone, Republic of Korea, from 2001 through 2005. Selected habitats surveyed included earthen banks separating rice paddies, fighting positions along a 5 m rock-faced earthen berm, and extensive tall grasses with various degrees of herbaceous and scrub vegetation associated with dirt roads, rice paddies, ditches, ponds, or the Imjin River. Of the nine species of small mammals captured, the striped field mouse (Apodemus agrarius), the primary reservoir for Hantaan virus, was the most frequently collected, representing 92.5% of the 1,848 small mammals captured. Males were captured similarly to females during the spring and summer seasons but were captured less frequently during the fall and winter seasons. Gravid rates were highest in the fall (25.5-57.3%) with the lowest rates during the summer (0.0-2.2%). Capture rates were the lowest along earthen banks separating rice paddies (5.5%) and highest in unmanaged tall grasses and crawling vegetation (15.3-43.5%). An increased knowledge of ecological factors that impact the abundance and distribution of small mammals and the associated ectoparasites and pathogens they harbor is critical for developing accurate disease risk assessments and mitigation strategies for preventing vector- and rodent-borne diseases among soldiers training in field environments. © 2011 The Society for Vector Ecology.

  16. Deformations of a small mud volcano revealed by multi-temporal terrestrial laser scanning

    NASA Astrophysics Data System (ADS)

    Hayakawa, Yuichi S.; Kusumoto, Shigekazu; Matta, Nobuhisa

    2017-04-01

    Activities of mud volcanoes are often regarded as signals of tectonics both in subaerial and submarine environments. Characteristics of mud volcanoes, including the composition of mud, water and gas, the underground structure, and the surface morphology, have often been investigated to reveal their activities. Here we explore the spatial variation in the deformation of a small terrestrial mud volcano, which has hardly been revealed without the use of high-resolution topographic measurements. The Murono mud volcano (north-central Japan) exhibits displacements of its ground surface morphology both by the earthquake events and in the inter-seismic quiescent periods. Multiple-time terrestrial laser scanning (TLS) was applied to detect the spatial variations in the ground surface deformations. After registering the point cloud data at different times using numerous points on unchanged reference features, deformations of the central zone of the mud volcano were detected at the scale of centimeters to decimeters, including both central uplift and peripheral subsidence with an elliptic spatial pattern. Open cracks on the central uplift area were also mapped, whose formation was successfully modeled with the displacement and stress fields estimated by the strong earthquakes. More gradual changes in the surface elevation of the mud volcano during the inter-seismic quiescent periods were also detected by the TLS data, and it was revealed that the spatial location of the center of uplift could have changed after an earthquake event.

  17. 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

  18. 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.

  19. 76 FR 56735 - Small Takes of Marine Mammals Incidental to Specified Activities; Cape Wind's High Resolution...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-14

    ... shift (TTS) and permanent threshold shift (PTS). There are no empirical data for onset of PTS in any marine mammal; therefore, PTS-onset must be estimated from TTS-onset measurements and from the rate of TTS growth with increasing exposure levels above the level eliciting TTS-onset. PTS is presumed to be...

  20. 75 FR 42691 - Small Takes of Marine Mammals Incidental to Specified Activities; Exploratorium Relocation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-22

    ... Exploratorium would use a steam or diesel-powered hammer delivering between 80,000 and 110,000 ft-lbs per blow..., respectively. Sound attenuation devices (e.g., wood block, bubble curtain) would be used during any impact... removal, and use of barges do not release loud sounds into the environment, marine mammal harassment...

  1. 78 FR 19217 - Small Takes of Marine Mammals Incidental to Specified Activities; Cape Wind's High Resolution...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ... of accomplishing the necessary monitoring and reporting that will result in increased knowledge of... increase knowledge of marine mammal species in Nantucket Sound. At least one NMFS-approved protected... discovery. CWA will provide photographs or video footage (if available) or other documentation of the...

  2. Short-term response of small mammals following oak regeneration silviculture treatments.

    Treesearch

    Amy L. Raybuck; Christopher E. Moorman; Christopher S. DePerno; Kevin Gross; Dean M. Simon; Gordon S. Warburton

    2012-01-01

    Upland, mixed-oak forests in the eastern United States have experienced widespread oak regeneration failure, largely due to cessation of anthropogenic disturbance. Silvicultural practices used to promote advance oak regeneration may affect ground-dwelling mammals. From May to August 2008 (pre-treatment), 2010 (first year post-treatment), and 2011 (second year post-...

  3. 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.

  4. Assessing Monkeypox Virus Prevalence in Small Mammals at the Human-Animal Interface in the Democratic Republic of the Congo.

    PubMed

    Doty, Jeffrey B; Malekani, Jean M; Kalemba, Lem's N; Stanley, William T; Monroe, Benjamin P; Nakazawa, Yoshinori U; Mauldin, Matthew R; Bakambana, Trésor L; Liyandja Dja Liyandja, Tobit; Braden, Zachary H; Wallace, Ryan M; Malekani, Divin V; McCollum, Andrea M; Gallardo-Romero, Nadia; Kondas, Ashley; Peterson, A Townsend; Osorio, Jorge E; Rocke, Tonie E; Karem, Kevin L; Emerson, Ginny L; Carroll, Darin S

    2017-10-03

    During 2012, 2013 and 2015, we collected small mammals within 25 km of the town of Boende in Tshuapa Province, the Democratic Republic of the Congo. The prevalence of monkeypox virus (MPXV) in this area is unknown; however, cases of human infection were previously confirmed near these collection sites. Samples were collected from 353 mammals (rodents, shrews, pangolins, elephant shrews, a potamogale, and a hyrax). Some rodents and shrews were captured from houses where human monkeypox cases have recently been identified, but most were trapped in forests and agricultural areas near villages. Real-time PCR and ELISA were used to assess evidence of MPXV infection and other Orthopoxvirus (OPXV) infections in these small mammals. Seven (2.0%) of these animal samples were found to be anti-orthopoxvirus immunoglobulin G (IgG) antibody positive (six rodents: two Funisciurus spp.; one Graphiurus lorraineus; one Cricetomys emini; one Heliosciurus sp.; one Oenomys hypoxanthus, and one elephant shrew Petrodromus tetradactylus); no individuals were found positive in PCR-based assays. These results suggest that a variety of animals can be infected with OPXVs, and that epidemiology studies and educational campaigns should focus on animals that people are regularly contacting, including larger rodents used as protein sources.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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 o