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.

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...

The Celtic fringe of Britain: insights from small mammal phylogeography

PubMed Central

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

2009-01-01

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. PMID:19793757

Production efficiency in small mammal populations.

PubMed

Grodziński, Władysław; French, Norman R

1983-01-01

Data from 102 populations of small mammals from 9 ecosystem types in Europe and in North and Central America were analyzed to define the relationship between productivity and respiration in insectivore and rodent populations. Productivity includes addition of new tissue in the form of growth of individual members of the population and new individuals added by reproduction. All data were recalculated to kilojoules per hectare per year. Linear regression was performed on logarithmic transformation of the data to determine the allometric form of the equation relating production to respiration. The relationship for rodents was determined to be: P=0.026 R 1.008 The relationship for shrews was significantly different both in slope and intercept from that for rodents, and was determined to be: P=0.543 R 0.628 The data were also divided according to functional group or trophic level, in addition to taxonomic grouping. Significant differences were found between herbivores and granivores but not among taxonomic divisions other than the Insectivora. Thus, ecological energetics of small mammals is correlated with trophic position but not with taxonomic position.These equations can be used for prediction of production in rodent and shrew populations where the biomass or respiration is known, thereby aiding the evaluation of trophic relationships in terrestrial communities.Production efficiency is lowest for insectivores (0.7%), and is higher for granivores (2.3%), omnivores (2.6%), and for herbivores (3.4%). The three parameters of respiration, production and assimilation define the conditions for existence of individual mammal populations. Population growth characteristics and species strategies are correlated with energetics and moderated through diet selection by the environment.

Dry paths effectively reduce road mortality of small and medium-sized terrestrial vertebrates.

PubMed

Niemi, Milla; Jääskeläinen, Niina C; Nummi, Petri; Mäkelä, Tiina; Norrdahl, Kai

2014-11-01

Wildlife passages are widely used mitigation measures designed to reduce the adverse impacts of roads on animals. We investigated whether road kills of small and medium-sized terrestrial vertebrates can be reduced by constructing dry paths adjacent to streams that pass under road bridges. The study was carried out in southern Finland during the summer of 2008. We selected ten road bridges with dry paths and ten bridges without them, and an individual dry land reference site for each study bridge on the basis of landscape and traffic features. A total of 307 dead terrestrial vertebrates were identified during the ten-week study period. The presence of dry paths decreased the amount of road-killed terrestrial vertebrates (Poisson GLMM; p < 0.001). That was true also when considering amphibians alone (p < 0.001). The evidence on road-kills on mammals was not such clear. In the mammal model, a lack of dry paths increased the amount of carcasses (p = 0.001) whereas the number of casualties at dry path bridges was comparable with dry land reference sites. A direct comparison of the dead ratios suggests an average efficiency of 79% for the dry paths. When considering amphibians and mammals alone, the computed effectiveness was 88 and 70%, respectively. Our results demonstrate that dry paths under road bridges can effectively reduce road-kills of small and medium-sized terrestrial vertebrates, even without guiding fences. Dry paths seemed to especially benefit amphibians which are a threatened species group worldwide and known to suffer high traffic mortality. Copyright © 2014 Elsevier Ltd. All rights reserved.

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.

Quantification of habitat fragmentation reveals extinction risk in terrestrial mammals

PubMed Central

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

2017-01-01

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. PMID:28673992

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

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.

Diversity of terrestrial mammal seed dispersers along a lowland Amazon forest regrowth gradient

PubMed Central

Arévalo-Sandi, Alexander; Bobrowiec, Paulo Estefano D.; Rodriguez Chuma, Victor Juan Ulises

2018-01-01

There is increasing interest in the restoration/regeneration of degraded tropical habitats yet the potential role of natural regenerators remains unclear. We test the hypothesis that the richness and functional diversity of terrestrial mammals differs between forest regrowth stages. We quantified the richness and functional diversity of eight terrestrial mammal seed-disperser species across a forest regrowth gradient in the eastern Brazilian Amazon. We installed camera-traps in 15 sites within small-holder properties with forest regrowth stage classified into three groups, with five sites each of: late second-regrowth forest, early second-regrowth forest and abandoned pasture. Species richness and functional dispersion from the regrowth sites were compared with 15 paired forest control sites. Multi model selection showed that regrowth class was more important for explaining patterns in richness and functional diversity than other variables from three non-mutually exclusive hypotheses: hunting (distance to house, distance to river, distance to town, small holder residence), land cover (% forest cover within 50 meters, 1 kilometer and 5 kilometers) and land use (regrowth class, time since last use). Differences in functional diversity were most strongly explained by a loss of body mass. We found that diversity in regrowth sites could be similar to control sites even in some early-second regrowth areas. This finding suggests that when surrounded by large intact forest areas the richness and functional diversity close to human small-holdings can return to pre-degradation values. Yet we also found a significant reduction in richness and functional diversity in more intensely degraded pasture sites. This reduction in richness and functional diversity may limit the potential for regeneration and increase costs for ecological regeneration and restoration actions around more intense regrowth areas. PMID:29547648

Diversity of terrestrial mammal seed dispersers along a lowland Amazon forest regrowth gradient.

PubMed

Arévalo-Sandi, Alexander; Bobrowiec, Paulo Estefano D; Rodriguez Chuma, Victor Juan Ulises; Norris, Darren

2018-01-01

There is increasing interest in the restoration/regeneration of degraded tropical habitats yet the potential role of natural regenerators remains unclear. We test the hypothesis that the richness and functional diversity of terrestrial mammals differs between forest regrowth stages. We quantified the richness and functional diversity of eight terrestrial mammal seed-disperser species across a forest regrowth gradient in the eastern Brazilian Amazon. We installed camera-traps in 15 sites within small-holder properties with forest regrowth stage classified into three groups, with five sites each of: late second-regrowth forest, early second-regrowth forest and abandoned pasture. Species richness and functional dispersion from the regrowth sites were compared with 15 paired forest control sites. Multi model selection showed that regrowth class was more important for explaining patterns in richness and functional diversity than other variables from three non-mutually exclusive hypotheses: hunting (distance to house, distance to river, distance to town, small holder residence), land cover (% forest cover within 50 meters, 1 kilometer and 5 kilometers) and land use (regrowth class, time since last use). Differences in functional diversity were most strongly explained by a loss of body mass. We found that diversity in regrowth sites could be similar to control sites even in some early-second regrowth areas. This finding suggests that when surrounded by large intact forest areas the richness and functional diversity close to human small-holdings can return to pre-degradation values. Yet we also found a significant reduction in richness and functional diversity in more intensely degraded pasture sites. This reduction in richness and functional diversity may limit the potential for regeneration and increase costs for ecological regeneration and restoration actions around more intense regrowth areas.

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. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

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...

Small mammal communities in eastern redcedar forest

USGS Publications Warehouse

Reddin, Christopher J.; Krementz, David G.

2016-01-01

Eastern redcedar (Juniperus virginiana) is a fire-intolerant tree species that has encroached into grassland ecosystems throughout central and eastern North America. Many land managers are interested in removing eastern redcedar to restore native grasslands. We surveyed small mammals using mark-recapture methods in eastern redcedar forest, warm-season grassland, and oldfield habitats in the Ozark region of northwest Arkansas. We conducted over 3300 trap-nights and captured 176 individuals belonging to eight small mammal species, primarily Peromyscus spp. and Reithrodonotmys fulvescens. While species diversity did not vary among habitats, small mammal species composition in eastern redcedar forest differed from that of warm-season grassland and oldfield habitats. The small mammal community of eastern redcedar forest is as diverse as the warm-season grasslands and oldfields it succeeds but replaces grassland associated small mammal species with forest associated species.

Small mammal responses to Amazonian forest islands are modulated by their forest dependence.

PubMed

Palmeirim, Ana Filipa; Benchimol, Maíra; Vieira, Marcus Vinícius; Peres, Carlos A

2018-05-01

Hydroelectric dams have induced widespread loss, fragmentation and degradation of terrestrial habitats in lowland tropical forests. Yet their ecological impacts have been widely neglected, particularly in developing countries, which are currently earmarked for exponential hydropower development. Here we assess small mammal assemblage responses to Amazonian forest habitat insularization induced by the 28-year-old Balbina Hydroelectric Dam. We sampled small mammals on 25 forest islands (0.83-1466 ha) and four continuous forest sites in the mainland to assess the overall community structure and species-specific responses to forest insularization. We classified all species according to their degree of forest-dependency using a multi-scale approach, considering landscape, patch and local habitat characteristics. Based on 65,520 trap-nights, we recorded 884 individuals of at least 22 small mammal species. Species richness was best predicted by island area and isolation, with small islands (< 15 ha) harbouring an impoverished nested subset of species (mean ± SD: 2.6 ± 1.3 species), whereas large islands (> 200 ha; 10.8 ± 1.3 species) and continuous forest sites (∞ ha; 12.5 ± 2.5 species) exhibited similarly high species richness. Forest-dependent species showed higher local extinction rates and were often either absent or persisted at low abundances on small islands, where non-forest-dependent species became hyper-abundant. Species capacity to use non-forest habitat matrices appears to dictate small mammal success in small isolated islands. We suggest that ecosystem functioning may be highly disrupted on small islands, which account for 62.7% of all 3546 islands in the Balbina Reservoir.

Detection and persistence of environmental DNA from an invasive, terrestrial mammal.

PubMed

Williams, Kelly E; Huyvaert, Kathryn P; Vercauteren, Kurt C; Davis, Amy J; Piaggio, Antoinette J

2018-01-01

Invasive Sus scrofa , a species commonly referred to as wild pig or feral swine, is a destructive invasive species with a rapidly expanding distribution across the United States. We used artificial wallows and small waterers to determine the minimum amount of time needed for pig eDNA to accumulate in the water source to a detectable level. We removed water from the artificial wallows and tested eDNA detection over the course of 2 weeks to understand eDNA persistence. We show that our method is sensitive enough to detect very low quantities of eDNA shed by a terrestrial mammal that has limited interaction with water. Our experiments suggest that the number of individuals shedding into a water system can affect persistence of eDNA. Use of an eDNA detection technique can benefit management efforts by providing a sensitive method for finding even small numbers of individuals that may be elusive using other methods.

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.

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.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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 avianmore » 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

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yunger, John A.

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 avianmore » 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 were 2-3x greater on exclusion plots relative to controls due to preferential selection of Microtus by canids, as reflected in diets. 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 £.. 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 .f.. leucopus spatial patterns mediated through M. pennsylvanicus. The role of food limitation was studied using natural and

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.

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

Movement patterns of riparian small mammals during predictable floodplain inundation

USGS Publications Warehouse

Andersen, D.C.; Wilson, K.R.; Miller, M.S.; Falck, M.

2000-01-01

We monitored movements of small mammals resident on floodplains susceptible to spring floods to assess whether and how these animals respond to habitat inundation. The 2 floodplains were associated with 6th order river segments in a semiarid landscape; each was predictably inundated each year as snowmelt progressed in headwater areas of the Rocky Mountains. Data from live trapping, radiotelemetry, and microtopographic surveys indicated that Peromyscus maniculatus, Microtus montanus, and Dipodomys ordii showed different responses to inundation, but all reflected a common tendency to remain in the original home range until “forced” to leave. The reluctance of Dipodomys ordii to abandon the home burrow often resulted in death in situ, whereas individual P. maniculatus and M. montanus moved to nearby higher ground but not necessarily toward upland. This behavior could lead to occupancy of an island that disappeared as floodwaters rose. Peromyscus maniculatus climbed into sapling cottonwood, but the quality of such arboreal refuges was unclear. We found only weak support for the hypothesis that displacement was temporary; most floodplain residents, including P. maniculatus, disappeared over the flood period. No secondary effect from flooding on adjacent upland small-mammal assemblages was detected. Our data suggest populations of facultatively riparian, nonarboreal small mammals such as M. montanus and D. ordii generally experience habitat inundation as a catastrophy. Terrestrial species capable of using an arboreal refuge, such as P. maniculatus, face a more variable risk, determined in part by timing and duration of the flood event. River regulation can affect both sets of risks.

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

PubMed

Lima, Fernando; Beca, Gabrielle; Muylaert, Renata L; Jenkins, Clinton N; Perilli, Miriam L L; Paschoal, Ana Maria O; Massara, Rodrigo L; Paglia, Adriano P; Chiarello, Adriano G; Graipel, Maurício E; Cherem, Jorge J; Regolin, André L; Oliveira Santos, Luiz Gustavo R; Brocardo, Carlos R; Paviolo, Agustín; Di Bitetti, Mario S; Scoss, Leandro M; Rocha, Fabiana L; Fusco-Costa, Roberto; Rosa, Clarissa A; Da Silva, Marina X; Hufnagell, Ludmila; Santos, Paloma M; Duarte, Gabriela T; Guimarães, Luiza N; Bailey, Larissa L; Rodrigues, Flávio Henrique G; Cunha, Heitor M; Fantacini, Felipe M; Batista, Graziele O; Bogoni, Juliano A; Tortato, Marco A; Luiz, Micheli R; Peroni, Nivaldo; De Castilho, Pedro V; Maccarini, Thiago B; Filho, Vilmar Picinatto; Angelo, Carlos De; Cruz, Paula; Quiroga, Verónica; Iezzi, María E; Varela, Diego; Cavalcanti, Sandra M C; Martensen, Alexandre C; Maggiorini, Erica V; Keesen, Fabíola F; Nunes, André V; Lessa, Gisele M; Cordeiro-Estrela, Pedro; Beltrão, Mayara G; De Albuquerque, Anna Carolina F; Ingberman, Bianca; Cassano, Camila R; Junior, Laury Cullen; Ribeiro, Milton C; Galetti, Mauro

2017-11-01

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, eight ungulates and six 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. © 2017 by the Ecological Society of America.

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...

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...

[Fleas on small mammals in the surrounding area of Erhai Lake].

PubMed

Dong, Wen-Ge; Guo, Xian-Guo; Men, Xing-Yuan; Gong, Zheng-Da; Wu, Dian; Zhang, Zheng-Kun; Zhang, Li-Yun

2009-12-01

To investigate the distribution pattern, species diversity and community structure of fleas on small mammals in the surrounding area of Erhai Lake, and the relationship between fleas and their hosts. Different geographical areas surrounding the Erhai Lake in Yunnan were selected as investigated spots. Small mammals were captured with baited cages. The cage-traps were examined and re-baited each morning. All fleas on the hosts were collected and identified. The richness (S), evenness (J'), diversity index (H'), dominance index (C'), total ectoparasite infestation rate (Rpt), total ectoparasite infestation index (Ipt), and constituent ratio (Cr) were used to measure the community structure. Altogether, 3,303 small mammals and 3,243 fleas were collected. From the 21 species of small mammal hosts, 13 species of fleas were identified. In southern area of the Lake, the species richness (21 species of small mammals & 12 species of fleas) was highest among the three selected areas. Seventeen species of small mammals and 8 species of fleas were found in eastern area, and only 13 species of small mammals and 7 species of fleas found in the west. This implied the probable influences of ecological environments on the fleas and their corresponding hosts. The community structure of fleas on small mammals was complex. The species diversity, species composition, community structure and distribution pattern of fleas were simultaneously influenced by the hosts' body surface microenvironment and the macroenvironment (habitat). The fleas are commonly distributed in small mammals in the areas and their communities are related to host species and the habitats.

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.

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

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.

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

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�

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...

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

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.

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

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...

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.

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

A comparison of small-mammal communities in a desert riparian floodplain

USGS Publications Warehouse

Ellison, Laura E.; van Riper, Charles

1998-01-01

We compared small-mammal communities between inactive floodplain and actively flooded terraces of riparian habitat in the Verde Valley of central Arizona. We used species diversity, abundance, weight of adult males, number of juveniles, number of reproductively active individuals, longevity, residency status, and patterns of microhabitat use to compare the two communities. Although abundances of small mammals tended to be higher in the active floodplain, species diversity was greater in the inactive floodplain. Results were inconsistent with our initial prediction that actively flooded riparian habitat acts as a species source, whereas inactive floodplain acts as a sink or dispersal site for small mammals. Within each habitat type, we found evidence of significant microhabitat separation among the three most abundant small-mammal species (Peromyscus boylii, P. eremicus, and Neotoma albigula). Percent cover by annual and perennial grasses and shrubs, substrate, and frequency of shrubs, trees, and debris were significant determinants of small-mammal distribution within a habitat type. We found that the three most abundant species selected a nonrandom subset of available habitat. Nonrandom use of habitat and microhabitat separation were the two most important mechanisms structuring small-mammal communities in riparian habitat of central Arizona.

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...

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....

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

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...

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.

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

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 grasslandmore » 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.« less

Small mammal abundance in Mediterranean post-fire habitats: a role for predators?

NASA Astrophysics Data System (ADS)

Torre, I.; Díaz, M.

2004-05-01

We studied patterns of small mammal abundance and species richness in post-fire habitats by sampling 33 plots (225 m 2 each) representing different stages of vegetation recovery after fire. Small mammal abundance was estimated by live trapping during early spring 1999 and vegetation structure was sampled by visual estimation at the same plots. Recently-burnt areas were characterised by shrubby and herbaceous vegetation with low structural variability, and unburnt areas were characterised by well developed forest cover with high structural complexity. Small mammal abundance and species richness decreased with time elapsed since the last fire (from 5 to at least 50 years), and these differences were associated to the decreasing cover of short shrubs as the post-fire succession of plant communities advanced. However, relationships between vegetation structure and small mammals differed among areas burned in different times, with weak or negative relationship in recently burnt areas and positive and stronger relationship in unburnt areas. Furthermore, the abundance of small mammals was larger than expected from vegetation structure in plots burned recently whereas the contrary pattern was found in unburned areas. We hypothesised that the pattern observed could be related to the responses of small mammal predators to changes in vegetation and landscape structure promoted by fire. Fire-related fragmentation could have promoted the isolation of forest predators (owls and carnivores) in unburned forest patches, a fact that could have produced a higher predation pressure for small mammals. Conversely, small mammal populations would have been enhanced in early post-fire stages by lower predator numbers combined with better predator protection in areas covered by resprouting woody vegetation.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 amore » 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.« less

Role of small mammals in the epidemiology of toxocariasis.

PubMed

Dubinský, P; Havasiová-Reiterová, K; Petko, B; Hovorka, I; Tomasovicová, O

1995-02-01

Studies were conducted on the role of small mammals in maintaining toxocariasis foci in urban, rural and montane biotopes. The lowest relative density of small mammals was recorded in the urban locality and the highest in the rural and montane localities. Anti-Toxocara antibodies were most frequently detected in synanthropic and hemisynanthropic species Mus musculus, Apodemus agrarius and Micromys minutus--32.0, 30.4 and 25.0%, respectively. The highest seropositivity was found in small mammals from the urban and rural localities--22.2 and 21.6%, respectively. Toxocara canis was most prevalent in urban stray dogs (75.0%) and least prevalent in foxes from the montane locality (7.0%). The prevalence of Toxocara cati in cats at the urban, rural and montane localities was 66.2, 65.2 and 76.9%, respectively. In clinically healthy human populations, the highest seroprevalence was detected in the rural locality (14.0%). Children of the same area were 3 times more seropositive (12.9%) than those from the urban and montane localities (4.3 and 4.0%). Our studies suggest an important role for small mammals as paratenic hosts--reservoirs of Toxocara larvae--in maintaining toxocariasis foci. In this respect toxocariasis may be classified as an anthropopurgic focal zoonosis.

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....

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...

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.

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....

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

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.

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).

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...

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.

Larval Chigger Mites Collected from Small Mammals in 3 Provinces, Korea

PubMed Central

Lee, In-Yong; Song, Hyeon-Je; Choi, Yeon-Joo; Shin, Sun-Hye; Choi, Min-Kyung; Kwon, So-Hyun; Shin, E-Hyun; Park, Chan; Kim, Heung-Chul; Klein, Terry A.; Park, Kyung-Hee

2014-01-01

A total of 9,281 larval chigger mites were collected from small mammals captured at Hwaseong-gun, Gyeonggi-do (Province) (2,754 mites from 30 small mammals), Asan city, Chungcheongnam-do (3,358 mites from 48 mammals), and Jangseong-gun, Jeollanam-do (3,169 for 62 mammals) from April-November 2009 in the Republic of Korea (= Korea) and were identified to species. Leptotrombidium pallidum was the predominant species in Hwaseong (95.8%) and Asan (61.2%), while Leptotrombidium scutellare was the predominant species collected from Jangseong (80.1%). Overall, larval chigger mite indices decreased from April (27.3) to June (4.9), then increased in September (95.2) and to a high level in November (169.3). These data suggest that L. pallidum and L. scutellare are the primary vectors of scrub typhus throughout their range in Korea. While other species of larval chigger mites were also collected with some implications in the transmission of Orientia tsutsugamushi, they only accounted for 11.2% of all larval chigger mites collected from small mammals. PMID:24850971

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...

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.

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.

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.

SMALL MAMMAL BIOCLIMATE STUDIES IN NORTHERN REGIONS

DTIC Science & Technology

northern regions. Two major divisions are established - the tundra (arctic treeless region) and the taiga (subarctic spruce forest). Further subdivisions...of taiga small mammals are analyzed. Points of potential value to the Air Force are drawn from studies on the importance of topographical

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...

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...

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.

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-...

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...

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.

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...

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

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.

A tribosphenic mammal from the Mesozoic of Australia.

PubMed

Rich, T H; Vickers-Rich, P; Constantine, A; Flannery, T F; Kool, L; van Klaveren, N

1997-11-21

A small, well-preserved dentary of a tribosphenic mammal with the most posterior premolar and all three molars in place has been found in Aptian (Early Cretaceous) rocks of southeastern Australia. In most respects, dental and mandibular anatomy of the specimen is similar to that of primitive placental mammals. With the possible exception of a single tooth reported as Eocene in age, terrestrial placentals are otherwise unknown in Australia until the Pliocene. This possible Australian placental is similar in age to Prokennalestes from the late Aptian/early Albian Khoboor Beds of Mongolia, the oldest currently accepted member of the infraclass Placentalia.

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.

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...

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.

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.

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...

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.

High Prevalence of Rickettsia spp. Infections in Small Mammals in Taiwan

PubMed Central

Kuo, Chi-Chien; Shu, Pei-Yun; Mu, Jung-Jung

2015-01-01

Abstract 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. PMID:25629776

Biota dose assessment of small mammals sampled near uranium mines in northern Arizona

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jannik, T.; Minter, K.; Kuhne, W.

In 2015, the U. S. Geological Survey (USGS) collected approximately 50 small mammal carcasses from Northern Arizona uranium mines and other background locations. Based on the highest gross alpha results, 11 small mammal samples were selected for radioisotopic analyses. None of the background samples had significant gross alpha results. The 11 small mammals were identified relative to the three ‘indicator’ mines located south of Fredonia, AZ on the Kanab Plateau (Kanab North Mine, Pinenut Mine, and Arizona 1 Mine) (Figure 1-1) and are operated by Energy Fuels Resources Inc. (EFRI). EFRI annually reports soil analysis for uranium and radium-226 usingmore » Arizona Department of Environmental Quality (ADEQ)-approved Standard Operating Procedures for Soil Sampling (EFRI 2016a, 2016b, 2017). In combination with the USGS small mammal radioiosotopic tissue analyses, a biota dose assessment was completed by Savannah River National Laboratory (SRNL) using the RESidual RADioactivity-BIOTA (RESRAD-BIOTA, V. 1.8) dose assessment tool provided by the Argonne National Laboratory (ANL 2017).« less

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...

Two decades of climate driving the dynamics of functional and taxonomic diversity of a tropical small mammal community in western Mexico

PubMed Central

2017-01-01

Understanding the effects of global climate disruption on biodiversity is important to future conservation efforts. While taxonomic diversity is widely studied, functional diversity of plants, and recently animals, is receiving increasing attention. Most studies of mammals are short-term, focus on temperate habitats, and rely on traits described in the literature rather than generating traits from observations. Unlike previous studies, this long-term field study assessed the factors driving the functional and taxonomic diversity of small-mammal assemblages in dry tropical forests using both traits recorded from literature and a demographic database. We assessed the drivers (abundance and biomass, temperature and rainfall) of taxonomic richness and functional diversity for two rain-driven seasons in two adjacent but distinct forests—upland and lowland (arroyo or riparian) forests. Our analysis found that rainfall, both seasonal and atypical, was the primary factor driving functional and taxonomic diversity of small-mammal assemblages. Functional responses differed between the two types of forests, however, with effects being stronger in the harsher conditions of the upland forests than in the less severe conditions prevailing in the arroyo (riparian) forest. The latter also supports a richer, more diverse, and more stable small-mammal assemblage. These findings highlight the importance of climate to tropical biological diversity, as extreme climate events (hurricanes, droughts and floods) and disruption of rainfall patterns were shown to decrease biodiversity. They also support the need to preserve these habitats, as their high taxonomic diversity and functional redundancy makes them resilient against global climate disruption and local extreme events. Tropical dry forests constitute a potential reservoir for biodiversity and the ecosystem services they provide. Unfortunately, these forests are among the most endangered terrestrial ecosystems because of

Two decades of climate driving the dynamics of functional and taxonomic diversity of a tropical small mammal community in western Mexico.

PubMed

Mason-Romo, Edgard David; Farías, Ariel A; Ceballos, Gerardo

2017-01-01

Understanding the effects of global climate disruption on biodiversity is important to future conservation efforts. While taxonomic diversity is widely studied, functional diversity of plants, and recently animals, is receiving increasing attention. Most studies of mammals are short-term, focus on temperate habitats, and rely on traits described in the literature rather than generating traits from observations. Unlike previous studies, this long-term field study assessed the factors driving the functional and taxonomic diversity of small-mammal assemblages in dry tropical forests using both traits recorded from literature and a demographic database. We assessed the drivers (abundance and biomass, temperature and rainfall) of taxonomic richness and functional diversity for two rain-driven seasons in two adjacent but distinct forests-upland and lowland (arroyo or riparian) forests. Our analysis found that rainfall, both seasonal and atypical, was the primary factor driving functional and taxonomic diversity of small-mammal assemblages. Functional responses differed between the two types of forests, however, with effects being stronger in the harsher conditions of the upland forests than in the less severe conditions prevailing in the arroyo (riparian) forest. The latter also supports a richer, more diverse, and more stable small-mammal assemblage. These findings highlight the importance of climate to tropical biological diversity, as extreme climate events (hurricanes, droughts and floods) and disruption of rainfall patterns were shown to decrease biodiversity. They also support the need to preserve these habitats, as their high taxonomic diversity and functional redundancy makes them resilient against global climate disruption and local extreme events. Tropical dry forests constitute a potential reservoir for biodiversity and the ecosystem services they provide. Unfortunately, these forests are among the most endangered terrestrial ecosystems because of

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.

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.

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,...

Corridors and olfactory predator cues affect small mammal behavior.

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 connectedmore » 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.« less

A cross-sectional study of small mammals for tick-borne pathogen infection in northern Mongolia.

PubMed

Pulscher, Laura A; Moore, Thomas C; Caddell, Luke; Sukhbaatar, Lkhagvatseren; von Fricken, Michael E; Anderson, Benjamin D; Gonchigoo, Battsetseg; Gray, Gregory C

2018-01-01

Background : Tick-borne pathogens (TBPs) are frequently studied in developed nations but are often neglected in emerging countries. In Mongolia, TBP research is especially sparse, with few research reports focusing upon human and domestic animal disease and tick ecology. However, little information exists on TBPs in small mammals. Methods : In this 2016 cross-sectional pilot study, we sought to uniquely study wildlife for TBPs. We live-trapped small mammals, and tested their whole blood, serum and ear biopsy samples for molecular or serological evidence of Borrelia spp., Rickettsia spp., and Anaplasma spp. /Ehrlichia spp. Results : Of 64 small mammals collected, 56.0%, 39.0% and 0.0% of animals were positive by molecular assays for Borrelia spp., Rickettsia spp., and Anaplasma spp. /Erhlicia spp., respectively. 41.9% were seropositive for A. phagocytophilum and 24.2% of animals were seropositive for Rickettsia rickettsii . Conclusion : This pilot data demonstrates evidence of a number of TBPs among small mammal populations in northern Mongolia and suggests the need to further investigate what role these mammals play in human and domestic animal disease.

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

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; (...

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

DTIC Science & Technology

2010-01-01

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

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.

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...

Small-mammal seed predation limits the recruitment and abundance of two perennial grassland forbs.

PubMed

Bricker, Mary; Pearson, Dean; Maron, John

2010-01-01

Although post-dispersal seed predators are common and often reduce seed density, their influence on plant population abundance remains unclear. On the one hand, increasing evidence suggests that many plant populations are seed limited, implying that seed predators could reduce plant abundance. On the other hand,.it is generally uncertain whether the magnitude of seed limitation imposed by granivores is strong enough to overcome density-dependent processes that could compensate for seed loss at later stages. We examined the impact of seed predation by small mammals, primarily deer mice (Peromyscus maniculatus), on seedling recruitment and subsequent plant establishment of two perennial grassland forbs in western Montana, USA: Lupinus sericeus (Fabaceae) and Lithospermum ruderale (Boraginaceae). The experiment combined graded densities of seed addition for each species with a small-mammal exclusion treatment. Seedling recruitment and plant establishment were monitored in the experimental plots for up to three years. For both species, small-mammal exclusion increased the total number of seedlings that emerged, and these effects were still significant three years after seed addition, resulting in greater numbers of established plants inside exclosures than in control plots. We also found evidence of seed limitation, with increasing density of seeds added leading to increased numbers of seedlings. Results from seed addition and small-mammal exclusion experiments in later years also revealed significant impacts of small mammals on seedling emergence. These results suggest that granivores can have potentially important impacts in limiting forb abundance in grasslands communities.

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

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.

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

Borrelia burgdorferi in small mammal reservoirs in Kentucky, a traditionally non-endemic state for Lyme disease.

PubMed

Buchholz, Matthew J; Davis, Cheryl; Rowland, Naomi S; Dick, Carl W

2018-04-01

The incidence of tick-borne zoonoses such as Lyme disease has steadily increased in the southeastern United States. Southeastern states accounted for 1500 of over 28,000 confirmed cases of Lyme disease reported in the United States during 2015. Borrelia burgdorferi, the etiologic agent of Lyme disease, is maintained in small mammal reservoirs and vectored to new hosts by ixodid ticks. This study examined ecological relationships of the B. burgdorferi/vector/reservoir system in order to understand the dynamics of Lyme disease risk in Kentucky. Small mammals were captured using live traps from November 2014 to October 2015. Ticks were removed and blood and tissue collected from small mammals were screened for B. burgdorferi DNA by PCR with primers specific to the OspA gene. Prevalence of B. burgdorferi (21.8%) in Kentucky small mammals was comparable to the lowest recorded prevalence in regions where Lyme disease is endemic. Moreover, infestation of small mammals by Ixodes scapularis, the primary vector of B. burgdorferi, was rare, while Dermacentor variabilis comprised the majority of ticks collected. These findings provide ecological insight into the relative paucity of Lyme disease in Kentucky.

Drivers of Echinococcus multilocularis transmission in China: small mammal diversity, landscape or climate?

PubMed

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

2013-01-01

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. 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 km(2) region. 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 to predict human disease risk and for controlling this

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

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. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

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.

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...

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.

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.

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.

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.

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...

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...

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.

Arctic terrestrial ecosystem contamination.

PubMed

Thomas, D J; Tracey, B; Marshall, H; Norstrom, R J

1992-07-15

Limited data have been collected on the presence of contaminants in the Arctic terrestrial ecosystem, with the exception of radioactive fallout from atmospheric weapons testing. Although southern and temperate biological systems have largely cleansed themselves of radioactive fallout deposited during the 1950s and 1960s, Arctic environments have not. Lichens accumulate radioactivity more than many other plants because of their large surface area and long life span; the presence and persistence of radioisotopes in the Arctic is of concern because of the lichen----reindeer----human ecosystem. Effective biological half-life of cesium 137 is reckoned to be substantially less than its physical half-life. The database on organochlorines in Canadian Arctic terrestrial mammals and birds is very limited, but indications are that the air/plant/animal contaminant pathway is the major route of these compounds into the terrestrial food chain. For terrestrial herbivores, the most abundant organochlorine is usually hexachlorobenzene followed by hexachlorocyclohexane isomers. PCB accumulation favours the hexachlorobiphenyl, pentachlorobiphenyl and heptachlorobiphenyl homologous series. The concentrations of the various classes of organochlorine compounds are substantially lower in terrestrial herbivore tissues than in marine mammal tissues. PCBs and DDT are the most abundant residues in peregrine falcons (a terrestrial carnivore) reaching average levels of 9.2 and 10.4 micrograms.g-1, respectively, more than 10 times higher than other organochlorines and higher than in marine mammals, including the polar bear. Contaminants from local sources include metals from mining activities, hydrocarbons and waste drilling fluids from oil and gas exploration and production, wastes from DEW line sites, naturally occurring radionuclides associated with uranium mineralization, and smoke containing SO2 and H2SO4 aerosol from the Smoking Hills at Cape Bathurst, N.W.T.

Presence of Helicobacter and Campylobacter species in faecal samples from zoo mammals.

PubMed

De Witte, C; Lemmens, C; Flahou, B; De Laender, P; Bouts, T; Vercammen, F; Ducatelle, R; Smet, A; Haesebrouck, F

2018-06-01

Helicobacter and Campylobacter species (spp.) colonize the gastrointestinal tract of various domesticated animals. Apart from their pathogenic significance in animals, several species are of zoonotic importance as well. For most non-domesticated animal spp., however, little is known on the presence and importance of these agents. Therefore, we investigated the presence of Helicobacter and Campylobacter spp. in marine and terrestrial zoo mammals. Faecal samples of various marine and terrestrial zoo mammals were collected from 6 different zoos in Belgium. These samples were tested for the presence of Helicobacter and Campylobacter spp. by isolation and direct demonstration of DNA using genus-specific PCRs, followed by sequencing of the obtained amplicons. Helicobacter spp. were detected in 12 and Campylobacter spp. in 5 of the 22 faecal samples from marine mammals. In 4 of 5 dolphins, H. cetorum was demonstrated, a well-known pathogen associated with gastritis and gastric ulceration in marine mammals. C. insulaenigrae was isolated from 4 of 6 sea lions and from 1 of 11 seals. To our knowledge, this is the first description of the presence of C. insulaenigrae on the European mainland. Helicobacter spp. were detected in 5 and Campylobacter spp. (mainly C. jejuni subsp. jejuni and C. coli) in 9 of the 26 faecal samples from terrestrial mammals. Potential novel enterohepatic Helicobacter spp. were detected in both marine and terrestrial zoo mammals. For the first time, the presence of several known and unknown Campylobacter and Helicobacter spp. was demonstrated in the gastrointestinal tract of various marine and terrestrial zoo mammals. Further investigation is needed on the pathogenic and zoonotic importance of these species. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

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.

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. Copyright © 2016 Elsevier GmbH. All rights reserved.

Wide Distribution and Genetic Diversity of Babesia microti in Small Mammals from Yunnan Province, Southwestern China.

PubMed

Gao, Zi-Hou; Huang, Tao-Hua; Jiang, Bao-Gui; Jia, Na; Liu, Zheng-Xiang; Shao, Zong-Ti; Jiang, Rui-Ruo; Liu, Hong-Bo; Wei, Ran; Li, Yu-Qiong; Yao, Hong-Wu; von Fricken, Michael E; Jiang, Jia-Fu; Du, Chun-Hong; Cao, Wu-Chun

2017-10-01

Babesia, usually found in wild and domestic mammals worldwide, have recently been responsible for emerging malaria-like zoonosis in infected patients. Human B. microti infection has been identified in China, primarily in the Southwest along the Myanmar border but little direct surveillance of B. microti infection in rodents has been carried out here (Yunnan province). In this region, a diverse topographic range combined with tropical moisture sustains a high biodiversity of small mammals, which might play important role on Babesia transmission. Small mammals were captured in 141 sample locations from 18 counties located Yunnan Province, and screened for B. microti-like parasites infection by a nested PCR to target 18S rRNA gene of Babesia, plus directly sequencing for positive samples. Univariate and multivariate forward stepwise logistic regression analysis was used to access the association between infections and some related risk factors. Infection with Babesia microti was confirmed in 2.4% (53/ 2204) of small mammals. Significant differences in prevalence rates of B. microti were observed based on variations in forest, agricultural, and residential landscapes. Furthermore, adult small mammals had higher prevalence rates than younger, pubertal mammals. The near full-length 18S rRNA gene revealed that there were two types of B. microti, Kobe and Otsu, which demonstrate the genetic diversity and regional distribution. There exists a wide distribution and genetic diversity of endemic B. microti in Southwestern China, warranting further investigations and monitoring of clinical disease in individuals presenting with Babesia like symptoms in these areas.

Osteoarthritis in two marine mammals and 22 land mammals: learning from skeletal remains.

PubMed

Nganvongpanit, Korakot; Soponteerakul, Ratsadakorn; Kaewkumpai, Piyatida; Punyapornwithaya, Veerasak; Buddhachat, Kittisak; Nomsiri, Raksiri; Kaewmong, Patcharaporn; Kittiwatanawong, Kongkiat; Chawangwongsanukun, Rachanchai; Angkawanish, Taweepoke; Thitaram, Chatchote; Mahakkanukrauh, Pasuk

2017-07-01

The occurrence of osteoarthritis (OA) in marine mammals is still questionable. Here we investigated the prevalence of OA in marine (dolphin and dugong) and terrestrial mammals (Asian elephant, Asiatic buffalo, camel, cat, cattle, deer, dog, domestic goat, horse, human, hyena, impala, lion, Malayan tapir, Assam macaque, mule, pig, rabbit, red kangaroo, sheep, tiger and waterbuck). Skeletal remains obtained from five institutes were used as subjects; a total of 45 different parts (locations) of bones were observed for OA lesions. The prevalence of OA was reported as number of OA lesions/total number of bones. Our results revealed that the presence of OA in marine species (dolphin and dugong) was 2.44% and 3.33%, respectively. In dolphins, the highest OA occurrence was on the left and right humeral trochlea, with 13.68% and 12.63%, respectively, while the highest number of OA lesions in dugongs was on the lumbar vertebrae (8.79%). No significant difference (P > 0.05) in the prevalence of OA between sexes in dolphins and dugongs was observed, but we found a significant difference (P < 0.05) in 24 bone locations of human bones, which had the highest OA prevalence (48.93%), followed by dogs (3.94%). In conclusion, OA can occur in marine mammals, similar to terrestrial mammals, even though their natural habitat is the ocean. © 2017 Anatomical Society.

Natural History of Oregon Coast Mammals

Treesearch

Chris Maser; Bruce R. Mate; Jerry F. Franklin; C.T. Dyrness

1981-01-01

The book presents detailed information on the biology, habitats, and life histories of the 96 species of mammals of the Oregon coast. Soils, geology, and vegetation are described and related to wildlife habitats for the 65 terrestrial and 31 marine species. The book is not simply an identification guide to the Oregon coast mammals but is a dynamic portrayal of their...

Constitutional basis of longevity in the cetacea: do the whales and the terrestrial mammals obey the same laws

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sacher, G.A.

1978-01-01

The maximum lifespans in captivity for terrestrial mammalian species can be estimated by means of a multiple linear regression of logarithm of lifespan (L) on the logarithm of adult brain weight (E) and body weight (S). This paper describes the application of regression formulas based on data from terrestrial mammals to the estimation of odontocete and mysticete lifespans. The regression formulas predict cetacean lifespans that are in accord with the data on maximum cetacean lifespans obtained in recent years by objective age determination procedures. More remarkable is the correct prediction by the regression formulas that the odontocete species have nearlymore » constant lifespans, almost independent of body weight over a 300:1 body weight range. This prediction is a consequence of the fact, remarkable in itself, that over this body weight range the Odontoceti have a brain:body allometric slope of 1/3, as compared to a slope of 2/3 for the Mammalia as a whole.« less

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...

Small species indicate big changes? Arctic report card

USDA-ARS?s Scientific Manuscript database

As Arctic climate warms, how will terrestrial ecosystems and the communities that they support respond in the coming decades? Small mammals including shrews and their associated parasites can serve as key indicators and proxies of accelerating perturbation, contributing to general models for anticip...

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.

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...

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...

Introduction to mammals of the South. Chapter 1

Treesearch

Margaret K. Trani; W. Mark Ford; Brian R. Chapman

2007-01-01

The South has an impressive diversity of mammal associations and terrestrial communities. These communities range from montane spruce-fir forests to tropical hardwoods and from coastal dunes to dry prairies. Centuries of settlement and land use change have shaped and modified the mammal communities observed in the South today.

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...

Cardiovascular Drugs in Avian, Small Mammal, and Reptile Medicine.

PubMed

Fitzgerald, Brenna Colleen; Dias, Sara; Martorell, Jaume

2018-05-01

Cardiovascular disease, including congestive heart failure, pericardial disease, and atherosclerosis, is becoming increasingly better recognized in companion birds, small mammals, and reptiles. A wide range of medications is available to treat these conditions, including diuretics, vasodilators, positive and negative inotropes, antiarrhythmic agents, and pentoxifylline. This review systematically discusses each of these drug classes and their potential applications in exotic species. Although treatment approaches remain largely empirical and extrapolated from small animal and human medicine, the management strategies presented here have the potential to both maintain quality of life and extend survival time for the exotic cardiac patient. Copyright © 2018 Elsevier Inc. All rights reserved.

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

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, Heather 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.

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...

Physiological and behavioral responses of an arboreal mammal to smoke and charcoal-ash substrate.

PubMed

Nowack, Julia; Stawski, Clare; Körtner, Gerhard; Geiser, Fritz

2018-02-01

The recent observation that torpor plays a key role in post-fire survival has been mainly attributed to the reduced food resources after fires. However, some of these adjustments can be facilitated or amplified by environmental changes associated with fires, such as the presence of a charcoal-ash substrate. In a previous experiment on a small terrestrial mammal the presence of charcoal and ash linked to food restriction intensified torpor use. However, whether fire cues also act as a trigger of torpor use when food is available and whether they affect other species including arboreal mammals remains elusive. To evaluate whether smoke, charcoal and ash can act as proximate triggers for an impending period of food shortage requiring torpor for mammals, we conducted an experiment on captive sugar gliders (Petaurus breviceps), a small, arboreal marsupial, housed in outside aviaries under different food regimes and natural ambient conditions. When food was available, fire simulation via exposure to smoke and charcoal-ash substrate caused a significant earlier start of activity and a significant decrease in resting body temperature. In contrast, only when food was withheld, did smoke and charcoal-ash exposure significantly enhance torpor depth and duration. Thus, our study not only provides evidence that fire simulation does affect arboreal and terrestrial species similarly, but also suggests that smoke and ash were presumably selected as cues for torpor induction because they indicate an impending lack of food. Copyright © 2017 Elsevier Inc. All rights reserved.

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.

Ancient ecology of 15-million-year-old browsing mammals within C3 plant communities from Panama.

PubMed

MacFadden, Bruce J; Higgins, Pennilyn

2004-06-01

Middle Miocene mammals are known from approximately 15 million-year-old sediments exposed along the Panama Canal of Central America, a region that otherwise has an exceedingly poor terrestrial fossil record. These land mammals, which represent a part of the ancient terrestrial herbivore community, include an oreodont Merycochoerus matthewi, small camel-like protoceratid artiodactyl Paratoceras wardi, two horses Anchitherium clarencei and Archaeohippus sp., and two rhinos Menoceras barbouri and Floridaceras whitei. Bulk and serial carbon and oxygen isotope analyses of the tooth enamel carbonate allow reconstruction of the ancient climate and ecology of these fossil mammals. Ancient Panama had an equable climate with seasonal temperature and rainfall fluctuations less than those seen today. The middle Miocene terrestrial community consisted predominantly, or exclusively, of C3 plants, i.e., there is no evidence for C4 grasses. Statistically different mean carbon isotope values for the mammalian herbivores indicate niche partitioning of the C3 plant food resources. The range of individual carbon isotope analyses, i.e., delta13C from -15.9 to -10.1 per thousand, indicates herbivores feeding on diverse plants from different habitats with extrapolated delta13C values of -29.9 to -24.2 per thousand, possibly ranging from dense forest to more open country woodland. The ecological niches of individual mammalian herbivore species were differentiated either by diet or body size.

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.

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.

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

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.

Optimising Camera Traps for Monitoring Small Mammals

PubMed Central

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 ( Mustela erminea ), feral cats (Felis catus) and hedgehogs ( Erinaceus europaeus ). 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. PMID:23840790

Bushmeat hunting and extinction risk to the world's mammals

PubMed Central

Abernethy, Katharine; Betts, Matthew G.; Chapron, Guillaume; Dirzo, Rodolfo; Galetti, Mauro; Levi, Taal; Lindsey, Peter A.; Macdonald, David W.; Machovina, Brian; Peres, Carlos A.; Wallach, Arian D.

2016-01-01

Terrestrial mammals are experiencing a massive collapse in their population sizes and geographical ranges around the world, but many of the drivers, patterns and consequences of this decline remain poorly understood. Here we provide an analysis showing that bushmeat hunting for mostly food and medicinal products is driving a global crisis whereby 301 terrestrial mammal species are threatened with extinction. Nearly all of these threatened species occur in developing countries where major coexisting threats include deforestation, agricultural expansion, human encroachment and competition with livestock. The unrelenting decline of mammals suggests many vital ecological and socio-economic services that these species provide will be lost, potentially changing ecosystems irrevocably. We discuss options and current obstacles to achieving effective conservation, alongside consequences of failure to stem such anthropogenic mammalian extirpation. We propose a multi-pronged conservation strategy to help save threatened mammals from immediate extinction and avoid a collapse of food security for hundreds of millions of people. PMID:27853564

Annual and spatial variation in composition and activity of terrestrial mammals on two replicate plots in lowland forest of eastern Ecuador

PubMed Central

Loiselle, Bette A.

2018-01-01

Terrestrial mammals are important components of lowland forests in Amazonia (as seed dispersal agents, herbivores, predators) but there are relatively few detailed studies from areas that have not been affected by human activities (e.g., hunting, logging). Yet, such information is needed to evaluate effects of humans elsewhere. We used camera traps to sample medium to large-sized terrestrial mammals at a site in lowland forests of eastern Ecuador, one of the most biologically rich areas in the world. We deployed cameras on two study plots in terra firme forest at Tiputini Biodiversity Station. Sixteen cameras were arranged 200 m apart in a 4 × 4 grid on each plot. Cameras were operated for  60 days in January–March, 2014–2017, for a total of 3,707 and 3,482 trap-days on the two plots (Harpia, Puma). A total of 28 species were recorded; 26 on Harpia and 25 on Puma. Number of species recorded each year was slightly greater on Harpia whereas overall capture rates (images/100 trap-days) were higher on Puma. Although most species were recorded on each plot, differences in capture rates meant that yearly samples on a given plot were more similar to each other than to samples on the other plot. Images of most species showed a clumped distribution pattern on each plot; Panthera onca was the only species that did not show a clumped distribution on either plot. Images at a given camera location showed no evidence of autocorrelation with numbers of images at nearby camera locations, suggesting that species were responding to small-scale differences in habitat conditions. A redundancy analysis showed that environmental features within 50 or 100 m of camera locations (e.g., elevation, variation in elevation, slope, distance to streams) accounted for significant amounts of variation in distribution patterns of species. Composition and relative importance based on capture rates were very similar to results from cameras located along trails at the same site; similarities

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...

Landscapes with different biodiversity influence distribution of small mammals and their ectoparasitic chigger mites: A comparative study from southwest China.

PubMed

Peng, Pei-Ying; Guo, Xian-Guo; Jin, Dao-Chao; Dong, Wen-Ge; Qian, Ti-Jun; Qin, Feng; Yang, Zhi-Hua; Fan, Rong

2018-01-01

From a previous field investigation in Yunnan, southwest China between 2001 and 2015, we selected two types of landscapes to make a retrospectively comparative study on the distribution of small mammals and their ectoparasitic chigger mites. One landscape is "mountainous uncultivated land (MUL)" with higher biodiversity, which is located in a famous "World Nature Heritage Site", the Three-Parallel-Rivers Region in the northwest of Yunnan. The other is "cultivated flatland landscape (CFL)" with lower biodiversity, which is located in the south of Yunnan. The landscapes with different biodiversity apparently influenced the distribution of small mammals and their ectoparasitic chigger mites. Much more species of small mammals and mites were found in MUL than in CFL. A total of 3,177 small mammals captured from MUL were identified as 55 species, 30 genera and 10 families in five orders. From these small mammal hosts, 5,882 chigger mites were collected and identified as 127 species, 15 genera and 3 subfamilies in two families. A total of 1,112 small mammals captured from CFL were identified as 19 species, 12 genera and 5 families in three orders. From these hosts, 17,742 chiggers were collected and identified as 86 species, 12 genera and 3 subfamilies in two families. Both the species diversity (S = 55) and community diversity (H = 2.673) of small mammals in MUL were much higher than those in CFL (S = 19; H = 0.926). There were also higher values of β diversity in MUL than in CFL. Different main reservoir rodent hosts of zoonoses (including tsutsugamushi disease) were found in two types of landscapes. Rattus tanezumi (one main reservoir host) was most abundant in CFL, which accounted for 80.22% of all the small mammals. Another two main reservoir hosts, Eothenomys miletus and Apodemus chevrieri were the dominant species in MUL, but they were not as abundant as R. tanezumi in CFL. Different vector species of chigger mites also existed in MUL and CFL. Leptotrombidium

Landscapes with different biodiversity influence distribution of small mammals and their ectoparasitic chigger mites: A comparative study from southwest China

PubMed Central

Peng, Pei-Ying; Jin, Dao-Chao; Dong, Wen-Ge; Qian, Ti-Jun; Qin, Feng; Yang, Zhi-Hua; Fan, Rong

2018-01-01

From a previous field investigation in Yunnan, southwest China between 2001 and 2015, we selected two types of landscapes to make a retrospectively comparative study on the distribution of small mammals and their ectoparasitic chigger mites. One landscape is “mountainous uncultivated land (MUL)” with higher biodiversity, which is located in a famous “World Nature Heritage Site”, the Three-Parallel-Rivers Region in the northwest of Yunnan. The other is “cultivated flatland landscape (CFL)” with lower biodiversity, which is located in the south of Yunnan. The landscapes with different biodiversity apparently influenced the distribution of small mammals and their ectoparasitic chigger mites. Much more species of small mammals and mites were found in MUL than in CFL. A total of 3,177 small mammals captured from MUL were identified as 55 species, 30 genera and 10 families in five orders. From these small mammal hosts, 5,882 chigger mites were collected and identified as 127 species, 15 genera and 3 subfamilies in two families. A total of 1,112 small mammals captured from CFL were identified as 19 species, 12 genera and 5 families in three orders. From these hosts, 17,742 chiggers were collected and identified as 86 species, 12 genera and 3 subfamilies in two families. Both the species diversity (S = 55) and community diversity (H = 2.673) of small mammals in MUL were much higher than those in CFL (S = 19; H = 0.926). There were also higher values of β diversity in MUL than in CFL. Different main reservoir rodent hosts of zoonoses (including tsutsugamushi disease) were found in two types of landscapes. Rattus tanezumi (one main reservoir host) was most abundant in CFL, which accounted for 80.22% of all the small mammals. Another two main reservoir hosts, Eothenomys miletus and Apodemus chevrieri were the dominant species in MUL, but they were not as abundant as R. tanezumi in CFL. Different vector species of chigger mites also existed in MUL and CFL

The dead do not lie: using skeletal remains for rapid assessment of historical small-mammal community baselines

PubMed Central

Terry, Rebecca C.

2010-01-01

Conservation and restoration efforts are often hindered by a lack of historical baselines that pre-date intense anthropogenic environmental change. In this paper I document that natural accumulations of skeletal remains represent a potential source of high-quality data on the historical composition and structure of small-mammal communities. I do so by assessing the fidelity of modern, decadal and centennial-scale time-averaged samples of skeletal remains (concentrated by raptor predation) to the living small-mammal communities from which they are derived. To test the power of skeletal remains to reveal baseline shifts, I employ the design of a natural experiment, comparing two taphonomically similar Great Basin cave localities in areas where anthropogenic land-use practices have diverged within the last century. I find relative stasis at the undisturbed site, but document rapid restructuring of the small-mammal community at the site subjected to recent disturbance. I independently validate this result using historical trapping records to show that dead remains accurately capture both the magnitude and direction of this baseline shift. Surveys of skeletal remains therefore provide a simple, powerful and rapid alternative approach for gaining insight into the historical structure and dynamics of modern small-mammal communities. PMID:20031992

[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.

Characterization of phylogenetically diverse astroviruses of marine mammals.

PubMed

Rivera, Rebecca; Nollens, Hendrik H; Venn-Watson, Stephanie; Gulland, Frances M D; Wellehan, James F X

2010-01-01

Astroviruses are small, non-enveloped, positive-stranded RNA viruses. Previously studied mammalian astroviruses have been associated with diarrhoeal disease. Knowledge of astrovirus diversity is very limited, with only six officially recognized astrovirus species from mammalian hosts and, in addition, one human and some bat astroviruses were recently described. We used consensus PCR techniques for initial identification of five astroviruses of marine mammals: three from California sea lions (Zalophus californianus), one from a Steller sea lion (Eumetopias jubatus) and one from a bottlenose dolphin (Tursiops truncatus). Bayesian and maximum-likelihood phylogenetic analysis found that these viruses showed significant diversity at a level consistent with novel species. Astroviruses that we identified from marine mammals were found across the mamastrovirus tree and did not form a monophyletic group. Recombination analysis found that a recombination event may have occurred between a human and a California sea lion astrovirus, suggesting that both lineages may have been capable of infecting the same host at one point. The diversity found amongst marine mammal astroviruses and their similarity to terrestrial astroviruses suggests that the marine environment plays an important role in astrovirus ecology.

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,...

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

The land manager's guide to mammals of the South

Treesearch

Margaret K. Trani; W. Mark Ford; Brian R., eds. Chapman

2007-01-01

One hundred and one mammal species are described that occur in the southern United States. Narrative accounts provide a comprehensive overview of relevant taxonomy, conservation status, distribution, life history, and guidelines for management. Mammal associations within 17 terrestrial and five aquatic communities are presented in the form of habitat relationship...

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

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

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

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...

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lane, Vanessa R; Kilgo, John C

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);more » (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.« less

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.

Predictors for presence and abundance of small mammals in households of villages endemic for commensal rodent plague in Yunnan Province, China

PubMed Central

Yin, Jia-Xiang; Geater, Alan; Chongsuvivatwong, Virasakdi; Dong, Xing-Qi; Du, Chun-Hong; Zhong, You-Hong; McNeil, Edward

2008-01-01

Background Ninety-one rodent plague epidemics have occurred in Lianghe county, Yunnan Province, China, between 1990 and 2006. This study aimed to identify predictors for the presence and abundance of small mammals in households of villages endemic for rodent plague in Lianghe county. Results Rattus flavipectus and Suncus murinus were the two species captured in 110 households. Keeping cats decreased the number of captures of R. flavipectus by one to two thirds and the chance of reported small mammal sightings in houses by 60 to 80%. Food availability was associated with fewer captures. Keeping food in sacks decreased the small mammal captures, especially of S. murinus 4- to 8-fold. Vegetables grown around house and maize grown in the village reduced the captures of S. murinus and R. flavipectus by 73 and 45%, respectively. An outside toilet and garbage piles near the house each reduced R. flavipectus captures by 39 and 37%, respectively, while raising dogs and the presence of communal latrines in the village increased R. flavipectus captures by 76 and 110% but were without detectable effect on small mammal sightings. Location adjacent to other houses increased captures 2-fold but reduced the chance of sightings to about half. In addition, raising ducks increased the chance of sighting small mammals 2.7-fold. Even after adjusting for these variables, households of the Dai had higher captures than those of the Han and other ethnic groups. Conclusion Both species captures were reduced by availability of species-specific foods in the environment, whereas other predictors for capture of the two species differed. Other than the beneficial effect of cats, there were also discrepancies between the effects on small mammal captures and those on sightings. These differences should be considered during the implementation and interpretation of small mammal surveys. PMID:19068139

Differential accumulation of polychlorinated biphenyl congeners in the terrestrial food web of the Kalamazoo River Superfund site, Michigan.

PubMed

Blankenship, Alan L; Zwiernik, Matthew J; Coady, Katherine K; Kay, Denise P; Newsted, John L; Strause, Karl; Park, Cyrus; Bradley, Patrick W; Neigh, Arianne M; Millsap, Stephanie D; Jones, Paul D; Giesy, John P

2005-08-15

A series of field studies was conducted to determine the bioaccumulation of polychlorinated biphenyl (PCB) congeners in the terrestrial food web of the Kalamazoo River flood plain. Samples included colocated soils, native plants likely to be consumed by wildlife, several taxa of terrestrial invertebrates, small mammals, passerine bird eggs, nestlings, and adults, and great horned owl plasma and eggs. Mean concentrations of total PCBs in samples from the former Trowbridge impoundment were 6.5 mg/kg dry weight for soils and 0.023, 0.13, 1.3, 1.3, 1.6, and 8.2 mg/kg wet weight for plants, small herbivorous mammals, depurated earthworms, shrews, great horned owl eggs, and house wren eggs, respectively. Historical data from the Kalamazoo River have reported Aroclor-equivalent total PCB concentrations in the terrestrial food web; however, the degree of environmental weathering of the parent PCB mixtures was unknown. In this study, earthworms and composite samples of coleoptera exhibited PCB congener patterns that were similar to patterns in colocated soils. However, in plants, less chlorinated PCBs (e.g., mono-, di-, tri-, and tetrachlorinated biphenyls) were predominant, and in small mammals, there was a notable enrichment of PCBs 153, 180, 138, 118, and 99. In general, concentrations of PCBs were lower in most biota than in soil from the Kalamazoo River Area of Concern (KRAOC) although there was a modest biomagnification of PCBs from lower trophic level biota to highertrophic levels. As a consequence of environmental weathering of PCBs in the terrestrial food web of the KRAOC, the relative potency of the PCBs (expressed as mg TEQs/kg PCBs) decreased from soil to most biota. While there was a general trend, as expected, in which concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) increased with total PCBs, this relationship was rather poor (R2 = 0.13). Taken together, these data suggest that the differential accumulation of PCB congeners in the

Serologic evidence of the exposure of small mammals to spotted-fever Rickettsia and Rickettsia bellii in Minas Gerais, Brazil.

PubMed

Coelho, Marcella Gonçalves; Ramos, Vanessa do Nascimento; Limongi, Jean Ezequiel; de Lemos, Elba Regina Sampaio; Guterres, Alexandro; da Costa Neto, Sócrates Fraga; Rozental, Tatiana; Bonvicino, Cibele Rodrigues; D'Andrea, Paulo Sérgio; Moraes-Filho, Jonas; Labruna, Marcelo Bahia; Szabó, Matias Pablo Juan

2016-03-31

Sources of pathogenic Rickettsia in wildlife are largely unknown in Brazil. In this work, potential tick vectors and seroreactivity of small mammals against four spotted-fever group Rickettsia (R. rickettsii, R. parkeri, R. amblyommii and R. rhipicephali) and Rickettsia bellii from peri-urban areas of Uberlândia, a major town in Brazil, are described for the first time. Small mammals were captured and blood samples collected. Ticks were collected from the surface of the host and the environment and posteriorly identified. Reactivity of small mammal sera to Rickettsia was tested by indirect immunofluorescence assay (IFA) using crude antigens from five Brazilian Rickettsia isolates. Information was obtained from 416 small mammals (48 Marsupialia and 368 Rodentia). Forty-eight animals were parasitized and two tick species, Ixodes loricatus and Amblyomma dubitatum, were found on several host species, with a few tick-host relationships described for the first time. From the 416 tested sera, 70 reacted to at least one Rickettsia antigen (prevalence of 16.8%) and from these, 19 (27.1%) reacted to two or more antigens. Seroprevalence was higher for marsupials (39.6%) than for rodents (13.8%). Marsupial and Rhipidomys spp. sera reacted mainly (highest seroprevalence and titers) to R. bellii, and that of Necromys lasiurus mainly to R. rickettsii. Although the serologic assays poorly discriminate between closely related spotted-fever group Rickettsia, the observed small mammal seroreactivity suggests the circulation of Rickettsia in the peri-urban area of Uberlândia, albeit at low levels.

Late Cenozoic onset of the latitudinal diversity gradient of North American mammals

NASA Astrophysics Data System (ADS)

Marcot, Jonathan D.; Fox, David L.; Niebuhr, Spencer R.

2016-06-01

The decline of species richness from equator to pole, or latitudinal diversity gradient (LDG), is nearly universal among clades of living organisms, yet whether it was such a pervasive pattern in the geologic past remains uncertain. Here, we calculate the strength of the LDG for terrestrial mammals in North America over the past 65 My, using 27,903 fossil occurrences of Cenozoic terrestrial mammals from western North America downloaded from the Paleobiology Database. Accounting for temporal and spatial variation in sampling, the LDG was substantially weaker than it is today for most of the Cenozoic and the robust modern LDG of North American mammals evolved only over the last 4 My. The strength of the LDG correlates negatively with global temperature, suggesting a role of global climate patterns in the establishment and maintenance of the LDG for North American mammals.

An improved camera trap for amphibians, reptiles, small mammals, and large invertebrates

USGS Publications Warehouse

Hobbs, Michael T.; Brehme, Cheryl S.

2017-01-01

Camera traps are valuable sampling tools commonly used to inventory and monitor wildlife communities but are challenged to reliably sample small animals. We introduce a novel active camera trap system enabling the reliable and efficient use of wildlife cameras for sampling small animals, particularly reptiles, amphibians, small mammals and large invertebrates. It surpasses the detection ability of commonly used passive infrared (PIR) cameras for this application and eliminates problems such as high rates of false triggers and high variability in detection rates among cameras and study locations. Our system, which employs a HALT trigger, is capable of coupling to digital PIR cameras and is designed for detecting small animals traversing small tunnels, narrow trails, small clearings and along walls or drift fencing.

An improved camera trap for amphibians, reptiles, small mammals, and large invertebrates.

PubMed

Hobbs, Michael T; Brehme, Cheryl S

2017-01-01

Camera traps are valuable sampling tools commonly used to inventory and monitor wildlife communities but are challenged to reliably sample small animals. We introduce a novel active camera trap system enabling the reliable and efficient use of wildlife cameras for sampling small animals, particularly reptiles, amphibians, small mammals and large invertebrates. It surpasses the detection ability of commonly used passive infrared (PIR) cameras for this application and eliminates problems such as high rates of false triggers and high variability in detection rates among cameras and study locations. Our system, which employs a HALT trigger, is capable of coupling to digital PIR cameras and is designed for detecting small animals traversing small tunnels, narrow trails, small clearings and along walls or drift fencing.

An improved camera trap for amphibians, reptiles, small mammals, and large invertebrates

PubMed Central

2017-01-01

Camera traps are valuable sampling tools commonly used to inventory and monitor wildlife communities but are challenged to reliably sample small animals. We introduce a novel active camera trap system enabling the reliable and efficient use of wildlife cameras for sampling small animals, particularly reptiles, amphibians, small mammals and large invertebrates. It surpasses the detection ability of commonly used passive infrared (PIR) cameras for this application and eliminates problems such as high rates of false triggers and high variability in detection rates among cameras and study locations. Our system, which employs a HALT trigger, is capable of coupling to digital PIR cameras and is designed for detecting small animals traversing small tunnels, narrow trails, small clearings and along walls or drift fencing. PMID:28981533

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...

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...

Species’ traits help predict small mammal responses to habitat homogenization by an invasive grass

USGS Publications Warehouse

Ceradini, Joseph P.; Chalfoun, Anna D.

2017-01-01

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

Fungi from interior organs of free-living small mammals in Czechoslovakia and Yugoslavia.

PubMed

Hubálek, Z; Rosický, B; Otcenásek, M

1980-01-01

A total of 308 fungi was isolated from interior organs (lungs, spleen, liver) of 529 small mammals belonging to 21 species, 7 families and 3 orders (Insectivora, Chiroptera, Rodentia), some of these being potentially pathogenic to vertebrates (e.g. Aspergillus flavus, A. fumigatus, Geotrichum candidum, Mucor pusillus, Rhizopus arrhizus). In one vole (Microtus arvalis) captured in South Moravia, adiaspiromycosis (Emmonsia crescens) was demonstrated. Comparison of mycoflora of hair and that of interior organs of wild small mammals revealed that out of the total number of isolates the following fungi were represented in a higher proportion from visceral organs than from the hair: Aspergillus (A. amstelodami, A. flavus, A. repens), Aureobasidium (A. pullulans), Candida, Cladosporium (C. herbarum), Cryptococcus, Fusarium, Gliocladium (G. deliquescens), Helminthosporium, Kloeckera, Mucor (M. fragilis, M. hiemalis, M. pusillus), Paecilomyces marquandii, Penicillium (P. purpurogenum), Phoma, Rhizopus arrhizus, Scopulariopsis (S. candida, S. koningii) and Torulopsis.

Community structure and diversity of tropical forest mammals: data from a global camera trap network.

PubMed

Ahumada, Jorge A; Silva, Carlos E F; Gajapersad, Krisna; Hallam, Chris; Hurtado, Johanna; Martin, Emanuel; McWilliam, Alex; Mugerwa, Badru; O'Brien, Tim; Rovero, Francesco; Sheil, Douglas; Spironello, Wilson R; Winarni, Nurul; Andelman, Sandy J

2011-09-27

Terrestrial mammals are a key component of tropical forest communities as indicators of ecosystem health and providers of important ecosystem services. However, there is little quantitative information about how they change with local, regional and global threats. In this paper, the first standardized pantropical forest terrestrial mammal community study, we examine several aspects of terrestrial mammal species and community diversity (species richness, species diversity, evenness, dominance, functional diversity and community structure) at seven sites around the globe using a single standardized camera trapping methodology approach. The sites-located in Uganda, Tanzania, Indonesia, Lao PDR, Suriname, Brazil and Costa Rica-are surrounded by different landscape configurations, from continuous forests to highly fragmented forests. We obtained more than 51 000 images and detected 105 species of mammals with a total sampling effort of 12 687 camera trap days. We find that mammal communities from highly fragmented sites have lower species richness, species diversity, functional diversity and higher dominance when compared with sites in partially fragmented and continuous forest. We emphasize the importance of standardized camera trapping approaches for obtaining baselines for monitoring forest mammal communities so as to adequately understand the effect of global, regional and local threats and appropriately inform conservation actions.

Mammal Inventory of the Mojave Network Parks-Death Valley and Joshua Tree National Parks, Lake Mead National Recreation Area, Manzanar National Historic Site, and Mojave National Preserve

USGS Publications Warehouse

Drost, Charles A.; Hart, Jan

2008-01-01

This report describes the results of a mammal inventory study of National Park Service units in the Mojave Desert Network, including Death Valley National Park, Joshua Tree National Park, Lake Mead National Recreation Area, Manzanar National Historic Site, and Mojave National Preserve. Fieldwork for the inventory focused on small mammals, primarily rodents and bats. Fieldwork for terrestrial small mammals used trapping with Sherman and Tomahawk small- and medium-sized mammal traps, along with visual surveys for diurnal species. The majority of sampling for terrestrial small mammals was carried out in 2002 and 2003. Methods used in field surveys for bats included mist-netting at tanks and other water bodies, along with acoustic surveys using Anabat. Most of the bat survey work was conducted in 2003. Because of extremely dry conditions in the first two survey years (and associated low mammal numbers), we extended field sampling into 2004, following a relatively wet winter. In addition to field sampling, we also reviewed, evaluated, and summarized museum and literature records of mammal species for all of the Park units. We documented a total of 59 mammal species as present at Death Valley National Park, with an additional five species that we consider of probable occurrence. At Joshua Tree, we also documented 50 species, and an additional four 'probable' species. At Lake Mead National Recreation Area, 57 mammal species have been positively documented, with 10 additional probable species. Manzanar National Historic Site had not been previously surveyed. We documented 19 mammal species at Manzanar, with an additional 11 probable species. Mojave National Preserve had not had a comprehensive list previously, either. There are now a total of 50 mammal species documented at Mojave, with three additional probable species. Of these totals, 23 occurrences are new at individual park units (positively documented for the first time), with most of these being at Manzanar

Contaminant Exposure in Terrestrial Vertebrates

EPA Science Inventory

Manuscript is a critical review of the state of the science for quantifying exposures of terrestrial wildlife species to chemical contamination. It describes the unique aspects of birds, mammals, reptiles, amphibians and threatened and endangered species. Fate and transport of ...

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

Sleep alterations in mammals: did aquatic conditions inhibit rapid eye movement sleep?

PubMed

Madan, Vibha; Jha, Sushil K

2012-12-01

Sleep has been studied widely in mammals and to some extent in other vertebrates. Higher vertebrates such as birds and mammals have evolved an inimitable rapid eye movement (REM) sleep state. During REM sleep, postural muscles become atonic and the temperature regulating machinery remains suspended. Although REM sleep is present in almost all the terrestrial mammals, the aquatic mammals have either radically reduced or completely eliminated REM sleep. Further, we found a significant negative correlation between REM sleep and the adaptation of the organism to live on land or in water. The amount of REM sleep is highest in terrestrial mammals, significantly reduced in semi-aquatic mammals and completely absent or negligible in aquatic mammals. The aquatic mammals are obligate swimmers and have to surface at regular intervals for air. Also, these animals live in thermally challenging environments, where the conductive heat loss is approximately ~90 times greater than air. Therefore, they have to be moving most of the time. As an adaptation, they have evolved unihemispheric sleep, during which they can rove as well as rest. A condition that immobilizes muscle activity and suspends the thermoregulatory machinery, as happens during REM sleep, is not suitable for these animals. It is possible that, in accord with Darwin's theory, aquatic mammals might have abolished REM sleep with time. In this review, we discuss the possibility of the intrinsic role of aquatic conditions in the elimination of REM sleep in the aquatic mammals.

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

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...

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.

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.

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

Non-neurogenic SVZ-like niche in dolphins, mammals devoid of olfaction.

PubMed

Parolisi, Roberta; Cozzi, Bruno; Bonfanti, Luca

2017-08-01

Adult neurogenesis has been implicated in brain plasticity and brain repair. In mammals, it is mostly restricted to specific brain regions and specific physiological functions. The function and evolutionary history of mammalian adult neurogenesis has been elusive so far. The largest neurogenic site in mammals (subventricular zone, SVZ) generates neurons destined to populate the olfactory bulb. The SVZ neurogenic activity appears to be related to the dependence of the species on olfaction since it occurs at high rates throughout life in animals strongly dependent on this function for their survival. Indeed, it dramatically decreases in humans, who do not depend so much on it. This study investigates whether the SVZ neurogenic site exists in mammals devoid of olfaction and olfactory brain structures, such as dolphins. Our results demonstate that a small SVZ-like region persists in these aquatic mammals. However, this region seems to have lost its neurogenic capabilities since neonatal stages. In addition, instead of the typical newly generated neuroblasts, some mature neurons were observed in the dolphin SVZ. Since cetaceans evolved from terrestrial ancestors, non-neurogenic SVZ may indicate extinction of adult neurogenesis in the absence of olfactory function, with the retention of an SVZ-like anatomical region either vestigial or of still unknown role.

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 ...

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...

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) ...

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

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

Morphological and molecular characterization and phylogenetic relationships of a new species of trypanosome in Tapirus terrestris (lowland tapir), Trypanosoma terrestris sp. nov., from Atlantic Rainforest of southeastern Brazi.

PubMed

Acosta, Igor da Cunha Lima; da Costa, Andrea Pereira; Nunes, Pablo Henrique; Gondim, Maria Fernanda Naegeli; Gatti, Andressa; Rossi, João Luiz; Gennari, Solange Maria; Marcili, Arlei

2013-12-11

The Lowland tapir (Tapirus terrestris) is the largest Brazilian mammal and despite being distributed in various Brazilian biomes, it is seriously endangered in the Atlantic Rainforest. These hosts were never evaluated for the presence of Trypanosoma parasites. The Lowland tapirs were captured in the Brazilian southeastern Atlantic Rainforest, Espírito Santo state. Trypanosomes were isolated by hemoculture, and the molecular phylogeny based on small subunit rDNA (SSU rDNA) and glycosomal-3-phosphate dehydrogenase (gGAPDH) gene sequences and the ultrastructural features seen via light microscopy and scanning and transmission electron microscopy are described. Phylogenetic trees using combined SSU rDNA and gGAPDH data sets clustered the trypanosomes of Lowland tapirs, which were highly divergent from other trypanosome species. The phylogenetic position and morphological discontinuities, mainly in epimastigote culture forms, made it possible to classify the trypanosomes from Lowland tapirs as a separate species. The isolated trypanosomes from Tapirus terrestris are a new species, Trypanosoma terrestris sp. n., and were positioned in a new Trypanosoma clade, named T. terrestris clade.

Morphological and molecular characterization and phylogenetic relationships of a new species of trypanosome in Tapirus terrestris (lowland tapir), Trypanosoma terrestris sp. nov., from Atlantic Rainforest of southeastern Brazi

PubMed Central

2013-01-01

Background The Lowland tapir (Tapirus terrestris) is the largest Brazilian mammal and despite being distributed in various Brazilian biomes, it is seriously endangered in the Atlantic Rainforest. These hosts were never evaluated for the presence of Trypanosoma parasites. Methods The Lowland tapirs were captured in the Brazilian southeastern Atlantic Rainforest, Espírito Santo state. Trypanosomes were isolated by hemoculture, and the molecular phylogeny based on small subunit rDNA (SSU rDNA) and glycosomal-3-phosphate dehydrogenase (gGAPDH) gene sequences and the ultrastructural features seen via light microscopy and scanning and transmission electron microscopy are described. Results Phylogenetic trees using combined SSU rDNA and gGAPDH data sets clustered the trypanosomes of Lowland tapirs, which were highly divergent from other trypanosome species. The phylogenetic position and morphological discontinuities, mainly in epimastigote culture forms, made it possible to classify the trypanosomes from Lowland tapirs as a separate species. Conclusions The isolated trypanosomes from Tapirus terrestris are a new species, Trypanosoma terrestris sp. n., and were positioned in a new Trypanosoma clade, named T. terrestris clade. PMID:24330660

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...

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

PubMed

Ceradini, Joseph P; Chalfoun, Anna D

2017-07-01

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

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

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. Copyright © 2015 Elsevier Inc. All rights reserved.

Ecological surveillance of small mammals at Firing Points 10 and 60, Gyeonggi Province, Republic of Korea, 2001-2005.

PubMed

O'Guinn, Monica L; Klein, Terry A; Lee, John S; Kim, Heung-Chul; Baek, Luck-Ju; Chong, Sung-Tae; Turell, Michael J; Burkett, Douglas A; Schuster, Anthony; Lee, In-Yong; Yi, Suk-Hee; Sames, William J; Song, Ki-Joon; Song, Jin-Won

2008-12-01

Throughout Korea, small mammals are hosts to a number of disease-causing agents that pose a health threat to U.S. and Korean military forces while they conduct field-training exercises. A seasonal rodent-borne disease surveillance program was established at two firing points (FP), FP-10, and FP-60, and conducted over five years from 2001 through 2005 in response to hantavirus cases among U.S. soldiers. The ecology of these sites consisted primarily of tall grasses associated with semi-permanent and temporary water sources (drainage ditches and a small stream) and dry-land agriculture farming. Eight species of rodents and one species of insectivore were collected, including Apodemus agrarius, Micromys minutus, Mus musculus, Rattus norvegicus, Tscherskia triton, Microtus fortis, Myodes regulus, and Crocidura lasiura. The striped field mouse, A. agrarius, (primary reservoir for Hantaan virus, the causative agent of Korean hemorrhagic fever), was the most frequently collected, representing 90.6% of the 1,288 small mammals captured at both sites. Reported herein are the ecological parameters, seasonal population densities, and seasonal population characteristics associated with small mammals collected at two military training sites in the Republic of Korea.

Assessment of the role of small mammals in the transmission cycle of tegumentary leishmaniasis and first report of natural infection with Leishmania braziliensis in two sigmodontines in northeastern Argentina.

PubMed

Fernández, María S; Fraschina, Jimena; Acardi, Soraya; Liotta, Domingo J; Lestani, Eduardo; Giuliani, Magalí; Busch, María; Salomón, O Daniel

2018-02-01

To contribute to the knowledge of the role of small mammals in the transmission cycle of tegumentary leishmaniasis caused by Leishmania braziliensis, we studied the small mammal community and its temporal and spatial association with phlebotominae, as well as small mammal infection by Leishmania spp. by PCR-RFLP analyses in an endemic area of northeastern Argentina. Ten small mammal samplings were conducted (2007-2009, 7506 Sherman trap nights and 422 cage trap nights). In two of these samplings, 16 capture stations each one consisting of a CDC light trap to capture phlebotominae, two to four Sherman traps and two cage traps were placed. We found co-occurrence of phlebotominae and small mammal captures in four stations, which were all the stations with small mammal captures and yielded 97% (2295 specimens, including 21 gravid females) of the total phlebotominae captures, suggesting that small mammals may provide a potential source of blood for phlebotominae females. One Didelphis albiventris and two Rattus rattus were associated with high captures of Nyssomyia whitmani, vector of L. braziliensis in the study area. The PCR-RFLP analyses confirm the presence of L. braziliensis in two sigmodontine small mammals (Akodon sp. and Euryoryzomys russatus) for the first time in Argentina, to our knowledge.

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...

Do Bird Friendly® Coffee Criteria Benefit Mammals? Assessment of Mammal Diversity in Chiapas, Mexico

PubMed Central

Caudill, S. Amanda; Rice, Robert A.

2016-01-01

Biodiversity-friendly coffee certifications offer a viable way to protect wildlife habitat while providing a financial incentive to farmers. Most studies related to these certifications focus on avian habitat requirements and it is not known whether these standards also apply to other wildlife, such as mammals, that inhabit the coffee landscapes. We assessed the non-volant mammalian fauna and their associated habitat requirements in 23 sites representing forest, Bird Friendly® shade, conventional shade, and sun coffee habitats. We used Sherman trap-grids to measure small mammal abundance and richness, while camera traps were set for medium-sized and large mammals. We detected 17 species of mammals, representing 11 families. This preliminary study indicates that coffee farms in this region provide an important refuge for mammalian wildlife. Mammal species density ranked significantly higher in Bird Friendly® coffee sites than other coffee habitats, although there was no significant difference for species richness (using Chao2 estimator) among the habitat types. No significant difference was found in small mammal abundance among the habitat types. We found a higher species density of medium and large mammals in sites with larger, more mature shade trees associated with, but not required by Bird Friendly® certification standards. However, lower strata vegetation (5 cm to 1 m tall), the only vegetation parameter found to increase abundance and density for small mammals, is not specified in the Bird Friendly® standards. Our findings suggest that although the standards devised for avian habitat do benefit mammals, further study is needed on the requirements specific for mammals that could be included to enhance the coffee habitat for mammals that inhabit these coffee landscapes. PMID:27880773

Do Bird Friendly® Coffee Criteria Benefit Mammals? Assessment of Mammal Diversity in Chiapas, Mexico.

PubMed

Caudill, S Amanda; Rice, Robert A

2016-01-01

Biodiversity-friendly coffee certifications offer a viable way to protect wildlife habitat while providing a financial incentive to farmers. Most studies related to these certifications focus on avian habitat requirements and it is not known whether these standards also apply to other wildlife, such as mammals, that inhabit the coffee landscapes. We assessed the non-volant mammalian fauna and their associated habitat requirements in 23 sites representing forest, Bird Friendly® shade, conventional shade, and sun coffee habitats. We used Sherman trap-grids to measure small mammal abundance and richness, while camera traps were set for medium-sized and large mammals. We detected 17 species of mammals, representing 11 families. This preliminary study indicates that coffee farms in this region provide an important refuge for mammalian wildlife. Mammal species density ranked significantly higher in Bird Friendly® coffee sites than other coffee habitats, although there was no significant difference for species richness (using Chao2 estimator) among the habitat types. No significant difference was found in small mammal abundance among the habitat types. We found a higher species density of medium and large mammals in sites with larger, more mature shade trees associated with, but not required by Bird Friendly® certification standards. However, lower strata vegetation (5 cm to 1 m tall), the only vegetation parameter found to increase abundance and density for small mammals, is not specified in the Bird Friendly® standards. Our findings suggest that although the standards devised for avian habitat do benefit mammals, further study is needed on the requirements specific for mammals that could be included to enhance the coffee habitat for mammals that inhabit these coffee landscapes.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 thatmore » 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.« less

Small-Mammal Data on Early and Middle Holocene Climates and Biotic Communities in the Bonneville Basin, USA

NASA Astrophysics Data System (ADS)

Schmitt, Dave N.; Madsen, David B.; Lupo, Karen D.

2002-11-01

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.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Talmage, S.S.; 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 comparativemore » 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.« less

Anthropogenic water sources and the effects on Sonoran Desert small mammal communities

PubMed Central

Switalski, Aaron B.

2017-01-01

Anthropogenic water sources (AWS) are developed water sources used as a management tool for desert wildlife species. Studies documenting the effects of AWS are often focused on game species; whereas, the effects on non-target wildlife are less understood. We used live trapping techniques to investigate rodent abundance, biomass, and diversity metrics near AWS and paired control sites; we sampled vegetation to determine rodent-habitat associations in the Sauceda Mountains of the Sonoran Desert in Arizona. A total of 370 individual mammals representing three genera and eight species were captured in 4,800 trap nights from winter 2011 to spring 2012. A multi-response permutation procedure was used to identify differences in small mammal community abundance and biomass by season and treatment. Rodent abundance, biomass, and richness were greater at AWS compared to control sites. Patterns of abundance and biomass were driven by the desert pocket mouse (Chaetodipus penicillatus) which was the most common capture and two times more numerous at AWS compared to controls. Vegetation characteristics, explored using principal components analysis, were similar between AWS and controls. Two species that prefer vegetation structure, Bailey’s pocket mouse (C. baileyi) and white-throated woodrat (Neotoma albigula), had greater abundances and biomass near AWS and were associated with habitat having high cactus density. Although small mammals do not drink free-water, perhaps higher abundances of some species of desert rodents at AWS could be related to artificial structure associated with construction or other resources. Compared to the 30-year average of precipitation for the area, the period of our study occurred during a dry winter. During dry periods, perhaps AWS provide resources to rodents related to moisture. PMID:29134147

Anthropogenic water sources and the effects on Sonoran Desert small mammal communities.

PubMed

Switalski, Aaron B; Bateman, Heather L

2017-01-01

Anthropogenic water sources (AWS) are developed water sources used as a management tool for desert wildlife species. Studies documenting the effects of AWS are often focused on game species; whereas, the effects on non-target wildlife are less understood. We used live trapping techniques to investigate rodent abundance, biomass, and diversity metrics near AWS and paired control sites; we sampled vegetation to determine rodent-habitat associations in the Sauceda Mountains of the Sonoran Desert in Arizona. A total of 370 individual mammals representing three genera and eight species were captured in 4,800 trap nights from winter 2011 to spring 2012. A multi-response permutation procedure was used to identify differences in small mammal community abundance and biomass by season and treatment. Rodent abundance, biomass, and richness were greater at AWS compared to control sites. Patterns of abundance and biomass were driven by the desert pocket mouse ( Chaetodipus penicillatus ) which was the most common capture and two times more numerous at AWS compared to controls. Vegetation characteristics, explored using principal components analysis, were similar between AWS and controls. Two species that prefer vegetation structure, Bailey's pocket mouse ( C. baileyi ) and white-throated woodrat ( Neotoma albigula) , had greater abundances and biomass near AWS and were associated with habitat having high cactus density. Although small mammals do not drink free-water, perhaps higher abundances of some species of desert rodents at AWS could be related to artificial structure associated with construction or other resources. Compared to the 30-year average of precipitation for the area, the period of our study occurred during a dry winter. During dry periods, perhaps AWS provide resources to rodents related to moisture.

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

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...

Climate change and body size trends in aquatic and terrestrial endotherms: Does habitat matter?

PubMed

Naya, Daniel E; Naya, Hugo; Cook, Joseph

2017-01-01

Several studies have claimed that reduction in body size comprises a nearly universal response to global warming; however, doubts about the validity of this pattern for endothermic species have been raised recently. Accordingly, we assessed temporal changes in body mass for 27 bird and 17 mammal species, to evaluate if a reduction in body size during the 20th century is a widespread phenomenon among endothermic vertebrates. In addition, we tested if there are differences in the temporal change in size between birds and mammals, aquatic and terrestrial species, and the first and second half of the 20th century. Overall, six species increased their body mass, 21 species showed no significant changes in size, and 17 species decreased their body mass during the 20th century. Temporal changes in body mass were similar for birds and mammals, but strongly differ between aquatic and terrestrial species: while most of the aquatic species increased or did not change in body mass, most terrestrial species decreased in size. In addition, we found that, at least in terrestrial birds, the mean value of the correlation between body mass and year of collection differs between the first half and the second half of the 20th century, being close to zero for the former period but negative for the later one. To our knowledge, this is the first study showing that temporal changes in body mass differ between aquatic and terrestrial species in both mammals and birds.

Climate change and body size trends in aquatic and terrestrial endotherms: Does habitat matter?

PubMed Central

Naya, Hugo; Cook, Joseph

2017-01-01

Several studies have claimed that reduction in body size comprises a nearly universal response to global warming; however, doubts about the validity of this pattern for endothermic species have been raised recently. Accordingly, we assessed temporal changes in body mass for 27 bird and 17 mammal species, to evaluate if a reduction in body size during the 20th century is a widespread phenomenon among endothermic vertebrates. In addition, we tested if there are differences in the temporal change in size between birds and mammals, aquatic and terrestrial species, and the first and second half of the 20th century. Overall, six species increased their body mass, 21 species showed no significant changes in size, and 17 species decreased their body mass during the 20th century. Temporal changes in body mass were similar for birds and mammals, but strongly differ between aquatic and terrestrial species: while most of the aquatic species increased or did not change in body mass, most terrestrial species decreased in size. In addition, we found that, at least in terrestrial birds, the mean value of the correlation between body mass and year of collection differs between the first half and the second half of the 20th century, being close to zero for the former period but negative for the later one. To our knowledge, this is the first study showing that temporal changes in body mass differ between aquatic and terrestrial species in both mammals and birds. PMID:28813491

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 (

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 smallmore » 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

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.

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...

Seasonal and environmental determinants of leptospirosis and scrub typhus in small mammals captured at a U.S. military training site (Dagmar North), Republic of Korea, 2001-2004.

PubMed

Payne, Kevin S; Klein, Terry A; Otto, Jean L; Kim, Heung-Chul; Chong, Sung-Tae; Ha, Si Jung; Gu, Se Hun; Jeong, Ji Hae; Baek, Luck Ju; Song, Jin-Won

2009-10-01

This study sought to identify seasonal and environmental determinants of scrub typhus, murine typhus, and leptospirosis in small mammals trapped at Dagmar North training area, Gyeonggi Province, South Korea. Small mammals received titer assays to the aforementioned diseases. Logistic regression analyses were conducted to determine whether associations existed between risk of small-mammal infection and independent variables such as season of capture, habitat, small-mammal species, and sex. Murine typhus was not detected among the animals assayed. Risk of scrub typhus infection was associated with season, habitat, and small-mammal species. Risk of leptospirosis infection was associated with season and habitat. These findings indicate determinants of infection exist for scrub typhus and leptospirosis at this training site. This information can be used for developing appropriate preventive medicine plans and coordinating troop activity during periods of reduced exposure decreasing the likelihood of disease transmission to humans.

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

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

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.

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.

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.

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.

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.

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...

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.

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

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.

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...

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.

List of recent land mammals from Mexico, 2014

USGS Publications Warehouse

Ramirez-Pulido, Jose; Gonzalez-Ruiz, Noe; Gardner, Alfred L.; Arroyo-Cabrales, Joaquin

2014-01-01

We provide an updated list of the Recent land mammals of Mexico and include information on the taxonomy of certain species, and where appropriate, the endemic and threatened status of all species listed. Several taxonomic and nomenclatural changes have been made since publication of the last list of the Mexican terrestrial mammalian fauna. Within the period from 2005 to present, there have been at least 209 changes concerning the nomenclature of this fauna; these we evaluated in this paper. The land mammals of Mexico comprise 168 genera, 496 species, and 881 subspecies.

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.

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 (...

Osmoregulation in marine mammals

NASA Technical Reports Server (NTRS)

Ortiz, R. M.

2001-01-01

Osmoregulation in marine mammals has been investigated for over a century; however, a review of recent advances in our understanding of water and electrolyte balance and of renal function in marine mammals is warranted. The following topics are discussed: (i) kidney structure and urine concentrating ability, (ii) sources of water, (iii) the effects of feeding, fasting and diving, (iv) the renal responses to infusions of varying salinity and (v) hormonal regulation. The kidneys of pinnipeds and cetaceans are reniculate in structure, unlike those of terrestrial mammals (except bears), but this difference does not confer any greater concentrating ability. Pinnipeds, cetaceans, manatees and sea otters can concentrate their urine above the concentration of sea water, but only pinnipeds and otters have been shown to produce urine concentrations of Na+ and Cl- that are similar to those in sea water. This could afford them the capacity to drink sea water and not lose fresh water. However, with few exceptions, drinking is not a common behavior in pinnipeds and cetaceans. Water balance is maintained in these animals via metabolic and dietary water, while incidental ingestion and dietary salt may help maintain electrolyte homeostasis. Unlike most other aquatic mammals, sea otters commonly drink sea water and manatees frequently drink fresh water. Among the various taxonomic groups of marine mammals, the sensitivity of the renin-angiotensin-aldosterone system appears to be influenced by the availability of Na+. The antidiuretic role of vasopressin remains inconclusive in marine mammals, while the natriuretic function of atrial natriuretic peptide has yet to be examined. Ideas on the direction of future studies are presented.

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...

Influence of fire on mammals in eastern oak forests

Treesearch

Patrick D. Keyser; W. Mark Ford

2006-01-01

With the exception of small mammals, little research has been conducted in eastern oak forests on the influence of fire on mammals. Several studies have documented little or no change inrelative abundance or community measures for non-volant small mammals in eastern oak (Quercus spp.) forests following fires despite reductions in leaf litter, small woody debris, and...

77 FR 30996 - Taking and Importing Marine Mammals: Taking Marine Mammals Incidental to Navy's Research...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-24

... mammals were seen using shore- based survey during the pre- and post-event surveys. No marine mammals were... for both the pre and post surveys. The survey vessel was the NS-50 small range craft and it was used for pre- and post-event monitoring. The NS-50 vessel crew consisted of a Craft master, marine mammal...

Small mammals taphonomy and environmental evolution during Late Pleistocene-Holocene in Monte Desert: The evidence of Gruta del Indio (central west Argentina)

NASA Astrophysics Data System (ADS)

Fernández, Fernando J.; Pardiñas, Ulyses F. J.

2018-07-01

Very few excavated sequences in southern South America provide an approximation to the environmental evolution covering the segment Late Pleistocene-Holocene. Here we present the taphonomic analysis and paleoenvironmental reconstruction based on the small mammal remains retrieved from the archaeological and paleontological site Gruta del Indio (Mendoza Province, Argentina). Radiocarbon dates situate the small mammal deposits studied within the Late Pleistocene and Holocene. Thus, these assemblages provide a record for inferring environmental evolution in the middle basin of Atuel River during the last ∼31 ky BP. Taphonomic analysis revealed that most of small mammal remains were incorporated by a little destructive nocturnal owl. Recorded species include mainly cricetid and caviomorph rodents and a single marsupial. While Pleistocene assemblages have not exclusive species, the specific richness increases towards the Holocene probably linked with the climatic variability related to ENSO. In overall, the recorded small mammals suggest environmental stability during the Late Pleistocene-Holocene, mostly associated with Monte Desert conditions. Conversely, the pollen sequence studied from Gruta del Indio was interpreted as indicator of a deep environmental change during the Pleistocene-Holocene transition, when the Patagonian steppe was replaced by Monte Desert. Potential biases linked with these kinds of proxies are discussed.

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

Scale effects between body size and limb design in quadrupedal mammals.

PubMed

Kilbourne, Brandon M; Hoffman, Louwrens C

2013-01-01

Recently the metabolic cost of swinging the limbs has been found to be much greater than previously thought, raising the possibility that limb rotational inertia influences the energetics of locomotion. Larger mammals have a lower mass-specific cost of transport than smaller mammals. The scaling of the mass-specific cost of transport is partly explained by decreasing stride frequency with increasing body size; however, it is unknown if limb rotational inertia also influences the mass-specific cost of transport. Limb length and inertial properties--limb mass, center of mass (COM) position, moment of inertia, radius of gyration, and natural frequency--were measured in 44 species of terrestrial mammals, spanning eight taxonomic orders. Limb length increases disproportionately with body mass via positive allometry (length ∝ body mass(0.40)); the positive allometry of limb length may help explain the scaling of the metabolic cost of transport. When scaled against body mass, forelimb inertial properties, apart from mass, scale with positive allometry. Fore- and hindlimb mass scale according to geometric similarity (limb mass ∝ body mass(1.0)), as do the remaining hindlimb inertial properties. The positive allometry of limb length is largely the result of absolute differences in limb inertial properties between mammalian subgroups. Though likely detrimental to locomotor costs in large mammals, scale effects in limb inertial properties appear to be concomitant with scale effects in sensorimotor control and locomotor ability in terrestrial mammals. Across mammals, the forelimb's potential for angular acceleration scales according to geometric similarity, whereas the hindlimb's potential for angular acceleration scales with positive allometry.

Scale Effects between Body Size and Limb Design in Quadrupedal Mammals

PubMed Central

Kilbourne, Brandon M.; Hoffman, Louwrens C.

2013-01-01

Recently the metabolic cost of swinging the limbs has been found to be much greater than previously thought, raising the possibility that limb rotational inertia influences the energetics of locomotion. Larger mammals have a lower mass-specific cost of transport than smaller mammals. The scaling of the mass-specific cost of transport is partly explained by decreasing stride frequency with increasing body size; however, it is unknown if limb rotational inertia also influences the mass-specific cost of transport. Limb length and inertial properties – limb mass, center of mass (COM) position, moment of inertia, radius of gyration, and natural frequency – were measured in 44 species of terrestrial mammals, spanning eight taxonomic orders. Limb length increases disproportionately with body mass via positive allometry (length ∝ body mass0.40); the positive allometry of limb length may help explain the scaling of the metabolic cost of transport. When scaled against body mass, forelimb inertial properties, apart from mass, scale with positive allometry. Fore- and hindlimb mass scale according to geometric similarity (limb mass ∝ body mass1.0), as do the remaining hindlimb inertial properties. The positive allometry of limb length is largely the result of absolute differences in limb inertial properties between mammalian subgroups. Though likely detrimental to locomotor costs in large mammals, scale effects in limb inertial properties appear to be concomitant with scale effects in sensorimotor control and locomotor ability in terrestrial mammals. Across mammals, the forelimb's potential for angular acceleration scales according to geometric similarity, whereas the hindlimb's potential for angular acceleration scales with positive allometry. PMID:24260117

Responses of large mammals to climate change.

PubMed

Hetem, Robyn S; Fuller, Andrea; Maloney, Shane K; Mitchell, Duncan

2014-01-01

Most large terrestrial mammals, including the charismatic species so important for ecotourism, do not have the luxury of rapid micro-evolution or sufficient range shifts as strategies for adjusting to climate change. The rate of climate change is too fast for genetic adaptation to occur in mammals with longevities of decades, typical of large mammals, and landscape fragmentation and population by humans too widespread to allow spontaneous range shifts of large mammals, leaving only the expression of latent phenotypic plasticity to counter effects of climate change. The expression of phenotypic plasticity includes anatomical variation within the same species, changes in phenology, and employment of intrinsic physiological and behavioral capacity that can buffer an animal against the effects of climate change. Whether that buffer will be realized is unknown, because little is known about the efficacy of the expression of plasticity, particularly for large mammals. Future research in climate change biology requires measurement of physiological characteristics of many identified free-living individual animals for long periods, probably decades, to allow us to detect whether expression of phenotypic plasticity will be sufficient to cope with climate change.

Responses of large mammals to climate change

PubMed Central

Hetem, Robyn S; Fuller, Andrea; Maloney, Shane K; Mitchell, Duncan

2014-01-01

Most large terrestrial mammals, including the charismatic species so important for ecotourism, do not have the luxury of rapid micro-evolution or sufficient range shifts as strategies for adjusting to climate change. The rate of climate change is too fast for genetic adaptation to occur in mammals with longevities of decades, typical of large mammals, and landscape fragmentation and population by humans too widespread to allow spontaneous range shifts of large mammals, leaving only the expression of latent phenotypic plasticity to counter effects of climate change. The expression of phenotypic plasticity includes anatomical variation within the same species, changes in phenology, and employment of intrinsic physiological and behavioral capacity that can buffer an animal against the effects of climate change. Whether that buffer will be realized is unknown, because little is known about the efficacy of the expression of plasticity, particularly for large mammals. Future research in climate change biology requires measurement of physiological characteristics of many identified free-living individual animals for long periods, probably decades, to allow us to detect whether expression of phenotypic plasticity will be sufficient to cope with climate change. PMID:27583293

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.

Seasonal thermoregulatory responses in mammals.

PubMed

Lovegrove, Barry G

2005-05-01

This study examined the proportional seasonal winter adjustments of total and mass-specific basal power (watts and watts g-1, respectively), thermal conductance (watts g-1 degrees C-1), non-shivering thermogenesis capacity (ratio of NST/basal power), body temperature ( degrees C), and body mass (g) of mammals. The responses are best summarized for three different body size classes; small mammals (<100 g), intermediate-sized mammals (0.1-10 kg), and large mammals (>10 kg). The principal adjustments of the small mammals center on energy conservation, especially the Dehnel Effect, the winter reduction in body size of as much as 50%, accompanied by reductions in mass-specific basal power. On average, these reductions reduce the total basal power approximately in direct proportion to the mass reductions. Reductions in mass-specific basal power are matched by concomitant reductions in conductance to maintain the setpoint body temperature during winter. The overall thermoregulatory adjustments in small mammals serve to (a) lower overall winter power consumption, (b) maintain the setpoint body temperature, and (c) lower the lower critical limit of thermoneutrality and hence thermoregulatory costs. In intermediate-size mammals, the seasonal response is centered more on increasing thermogenic capacity by increasing basal power and NST capacity, accompanied by predictable and large reductions in conductance. The Dehnel effect is negligible. Very large mammals undergo the largest reductions in total and mass-specific basal power and conductance. However, there are too few data to resolve whether the reductions in total basal power can be attributed to the Dehnel effect, because the moderate decreases in body mass may also be caused by nutritional stress. Apart from the seasonal changes in basal power, these observations are consistent with the predictions of Heldmaier's seasonal acclimatization model.

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-...

Endocrine Function In Naturally Long-Living Small Mammals

PubMed Central

Buffenstein, Rochelle; Pinto, Mario

2015-01-01

The complex, highly integrative endocrine system regulates all aspects of somatic maintenance and reproduction and has been widely implicated as an important determinant of longevity in short-lived traditional model organisms of aging research. Genetic or experimental manipulation of hormone profiles in mice has been proven to definitively alter longevity. These hormonally induced lifespan extension mechanisms may not necessarily be relevant to humans and other long-lived organisms that naturally show successful slow aging. Long-lived species may have evolved novel anti-aging defenses germane to naturally retarding the aging process. Here we examine the available endocrine data associated with the vitamin D, insulin, grlucocorticoid and thyroid endocrine systems of naturally long-living small mammals. Generally, long-living rodents and bats maintain tightly regulated lower basal levels of these key pleiotropic hormones than shorter-lived rodents. Similarities with genetically manipulated suggest that evolutionarily wellconserved hormonal mechanisms are integrally involved in lifespan determination. PMID:18674586

Pre-harvest (1994-1995) Conditions of the Missouri Ozark Forest Ecosystem Project Small Mammal Communities

Treesearch

Debby K. Fantz; Rochelle B. Renken

1997-01-01

We conducted a capture-recapture study on northeast-facing slopes to determine the pre-treatment landscape-scale effect of even- and uneven-aged silvicultural treatments upon the species composition, species richness, and relative abundance of small mammals on Missouri Ozark Forest Ecosystem Project (MOFEP) sites. Similarity indices of species composition between sites...

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...

New Fossil Evidence on the Sister-Group of Mammals and Early Mesozoic Faunal Distributions

NASA Astrophysics Data System (ADS)

Shubin, Neil H.; Crompton, A. W.; Sues, Hans-Dieter; Olsen, Paul E.

1991-03-01

Newly discovered remains of highly advanced mammal-like reptiles (Cynodontia: Tritheledontidae) from the Early Jurassic of Nova Scotia, Canada, have revealed that aspects of the characteristic mammalian occlusal pattern are primitive. Mammals and tritheledontids share an homologous pattern of occlusion that is not seen in other cynodonts. The new tritheledontids represent the first definite record of this family from North America. The extreme similarity of North American and African tritheledontids supports the hypothesis that the global distribution of terrestrial tetrapods was homogeneous in the Early Jurassic. This Early Jurassic cosmopolitanism represents the continuation of a trend toward increased global homogeneity among terrestrial tetrapod communities that began in the late Paleozoic.

A new fossil mammal assemblage from the southern Chilean Andes: implications for geology, geochronology, and tectonics

NASA Astrophysics Data System (ADS)

Flynn, John J.; Novacek, Michael J.; Dodson, Holly E.; Frassinetti, Daniel; McKenna, Malcolm C.; Norell, Mark A.; Sears, Karen E.; Swisher, Carl C.; Wyss, André R.

2002-07-01

A diverse (36 taxa), new fossil terrestrial mammal assemblage has been recovered from the Santacrucian South American Land Mammal 'Age' (SALMA; latest Early Miocene) in the southern Andes of Chile. This is the westernmost high latitude mammal fauna known in South America and the first in a string of new mammal assemblages discovered in Chile after a lapse of nearly a century. The terrestrial mammal-bearing sequence conformably overlies a marine section of Late Oligocene to Early Miocene age. The combined marine-terrestrial sequence, as well as a locality with fossil whales and bracketing basalts, bear significantly on theories regarding the extent of the late Tertiary Patagonian epicontinental seaway and the onset of later Cenozoic phases of uplift in the southern Andes. Uplift in this region likely began by Santacrucian SALMA (˜16-17.5 Ma) time, but it remains uncertain whether this occurred in two phases (Pehuenchic and Quechuic) or one. These discoveries substantiate propositions of sharp geologic contrasts north and south of the Lago General Carrera/Lago Buenos Aires area (Magellanes basin to the south and Río Mayo embayment to the north). Minimum estimates of uplift rate are approximately 0.05-0.07 mm/yr (but as high as 0.22 mm/yr), comparable to or slightly lower than those from other parts of the Andes (e.g. Bolivia). The timing and location of uplift may be correlated with major plate tectonic events associated with the Chile Margin Triple Junction.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Landeen, D.S.

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,more » 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.« less

A phenology of the evolution of endothermy in birds and mammals.

PubMed

Lovegrove, Barry G

2017-05-01

Recent palaeontological data and novel physiological hypotheses now allow a timescaled reconstruction of the evolution of endothermy in birds and mammals. A three-phase iterative model describing how endothermy evolved from Permian ectothermic ancestors is presented. In Phase One I propose that the elevation of endothermy - increased metabolism and body temperature (T b ) - complemented large-body-size homeothermy during the Permian and Triassic in response to the fitness benefits of enhanced embryo development (parental care) and the activity demands of conquering dry land. I propose that Phase Two commenced in the Late Triassic and Jurassic and was marked by extreme body-size miniaturization, the evolution of enhanced body insulation (fur and feathers), increased brain size, thermoregulatory control, and increased ecomorphological diversity. I suggest that Phase Three occurred during the Cretaceous and Cenozoic and involved endothermic pulses associated with the evolution of muscle-powered flapping flight in birds, terrestrial cursoriality in mammals, and climate adaptation in response to Late Cenozoic cooling in both birds and mammals. Although the triphasic model argues for an iterative evolution of endothermy in pulses throughout the Mesozoic and Cenozoic, it is also argued that endothermy was potentially abandoned at any time that a bird or mammal did not rely upon its thermal benefits for parental care or breeding success. The abandonment would have taken the form of either hibernation or daily torpor as observed in extant endotherms. Thus torpor and hibernation are argued to be as ancient as the origins of endothermy itself, a plesiomorphic characteristic observed today in many small birds and mammals. © 2016 Cambridge Philosophical Society.

Axial allometry in a neutrally buoyant environment: effects of the terrestrial-aquatic transition on vertebral scaling.

PubMed

Jones, K E; Pierce, S E

2016-03-01

Ecological diversification into new environments presents new mechanical challenges for locomotion. An extreme example of this is the transition from a terrestrial to an aquatic lifestyle. Here, we examine the implications of life in a neutrally buoyant environment on adaptations of the axial skeleton to evolutionary increases in body size. On land, mammals must use their thoracolumbar vertebral column for body support against gravity and thus exhibit increasing stabilization of the trunk as body size increases. Conversely, in water, the role of the axial skeleton in body support is reduced, and, in aquatic mammals, the vertebral column functions primarily in locomotion. Therefore, we hypothesize that the allometric stabilization associated with increasing body size in terrestrial mammals will be minimized in secondarily aquatic mammals. We test this by comparing the scaling exponent (slope) of vertebral measures from 57 terrestrial species (23 felids, 34 bovids) to 23 semi-aquatic species (pinnipeds), using phylogenetically corrected regressions. Terrestrial taxa meet predictions of allometric stabilization, with posterior vertebral column (lumbar region) shortening, increased vertebral height compared to width, and shorter, more disc-shaped centra. In contrast, pinniped vertebral proportions (e.g. length, width, height) scale with isometry, and in some cases, centra even become more spool-shaped with increasing size, suggesting increased flexibility. Our results demonstrate that evolution of a secondarily aquatic lifestyle has modified the mechanical constraints associated with evolutionary increases in body size, relative to terrestrial taxa. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

An example of population-level risk assessments for small mammals using individual-based population models.

PubMed

Schmitt, Walter; Auteri, Domenica; Bastiansen, Finn; Ebeling, Markus; Liu, Chun; Luttik, Robert; Mastitsky, Sergey; Nacci, Diane; Topping, Chris; Wang, Magnus

2016-01-01

This article presents a case study demonstrating the application of 3 individual-based, spatially explicit population models (IBMs, also known as agent-based models) in ecological risk assessments to predict long-term effects of a pesticide to populations of small mammals. The 3 IBMs each used a hypothetical fungicide (FungicideX) in different scenarios: spraying in cereals (common vole, Microtus arvalis), spraying in orchards (field vole, Microtus agrestis), and cereal seed treatment (wood mouse, Apodemus sylvaticus). Each scenario used existing model landscapes, which differed greatly in size and structural complexity. The toxicological profile of FungicideX was defined so that the deterministic long-term first tier risk assessment would result in high risk to small mammals, thus providing the opportunity to use the IBMs for risk assessment refinement (i.e., higher tier risk assessment). Despite differing internal model design and scenarios, results indicated in all 3 cases low population sensitivity unless FungicideX was applied at very high (×10) rates. Recovery from local population impacts was generally fast. Only when patch extinctions occured in simulations of intentionally high acute toxic effects, recovery periods, then determined by recolonization, were of any concern. Conclusions include recommendations for the most important input considerations, including the selection of exposure levels, duration of simulations, statistically robust number of replicates, and endpoints to report. However, further investigation and agreement are needed to develop recommendations for landscape attributes such as size, structure, and crop rotation to define appropriate regulatory risk assessment scenarios. Overall, the application of IBMs provides multiple advantages to higher tier ecological risk assessments for small mammals, including consistent and transparent direct links to specific protection goals, and the consideration of more realistic scenarios. © 2015 SETAC.

Small mammal use of native warm-season and non-native cool-season grass forage fields

USGS Publications Warehouse

Ryan L Klimstra,; Christopher E Moorman,; Converse, Sarah J.; Royle, J. Andrew; Craig A Harper,

2015-01-01

Recent emphasis has been put on establishing native warm-season grasses for forage production because it is thought native warm-season grasses provide higher quality wildlife habitat than do non-native cool-season grasses. However, it is not clear whether native warm-season grass fields provide better resources for small mammals than currently are available in non-native cool-season grass forage production fields. We developed a hierarchical spatially explicit capture-recapture model to compare abundance of hispid cotton rats (Sigmodon hispidus), white-footed mice (Peromyscus leucopus), and house mice (Mus musculus) among 4 hayed non-native cool-season grass fields, 4 hayed native warm-season grass fields, and 4 native warm-season grass-forb ("wildlife") fields managed for wildlife during 2 summer trapping periods in 2009 and 2010 of the western piedmont of North Carolina, USA. Cotton rat abundance estimates were greater in wildlife fields than in native warm-season grass and non-native cool-season grass fields and greater in native warm-season grass fields than in non-native cool-season grass fields. Abundances of white-footed mouse and house mouse populations were lower in wildlife fields than in native warm-season grass and non-native cool-season grass fields, but the abundances were not different between the native warm-season grass and non-native cool-season grass fields. Lack of cover following haying in non-native cool-season grass and native warm-season grass fields likely was the key factor limiting small mammal abundance, especially cotton rats, in forage fields. Retention of vegetation structure in managed forage production systems, either by alternately resting cool-season and warm-season grass forage fields or by leaving unharvested field borders, should provide refugia for small mammals during haying events.

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...

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.

Biomechanics and energetics in aquatic and semiaquatic mammals: platypus to whale.

PubMed

Fish, F E

2000-01-01

A variety of mammalian lineages have secondarily invaded the water. To locomote and thermoregulate in the aqueous medium, mammals developed a range of morphological, physiological, and behavioral adaptations. A distinct difference in the suite of adaptations, which affects energetics, is apparent between semiaquatic and fully aquatic mammals. Semiaquatic mammals swim by paddling, which is inefficient compared to the use of oscillating hydrofoils of aquatic mammals. Semiaquatic mammals swim at the water surface and experience a greater resistive force augmented by wave drag than submerged aquatic mammals. A dense, nonwettable fur insulates semiaquatic mammals, whereas aquatic mammals use a layer of blubber. The fur, while providing insulation and positive buoyancy, incurs a high energy demand for maintenance and limits diving depth. Blubber contours the body to reduce drag, is an energy reserve, and suffers no loss in buoyancy with depth. Despite the high energetic costs of a semiaquatic existence, these animals represent modern analogs of evolutionary intermediates between ancestral terrestrial mammals and their fully aquatic descendants. It is these intermediate animals that indicate which potential selection factors and mechanical constraints may have directed the evolution of more derived aquatic forms.

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. Copyright © 2013 Elsevier B.V. All rights reserved.

Antimicrobial resistance in generic Escherichia coli isolates from wild small mammals living in swine farm, residential, landfill, and natural environments in southern Ontario, Canada.

PubMed

Allen, Samantha E; Boerlin, Patrick; Janecko, Nicol; Lumsden, John S; Barker, Ian K; Pearl, David L; Reid-Smith, Richard J; Jardine, Claire

2011-02-01

To assess the impacts of different types of human activity on the development of resistant bacteria in the feces of wild small mammals, we compared the prevalences and patterns of antimicrobial resistance and resistance genes in generic Escherichia coli and Salmonella enterica isolates from fecal samples collected from wild small mammals living in four environments: swine farms, residential areas, landfills, and natural habitats. Resistance to antimicrobials was observed in E. coli isolates from animals in all environments: 25/52 (48%) animals trapped at swine farms, 6/69 (9%) animals trapped in residential areas, 3/20 (15%) animals trapped at landfills, and 1/22 (5%) animals trapped in natural habitats. Animals trapped on farms were significantly more likely to carry E. coli isolates with resistance to tetracycline, ampicillin, sulfisoxazole, and streptomycin than animals trapped in residential areas. The resistance genes sul2, aadA, and tet(A) were significantly more likely to be detected in E. coli isolates from animals trapped on farms than from those trapped in residential areas. Three S. enterica serotypes (Give, Typhimurium, and Newport) were recovered from the feces of 4/302 (1%) wild small mammals. All Salmonella isolates were pansusceptible. Our results show that swine farm origin is significantly associated with the presence of resistant bacteria and resistance genes in wild small mammals in southern Ontario, Canada. However, resistant fecal bacteria were found in small mammals living in all environments studied, indicating that environmental exposure to antimicrobials, antimicrobial residues, resistant bacteria, or resistance genes is widespread.

Communication masking in marine mammals: A review and research strategy.

PubMed

Erbe, Christine; Reichmuth, Colleen; Cunningham, Kane; Lucke, Klaus; Dooling, Robert

2016-02-15

Underwater noise, whether of natural or anthropogenic origin, has the ability to interfere with the way in which marine mammals receive acoustic signals (i.e., for communication, social interaction, foraging, navigation, etc.). This phenomenon, termed auditory masking, has been well studied in humans and terrestrial vertebrates (in particular birds), but less so in marine mammals. Anthropogenic underwater noise seems to be increasing in parts of the world's oceans and concerns about associated bioacoustic effects, including masking, are growing. In this article, we review our understanding of masking in marine mammals, summarise data on marine mammal hearing as they relate to masking (including audiograms, critical ratios, critical bandwidths, and auditory integration times), discuss masking release processes of receivers (including comodulation masking release and spatial release from masking) and anti-masking strategies of signalers (e.g. Lombard effect), and set a research framework for improved assessment of potential masking in marine mammals. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Vector biodiversity did not associate with tick-borne pathogen prevalence in small mammal communities in northern and central California.

PubMed

Foley, Janet; Piovia-Scott, Jonah

2014-04-01

Vector and host abundance affect infection transmission rates, prevalence, and persistence in communities. Biological diversity in hosts and vectors may provide "rescue" hosts which buffer against pathogen extinction and "dilution" hosts which reduce the force of infection in communities. Anaplasma phagocytophilum is a tick-transmitted zoonotic pathogen that circulates in small mammal and tick communities characterized by varying levels of biological diversity. We examined the prevalence of A. phagocytophilum in Ixodes spp. ticks in 11 communities in northern and central California. A total of 1020 ticks of 8 species was evaluated. Five percent of ticks (5 species) were PCR-positive, with the highest prevalence (6-7%) in I. pacificus and I. ochotonae. In most species, adults had a higher prevalence than nymphs or larvae. PCR prevalence varied between 0% and 40% across sites; the infection probability in ticks increased with infestation load and prevalence in small mammals, but not tick species richness, diversity, evenness, or small mammal species richness. No particular tick species was likely to "rescue" infection in the community; rather the risk of A. phagocytophilum infection is related to exposure to particular tick species and life stages, and overall tick abundance. Copyright © 2014 Elsevier GmbH. All rights reserved.

The comparison of species longevity and size evolution in fossilized dinosaurs vs. fossilized mammals

NASA Astrophysics Data System (ADS)

Baeza, E.; Srinath, A.; Hernandez, A.; Heim, N.; Payne, J.

2016-12-01

For over 200 million years, two animal groups have been competing for dominance over Earth: the reptiles, (in this case, dinosaurs), and the mammals. At the beginning of the Triassic, mammals were small, rat-like creatures that were dwarfed by the dinosaurs. Dinosaurs progressively continued to grow larger throughout the Jurassic and Cretaceous periods, thus outweighing and outliving the current mammals. But at the end of the Cretaceous, the K-T mass extinction occurred, and that wiped out the dinosaurs from the face of the Earth. After the disappearance of dinosaurs, mammals started to grow larger to fill the niches that the dinosaurs left open. With this evolution in mammals, would they be able to match or even beat the dinosaur's previous records? To judge that, we need to utilize two significant factors to help judge our answer. The two factors that set them apart were body mass and longevity. Documenting the body mass shows us how much the animal weighed compared to other species. The heaviest animal in our data set weighed 77 tons. The other factor is longevity, which indicates how long a certain species has existed on a geologic time scale. The longest living animal species in our data set lived for over 20 million years. With all the data we have analyzed, we have conducted research on this subject to find out how terrestrial mammals contrasted dinosaurs in the terms of body mass and species longevity. Our research brought us to the conclusion that mammals could not overtake the body mass and longevity of dinosaurs. Although mammals came pretty close to overlapping the dinosaurs' body masses, they were just below them marginally. We had a similar pattern in longevity, where we found out that heavier animals tended to have longer longevity, therefore the dinosaurs came out on top. Additionally, we did another contrast between Mesozoic and Cenozoic mammals, where Cenozoic mammals were larger, but both had similar longevities.

Mammal population regulation, keystone processes and ecosystem dynamics.

PubMed Central

Sinclair, A R E

2003-01-01

The theory of regulation in animal populations is fundamental to understanding the dynamics of populations, the causes of mortality and how natural selection shapes the life history of species. In mammals, the great range in body size allows us to see how allometric relationships affect the mode of regulation. Resource limitation is the fundamental cause of regulation. Top-down limitation through predators is determined by four factors: (i). body size; (ii). the diversity of predators and prey in the system; (iii). whether prey are resident or migratory; and (iv). the presence of alternative prey for predators. Body size in mammals has two important consequences. First, mammals, particularly large species, can act as keystones that determine the diversity of an ecosystem. I show how keystone processes can, in principle, be measured using the example of the wildebeest in the Serengeti ecosystem. Second, mammals act as ecological landscapers by altering vegetation succession. Mammals alter physical structure, ecological function and species diversity in most terrestrial biomes. In general, there is a close interaction between allometry, population regulation, life history and ecosystem dynamics. These relationships are relevant to applied aspects of conservation and pest management. PMID:14561329

Keystone effects of an alien top-predator stem extinctions of native mammals

PubMed Central

Letnic, Mike; Koch, Freya; Gordon, Chris; Crowther, Mathew S.; Dickman, Christopher R.

2009-01-01

Alien predators can have catastrophic effects on ecosystems and are thought to be much more harmful to biodiversity than their native counterparts. However, trophic cascade theory and the mesopredator release hypothesis predict that the removal of top predators will result in the reorganization of trophic webs and loss of biodiversity. Using field data collected throughout arid Australia, we provide evidence that removal of an alien top-predator, the dingo, has cascading effects through lower trophic levels. Dingo removal was linked to increased activity of herbivores and an invasive mesopredator, the red fox (Vulpes vulpes), and to the loss of grass cover and native species of small mammals. Using species distribution data, we predict that reintroducing or maintaining dingo populations would produce a net benefit for the conservation of threatened native mammals across greater than 2.42 × 106 km2 of Australia. Our study provides evidence that an alien top predator can assume a keystone role and be beneficial for biodiversity conservation, and also that mammalian carnivores more generally can generate strong trophic cascades in terrestrial ecosystems. PMID:19535372

Permeability of hair to cadmium, copper and lead in five species of terrestrial mammals and implications in biomonitoring.

PubMed

Rendón-Lugo, A N; Santiago, P; Puente-Lee, I; León-Paniagua, L

2017-11-18

The capacity of mammal hair to absorb toxic metals and its utility in biomonitoring has been broadly studied. Though these metal-binding properties has generally been attributed to the sulphur contained in cysteine, an amino acid that forms part of keratin, there are not many experimental studies that analyze the role of sulphur in the external deposition of potentially toxic metallic elements in order to better understand the potential of hair in biomonitoring and generate better tools for differentiating between internal and external deposition of contaminants. In this study, an experimental analysis is carried out using a scanning electron microscope on hairs of five terrestrial mammal species (Peromyscus furvus, P. maniculatus, Glossophaga soricina, Artibeus jamaicensis and Marmosa mexicana) treated with cadmium, copper and lead salts. We quantified absorbed metals as well as natural elements of the hair by energy dispersive X-ray spectroscopy (EDS) to analyze using simple statistics the role of sulphur in the absorption Cd, Cu and Pb. Given the lack of studies comparing the mechanisms of deposition of metal elements among different orders of Class Mammalia, external morphology was considered to be an important factor in the deposition of metallic particles of Cd, Cu and Pb. Bat species (Glossophaga soricina, Artibeus jamaicensis) showed a high concentration of particles in their scales, however, no between-species differences in metal absorption were observed, and during the exogenous deposition metal particles do not permeate the medulla. These results suggest that the sulphur in hair itself cannot bind metals to hair cuticle and that hair absorption capacity depends on a variety of factors such as aspects of hair morphology.

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...

The enzootic life-cycle of Borrelia burgdorferi (sensu lato) and tick-borne rickettsiae: an epidemiological study on wild-living small mammals and their ticks from Saxony, Germany.

PubMed

Obiegala, Anna; Król, Nina; Oltersdorf, Carolin; Nader, Julian; Pfeffer, Martin

2017-03-13

Borrelia burgdorferi (sensu lato) and rickettsiae of the spotted fever group are zoonotic tick-borne pathogens. While small mammals are confirmed reservoirs for certain Borrelia spp., little is known about the reservoirs for tick-borne rickettsiae. Between 2012 and 2014, ticks were collected from the vegetation and small mammals which were trapped in Saxony, Germany. DNA extracted from ticks and the small mammals' skin was analyzed for the presence of Rickettsia spp. and B. burgdorferi (s.l.) by qPCR targeting the gltA and p41 genes, respectively. Partial sequencing of the rickettsial ompB gene and an MLST of B. burgdorferi (s.l.) were conducted for species determination. In total, 673 small mammals belonging to eight species (Apodemus agrarius, n = 7; A. flavicollis, n = 214; Microtus arvalis, n = 8; Microtus agrestis, n = 1; Mustela nivalis, n = 2; Myodes glareolus, n = 435; Sorex araneus, n = 5; and Talpa europaea, n = 1) were collected and examined. In total, 916 questing ticks belonging to three species (Ixodes ricinus, n = 741; Dermacentor reticulatus, n = 174; and I. trianguliceps, n = 1) were collected. Of these, 474 ticks were further investigated. The prevalence for Rickettsia spp. and B. burgdorferi (s.l.) in the investigated small mammals was 25.3 and 31.2%, respectively. The chance of encountering Rickettsia spp. in M. glareolus was seven times higher for specimens infested with D. reticulatus than for those which were free of D. reticulatus (OR: 7.0; 95% CI: 3.3-14.7; P < 0.001). In total, 11.4% of questing I. ricinus and 70.5% of D. reticulatus were positive for Rickettsia spp. DNA of B. burgdorferi (s.l.) was detected only in I. ricinus (5.5%). Sequence analysis revealed 9 R. helvetica, 5 R. raoultii, and 1 R. felis obtained from 15 small mammal samples. Small mammals may serve as reservoirs for Rickettsia spp. and B. burgdorferi (s.l.). While the prevalence for Rickettsia spp. in M. glareolus is most

[Gamasid mites of small mammals in the semi-desert territories of the Saratov Trans-Volga region].

PubMed

Porshakov, A M; Yakovlev, S A; Kurnyaeva, A D

2017-01-01

The paper contains the data on the species composition and comparative analysis of gamaside mites, parasitizing on small mammals in the semi-desert territories of Saratov trans-Volga region. On the basis of the results of investigations conducted in the Aleksandrovo-Gaisky District in 2008-2013, 18 species of gamaside mites (9 genusus, 5 families) have been recorded. Nine species of maaside mites, which were not found in semi-desert zone earlier were revealed, includiding Hypoaspis (Stratiolaelaps) miles Berlese, 1882, H. (Geolaelaps) heselhausi Oudemans, 1912, H. (G.) lubrica Oudemans et Voigts, 1604, G. et. R. Canestrini, 1881, Haemogamasus citelli Bregetova et Nelzina, 1952, Hirstionyssus eusoricis Bregetova, 1956, Hi. ellobii Bregetova, 1653; five of these species are new for the territory of Saratov Province. As a result of the study of semi-desert zone of Saratov trans-Volga region and taking into account literary data, parasitic fauna of small mammals of Aleksandrovo-Gaisky District was expanded up to 21 species, and of Saratov Province, up to 44 species of gamasid mites.

Isotopic and anatomical evidence of an herbivorous diet in the Early Tertiary giant bird Gastornis. Implications for the structure of Paleocene terrestrial ecosystems

NASA Astrophysics Data System (ADS)

Angst, D.; Lécuyer, C.; Amiot, R.; Buffetaut, E.; Fourel, F.; Martineau, F.; Legendre, S.; Abourachid, A.; Herrel, A.

2014-04-01

The mode of life of the early Tertiary giant bird Gastornis has long been a matter of controversy. Although it has often been reconstructed as an apex predator feeding on small mammals, according to other interpretations, it was in fact a large herbivore. To determine the diet of this bird, we analyze here the carbon isotope composition of the bone apatite from Gastornis and contemporaneous herbivorous mammals. Based on 13C-enrichment measured between carbonate and diet of carnivorous and herbivorous modern birds, the carbonate δ13C values of Gastornis bone remains, recovered from four Paleocene and Eocene French localities, indicate that this bird fed on plants. This is confirmed by a morphofunctional study showing that the reconstructed jaw musculature of Gastornis was similar to that of living herbivorous birds and unlike that of carnivorous forms. The herbivorous Gastornis was the largest terrestrial tetrapod in the Paleocene biota of Europe, unlike the situation in North America and Asia, where Gastornis is first recorded in the early Eocene, and the largest Paleocene animals were herbivorous mammals. The structure of the Paleocene terrestrial ecosystems of Europe may have been similar to that of some large islands, notably Madagascar, prior to the arrival of humans.

Convergent evolution of the genomes of marine mammals

USGS Publications Warehouse

Foote, Andrew D.; Liu, Yue; Thomas, Gregg W.C.; Vinař, Tomáš; Alföldi, Jessica; Deng, Jixin; Dugan, Shannon; van Elk, Cornelis E.; Hunter, Margaret; Joshi, Vandita; Khan, Ziad; Kovar, Christie; Lee, Sandra L.; Lindblad-Toh, Kerstin; Mancia, Annalaura; Nielsen, Rasmus; Qin, Xiang; Qu, Jiaxin; Raney, Brian J.; Vijay, Nagarjun; Wolf, Jochen B. W.; Hahn, Matthew W.; Muzny, Donna M.; Worley, Kim C.; Gilbert, M. Thomas P.; Gibbs, Richard A.

2015-01-01

Marine mammals from different mammalian orders share several phenotypic traits adapted to the aquatic environment and therefore represent a classic example of convergent evolution. To investigate convergent evolution at the genomic level, we sequenced and performed de novo assembly of the genomes of three species of marine mammals (the killer whale, walrus and manatee) from three mammalian orders that share independently evolved phenotypic adaptations to a marine existence. Our comparative genomic analyses found that convergent amino acid substitutions were widespread throughout the genome and that a subset of these substitutions were in genes evolving under positive selection and putatively associated with a marine phenotype. However, we found higher levels of convergent amino acid substitutions in a control set of terrestrial sister taxa to the marine mammals. Our results suggest that, whereas convergent molecular evolution is relatively common, adaptive molecular convergence linked to phenotypic convergence is comparatively rare.

Convergent evolution of the genomes of marine mammals

PubMed Central

Foote, Andrew D.; Liu, Yue; Thomas, Gregg W.C.; Vinař, Tomáš; Alföldi, Jessica; Deng, Jixin; Dugan, Shannon; van Elk, Cornelis E.; Hunter, Margaret E.; Joshi, Vandita; Khan, Ziad; Kovar, Christie; Lee, Sandra L.; Lindblad-Toh, Kerstin; Mancia, Annalaura; Nielsen, Rasmus; Qin, Xiang; Qu, Jiaxin; Raney, Brian J.; Vijay, Nagarjun; Wolf, Jochen B. W.; Hahn, Matthew W.; Muzny, Donna M.; Worley, Kim C.; Gilbert, M. Thomas P.; Gibbs, Richard A.

2015-01-01

Marine mammals from different mammalian orders share several phenotypic traits adapted to the aquatic environment and are therefore a classic example of convergent evolution. To investigate convergent evolution at the genomic level, we sequenced and de novo assembled the genomes of three species of marine mammals (the killer whale, walrus and manatee) from three mammalian orders that share independently evolved phenotypic adaptations to a marine existence. Our comparative genomic analyses found that convergent amino acid substitutions were widespread throughout the genome, and that a subset were in genes evolving under positive selection and putatively associated with a marine phenotype. However, we found higher levels of convergent amino acid substitutions in a control set of terrestrial sister taxa to the marine mammals. Our results suggest that while convergent molecular evolution is relatively common, adaptive molecular convergence linked to phenotypic convergence is comparatively rare. PMID:25621460

RADIATION DOSE ASSESSMENT FOR THE BIOTA OF TERRESTRIAL ECOSYSTEMS IN THE SHORELINE ZONE OF THE CHERNOBYL NUCLEAR POWER PLANT COOLING POND

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farfan, E.; Jannik, T.

2011-10-01

Radiation exposure of the biota in the shoreline area of the Chernobyl Nuclear Power Plant Cooling Pond was assessed to evaluate radiological consequences from the decommissioning of the Cooling Pond. The article addresses studies of radioactive contamination of the terrestrial faunal complex and radionuclide concentration ratios in bodies of small birds, small mammals, amphibians, and reptiles living in the area. The data were used to calculate doses to biota using the ERICA Tool software. Doses from {sup 90}Sr and {sup 137}Cs were calculated using the default parameters of the ERICA Tool and were shown to be consistent with biota dosesmore » calculated from the field data. However, the ERICA dose calculations for plutonium isotopes were much higher (2-5 times for small mammals and 10-14 times for birds) than the doses calculated using the experimental data. Currently, the total doses for the terrestrial biota do not exceed maximum recommended levels. However, if the Cooling Pond is allowed to drawdown naturally and the contaminants of the bottom sediments are exposed and enter the biological cycle, the calculated doses to biota may exceed the maximum recommended values. The study is important in establishing the current exposure conditions such that a baseline exists from which changes can be documented following the lowering of the reservoir water. Additionally, the study provided useful radioecological data on biota concentration ratios for some species that are poorly represented in the literature.« less

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...

Faunal analysis of chigger mites (Acari: Prostigmata) on small mammals in Yunnan province, southwest China.

PubMed

Peng, Pei-Ying; Guo, Xian-Guo; Ren, Tian-Guang; Song, Wen-Yu

2015-08-01

This paper studied the species diversity and fauna distribution of chigger mites on small mammals in Yunnan province, southwest Yunnan. In total, 120,138 individuals of chigger mites were collected from 13,760 individual small mammals, and these mites were identified as comprising two families, 26 genera, and 274 species. Of the five zoogeographical subregions, the mite species diversity in subregions I and II was higher than that in subregions III, IV, and V. Four mite species (Leptotrombidium scutellare, Leptotrombidium sinicum, Leptotrombidium deliense, and Helenicula simena) were the most dominant species in the whole province. Several vector species of chigger mites co-existed in Yunnan, and L. deliense (a main vector of scrub typhus in China) was mainly distributed in subregions IV and V with lower latitude and average altitude whereas L. scutellare (also a main vector in China) was mainly distributed in subregions I, II, and III with higher latitude and average altitude. Some geographically widely distributed mite species were also the mites with wide host ranges and low host specificity. The dominant mite species and their clustering tendency in the dendrogram of hierarchical clustering analysis were highly in accordance with the zoogeographical divisions. The species diversity of chigger mites showed a parabolic tendency from the low altitude (<500 m) to the high altitude (>3,500 m) along the vertical gradients and reached the highest value in the middle altitude regions in 2,000-2,500 m. The highest species diversity of the mites and their small mammal hosts happened in the regions around the Hengduan Mountains, which is a hotspot of biodiversity in Asia continent. The host and its sample size, geographical scope, landscape, topography, and some other factors comprehensively influence the species diversity and faunal distribution of chigger mites. A systematic field investigation with a wide geographical scope and large host sample is strongly recommended

Long-term data from a small mammal community reveal loss of diversity and potential effects of local climate change.

PubMed

Santoro, Simone; Sanchez-Suarez, Cristina; Rouco, Carlos; Palomo, L Javier; Fernández, M Carmen; Kufner, Maura B; Moreno, Sacramento

2017-10-01

Climate change affects distribution and persistence of species. However, forecasting species' responses to these changes requires long-term data series that are often lacking in ecological studies. We used 15 years of small mammal trapping data collected between 1978 and 2015 in 3 areas at Doñana National Park (southwest Spain) to (i) describe changes in species composition and (ii) test the association between local climate conditions and size of small mammal populations. Overall, 5 species were captured: wood mouse Apodemus sylvaticus , algerian mouse Mus spretus , greater white-toothed shrew Crocidura russula , garden dormouse Eliomys quercinus , and black rat Rattus rattus . The temporal pattern in the proportion of captures of each species suggests that the small mammal diversity declined with time. Although the larger species (e.g., E. quercinus ), better adapted to colder climate, have disappeared from our trapping records, M. spretus , a small species inhabiting southwest Europe and the Mediterranean coast of Africa, currently is almost the only trapped species. We used 2-level hierarchical models to separate changes in abundance from changes in probability of capture using records of A. sylvaticus in all 3 areas and of M. spretus in 1. We found that heavy rainfall and low temperatures were positively related to abundance of A. sylvaticus , and that the number of extremely hot days was negatively related to abundance of M. spretus . Despite other mechanisms are likely to be involved, our findings support the importance of climate for the distribution and persistence of these species and raise conservation concerns about potential cascading effects in the Doñana ecosystem.

Leishmania (Viannia) braziliensis infection in wild small mammals in ecotourism area of Brazil

PubMed Central

Tonelli, Gabriel Barbosa; Tanure, Aline; Rego, Felipe Dutra; Carvalho, Gustavo Mayr de Lima; Stumpp, Rodolfo; Ássimos, Gabriela Ribeiro; Campos, Aldenise Martins; Lima, Ana Cristina Viana Mariano da Rocha; Gontijo, Célia Maria Ferreira

2017-01-01

Leishmaniases are parasitic diseases transmitted to mammalian hosts by sand fly vectors (Diptera: Psychodidae). Despite the increasing occurrence of visceral and cutaneous leishmaniasis cases in urban centers, their transmission still occur primarily in wild environments and may be associated with professional activities and recreation, such as ecotourism. The Reserva Particular do Patrimônio Natural Santuário do Caraça (RPPNSC) is one of the largest ecotourism attractions in the State of Minas Gerais, Brazil, and comprises an area of environmental preservation with 11,233 hectares presenting a transitional vegetation between Cerrado and Atlantic Forest. The present study describes the abundance of small mammals in RPPNSC, the isolation and identification of Leishmania in five wild animals. Small mammals were bimonthly trapped along 6 trails within the RPPNSC with 10 Tomahawk traps each. Two trails were located in peridomiciliary areas near tourist lodging facilities, and four trails were located at sites visited by tourists in forest areas. The most prevalent species were Akodon cursor, Cerradomys subflavus and Oligoryzomys nigripes. Six isolates of Leishmania were obtained from these animals and identified as Leishmania braziliensis through HSP70-PCR RFLP method. Leishmania spp. DNA was detected by kDNA-PCR method and isolated by biphasic culture. Studies point to some of the captured species as potential wild reservoirs of Leishmania, suggesting they may be involved in the transmission cycle in these wild environments. PMID:29284049

Leishmania (Viannia) braziliensis infection in wild small mammals in ecotourism area of Brazil.

PubMed

Tonelli, Gabriel Barbosa; Tanure, Aline; Rego, Felipe Dutra; Carvalho, Gustavo Mayr de Lima; Stumpp, Rodolfo; Ássimos, Gabriela Ribeiro; Campos, Aldenise Martins; Lima, Ana Cristina Viana Mariano da Rocha; Gontijo, Célia Maria Ferreira; Paz, Gustavo Fontes; Andrade Filho, José Dilermando

2017-01-01

Leishmaniases are parasitic diseases transmitted to mammalian hosts by sand fly vectors (Diptera: Psychodidae). Despite the increasing occurrence of visceral and cutaneous leishmaniasis cases in urban centers, their transmission still occur primarily in wild environments and may be associated with professional activities and recreation, such as ecotourism. The Reserva Particular do Patrimônio Natural Santuário do Caraça (RPPNSC) is one of the largest ecotourism attractions in the State of Minas Gerais, Brazil, and comprises an area of environmental preservation with 11,233 hectares presenting a transitional vegetation between Cerrado and Atlantic Forest. The present study describes the abundance of small mammals in RPPNSC, the isolation and identification of Leishmania in five wild animals. Small mammals were bimonthly trapped along 6 trails within the RPPNSC with 10 Tomahawk traps each. Two trails were located in peridomiciliary areas near tourist lodging facilities, and four trails were located at sites visited by tourists in forest areas. The most prevalent species were Akodon cursor, Cerradomys subflavus and Oligoryzomys nigripes. Six isolates of Leishmania were obtained from these animals and identified as Leishmania braziliensis through HSP70-PCR RFLP method. Leishmania spp. DNA was detected by kDNA-PCR method and isolated by biphasic culture. Studies point to some of the captured species as potential wild reservoirs of Leishmania, suggesting they may be involved in the transmission cycle in these wild environments.

Exercise at depth alters bradycardia and incidence of cardiac anomalies in deep-diving marine mammals.

PubMed

Williams, Terrie M; Fuiman, Lee A; Kendall, Traci; Berry, Patrick; Richter, Beau; Noren, Shawn R; Thometz, Nicole; Shattock, Michael J; Farrell, Edward; Stamper, Andy M; Davis, Randall W

2015-01-16

Unlike their terrestrial ancestors, marine mammals routinely confront extreme physiological and physical challenges while breath-holding and pursuing prey at depth. To determine how cetaceans and pinnipeds accomplish deep-sea chases, we deployed animal-borne instruments that recorded high-resolution electrocardiograms, behaviour and flipper accelerations of bottlenose dolphins (Tursiops truncatus) and Weddell seals (Leptonychotes weddellii) diving from the surface to >200 m. Here we report that both exercise and depth alter the bradycardia associated with the dive response, with the greatest impacts at depths inducing lung collapse. Unexpectedly, cardiac arrhythmias occurred in >73% of deep, aerobic dives, which we attribute to the interplay between sympathetic and parasympathetic drivers for exercise and diving, respectively. Such marked cardiac variability alters the common view of a stereotypic 'dive reflex' in diving mammals. It also suggests the persistence of ancestral terrestrial traits in cardiac function that may help explain the unique sensitivity of some deep-diving marine mammals to anthropogenic disturbances.

The evolution of endothermy in Cenozoic mammals: a plesiomorphic-apomorphic continuum.

PubMed

Lovegrove, Barry Gordon

2012-02-01

The evolution of endothermy in birds and mammals was one of the most important events in the evolution of the vertebrates. Past tests of hypotheses on the evolution of endothermy in mammals have relied largely on analyses of the relationship between basal and maximum metabolic rate, and artificial selection experiments. I argue that components of existing hypotheses, as well as new hypotheses, can be tested using an alternative macrophysiological modeling approach by examining the development of endothermy during the Cenozoic. Recent mammals display a 10°C range in body temperature which is sufficiently large to identify the selective forces that have driven the development of endothermy from a plesiomorphic (ancestral) Cretaceous or Jurassic condition. A model is presented (the Plesiomorphic-Apomorphic Endothermy Model, PAE Model) which proposes that heterothermy, i.e. bouts of normothermy (constant body temperature) interspersed with adaptive heterothermy (e.g. daily torpor and/or hibernation), was the ancestral condition from which apomorphic (derived), rigid homeothermy evolved. All terrestrial mammal lineages are examined for existing data to test the model, as well as for missing data that could be used to test the model. With the exception of Scandentia and Dermoptera, about which little is known, all mammalian orders that include small-sized mammals (<500 g), have species which are heterothermic and display characteristics of endothermy which fall somewhere along a plesiomorphic-apomorphic continuum. Orders which do not have heterothermic representatives (Cetartiodactyla, Perissodactyla, Pholidota, and Lagomorpha) are comprised of medium- to large-sized mammals that have either lost the capacity for heterothermy, or in which heterothermy has yet to be measured. Mammalian heterothermy seems to be plesiomorphic and probably evolved once in the mammalian lineage. Several categories of endothermy are identified (protoendothermy, plesioendothermy, apoendothermy

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

Right place, wrong species: a 20-year review of rabies virus cross species transmission among terrestrial mammals in the United States.

PubMed

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

2014-01-01

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. 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. 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. 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 rabies virus variants.

Mapping of the distribution of Trypanosoma cruzi infection among small wild mammals in a conservation unit and its surroundings (Northeast-Brazil).

PubMed

Xavier, S C C; Vaz, V C; D'Andrea, P S; Herrera, L; Emperaire, L; Alves, J R; Fernandes, O; Ferreira, L F; Jansen, A M

2007-06-01

Maps are a useful tool that permits correlation of landscapes with hotspots of parasite transmission. Here, they were used as a tool for geovisualization to evaluate variables involved in the transmission of Trypanosoma cruzi among small wild mammals in an area endemic for Chagas disease, the "Serra da Capivara" National Park (PARNA) and its surroundings in Piauí State, Northeast Brazil. The implementation of a Geographical Information System (GIS) allowed the observation that a previously noted aggregated distribution of Triatoma sordida and Triatoma brasiliensis, T. cruzi prevalence and infection pattern of small wild mammals was directly or indirectly influenced by the local relief and human action. Small mammalian species diversity was higher in mesic refugia inside the park and in its buffer zone and lower in the disturbed area by anthropic activities. Didelphis albiventris was more abundant in the areas affected by human action. Thrichomys laurentius demonstrated to be an eclectic species and a competent reservoir of T. cruzi, being infected in all study areas. Small wild mammals infected with the TCII genotype of T. cruzi were localized only in the buffer zone of PARNA while TCI infected specimens were found in both areas, inside the PARNA and its buffer zone. The impact of biodiversity loss on the transmission cycle of T. cruzi in the wild environment was discussed.

Geometric factors influencing the diet of vertebrate predators in marine and terrestrial environments

PubMed Central

Carbone, Chris; Codron, Daryl; Scofield, Conrad; Clauss, Marcus; Bielby, Jon; Enquist, Brian

2014-01-01

Predator–prey relationships are vital to ecosystem function and there is a need for greater predictive understanding of these interactions. We develop a geometric foraging model predicting minimum prey size scaling in marine and terrestrial vertebrate predators taking into account habitat dimensionality and biological traits. Our model predicts positive predator–prey size relationships on land but negative relationships in the sea. To test the model, we compiled data on diets of 794 predators (mammals, snakes, sharks and rays). Consistent with predictions, both terrestrial endotherm and ectotherm predators have significantly positive predator–prey size relationships. Marine predators, however, exhibit greater variation. Some of the largest predators specialise on small invertebrates while others are large vertebrate specialists. Prey–predator mass ratios were generally higher for ectothermic than endothermic predators, although dietary patterns were similar. Model-based simulations of predator–prey relationships were consistent with observed relationships, suggesting that our approach provides insights into both trends and diversity in predator–prey interactions. PMID:25265992

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

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...

Skeletal injuries in small mammals: a multispecies assessment of prevalence and location

USGS Publications Warehouse

Stephens, Ryan B.; Burke, Christopher B.; Woodman, Neal; Poland, Lily B.; Rowe, Rebecca J.

2018-01-01

Wild mammals are known to survive injuries that result in skeletal abnormalities. Quantifying and comparing skeletal injuries among species can provide insight into the factors that cause skeletal injuries and enable survival following an injury. We documented the prevalence and location of structural bone abnormalities in a community of 7 small mammal species inhabiting the White Mountains of New Hampshire. These species differ in locomotion type and levels of intraspecific aggression. Overall, the majority of injuries were to the ribs or caudal vertebrae. Incidence of skeletal injuries was highest in older animals, indicating that injuries accumulate over a lifetime. Compared to species with ambulatory locomotion, those with more specialized (semi-fossorial, saltatorial, and scansorial) locomotion exhibited fewer skeletal abnormalities in the arms and legs, which we hypothesize is a result of a lesser ability to survive limb injuries. Patterns of skeletal injuries in shrews (Soricidae) were consistent with intraspecific aggression, particularly in males, whereas skeletal injuries in rodents (Rodentia) were more likely accidental or resulting from interactions with predators. Our results demonstrate that both the incidence and pattern of skeletal injuries vary by species and suggest that the ability of an individual to survive a specific skeletal injury depends on its severity and location as well as the locomotor mode of the species involved.

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.

Predicted Shifts in Small Mammal Distributions and Biodiversity in the Altered Future Environment of Alaska: An Open Access Data and Machine Learning Perspective

PubMed Central

Baltensperger, A. P.; Huettmann, F.

2015-01-01

Climate change is acting to reallocate biomes, shift the distribution of species, and alter community assemblages in Alaska. Predictions regarding how these changes will affect the biodiversity and interspecific relationships of small mammals are necessary to pro-actively inform conservation planning. We used a set of online occurrence records and machine learning methods to create bioclimatic envelope models for 17 species of small mammals (rodents and shrews) across Alaska. Models formed the basis for sets of species-specific distribution maps for 2010 and were projected forward using the IPCC (Intergovernmental Panel on Climate Change) A2 scenario to predict distributions of the same species for 2100. We found that distributions of cold-climate, northern, and interior small mammal species experienced large decreases in area while shifting northward, upward in elevation, and inland across the state. In contrast, many southern and continental species expanded throughout Alaska, and also moved down-slope and toward the coast. Statewide community assemblages remained constant for 15 of the 17 species, but distributional shifts resulted in novel species assemblages in several regions. Overall biodiversity patterns were similar for both time frames, but followed general species distribution movement trends. Biodiversity losses occurred in the Yukon-Kuskokwim Delta and Seward Peninsula while the Beaufort Coastal Plain and western Brooks Range experienced modest gains in species richness as distributions shifted to form novel assemblages. Quantitative species distribution and biodiversity change projections should help land managers to develop adaptive strategies for conserving dispersal corridors, small mammal biodiversity, and ecosystem functionality into the future. PMID:26207828

Serosurveillance of Scrub Typhus in Small Mammals Collected from Military Training Sites near the DMZ, Northern Gyeonggi-do, Korea, and Analysis of the Relative Abundance of Chiggers from Mammals Examined

DTIC Science & Technology

2010-09-01

Korean J Paras/to/. Vol. 48, No. 3: 237-243, September 2010 DOl: JO.J3471kjp.2010.48.J.237 Serosurveillance of Scrub Typhus in Small Mammals...65th Medical BrigadeAJSAMEDDAC-Korea, Unit# 15281, APO AP 96205-5281, USA Abstract: Comprehensive quarterly serosurveillance on scrub typhus in small...rarely observed (prevalence < 1 0%). In contrast to previous surveys, higher chigger indices of the primary scrub typhus vectors, L. pallidum (165.4

Assessing monkeypox virus prevalence in small mammals at the human-animal interface in the Democratic Republic of the Congo

USGS Publications Warehouse

Doty, Jeffrey B.; Malekani, Jean M.; Kalemba, Lem's N.; Stanley, William T.; Monroe, Benjamin P.; Nakazawa, Yoshinori J.; Mauldin, Matthew R.; Bakambana, Trésor L.; Liyandja Dja Liyandja , Tobit; Braden, Zachary; Wallace, Ryan; 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.

2017-01-01

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. 

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.

Comparative Anatomy of the Bony Labyrinth (Inner Ear) of Placental Mammals

PubMed Central

Ekdale, Eric G.

2013-01-01

Background Variation is a naturally occurring phenomenon that is observable at all levels of morphology, from anatomical variations of DNA molecules to gross variations between whole organisms. The structure of the otic region is no exception. The present paper documents the broad morphological diversity exhibited by the inner ear region of placental mammals using digital endocasts constructed from high-resolution X-ray computed tomography (CT). Descriptions cover the major placental clades, and linear, angular, and volumetric dimensions are reported. Principal Findings The size of the labyrinth is correlated to the overall body mass of individuals, such that large bodied mammals have absolutely larger labyrinths. The ratio between the average arc radius of curvature of the three semicircular canals and body mass of aquatic species is substantially lower than the ratios of related terrestrial taxa, and the volume percentage of the vestibular apparatus of aquatic mammals tends to be less than that calculated for terrestrial species. Aspects of the bony labyrinth are phylogenetically informative, including vestibular reduction in Cetacea, a tall cochlear spiral in caviomorph rodents, a low position of the plane of the lateral semicircular canal compared to the posterior canal in Cetacea and Carnivora, and a low cochlear aspect ratio in Primatomorpha. Significance The morphological descriptions that are presented add a broad baseline of anatomy of the inner ear across many placental mammal clades, for many of which the structure of the bony labyrinth is largely unknown. The data included here complement the growing body of literature on the physiological and phylogenetic significance of bony labyrinth structures in mammals, and they serve as a source of data for future studies on the evolution and function of the vertebrate ear. PMID:23805251

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,...

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.

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.

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

Using stable isotopes to track the effects of deforestation on small-mammal ecology in the Pacific Northwest over the last 100 years

NASA Astrophysics Data System (ADS)

Packard, N. R.; Cotton, J. M.; Smiley, T. M.; Terry, R. C.

2017-12-01

Landscape, land-use, and climate change are important factors in determining ecosystem change over a range of spatio-temporal scales. For example, within small-mammal communities, the spread of agriculture, rapid urbanization, and deforestation have been shown to alter species composition and diet, thus potentially disrupting ecological interactions and reshaping ecosystems. Small mammals integrate the isotopic composition of their diet and drinking water into their hair and therefore serve as useful proxies for vegetation and water resources in their habitat. To better understand how forest loss and land-cover change influence small-mammal ecology in the Pacific Northwest (PNW), we analyzed the hydrogen (H) and oxygen (O) isotopic composition of hair from historical Peromyscus maniculatus (North American deer mouse) specimens housed in natural history museums across the country. While deforestation along the east coast occurred hundreds of years ago, the loss of forests on the west coast occurred more recently, beginning around 1930. We use early 20th century specimens of this widespread and abundant generalist species to better understand ecosystem changes that occurred over the past 100 years of local and regional deforestation. Changing forest composition and structure during deforestation can influence both broad-scale hydrological cycling and local ecosystems. Variation in O and H isotopic composition corresponds to changes in the hydrological cycle, such as changes in the source and amount of precipitation, and changes in the moisture conditions in local ecosystems. We will present this spatial and temporal variability in the form of isoscapes, or δ18O and δD isotope landscape models, of P. maniculatus hair in the western forests of the PNW through time. Investigating isotopic signatures in small mammals can help us better understand ecosystem response to anthropogenic land-use and climate change.

Amphibians at risk? Susceptibility of terrestrial amphibian life stages to pesticides.

PubMed

Brühl, Carsten A; Pieper, Silvia; Weber, Brigitte

2011-11-01

Current pesticide risk assessment does not specifically consider amphibians. Amphibians in the aquatic environment (aquatic life stages or postmetamorphic aquatic amphibians) and terrestrial living juvenile or adult amphibians are assumed to be covered by the risk assessment for aquatic invertebrates and fish, or mammals and birds, respectively. This procedure has been evaluated as being sufficiently protective regarding the acute risk posed by a number of pesticides to aquatic amphibian life stages (eggs, larvae). However, it is unknown whether the exposure and sensitivity of terrestrial living amphibians are comparable to mammalian and avian exposure and sensitivity. We reviewed the literature on dermal pesticide absorption and toxicity studies for terrestrial life stages of amphibians, focusing on the dermal exposure pathway, that is, through treated soil or direct overspray. In vitro studies demonstrated that cutaneous absorption of chemicals is significant and that chemical percutaneous passage, P (cm/h), is higher in amphibians than in mammals. In vivo, the rapid and substantial uptake of the herbicide atrazine from treated soil by toads (Bufo americanus) has been described. Severe toxic effects on various amphibian species have been reported for field-relevant application rates of different pesticides. In general, exposure and toxicity studies for terrestrial amphibian life stages are scarce, and the reported data indicate the need for further research, especially in light of the global amphibian decline. Copyright © 2011 SETAC.

"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.

Geographical Distribution and Seasonal Indices of Chigger Mites on Small Mammals Collected on the East Coast of the Republic of Korea.

PubMed

Park, Gab-Man; Shin, Ho-Sung

2016-04-01

The geographical distributions and relative population densities of scrub typhus vector mites collected from small mammals were determined for 5 locations on the east coast of the Republic of Korea. Collection sites included Goseong, Gangneung, and Hoengseong in Gangwon province and Uljin and Yeongdeok in Gyeongbuk province. A total of 275 small mammals including members of Rodentia (rodents) and Soricomorpha (shrews, such as Crocidura lasiura ) belonging to 4 genera and 4 species were captured in the field from 2012 to 2013. Apodemus agrarius was collected most frequently (220, 80%), followed by C. lasiura (25, 9.1%), Mus musculus (15, 5.5%), and Myodes regulus (15, 5.5%). A total of 23,436 larval chigger mites (Family Trombiculidae) belonging to 3 genera and 8 species (Leptotrombidium pallidum, Leptotrombidium scutellare, Leptotrombidium palpale, Leptotrombidium orientale, Leptotrombidium zetum, Neotrombicula tamiyai, Neotrombicula japonica, and Euschoengastica koreaensis) were collected from the small mammals. The predominant chigger species collected during the spring and fall seasons from A. agrarius were L. pallidum (57.6%), L. palpale (14.5%), and L. scutellare (7.9%). Leptotrombidium scutellare was collected only along the southeastern coast at Yeongdeok, Gyeongbuk province. The geographical distribution of scrub typhus vectors and reservoir hosts are important aspects of understanding the epidemiology of the disease as well as the potential impacts of climate change and health risks.

75 FR 49759 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-13

...In accordance with the Marine Mammal Protection Act (MMPA) regulations, notification is hereby given that NMFS has issued an Incidental Harassment Authorization (IHA) to Statoil USA E&P Inc. (Statoil) to take, by harassment, small numbers of 12 species of marine mammals incidental to a marine seismic survey program in the Chukchi Sea, Alaska, during the 2010 Arctic open water season.

Ecological Interactions in Dinosaur Communities: Influences of Small Offspring and Complex Ontogenetic Life Histories

PubMed Central

Codron, Daryl; Carbone, Chris; Clauss, Marcus

2013-01-01

Because egg-laying meant that even the largest dinosaurs gave birth to very small offspring, they had to pass through multiple ontogenetic life stages to adulthood. Dinosaurs’ successors as the dominant terrestrial vertebrate life form, the mammals, give birth to live young, and have much larger offspring and less complex ontogenetic histories. The larger number of juveniles in dinosaur as compared to mammal ecosystems represents both a greater diversity of food available to predators, and competitors for similar-sized individuals of sympatric species. Models of population abundances across different-sized species of dinosaurs and mammals, based on simulated ecological life tables, are employed to investigate how differences in predation and competition pressure influenced dinosaur communities. Higher small- to medium-sized prey availability leads to a normal body mass-species richness (M-S) distribution of carnivorous dinosaurs (as found in the theropod fossil record), in contrast to the right-skewed M-S distribution of carnivorous mammals (as found living members of the order Carnivora). Higher levels of interspecific competition leads to a left-skewed M-S distribution in herbivorous dinosaurs (as found in sauropods and ornithopods), in contrast to the normal M-S distribution of large herbivorous mammals. Thus, our models suggest that differences in reproductive strategy, and consequently ontogeny, explain observed differences in community structure between dinosaur and mammal faunas. Models also show that the largest dinosaurian predators could have subsisted on similar-sized prey by including younger life stages of the largest herbivore species, but that large predators likely avoided prey much smaller than themselves because, despite predicted higher abundances of smaller than larger-bodied prey, contributions of small prey to biomass intake would be insufficient to satisfy meat requirements. A lack of large carnivores feeding on small prey exists in mammals

Ecological interactions in dinosaur communities: influences of small offspring and complex ontogenetic life histories.

PubMed

Codron, Daryl; Carbone, Chris; Clauss, Marcus

2013-01-01

Because egg-laying meant that even the largest dinosaurs gave birth to very small offspring, they had to pass through multiple ontogenetic life stages to adulthood. Dinosaurs' successors as the dominant terrestrial vertebrate life form, the mammals, give birth to live young, and have much larger offspring and less complex ontogenetic histories. The larger number of juveniles in dinosaur as compared to mammal ecosystems represents both a greater diversity of food available to predators, and competitors for similar-sized individuals of sympatric species. Models of population abundances across different-sized species of dinosaurs and mammals, based on simulated ecological life tables, are employed to investigate how differences in predation and competition pressure influenced dinosaur communities. Higher small- to medium-sized prey availability leads to a normal body mass-species richness (M-S) distribution of carnivorous dinosaurs (as found in the theropod fossil record), in contrast to the right-skewed M-S distribution of carnivorous mammals (as found living members of the order Carnivora). Higher levels of interspecific competition leads to a left-skewed M-S distribution in herbivorous dinosaurs (as found in sauropods and ornithopods), in contrast to the normal M-S distribution of large herbivorous mammals. Thus, our models suggest that differences in reproductive strategy, and consequently ontogeny, explain observed differences in community structure between dinosaur and mammal faunas. Models also show that the largest dinosaurian predators could have subsisted on similar-sized prey by including younger life stages of the largest herbivore species, but that large predators likely avoided prey much smaller than themselves because, despite predicted higher abundances of smaller than larger-bodied prey, contributions of small prey to biomass intake would be insufficient to satisfy meat requirements. A lack of large carnivores feeding on small prey exists in mammals

The maximum rate of mammal evolution

NASA Astrophysics Data System (ADS)

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

2012-03-01

How fast can a mammal evolve from the size of a mouse to the size of an elephant? Achieving such a large transformation calls for major biological reorganization. Thus, the speed at which this occurs has important implications for extensive faunal changes, including adaptive radiations and recovery from mass extinctions. To quantify the pace of large-scale evolution we developed a metric, clade maximum rate, which represents the maximum evolutionary rate of a trait within a clade. We applied this metric to body mass evolution in mammals over the last 70 million years, during which multiple large evolutionary transitions occurred in oceans and on continents and islands. Our computations suggest that it took a minimum of 1.6, 5.1, and 10 million generations for terrestrial mammal mass to increase 100-, and 1,000-, and 5,000-fold, respectively. Values for whales were down to half the length (i.e., 1.1, 3, and 5 million generations), perhaps due to the reduced mechanical constraints of living in an aquatic environment. When differences in generation time are considered, we find an exponential increase in maximum mammal body mass during the 35 million years following the Cretaceous-Paleogene (K-Pg) extinction event. Our results also indicate a basic asymmetry in macroevolution: very large decreases (such as extreme insular dwarfism) can happen at more than 10 times the rate of increases. Our findings allow more rigorous comparisons of microevolutionary and macroevolutionary patterns and processes.

A phylogenetic approach to total evaporative water loss in mammals.

PubMed

Van Sant, Matthew J; Oufiero, Christopher E; Muñoz-Garcia, Agustí; Hammond, Kimberly A; Williams, Joseph B

2012-01-01

Maintaining appropriate water balance is a constant challenge for terrestrial mammals, and this problem can be exacerbated in desiccating environments. It has been proposed that natural selection has provided desert-dwelling mammals physiological mechanisms to reduce rates of total evaporative water loss. In this study, we evaluated the relationship between total evaporative water loss and body mass in mammals by using a recent phylogenetic hypothesis. We compared total evaporative water loss in 80 species of arid-zone mammals to that in 56 species that inhabit mesic regions, ranging in size from 4 g to 3,500 kg, to test the hypothesis that mammals from arid environments have lower rates of total evaporative water loss than mammals from mesic environments once phylogeny is taken into account. We found that arid species had lower rates of total evaporative water loss than mesic species when using a dichotomous variable to describe habitat (arid or mesic). We also found that total evaporative water loss was negatively correlated with the average maximum and minimum environmental temperature as well as the maximum vapor pressure deficit of the environment. Annual precipitation and the variable Q (a measure of habitat aridity) were positively correlated with total evaporative water loss. These results support the hypothesis that desert-dwelling mammals have lower rates of total evaporative water loss than mesic species after controlling for body mass and evolutionary relatedness regardless of whether categorical or continuous variables are used to describe habitat.

Posture does not matter! Paw usage and grasping paw preference in a small-bodied rooting quadrupedal mammal.

PubMed

Joly, Marine; Scheumann, Marina; Zimmermann, Elke

2012-01-01

Recent results in birds, marsupials, rodents and nonhuman primates suggest that phylogeny and ecological factors such as body size, diet and postural habit of a species influence limb usage and the direction and strength of limb laterality. To examine to which extent these findings can be generalised to small-bodied rooting quadrupedal mammals, we studied trees shrews (Tupaia belangeri). We established a behavioural test battery for examining paw usage comparable to small-bodied primates and tested 36 Tupaia belangeri. We studied paw usage in a natural foraging situation (simple food grasping task) and measured the influence of varying postural demands (triped, biped, cling, sit) on paw preferences by applying a forced-food grasping task similar to other small-bodied primates. Our findings suggest that rooting tree shrews prefer mouth over paw usage to catch food in a natural foraging situation. Moreover, we demonstrated that despite differences in postural demand, tree shrews show a strong and consistent individual paw preference for grasping across different tasks, but no paw preference at a population level. Tree shrews showed less paw usage than small-bodied quadrupedal and arboreal primates, but the same paw preference. Our results confirm that individual paw preferences remain constant irrespective of postural demand in some small-bodied quadrupedal non primate and primate mammals which do not require fine motoric control for manipulating food items. Our findings suggest that the lack of paw/hand preference for grasping food at a population level is a universal pattern among those species and that the influence of postural demand on manual lateralisation in quadrupeds may have evolved in large-bodied species specialised in fine manipulations of food items.

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…

75 FR 16754 - Taking and Importing Marine Mammals; Taking of Marine Mammals Incidental to Conducting Precision...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-02

... the Small Diameter Bomb (SDB) exercise under the PSW LOA. Three Griffin\\TM\\ SOPGM system missiles with..., taking of small numbers of marine mammals by U.S. citizens who engage in a specified activity (other than... (Public Law 108-136) removed the ``small numbers'' and ``specified geographical region'' limitations and...

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...

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-...

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.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.

Diversity and Impacts of Mining on the Non-Volant Small Mammal Communities of Two Vegetation Types in the Brazilian Amazon.

PubMed

Ardente, Natália Carneiro; Ferreguetti, Átilla Colombo; Gettinger, Donald; Leal, Pricila; Mendes-Oliveira, Ana Cristina; Martins-Hatano, Fernanda; Bergallo, Helena Godoy

2016-01-01

The Carajás National Forest contains some of the largest iron ore deposits in the world. The majority of the minerals are found below a plant community known as Savana Metalófila, or "Canga", which represents only 3% of the landscape within the Carajás National Forest (CNF). The aim of our study was to understand the diversity of community of non-volant small mammals in the two predominant vegetation types: Ombrophilous Forest and Canga, and to examine how mining impacts these communities. Sampling was conducted from January 2010 to August 2011 in 11 sampling sites divided by the total area of Canga and 12 sampling sites in the forest, totalizing 23 sites. Of these, 12 sites (Canga and Forest) were considered impacted areas located close to the mine (< 900 meters) and 11 sites (Canga and Forest), serving as controls, which were at least 7,000 meters from the mine. We recorded 28 species, 11 from the Order Didelphimorphia and 17 from the Order Rodentia. The two forest types shared 68.42% of the species found in the CNF. A gradient analysis (Non-metric multidimensional scaling) revealed that the first axis clearly separated the non-flying small mammal communities by vegetation type. Occupancy models showed that the detectability of species was affected by the distance from the mining activities. Of all the small mammals analyzed, 10 species were positively affected by the distance from mining in areas impacted (e.g. more likely to be detected farther from mining areas) and detectability was lower in impacted areas. However, three species were negatively affected by the distance from mining, with higher detectability in the impacted areas, and seven species showed no effect of their proximity to mining operations. To date, there are no studies in Brazil about the impact of mining on mammals or other vertebrates. This study reveals that the effect of mining may go beyond the forest destruction caused by the opening of the mining pits, but also may negatively affect

Diversity and Impacts of Mining on the Non-Volant Small Mammal Communities of Two Vegetation Types in the Brazilian Amazon

PubMed Central

Ardente, Natália Carneiro; Ferreguetti, Átilla Colombo; Gettinger, Donald; Leal, Pricila; Mendes-Oliveira, Ana Cristina; Martins-Hatano, Fernanda; Bergallo, Helena Godoy

2016-01-01

The Carajás National Forest contains some of the largest iron ore deposits in the world. The majority of the minerals are found below a plant community known as Savana Metalófila, or “Canga”, which represents only 3% of the landscape within the Carajás National Forest (CNF). The aim of our study was to understand the diversity of community of non-volant small mammals in the two predominant vegetation types: Ombrophilous Forest and Canga, and to examine how mining impacts these communities. Sampling was conducted from January 2010 to August 2011 in 11 sampling sites divided by the total area of Canga and 12 sampling sites in the forest, totalizing 23 sites. Of these, 12 sites (Canga and Forest) were considered impacted areas located close to the mine (<< 900 meters) and 11 sites (Canga and Forest), serving as controls, which were at least 7,000 meters from the mine. We recorded 28 species, 11 from the Order Didelphimorphia and 17 from the Order Rodentia. The two forest types shared 68.42% of the species found in the CNF. A gradient analysis (Non-metric multidimensional scaling) revealed that the first axis clearly separated the non-flying small mammal communities by vegetation type. Occupancy models showed that the detectability of species was affected by the distance from the mining activities. Of all the small mammals analyzed, 10 species were positively affected by the distance from mining in areas impacted (e.g. more likely to be detected farther from mining areas) and detectability was lower in impacted areas. However, three species were negatively affected by the distance from mining, with higher detectability in the impacted areas, and seven species showed no effect of their proximity to mining operations. To date, there are no studies in Brazil about the impact of mining on mammals or other vertebrates. This study reveals that the effect of mining may go beyond the forest destruction caused by the opening of the mining pits, but also may negatively

Strong evidence for terrestrial support of zooplankton in small lakes based on stable isotopes of carbon, nitrogen, and hydrogen

USGS Publications Warehouse

Cole, J.J.; Carpenter, S.R.; Kitchell, J.; Pace, M.L.; Solomon, C.T.; Weidel, B.

2011-01-01

Cross-ecosystem subsidies to food webs can alter metabolic balances in the receiving (subsidized) system and free the food web, or particular consumers, from the energetic constraints of local primary production. Although cross-ecosystem subsidies between terrestrial and aquatic systems have been well recognized for benthic organisms in streams, rivers, and the littoral zones of lakes, terrestrial subsidies to pelagic consumers are more difficult to demonstrate and remain controversial. Here, we adopt a unique approach by using stable isotopes of H, C, and N to estimate terrestrial support to zooplankton in two contrasting lakes. Zooplankton (Holopedium, Daphnia, and Leptodiaptomus) are comprised of ???20-40% of organic material of terrestrial origin. These estimates are as high as, or higher than, prior measures obtained by experimentally manipulating the inorganic 13C content of these lakes to augment the small, natural contrast in 13C between terrestrial and algal photosynthesis. Our study gives credence to a growing literature, which we review here, suggesting that significant terrestrial support of pelagic crustaceans (zooplankton) is widespread.

Strong evidence for terrestrial support of zooplankton in small lakes based on stable isotopes of carbon, nitrogen, and hydrogen

PubMed Central

Cole, Jonathan J.; Carpenter, Stephen R.; Kitchell, Jim; Pace, Michael L.; Solomon, Christopher T.; Weidel, Brian

2011-01-01

Cross-ecosystem subsidies to food webs can alter metabolic balances in the receiving (subsidized) system and free the food web, or particular consumers, from the energetic constraints of local primary production. Although cross-ecosystem subsidies between terrestrial and aquatic systems have been well recognized for benthic organisms in streams, rivers, and the littoral zones of lakes, terrestrial subsidies to pelagic consumers are more difficult to demonstrate and remain controversial. Here, we adopt a unique approach by using stable isotopes of H, C, and N to estimate terrestrial support to zooplankton in two contrasting lakes. Zooplankton (Holopedium, Daphnia, and Leptodiaptomus) are comprised of ≈20–40% of organic material of terrestrial origin. These estimates are as high as, or higher than, prior measures obtained by experimentally manipulating the inorganic 13C content of these lakes to augment the small, natural contrast in 13C between terrestrial and algal photosynthesis. Our study gives credence to a growing literature, which we review here, suggesting that significant terrestrial support of pelagic crustaceans (zooplankton) is widespread. PMID:21245299

Protection of mammal diversity in Central America

USGS Publications Warehouse

Jenkins, Clinton N.; Giri, Chandra

2008-01-01

Central America is exceptionally rich in biodiversity, but varies widely in the attention its countries devote to conservation. Protected areas, widely considered the cornerstone of conservation, were not always created with the intent of conserving that biodiversity. We assessed how well the protected-area system of Central America includes the region's mammal diversity. This first required a refinement of existing range maps to reduce their extensive errors of commission (i.e., predicted presences in places where species do not occur). For this refinement, we used the ecological limits of each species to identify and remove unsuitable areas from the range. We then compared these maps with the locations of protected areas to measure the habitat protected for each of the region's 250 endemic mammals. The species most vulnerable to extinction—those with small ranges—were largely outside protected areas. Nevertheless, the most strictly protected areas tended toward areas with many small-ranged species. To improve the protection coverage of mammal diversity in the region, we identified a set of priority sites that would best complement the existing protected areas. Protecting these new sites would require a relatively small increase in the total area protected, but could greatly enhance mammal conservation.

Trunk orientation causes asymmetries in leg function in small bird terrestrial locomotion.

PubMed

Andrada, Emanuel; Rode, Christian; Sutedja, Yefta; Nyakatura, John A; Blickhan, Reinhard

2014-12-22

In contrast to the upright trunk in humans, trunk orientation in most birds is almost horizontal (pronograde). It is conceivable that the orientation of the heavy trunk strongly influences the dynamics of bipedal terrestrial locomotion. Here, we analyse for the first time the effects of a pronograde trunk orientation on leg function and stability during bipedal locomotion. For this, we first inferred the leg function and trunk control strategy applied by a generalized small bird during terrestrial locomotion by analysing synchronously recorded kinematic (three-dimensional X-ray videography) and kinetic (three-dimensional force measurement) quail locomotion data. Then, by simulating quail gaits using a simplistic bioinspired numerical model which made use of parameters obtained in in vivo experiments with real quail, we show that the observed asymmetric leg function (left-skewed ground reaction force and longer leg at touchdown than at lift-off) is necessary for pronograde steady-state locomotion. In addition, steady-state locomotion becomes stable for specific morphological parameters. For quail-like parameters, the most common stable solution is grounded running, a gait preferred by quail and most of the other small birds. We hypothesize that stability of bipedal locomotion is a functional demand that, depending on trunk orientation and centre of mass location, constrains basic hind limb morphology and function, such as leg length, leg stiffness and leg damping. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Relating Demographic Characteristics of a Small Mammal to Remotely Sensed Forest-Stand Condition

PubMed Central

Lada, Hania; Thomson, James R.; Cunningham, Shaun C.; Mac Nally, Ralph

2014-01-01

Many ecological systems around the world are changing rapidly in response to direct (land-use change) and indirect (climate change) human actions. We need tools to assess dynamically, and over appropriate management scales, condition of ecosystems and their responses to potential mitigation of pressures. Using a validated model, we determined whether stand condition of floodplain forests is related to densities of a small mammal (a carnivorous marsupial, Antechinus flavipes) in 60 000 ha of extant river red gum (Eucalyptus camaldulensis) forests in south-eastern Australia in 2004, 2005 and 2011. Stand condition was assessed remotely using models built from ground assessments of stand condition and satellite-derived reflectance. Other covariates, such as volumes of fallen timber, distances to floods, rainfall and life stages were included in the model. Trapping of animals was conducted at 272 plots (0.25 ha) across the region. Densities of second-year females (i.e. females that had survived to a second breeding year) and of second-year females with suckled teats (i.e. inferred to have been successful mothers) were higher in stands with the highest condition. There was no evidence of a relationship with stand condition for males or all females. These outcomes show that remotely-sensed estimates of stand condition (here floodplain forests) are relatable to some demographic characteristics of a small mammal species, and may provide useful information about the capacity of ecosystems to support animal populations. Over-regulation of large, lowland rivers has led to declines in many facets of floodplain function. If management of water resources continues as it has in recent decades, then our results suggest that there will be further deterioration in stand condition and a decreased capacity for female yellow-footed antechinuses to breed multiple times. PMID:24621967

Unifying principles in terrestrial locomotion: do hopping Australian marsupials fit in?

PubMed

Bennett, M B

2000-01-01

Mammalian terrestrial locomotion has many unifying principles. However, the Macropodoidea are a particularly interesting group that exhibit a number of significant deviations from the principles that seem to apply to other mammals. While the properties of materials that comprise the musculoskeletal system of mammals are similar, evidence suggests that tendon properties in macropodoid marsupials may be size or function dependent, in contrast to the situation in placental mammals. Postural differences related to hopping versus running have a dramatic effect on the scaling of the pelvic limb musculoskeletal system. Ratios of muscle fibre to tendon cross-sectional areas for ankle extensors and digital flexors scale with positive allometry in all mammals, but exponents are significantly higher in macropods. Tendon safety factors decline with increasing body mass in mammals, with eutherians at risk of ankle extensor tendon rupture at a body mass of about 150 kg, whereas kangaroos encounter similar problems at a body mass of approximately 35 kg. Tendon strength appears to limit locomotor performance in these animals. Elastic strain energy storage in tendons is mass dependent in all mammals, but exponents are significantly larger in macropodid. Tibial stresses may scale with positive allometry in kangaroos, which result in lower bone safety factors in macropods compared to eutherian mammals.

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

Invasive mammal eradication on islands results in substantial conservation gains

PubMed Central

Jones, Holly P.; Holmes, Nick D.; Butchart, Stuart H. M.; Tershy, Bernie R.; Kappes, Peter J.; Corkery, Ilse; Aguirre-Muñoz, Alfonso; Armstrong, Doug P.; Bonnaud, Elsa; Burbidge, Andrew A.; Campbell, Karl; Courchamp, Franck; Cowan, Philip E.; Cuthbert, Richard J.; Ebbert, Steve; Genovesi, Piero; Howald, Gregg R.; Keitt, Bradford S.; Kress, Stephen W.; Miskelly, Colin M.; Oppel, Steffen; Poncet, Sally; Rauzon, Mark J.; Rocamora, Gérard; Russell, James C.; Samaniego-Herrera, Araceli; Seddon, Philip J.; Spatz, Dena R.; Towns, David R.; Croll, Donald A.

2016-01-01

More than US$21 billion is spent annually on biodiversity conservation. Despite their importance for preventing or slowing extinctions and preserving biodiversity, conservation interventions are rarely assessed systematically for their global impact. Islands house a disproportionately higher amount of biodiversity compared with mainlands, much of which is highly threatened with extinction. Indeed, island species make up nearly two-thirds of recent extinctions. Islands therefore are critical targets of conservation. We used an extensive literature and database review paired with expert interviews to estimate the global benefits of an increasingly used conservation action to stem biodiversity loss: eradication of invasive mammals on islands. We found 236 native terrestrial insular faunal species (596 populations) that benefitted through positive demographic and/or distributional responses from 251 eradications of invasive mammals on 181 islands. Seven native species (eight populations) were negatively impacted by invasive mammal eradication. Four threatened species had their International Union for the Conservation of Nature (IUCN) Red List extinction-risk categories reduced as a direct result of invasive mammal eradication, and no species moved to a higher extinction-risk category. We predict that 107 highly threatened birds, mammals, and reptiles on the IUCN Red List—6% of all these highly threatened species—likely have benefitted from invasive mammal eradications on islands. Because monitoring of eradication outcomes is sporadic and limited, the impacts of global eradications are likely greater than we report here. Our results highlight the importance of invasive mammal eradication on islands for protecting the world's most imperiled fauna. PMID:27001852

Invasive mammal eradication on islands results in substantial conservation gains.

PubMed

Jones, Holly P; Holmes, Nick D; Butchart, Stuart H M; Tershy, Bernie R; Kappes, Peter J; Corkery, Ilse; Aguirre-Muñoz, Alfonso; Armstrong, Doug P; Bonnaud, Elsa; Burbidge, Andrew A; Campbell, Karl; Courchamp, Franck; Cowan, Philip E; Cuthbert, Richard J; Ebbert, Steve; Genovesi, Piero; Howald, Gregg R; Keitt, Bradford S; Kress, Stephen W; Miskelly, Colin M; Oppel, Steffen; Poncet, Sally; Rauzon, Mark J; Rocamora, Gérard; Russell, James C; Samaniego-Herrera, Araceli; Seddon, Philip J; Spatz, Dena R; Towns, David R; Croll, Donald A

2016-04-12

More than US$21 billion is spent annually on biodiversity conservation. Despite their importance for preventing or slowing extinctions and preserving biodiversity, conservation interventions are rarely assessed systematically for their global impact. Islands house a disproportionately higher amount of biodiversity compared with mainlands, much of which is highly threatened with extinction. Indeed, island species make up nearly two-thirds of recent extinctions. Islands therefore are critical targets of conservation. We used an extensive literature and database review paired with expert interviews to estimate the global benefits of an increasingly used conservation action to stem biodiversity loss: eradication of invasive mammals on islands. We found 236 native terrestrial insular faunal species (596 populations) that benefitted through positive demographic and/or distributional responses from 251 eradications of invasive mammals on 181 islands. Seven native species (eight populations) were negatively impacted by invasive mammal eradication. Four threatened species had their International Union for the Conservation of Nature (IUCN) Red List extinction-risk categories reduced as a direct result of invasive mammal eradication, and no species moved to a higher extinction-risk category. We predict that 107 highly threatened birds, mammals, and reptiles on the IUCN Red List-6% of all these highly threatened species-likely have benefitted from invasive mammal eradications on islands. Because monitoring of eradication outcomes is sporadic and limited, the impacts of global eradications are likely greater than we report here. Our results highlight the importance of invasive mammal eradication on islands for protecting the world's most imperiled fauna.

Where and How Are Roads Endangering Mammals in Southeast Asia's Forests?

PubMed Central

Clements, Gopalasamy Reuben; Lynam, Antony J.; Gaveau, David; Yap, Wei Lim; Lhota, Stanislav; Goosem, Miriam; Laurance, Susan; Laurance, William F.

2014-01-01

Habitat destruction and overhunting are two major drivers of mammal population declines and extinctions in tropical forests. The construction of roads can be a catalyst for these two threats. In Southeast Asia, the impacts of roads on mammals have not been well-documented at a regional scale. Before evidence-based conservation strategies can be developed to minimize the threat of roads to endangered mammals within this region, we first need to locate where and how roads are contributing to the conversion of their habitats and illegal hunting in each country. We interviewed 36 experts involved in mammal research from seven Southeast Asian countries to identify roads that are contributing the most, in their opinion, to habitat conversion and illegal hunting. Our experts highlighted 16 existing and eight planned roads - these potentially threaten 21% of the 117 endangered terrestrial mammals in those countries. Apart from gathering qualitative evidence from the literature to assess their claims, we demonstrate how species-distribution models, satellite imagery and animal-sign surveys can be used to provide quantitative evidence of roads causing impacts by (1) cutting through habitats where endangered mammals are likely to occur, (2) intensifying forest conversion, and (3) contributing to illegal hunting and wildlife trade. To our knowledge, ours is the first study to identify specific roads threatening endangered mammals in Southeast Asia. Further through highlighting the impacts of roads, we propose 10 measures to limit road impacts in the region. PMID:25521297

Where and how are roads endangering mammals in Southeast Asia's forests?

PubMed

Clements, Gopalasamy Reuben; Lynam, Antony J; Gaveau, David; Yap, Wei Lim; Lhota, Stanislav; Goosem, Miriam; Laurance, Susan; Laurance, William F

2014-01-01

Habitat destruction and overhunting are two major drivers of mammal population declines and extinctions in tropical forests. The construction of roads can be a catalyst for these two threats. In Southeast Asia, the impacts of roads on mammals have not been well-documented at a regional scale. Before evidence-based conservation strategies can be developed to minimize the threat of roads to endangered mammals within this region, we first need to locate where and how roads are contributing to the conversion of their habitats and illegal hunting in each country. We interviewed 36 experts involved in mammal research from seven Southeast Asian countries to identify roads that are contributing the most, in their opinion, to habitat conversion and illegal hunting. Our experts highlighted 16 existing and eight planned roads - these potentially threaten 21% of the 117 endangered terrestrial mammals in those countries. Apart from gathering qualitative evidence from the literature to assess their claims, we demonstrate how species-distribution models, satellite imagery and animal-sign surveys can be used to provide quantitative evidence of roads causing impacts by (1) cutting through habitats where endangered mammals are likely to occur, (2) intensifying forest conversion, and (3) contributing to illegal hunting and wildlife trade. To our knowledge, ours is the first study to identify specific roads threatening endangered mammals in Southeast Asia. Further through highlighting the impacts of roads, we propose 10 measures to limit road impacts in the region.

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

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

Melting phase relations in the Fe-S and Fe-S-O systems at core conditions in small terrestrial bodies

NASA Astrophysics Data System (ADS)

Pommier, Anne; Laurenz, Vera; Davies, Christopher J.; Frost, Daniel J.

2018-05-01

We report an experimental investigation of phase equilibria in the Fe-S and Fe-S-O systems. Experiments were performed at high temperatures (1400-1850 °C) and high pressures (14 and 20 GPa) using a multi-anvil apparatus. The results of this study are used to understand the effect of sulfur and oxygen on core dynamics in small terrestrial bodies. We observe that the formation of solid FeO grains occurs at the Fe-S liquid - Fe solid interface at high temperature ( > 1400 °C at 20 GPa). Oxygen fugacities calculated for each O-bearing sample show that redox conditions vary from ΔIW = -0.65 to 0. Considering the relative density of each phase and existing evolutionary models of terrestrial cores, we apply our experimental results to the cores of Mars and Ganymede. We suggest that the presence of FeO in small terrestrial bodies tends to contribute to outer-core compositional stratification. Depending on the redox and thermal history of the planet, FeO may also help form a transitional redox zone at the core-mantle boundary.

Deposition and Burial Efficiency of Terrestrial Organic Carbon Exported from Small Mountainous Rivers to the Continental Margin, Southwest of Taiwan

NASA Astrophysics Data System (ADS)

Hsu, F.; Lin, S.; Wang, C.; Huh, C.

2007-12-01

Terrestrial organic carbon exported from small mountainous river to the continental margin may play an important role in global carbon cycle and it?|s biogeochemical process. A huge amount of suspended materials from small rivers in southwestern Taiwan (104 million tons per year) could serve as major carbon source to the adjacent ocean. However, little is know concerning fate of this terrigenous organic carbon. The purpose of this study is to calculate flux of terrigenous organic carbon deposited in the continental margin, offshore southwestern Taiwan through investigating spatial variation of organic carbon content, organic carbon isotopic compositions, organic carbon deposition rate and burial efficiency. Results show that organic carbon compositions in sediment are strongly influenced by terrestrial material exported from small rivers in the region, Kaoping River, Tseng-wen River and Er-jan Rver. In addition, a major part of the terrestrial materials exported from the Kaoping River may bypass shelf region and transport directly into the deep sea (South China Sea) through the Kaoping Canyon. Organic carbon isotopic compositions with lighter carbon isotopic values are found near the Kaoping River and Tseng-wen River mouth and rapidly change from heavier to lighter values through shelf to slope. Patches of lighter organic carbon isotopic compositions with high organic carbon content are also found in areas west of Kaoping River mouth, near the Kaoshiung city. Furthermore, terrigenous organic carbons with lighter isotopic values are found in the Kaoping canyon. A total of 0.028 Mt/yr of terrestrial organic carbon was found in the study area, which represented only about 10 percent of all terrestrial organic carbon deposited in the study area. Majority (~90 percent) of the organic carbon exported from the Kaoping River maybe directly transported into the deep sea (South China Sea) and become a major source of organic carbon in the deep sea.

Paleoenvironmental reconstruction of the early Neolithic to middle Bronze Age Peña Larga rock shelter (Álava, Spain) from the small mammal record

NASA Astrophysics Data System (ADS)

Rofes, Juan; Zuluaga, Mari Cruz; Murelaga, Xabier; Fernández-Eraso, Javier; Bailon, Salvador; Iriarte, María José; Ortega, Luis Ángel; Alonso-Olazabal, Ainhoa

2013-03-01

The Peña Larga site, a rock shelter on the southern slopes of the Cantabrian cordillera (north Spain), is an archeological deposit covering nearly 4000 years, from the early Neolithic to the middle Bronze Age (Atlantic/Subboreal chronozones). It was used both as a household and as a stable, with a hiatus in the Chalcolithic when it was used as a collective sepulcher. Nearly twenty-eight thousand small vertebrate elements were recovered from its seven stratigraphic units, of which 2553 items were identified to the genus and/or species levels. The assemblage is composed of mammals, birds, reptiles, and amphibians. Of these, small mammals were used for paleoenvironmental reconstruction since they are very sensitive to climatic conditions, the sample sizes are large, and their preservation is good. Their distributions over time, measured in terms of relative abundance, serve as reliable proxies of habitat and climate change. The reconstruction of Peña Larga's past environments based on small mammals roughly coincides with the pollen and the amphibian/reptile records on the local scale, and with that of an ice core from Central Greenland on the global scale. This makes it a valuable tool for comparative purposes both in the regional and continental scales.

Energetic tradeoffs control the size distribution of aquatic mammals

NASA Astrophysics Data System (ADS)

Gearty, William; McClain, Craig R.; Payne, Jonathan L.

2018-04-01

Four extant lineages of mammals have invaded and diversified in the water: Sirenia, Cetacea, Pinnipedia, and Lutrinae. Most of these aquatic clades are larger bodied, on average, than their closest land-dwelling relatives, but the extent to which potential ecological, biomechanical, and physiological controls contributed to this pattern remains untested quantitatively. Here, we use previously published data on the body masses of 3,859 living and 2,999 fossil mammal species to examine the evolutionary trajectories of body size in aquatic mammals through both comparative phylogenetic analysis and examination of the fossil record. Both methods indicate that the evolution of an aquatic lifestyle is driving three of the four extant aquatic mammal clades toward a size attractor at ˜500 kg. The existence of this body size attractor and the relatively rapid selection toward, and limited deviation from, this attractor rule out most hypothesized drivers of size increase. These three independent body size increases and a shared aquatic optimum size are consistent with control by differences in the scaling of energetic intake and cost functions with body size between the terrestrial and aquatic realms. Under this energetic model, thermoregulatory costs constrain minimum size, whereas limitations on feeding efficiency constrain maximum size. The optimum size occurs at an intermediate value where thermoregulatory costs are low but feeding efficiency remains high. Rather than being released from size pressures, water-dwelling mammals are driven and confined to larger body sizes by the strict energetic demands of the aquatic medium.

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

Phenotypic plasticity of post-fire activity and thermal biology of a free-ranging small mammal.

PubMed

Stawski, Clare; Körtner, Gerhard; Nowack, Julia; Geiser, Fritz

2016-05-15

Ecosystems can change rapidly and sometimes irreversibly due to a number of anthropogenic and natural factors, such as deforestation and fire. How individual animals exposed to such changes respond behaviourally and physiologically is poorly understood. We quantified the phenotypic plasticity of activity patterns and torpor use - a highly efficient energy conservation mechanism - in brown antechinus (Antechinus stuartii), a small Australian marsupial mammal. We compared groups in densely vegetated forest areas (pre-fire and control) with a group in a burned, open habitat (post-fire). Activity and torpor patterns differed among groups and sexes. Females in the post-fire group spent significantly less time active than the other groups, both during the day and night. However, in males only daytime activity declined in the post-fire group, although overall activity was also reduced on cold days in males for all groups. The reduction in total or diurnal activity in the post-fire group was made energetically possible by a ~3.4-fold and ~2.2-fold increase in the proportion of time females and males, respectively, used torpor in comparison to that in the pre-fire and control groups. Overall, likely due to reproductive needs, torpor was more pronounced in females than in males, but low ambient temperatures increased torpor bout duration in both sexes. Importantly, for both male and female antechinus and likely other small mammals, predator avoidance and energy conservation - achieved by reduced activity and increased torpor use - appear to be vital for post-fire survival where ground cover and refuges have been obliterated. Copyright © 2016 Elsevier Inc. All rights reserved.

Wilderness ecology: the upland plant communities, woody browse production, and small mammals of two adjacent 33-year-old wildfire areas of northeastern Minnesota.

Treesearch

Lewis F. Ohmann; Charles T. Cushwa; Roger E. Lake; James R. Beer; Robert B. Brander

1973-01-01

In three parts, classifies the upland vegetation into four community types; describes the measurements of browse and gives yields by different species; and describes the relation of small mammal populations to vegetative community types.

A unique resource mutualism between the giant Bornean pitcher plant, Nepenthes rajah, and members of a small mammal community.

PubMed

Greenwood, Melinda; Clarke, Charles; Lee, Ch'ien C; Gunsalam, Ansou; Clarke, Rohan H

2011-01-01

The carnivorous pitcher plant genus Nepenthes grows in nutrient-deficient substrates and produce jug-shaped leaf organs (pitchers) that trap arthropods as a source of N and P. A number of Bornean Nepenthes demonstrate novel nutrient acquisition strategies. Notably, three giant montane species are engaged in a mutualistic association with the mountain treeshrew, Tupaia montana, in which the treeshrew defecates into the pitchers while visiting them to feed on nectar secretions on the pitchers' lids.Although the basis of this resource mutualism has been elucidated, many aspects are yet to be investigated. We sought to provide insights into the value of the mutualism to each participant. During initial observations we discovered that the summit rat, R. baluensis, also feeds on sugary exudates of N. rajah pitchers and defecates into them, and that this behavior appears to be habitual. The scope of the study was therefore expanded to assess to what degree N. rajah interacts with the small mammal community.We found that both T. montana and R. baluensis are engaged in a mutualistic interaction with N. rajah. T .montana visit pitchers more frequently than R. baluensis, but daily scat deposition rates within pitchers do not differ, suggesting that the mutualistic relationships are of a similar strength. This study is the first to demonstrate that a mutualism exists between a carnivorous plant species and multiple members of a small mammal community. Further, the newly discovered mutualism between R. baluensis and N. rajah represents only the second ever example of a multidirectional resource-based mutualism between a mammal and a carnivorous plant.

A Unique Resource Mutualism between the Giant Bornean Pitcher Plant, Nepenthes rajah, and Members of a Small Mammal Community

PubMed Central

Greenwood, Melinda; Clarke, Charles; Lee, Ch'ien C.; Gunsalam, Ansou; Clarke, Rohan H.

2011-01-01

The carnivorous pitcher plant genus Nepenthes grows in nutrient-deficient substrates and produce jug-shaped leaf organs (pitchers) that trap arthropods as a source of N and P. A number of Bornean Nepenthes demonstrate novel nutrient acquisition strategies. Notably, three giant montane species are engaged in a mutualistic association with the mountain treeshrew, Tupaia montana, in which the treeshrew defecates into the pitchers while visiting them to feed on nectar secretions on the pitchers' lids. Although the basis of this resource mutualism has been elucidated, many aspects are yet to be investigated. We sought to provide insights into the value of the mutualism to each participant. During initial observations we discovered that the summit rat, R. baluensis, also feeds on sugary exudates of N. rajah pitchers and defecates into them, and that this behavior appears to be habitual. The scope of the study was therefore expanded to assess to what degree N. rajah interacts with the small mammal community. We found that both T. montana and R. baluensis are engaged in a mutualistic interaction with N. rajah. T .montana visit pitchers more frequently than R. baluensis, but daily scat deposition rates within pitchers do not differ, suggesting that the mutualistic relationships are of a similar strength. This study is the first to demonstrate that a mutualism exists between a carnivorous plant species and multiple members of a small mammal community. Further, the newly discovered mutualism between R. baluensis and N. rajah represents only the second ever example of a multidirectional resource-based mutualism between a mammal and a carnivorous plant. PMID:21695073

What lies beneath: sub-articular long bone shape scaling in eutherian mammals and saurischian dinosaurs suggests different locomotor adaptations for gigantism.

PubMed

Bonnan, Matthew F; Wilhite, D Ray; Masters, Simon L; Yates, Adam M; Gardner, Christine K; Aguiar, Adam

2013-01-01

Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in saurischian dinosaurs, differences that could have contributed to, or limited, how frequently gigantism evolved. Therefore, we tested the hypothesis that sub-articular bone, which supports the articular cartilage, changes shape in different ways between terrestrial mammals and dinosaurs with increasing size. Our sample consisted of giant mammal and reptile taxa (i.e., elephants, rhinos, sauropods) plus erect and non-erect outgroups with thin and thick articular cartilage. Our results show that eutherian mammal sub-articular shape becomes narrow with well-defined surface features as size increases. In contrast, this region in saurischian dinosaurs expands and remains gently convex with increasing size. Similar trends were observed in non-erect outgroup taxa (monotremes, alligators), showing that the trends we report are posture-independent. These differences support our hypothesis that sub-articular shape scales differently between eutherian mammals and saurischian dinosaurs. Our results show that articular cartilage thickness and sub-articular shape are correlated. In mammals, joints become ever more congruent and thinner with increasing size, whereas archosaur joints remained both congruent and thick, especially in sauropods. We suggest that gigantism occurs less frequently in mammals, in part, because joints composed of thin articular cartilage can only become so congruent before stress cannot be effectively alleviated. In contrast, frequent gigantism in saurischian dinosaurs may be explained, in part, by joints with thick articular cartilage that can deform across large areas with increasing load.

What Lies Beneath: Sub-Articular Long Bone Shape Scaling in Eutherian Mammals and Saurischian Dinosaurs Suggests Different Locomotor Adaptations for Gigantism

PubMed Central

Bonnan, Matthew F.; Wilhite, D. Ray; Masters, Simon L.; Yates, Adam M.; Gardner, Christine K.; Aguiar, Adam

2013-01-01

Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in saurischian dinosaurs, differences that could have contributed to, or limited, how frequently gigantism evolved. Therefore, we tested the hypothesis that sub-articular bone, which supports the articular cartilage, changes shape in different ways between terrestrial mammals and dinosaurs with increasing size. Our sample consisted of giant mammal and reptile taxa (i.e., elephants, rhinos, sauropods) plus erect and non-erect outgroups with thin and thick articular cartilage. Our results show that eutherian mammal sub-articular shape becomes narrow with well-defined surface features as size increases. In contrast, this region in saurischian dinosaurs expands and remains gently convex with increasing size. Similar trends were observed in non-erect outgroup taxa (monotremes, alligators), showing that the trends we report are posture-independent. These differences support our hypothesis that sub-articular shape scales differently between eutherian mammals and saurischian dinosaurs. Our results show that articular cartilage thickness and sub-articular shape are correlated. In mammals, joints become ever more congruent and thinner with increasing size, whereas archosaur joints remained both congruent and thick, especially in sauropods. We suggest that gigantism occurs less frequently in mammals, in part, because joints composed of thin articular cartilage can only become so congruent before stress cannot be effectively alleviated. In contrast, frequent gigantism in saurischian dinosaurs may be explained, in part, by joints with thick articular cartilage that can deform across large areas with increasing load. PMID:24130690

What Makes a Mammal a Mammal?

ERIC Educational Resources Information Center

Naturescope, 1986

1986-01-01

Describes the distinctive characteristics of mammals and compares modern mammals with their prehistoric relatives as well as with other animal groups. Includes activities and ready-to-copy games, illustrations, and diagrams of wolves, vertebrates, and past and present mammals. (ML)

Initial response of small ground-dwelling mammals to forest alternative buffers along headwater streams in the Washington Coast Range, USA

Treesearch

Randall J. Wilk; Martin G. Raphael; Christopher S. Nations; Jeffrey D. Ricklefs

2010-01-01

We assessed the short-term effects of alternative designs of forested buffer treatments along headwater streams on small ground-dwelling mammals in managed forests in western Washington, USA. Over three summers (one pretreatment and two posttreatment), we trapped 19 mammalian species along 23 streams in the northern Coast Range. We compared faunal communities in...

The Planetary Terrestrial Analogues Library (PTAL)

NASA Astrophysics Data System (ADS)

Werner, S. C.; Dypvik, H.; Poulet, F.; Rull Perez, F.; Bibring, J.-P.; Bultel, B.; Casanova Roque, C.; Carter, J.; Cousin, A.; Guzman, A.; Hamm, V.; Hellevang, H.; Lantz, C.; Lopez-Reyes, G.; Manrique, J. A.; Maurice, S.; Medina Garcia, J.; Navarro, R.; Negro, J. I.; Neumann, E. R.; Pilorget, C.; Riu, L.; Sætre, C.; Sansano Caramazana, A.; Sanz Arranz, A.; Sobron Grañón, F.; Veneranda, M.; Viennet, J.-C.; PTAL Team

2018-04-01

The Planetary Terrestrial Analogues Library project aims to build and exploit a spectral data base for the characterisation of the mineralogical and geological evolution of terrestrial planets and small solar system bodies.

Passage of infectious nuclear polyhedrosis virus through the alimentary tracts of two small mammal predators of the gypsy moth, Lymantria dispar

Treesearch

R.A. Lautenschlager; J.D. Podgwaite

1977-01-01

The white-footed mouse, Peromyscus leucopus Rafinesque, and the short-tailed shrew, Blarina brevicauda Say, 2 small mammal predators of the gypsy moth, have demonstrated the ability to pass significant amounts of infectious nuclear polyhedrosis virus (NPV) through their alimentary tracts. Ninety-five percent of the gypsy moth...

Seasonal fluctuations of small mammal and flea communities in a Ugandan plague focus: evidence to implicate Arvicanthis niloticus and Crocidura spp. as key hosts in Yersinia pestis transmission.

PubMed

Moore, Sean M; Monaghan, Andrew; Borchert, Jeff N; Mpanga, Joseph T; Atiku, Linda A; Boegler, Karen A; Montenieri, John; MacMillan, Katherine; Gage, Kenneth L; Eisen, Rebecca J

2015-01-08

The distribution of human plague risk is strongly associated with rainfall in the tropical plague foci of East Africa, but little is known about how the plague bacterium is maintained during periods between outbreaks or whether environmental drivers trigger these outbreaks. We collected small mammals and fleas over a two year period in the West Nile region of Uganda to examine how the ecological community varies seasonally in a region with areas of both high and low risk of human plague cases. Seasonal changes in the small mammal and flea communities were examined along an elevation gradient to determine whether small mammal and flea populations exhibit differences in their response to seasonal fluctuations in precipitation, temperature, and crop harvests in areas within (above 1300 m) and outside (below 1300 m) of a model-defined plague focus. The abundance of two potential enzootic host species (Arvicanthis niloticus and Crocidura spp.) increased during the plague season within the plague focus, but did not show the same increase at lower elevations outside this focus. In contrast, the abundance of the domestic rat population (Rattus rattus) did not show significant seasonal fluctuations regardless of locality. Arvicanthis niloticus abundance was negatively associated with monthly precipitation at a six month lag and positively associated with current monthly temperatures, and Crocidura spp. abundance was positively associated with precipitation at a three month lag and negatively associated with current monthly temperatures. The abundance of A. niloticus and Crocidura spp. were both positively correlated with the harvest of millet and maize. The association between the abundance of several small mammal species and rainfall is consistent with previous models of the timing of human plague cases in relation to precipitation in the West Nile region. The seasonal increase in the abundance of key potential host species within the plague focus, but not outside of

Rickettsia species in fleas collected from small mammals in Slovakia.

PubMed

Špitalská, Eva; Boldiš, Vojtech; Mošanský, Ladislav; Sparagano, Olivier; Stanko, Michal

2015-11-01

Epidemiological and epizootiological studies of Rickettsia felis and other Rickettsia spp. are very important, because their natural cycle has not yet been established completely. In total, 315 fleas (Siphonaptera) of 11 species of Ceratophyllidae, Hystrichopsyllidae and Leptopsyllidae families were tested for the presence of Rickettsia species and Coxiella burnetii with conventional and specific quantitative real-time PCR assays. Fleas were collected from five rodent hosts (Myodes glareolus, Apodemus flavicollis, Apodemus agrarius, Microtus subterraneus, Microtus arvalis) and three shrew species (Sorex araneus, Neomys fodiens, Crocidura suaveolens) captured in Eastern and Southern Slovakia. Overall, Rickettsia spp. was found in 10.8% (34/315) of the tested fleas of Ctenophthalmus agyrtes, Ctenophthalmus solutus, Ctenophthalmus uncinatus and Nosopsyllus fasciatus species. Infected fleas were coming from A. flavicollis, A. agrarius, and M. glareolus captured in Eastern Slovakia. C. burnetii was not found in any fleas. R. felis, Rickettsia helvetica, unidentified Rickettsia, and rickettsial endosymbionts were identified in fleas infesting small mammals in the Košice region, Eastern Slovakia. This study is the first report of R. felis infection in C. solutus male flea collected from A. agrarius in Slovakia.

Heavy-metal concentrations in small mammals from a diffusely polluted floodplain: importance of species- and location-specific characteristics.

PubMed

Wijnhoven, S; Leuven, R S E W; van der Velde, G; Jungheim, G; Koelemij, E I; de Vries, F T; Eijsackers, H J P; Smits, A J M

2007-05-01

The soil of several floodplain areas along large European rivers shows increased levels of heavy metals as a relict from past sedimentation of contaminants. These levels may pose risks of accumulation in food webs and toxicologic effects on flora and fauna. However, for floodplains, data on heavy-metal concentrations in vertebrates are scarce. Moreover, these environments are characterised by periodical flooding cycles influencing ecologic processes and patterns. To investigate whether the suggested differences in accumulation risks for insectivores and carnivores, omnivores, and herbivores are reflected in the actual heavy-metal concentrations in the species, we measured the current levels of Zn, Cu, Pb, and Cd in 199 specimens of 7 small mammal species (voles, mice, and shrews) and in their habitats in a diffusely polluted floodplain. The highest metal concentrations were found in the insectivorous and carnivorous shrew, Sorex araneus. Significant differences between the other shrew species, Crocidura russula, and the vole and mouse species was only found for Cd. The Cu concentration in Clethrionomys glareolus, however, was significantly higher than in several other vole and mouse species. To explain the metal concentrations found in the specimens, we related them to environmental variables at the trapping locations and to certain characteristics of the mammals. Variables taken into account were soil total and CaCl(2)-extractable metal concentrations at the trapping locations; whether locations were flooded or nonflooded; the trapping season; and the life stage; sex; and fresh weight of the specimens. Correlations between body and soil concentrations and location or specimen characteristics were weak. Therefore; we assumed that exposure of small mammals to heavy-metal contamination in floodplains is significantly influenced by exposure time, which is age related, as well as by dispersal and changes in foraging and feeding patterns under influence of periodic

Ongoing unraveling of a continental fauna: decline and extinction of Australian mammals since European settlement.

PubMed

Woinarski, John C Z; Burbidge, Andrew A; Harrison, Peter L

2015-04-14

The highly distinctive and mostly endemic Australian land mammal fauna has suffered an extraordinary rate of extinction (>10% of the 273 endemic terrestrial species) over the last ∼200 y: in comparison, only one native land mammal from continental North America became extinct since European settlement. A further 21% of Australian endemic land mammal species are now assessed to be threatened, indicating that the rate of loss (of one to two extinctions per decade) is likely to continue. Australia's marine mammals have fared better overall, but status assessment for them is seriously impeded by lack of information. Much of the loss of Australian land mammal fauna (particularly in the vast deserts and tropical savannas) has been in areas that are remote from human population centers and recognized as relatively unmodified at global scale. In contrast to general patterns of extinction on other continents where the main cause is habitat loss, hunting, and impacts of human development, particularly in areas of high and increasing human population pressures, the loss of Australian land mammals is most likely due primarily to predation by introduced species, particularly the feral cat, Felis catus, and European red fox, Vulpes vulpes, and changed fire regimes.

Feeding success of Lutzomyia evansi (Diptera: Psychodidae) experimentally exposed to small mammal hosts in an endemic focus of Leishmania chagasi in northern Colombia.

PubMed

Adler, Gregory H; Becerra, María Teresa; Travi, Bruno L

2003-12-01

Lutzomyia evansi is the vector of Leishmania chagasi in northern Colombia. Differences in feeding success were revealed, when this phlebotomine sand fly was fed on five species of small mammal hosts from an endemic focus of visceral leishmaniasis. In each trial, 50 female sand flies were provided access to similar-sized depilated areas of the hind foot of each of 44 individual mammals and allowed to feed for 30 minutes. The number of engorged sand flies was counted at the end of each trial and compared among host species by analysis of variance and Tukey's multiple comparisons test. Sand flies fed least successfully on Sciurus granatensis, a common squirrel in the endemic area. It has not been found infected with L. chagasi. Intermediate numbers of sand flies engorged on Heteromys anomalus and Zygodontomys brevicauda, but these two mammals have not been found infected with L. chagasi and are not expected to be important in transmission. Sand flies fed most successfully on Didelphis marsupialis and Proechimys canicollis. These are the two most abundant mammals in the endemic area and frequently are infected. Results provided further evidence that these two species are the wild mammals with the greatest impact on transmission of L. chagasi in northern Colombia.

Into the dark: patterns of middle ear adaptations in subterranean eulipotyphlan mammals

NASA Astrophysics Data System (ADS)

Koyabu, Daisuke; Hosojima, Misato; Endo, Hideki

2017-09-01

Evolution of the middle ear ossicles was a key innovation for mammals, enhancing the transmission of airborne sound. Radiation into various habitats from a terrestrial environment resulted in diversification of the auditory mechanisms among mammals. However, due to the paucity of phylogenetically controlled investigations, how middle ear traits have diversified with functional specialization remains unclear. In order to identify the respective patterns for various lifestyles and to gain insights into fossil forms, we employed a high-resolution tomography technique and compared the middle ear morphology of eulipotyphlan species (moles, shrews and hedgehogs), a group that has radiated into various environments, such as terrestrial, aquatic and subterranean habitats. Three-dimensional geometric morphometric analysis was conducted within a phylogenetically controlled framework. Quantitative shapes were found to strongly reflect the degree of subterranean lifestyle and weakly involve phylogeny. Our analyses demonstrate that subterranean adaptation should include a relatively shorter anterior process of the malleus, an enlarged incus, an enlarged stapes footplate and a reduction of the orbicular apophysis. These traits arguably allow improving low-frequency sound transmission at low frequencies and inhibiting the low-frequency noise which disturbs the subterranean animals in hearing airborne sounds.

Morphometric variations of laelapine mite (Acari: Mesostigmata) populations infesting small mammals (Mammalia) in Brazil.

PubMed

Martins-Hatano, F; Gettinger, D; Manhães, M L; Bergallo, H G

2012-08-01

The goal of this study was to evaluate the morphometric variation of laelapine populations (Acari, Mesostigmata) associated with neotropical oryzomyine rodents at different geographic localities in Brazil. Three nominal mite species were selected for study, all infesting the pelage of small mammals at different localities in Rio de Janeiro, Espírito Santo, Bahia, and the Federal District, Brazil. To analyse morphometric characteristics, thirty-seven morphological characters distributed across the whole body of each specimen were measured. We use the Analysis of Principal Components, extracting the three first axes and projecting each mite in these axes. Major species level changes in the taxonomy of the host mammals allows an independent examination of morphometric variation of mites infesting a set of distinctly different host species at different geographic localities. Gigantolaelaps vitzthumi and Laelaps differens are associated with oryzomyine rodents of the genus Cerradomys, and consistently showed a tendency to cluster by host phylogeny. Laelaps manguinhosi associated with Nectomys rattus in central Brazil is morphometrically distinct from mites infesting N. squamipes in the coastal restingas of Rio de Janeiro and Espírito Santo. The results obtained here indicate that laelapine mite populations can vary among geographic areas and among phylogenetically related host species. Clearly, the study of these mites at the population level can be an important tool for clarifying the taxonomy of both mites and hosts.

Farewell to life on land - thoracic strength as a new indicator to determine paleoecology in secondary aquatic mammals.

PubMed

Ando, Konami; Fujiwara, Shin-Ichi

2016-12-01

Habitat shifts from land to water have occurred independently in several mammal lineages. However, because we do not know completely about the relationship between skeletal morphology and function, both reliable life reconstructions of each extinct taxon and the timing of those shifts in locomotor strategies are yet to be fully understood. We estimated the strengths of rib cages against vertical compression in 26 extant and four extinct mammal specimens including cetartiodactyls, paenungulates, and carnivorans, representing 11 terrestrial, six semi-aquatic, and nine obligate aquatic taxa. Our analyses of extant taxa showed that strengths were high among terrestrial/semi-aquatic mammals, whose rib cages are subjected to vertical compression during the support on land, whereas strengths were low among obligate aquatic mammals, whose rib cages are not subjected to antigravity force in the water. We therefore propose rib strength as a new index to estimate the ability of an animal to be supported on land while being supported by either the forelimbs or thoracic region. According to our analyses of extinct taxa, this ability to be supported on land was rejected for a basal cetacean (Cetartiodactyla: Ambulocetus) and two desmostylians (Paenungulata: Paleoparadoxia and Neoparadoxia). However, this ability was not rejected for one desmostylian species (Desmostylus). Further study of the ribs of extant/extinct semi-aquatic taxa may help in understanding the ecological shifts in these groups. © 2016 Anatomical Society.

An annotated catalogue of the gamasid mites associated with small mammals in Asiatic Russia. The family Laelapidae s. str. (Acari: Mesostigmata: Gamasina).

PubMed

Vinarski, Maxim V; Korallo-Vinarskaya, Natalia P

2016-05-16

Twenty-nine species of mites of the family Laelapidae s. str. have been recorded as associated with small mammals (rodents, insectivores) in Asiatic Russia (Siberia and the Russian Far East). These species belong to two subfamilies (Laelapinae, Myonyssinae) and six genera: Androlaelaps Berlese, 1903, Dipolaelaps Zemskaya & Piontkovskaya, 1960, Laelaps C.L. Koch, 1836, Hyperlaelaps Zakhvatkin, 1948, Myonyssus Tiraboschi, 1904, Oryctolaelaps Lange, 1955. A list of the species, with data on synonymy, geographic ranges, and relationships with mammal hosts is provided. Some considerations concerning patterns of distribution of the parasitic Laelaptidae of Asiatic Russia are presented as well as their classifications from the point of view of known host association records.

Conservation priorities for mammals in megadiverse Mexico: the efficiency of reserve networks.

PubMed

Ceballos, Gerardo

2007-03-01

A major goal of conservation biologists is to identify critical areas for the conservation of biological diversity and then strategically include them in an efficient system of reserves. In general, however, reserve networks have been selected for different objectives, and most countries lack an evaluation of their reserves' ability to represent a percentage of the national diversity. This paper evaluates the effectiveness of a network of reserves to represent the species of mammals in Mexico. The focus of the analyses is on species and site level, evaluating the representation of all terrestrial mammals in the 30 most important reserves. The representation of all species, endemic species, endangered species, and species with restricted distributions in the reserves was assessed and compared. Endemic or endangered species with restricted distributions were expected to be less represented in reserves than were widespread species. The most important reserves for the conservation of mammals were determined with the use of complementarity analyses. Priority sites for the representation of all the species currently absent from the reserve network were then selected. The results have broad applications for conservation. First, 82% of the mammal species from Mexico were represented in the reserve network, which covers a small portion (3.8%) of the country. Second, this percentage is certainly larger as several reserves were not evaluated due to a lack of data. A priority for a national conservation strategy could be to conduct biological surveys in those reserves lacking inventories to evaluate their contribution to conservation. Third, in spite of its demonstrated value, Mexico's reserve network can be improved by designating complementary areas. Additional priority sites, where reserves are required to represent most gap species in the network, were identified. Finally, it is clear that this reserve network has limitations for maintaining biodiversity and ecosystem

Climate and landscape in Italy during Late Epigravettian. The Late Glacial small mammal sequence of Riparo Tagliente (Stallavena di Grezzana, Verona, Italy)

NASA Astrophysics Data System (ADS)

Berto, Claudio; Luzi, Elisa; Canini, Guido Montanari; Guerreschi, Antonio; Fontana, Federica

2018-03-01

The site of Riparo Tagliente (north-eastern Italy) contains one of the main Upper Pleistocene archaeological sequences of south-western Europe. It also represents a key site for the study of human adaptation to Late Glacial environmental changes in the southern Alpine area. These climatic and environmental conditions are here reconstructed based on small mammal assemblages, using the Bioclimatic model and Habitat Weighting methods. Climate proxies indicate a rise in temperature during the transition between HE1 and the Bølling-Allerød interstadial, while the landscape surrounding the shelter was still dominated by open grasslands. By comparing the data obtained from Riparo Tagliente with other coeval small mammal faunas from the Italian Peninsula and Europe we contribute to the reconstruction of the processes of faunal renewal registered during the Late Glacial across the continent and of the climatic and environmental context in which the Late Epigravettian hunter-gatherer groups lived.

Ontogenetic niche shifts in dinosaurs influenced size, diversity and extinction in terrestrial vertebrates.

PubMed

Codron, Daryl; Carbone, Chris; Müller, Dennis W H; Clauss, Marcus

2012-08-23

Given the physiological limits to egg size, large-bodied non-avian dinosaurs experienced some of the most extreme shifts in size during postnatal ontogeny found in terrestrial vertebrate systems. In contrast, mammals--the other dominant vertebrate group since the Mesozoic--have less complex ontogenies. Here, we develop a model that quantifies the impact of size-specific interspecies competition on abundances of differently sized dinosaurs and mammals, taking into account the extended niche breadth realized during ontogeny among large oviparous species. Our model predicts low diversity at intermediate size classes (between approx. 1 and 1000 kg), consistent with observed diversity distributions of dinosaurs, and of Mesozoic land vertebrates in general. It also provides a mechanism--based on an understanding of different ecological and evolutionary constraints across vertebrate groups--that explains how mammals and birds, but not dinosaurs, were able to persist beyond the Cretaceous-Tertiary (K-T) boundary, and how post-K-T mammals were able to diversify into larger size categories.

Seasonal Habitat Distribution Of Swamp Rabbits, White-Tailed Deer, and Small Mammals in Old Growth and Managed Bottomland Hardwood Forests

Treesearch

Winston P. Smith; Patrick A. Zollner

2001-01-01

We studied swamp rabbits, white-tailed deer, and small mammals in an old-growth and adjacent second-growth and young-growth bottomland hardwood forest stands in southern Arkansas, August 1991 – February 1993. Based on average home range size and degree of overlap, minimum and maximum density estimates of swamp rabbits were 31 per km2 (no overlap)...

Drivers and hotspots of extinction risk in marine mammals.

PubMed

Davidson, Ana D; Boyer, Alison G; Kim, Hwahwan; Pompa-Mansilla, Sandra; Hamilton, Marcus J; Costa, Daniel P; Ceballos, Gerardo; Brown, James H

2012-02-28

The world's oceans are undergoing profound changes as a result of human activities. However, the consequences of escalating human impacts on marine mammal biodiversity remain poorly understood. The International Union for the Conservation of Nature (IUCN) identifies 25% of marine mammals as at risk of extinction, but the conservation status of nearly 40% of marine mammals remains unknown due to insufficient data. Predictive models of extinction risk are crucial to informing present and future conservation needs, yet such models have not been developed for marine mammals. In this paper, we: (i) used powerful machine-learning and spatial-modeling approaches to understand the intrinsic and extrinsic drivers of marine mammal extinction risk; (ii) used this information to predict risk across all marine mammals, including IUCN "Data Deficient" species; and (iii) conducted a spatially explicit assessment of these results to understand how risk is distributed across the world's oceans. Rate of offspring production was the most important predictor of risk. Additional predictors included taxonomic group, small geographic range area, and small social group size. Although the interaction of both intrinsic and extrinsic variables was important in predicting risk, overall, intrinsic traits were more important than extrinsic variables. In addition to the 32 species already on the IUCN Red List, our model identified 15 more species, suggesting that 37% of all marine mammals are at risk of extinction. Most at-risk species occur in coastal areas and in productive regions of the high seas. We identify 13 global hotspots of risk and show how they overlap with human impacts and Marine Protected Areas.

Terrestrial Ecology Guide.

ERIC Educational Resources Information Center

Morrison, James W., Ed.; Hall, James A., Ed.

This collection of study units focuses on the study of the ecology of land habitats. Considered are such topics as map reading, field techniques, forest ecosystem, birds, insects, small mammals, soils, plant ecology, preparation of terrariums, air pollution, photography, and essentials of an environmental studies program. Each unit contains…

A radiographic method to estimate lung volume and its use in small mammals.

PubMed

Canals, Mauricio; Olivares, Ricardo; Rosenmann, Mario

2005-01-01

In this paper we develop a method to estimate lung volume using chest x-rays of small mammals. We applied this method to assess the lung volume of several rodents. We showed that a good estimator of the lung volume is: V*L = 0.496 x VRX approximately equal to 1/2 x VRX, where VRX is a measurement obtained from the x-ray that represents the volume of a rectangular box containing the lungs and mediastinum organs. The proposed formula may be interpreted as the volume of an ellipsoid formed by both lungs joined at their bases. When that relationship was used to estimate lung volume, values similar to those expected from allometric relationship were found in four rodents. In two others, M. musculus and R. norvegicus, lung volume was similar to reported data, although values were lower than expected.

Hantavirus surveillance and genetic diversity targeting small mammals at Camp Humphreys, a US military installation and new expansion site, Republic of Korea

PubMed Central

Klein, Terry A.; Chong, Sung-Tae; Nunn, Peter V.; Kim, Jeong-Ah; Lee, Seung-Ho; No, Jin Sun; Song, Jin-Won

2017-01-01

Small mammal surveillance was conducted (2008–2010, 2012) at Camp (Cp) Humphreys, a US Army installation and new expansion site, Republic of Korea (ROK), to identify hemorrhagic fever with renal syndrome health threats to US military/civilian populations during its ongoing expansion phase. Small mammals were collected using Sherman live capture traps and transported to Korea University where they were euthanized, tissues removed, and assayed to determine hantavirus IgG antibody-positive and hantavirus-positive rates by RT-PCR. A total of 2,364 small mammals were captured over 11,300 trap nights (capture rate = 20.92%). Apodemus agrarius was the most commonly collected (76.65%), with capture rates of 9.62% and 21.70% for Cp Humphreys and the expansion site, respectively. Overall, Hantaan virus (HTNV) IgG antibody-positive (Ab+) rate for A. agrarius was 2.15% (39/1,812). A total of 5.43% (10/184) Crocidura lasiura, 0.79% (2/254) Microtus fortis and 2.44% (1/41) Micromys minutus were serologically IgG Ab+ for hantaviruses. HTNV-specific RT-PCR demonstrated that 28.2% (11/39) HTNV Ab+ A. agrarius harbored the 328-nt sequence of the GC glycoprotein-encoding M segment of HTNV. Among them, the whole genome sequences of 3 HTNV strains were obtained by conventional RT-PCR and Rapid Amplification cDNA Ends PCR. Phylogenetic analyses of the HTNV strains from Cp Humphreys and the expansion site, Pyeongtaek, show a greater diversity of rodent-borne hantaviruses compared to HTNV previously identified in Gyeonggi province of the ROK. Thus, this study provides significant insights for raising HFRS threat awareness, analysis, and risk reduction strategies in southern Gyeonggi province. PMID:28448595

Resolving the relationships of Paleocene placental mammals.

PubMed

Halliday, Thomas J D; Upchurch, Paul; Goswami, Anjali

2017-02-01

The 'Age of Mammals' began in the Paleocene epoch, the 10 million year interval immediately following the Cretaceous-Palaeogene mass extinction. The apparently rapid shift in mammalian ecomorphs from small, largely insectivorous forms to many small-to-large-bodied, diverse taxa has driven a hypothesis that the end-Cretaceous heralded an adaptive radiation in placental mammal evolution. However, the affinities of most Paleocene mammals have remained unresolved, despite significant advances in understanding the relationships of the extant orders, hindering efforts to reconstruct robustly the origin and early evolution of placental mammals. Here we present the largest cladistic analysis of Paleocene placentals to date, from a data matrix including 177 taxa (130 of which are Palaeogene) and 680 morphological characters. We improve the resolution of the relationships of several enigmatic Paleocene clades, including families of 'condylarths'. Protungulatum is resolved as a stem eutherian, meaning that no crown-placental mammal unambiguously pre-dates the Cretaceous-Palaeogene boundary. Our results support an Atlantogenata-Boreoeutheria split at the root of crown Placentalia, the presence of phenacodontids as closest relatives of Perissodactyla, the validity of Euungulata, and the placement of Arctocyonidae close to Carnivora. Periptychidae and Pantodonta are resolved as sister taxa, Leptictida and Cimolestidae are found to be stem eutherians, and Hyopsodontidae is highly polyphyletic. The inclusion of Paleocene taxa in a placental phylogeny alters interpretations of relationships and key events in mammalian evolutionary history. Paleocene mammals are an essential source of data for understanding fully the biotic dynamics associated with the end-Cretaceous mass extinction. The relationships presented here mark a critical first step towards accurate reconstruction of this important interval in the evolution of the modern fauna. © 2015 The Authors. Biological Reviews

Juvenile frogs compensate for small metamorph size with terrestrial growth: Overcoming the effects of larval density and insecticide exposure

USGS Publications Warehouse

Boone, M.D.

2005-01-01

I reared four species of anurans (Rana sphenocephala [Southern Leopard Frog], Rana blairi [Plains Leopard Frog], Rana clamitans [Green Frog], and Bufo woodhousii [Woodhouse's Toad]) for seven to 12 months in small, outdoor terrestrial enclosures (1 x 2 m) to examine the consequences of larval competition (via density) and contaminant exposure (via the insecticide carbaryl). I added six Rana clamitans, eight Rana sphenocephala, eight Rana blairi, and 10 Bufo woodhousii to terrestrial enclosures shortly after metamorphosis and recaptured them during the following spring. All anurans from low-density ponds were significantly larger than those from high-density ponds, but these size differences did not significantly affect survival to or size at spring emergence. However, R. sphenocephala, R. blairi, and R. clamitans that survived to spring had been larger at metamorphosis on average than those that did not survive; in contrast, B. woodhousii that survived the winter were smaller at metamorphosis on average than those that did not survive. Carbaryl exposure affected mass at metamorphosis of R. clamitans and B. woodhousii that were added to enclosures, but this difference disappeared or did not increase by spring emergence. Overall, exposure to carbaryl during the larval period did not have any apparent effects on survival or growth during the terrestrial phase. In my study, anurans were able to offset small size at metamorphosis with terrestrial growth, although there was a trend of reduced overwinter survival for ranid species that metamorphosed at a smaller size. Copyright 2005 Society for the Study of Amphibians and Reptiles.

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

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

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.

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

Characteristics and Propagation of Airgun Pulses in Shallow Water with Implications for Effects on Small Marine Mammals.

PubMed

Hermannsen, Line; Tougaard, Jakob; Beedholm, Kristian; Nabe-Nielsen, Jacob; Madsen, Peter Teglberg

2015-01-01

Airguns used in seismic surveys are among the most prevalent and powerful anthropogenic noise sources in marine habitats. They are designed to produce most energy below 100 Hz, but the pulses have also been reported to contain medium-to-high frequency components with the potential to affect small marine mammals, which have their best hearing sensitivity at higher frequencies. In shallow water environments, inhabited by many of such species, the impact of airgun noise may be particularly challenging to assess due to complex propagation conditions. To alleviate the current lack of knowledge on the characteristics and propagation of airgun pulses in shallow water with implications for effects on small marine mammals, we recorded pulses from a single airgun with three operating volumes (10 in3, 25 in3 and 40 in3) at six ranges (6, 120, 200, 400, 800 and 1300 m) in a uniform shallow water habitat using two calibrated Reson 4014 hydrophones and four DSG-Ocean acoustic data recorders. We show that airgun pulses in this shallow habitat propagated out to 1300 meters in a way that can be approximated by a 18log(r) geometric transmission loss model, but with a high pass filter effect from the shallow water depth. Source levels were back-calculated to 192 dB re µPa2s (sound exposure level) and 200 dB re 1 µPa dB Leq-fast (rms over 125 ms duration), and the pulses contained substantial energy up to 10 kHz, even at the furthest recording station at 1300 meters. We conclude that the risk of causing hearing damage when using single airguns in shallow waters is small for both pinnipeds and porpoises. However, there is substantial potential for significant behavioral responses out to several km from the airgun, well beyond the commonly used shut-down zone of 500 meters.

Characteristics and Propagation of Airgun Pulses in Shallow Water with Implications for Effects on Small Marine Mammals

PubMed Central

Hermannsen, Line; Tougaard, Jakob; Beedholm, Kristian; Nabe-Nielsen, Jacob; Madsen, Peter Teglberg

2015-01-01

Airguns used in seismic surveys are among the most prevalent and powerful anthropogenic noise sources in marine habitats. They are designed to produce most energy below 100 Hz, but the pulses have also been reported to contain medium-to-high frequency components with the potential to affect small marine mammals, which have their best hearing sensitivity at higher frequencies. In shallow water environments, inhabited by many of such species, the impact of airgun noise may be particularly challenging to assess due to complex propagation conditions. To alleviate the current lack of knowledge on the characteristics and propagation of airgun pulses in shallow water with implications for effects on small marine mammals, we recorded pulses from a single airgun with three operating volumes (10 in3, 25 in3 and 40 in3) at six ranges (6, 120, 200, 400, 800 and 1300 m) in a uniform shallow water habitat using two calibrated Reson 4014 hydrophones and four DSG-Ocean acoustic data recorders. We show that airgun pulses in this shallow habitat propagated out to 1300 meters in a way that can be approximated by a 18log(r) geometric transmission loss model, but with a high pass filter effect from the shallow water depth. Source levels were back-calculated to 192 dB re µPa2s (sound exposure level) and 200 dB re 1 µPa dB Leq-fast (rms over 125 ms duration), and the pulses contained substantial energy up to 10 kHz, even at the furthest recording station at 1300 meters. We conclude that the risk of causing hearing damage when using single airguns in shallow waters is small for both pinnipeds and porpoises. However, there is substantial potential for significant behavioral responses out to several km from the airgun, well beyond the commonly used shut-down zone of 500 meters. PMID:26214849

Ongoing unraveling of a continental fauna: Decline and extinction of Australian mammals since European settlement

PubMed Central

Woinarski, John C. Z.; Burbidge, Andrew A.; Harrison, Peter L.

2015-01-01

The highly distinctive and mostly endemic Australian land mammal fauna has suffered an extraordinary rate of extinction (>10% of the 273 endemic terrestrial species) over the last ∼200 y: in comparison, only one native land mammal from continental North America became extinct since European settlement. A further 21% of Australian endemic land mammal species are now assessed to be threatened, indicating that the rate of loss (of one to two extinctions per decade) is likely to continue. Australia’s marine mammals have fared better overall, but status assessment for them is seriously impeded by lack of information. Much of the loss of Australian land mammal fauna (particularly in the vast deserts and tropical savannas) has been in areas that are remote from human population centers and recognized as relatively unmodified at global scale. In contrast to general patterns of extinction on other continents where the main cause is habitat loss, hunting, and impacts of human development, particularly in areas of high and increasing human population pressures, the loss of Australian land mammals is most likely due primarily to predation by introduced species, particularly the feral cat, Felis catus, and European red fox, Vulpes vulpes, and changed fire regimes. PMID:25675493

Terrestrial flora and fauna in the vicinity of the Delmarva Power and Light station and proposed expansion site. Special report 77

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Deusen, M.; Otto, R.G.

1979-12-01

The results of field surveys of the terrestrial vegetation, birds and mammals in the vicinity of the Delmarva Power and Light Company Vienna Steam Electric Station and proposed expansion area in Dorchester County, Maryland are presented. Four major habitats were identified: forest, oldfield, marsh and cultivated land. Qualitative surveys of flora and fauna were conducted to determine species present. Commercially important waterfowl, upland game birds and mammals and furbearers are discussed. The status of endangered or threatened plants (seaside alder), birds (bald eagle) and mammals (Delmarva fox squirrel) on the site is evaluated.

Terrestrial flora and fauna in the vicinity of the Delmarva power and light station and proposed expansion site. Special report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Deusen, M.; Otto, R.G.

1980-04-01

The results of field surveys of the terrestrial vegetation, birds and mammals in the vicinity of the Delmarva Power and Light Company Vienna Steam Electric Station and proposed expansion area in Dorchester County, Maryland are presented. Four major habitats were identified: forest, oldfield, marsh and cultivated land. Qualitative surveys of flora and fauna were conducted to determine species present. Commercially important waterfowl, upland game birds and mammals and furbearers are discussed.

Is gastrointestinal microbiota relevant for endogenous mercury methylation in terrestrial animals?

PubMed

Martín-Doimeadios, R C Rodríguez; Mateo, R; Jiménez-Moreno, M

2017-01-01

The active role of gastrointestinal microbiota in mercury (Hg) methylation has been investigated in different terrestrial organisms from insects or annelids to rats and mammals, including the human beings. Some findings reveal the animal digestive tracts as new potential niches for Hg methylation especially in terrestrial invertebrates. However, contradictory results have been reported so far and there is still a long way to fully understand how important the MeHg production in this habitat could be, as well as its implications on the toxicity and biomagnification of MeHg within terrestrial food chains. It is important to know what has been studied in the past and discuss the previous results according to the new perspectives opened in this field. Therefore, the aim of this work is to review the present state of knowledge about the potential capability of gastrointestinal microbiota in Hg methylation with special emphasis in terrestrial animals and to propose new approaches profiting the new and powerful molecular and analytical tools. Copyright © 2016 Elsevier Inc. All rights reserved.

Recovery Trends in Marine Mammal Populations

PubMed Central

Magera, Anna M.; Mills Flemming, Joanna E.; Kaschner, Kristin; Christensen, Line B.; Lotze, Heike K.

2013-01-01

study of populations with major data gaps, including offshore small cetaceans, cryptic species, and marine mammals in low latitudes and developing nations, is needed to better understand the status of marine mammal populations worldwide. PMID:24205025

Phenotypic and molecular characterisation of Brucella isolates from marine mammals

PubMed Central

Dawson, Claire E; Stubberfield, Emma J; Perrett, Lorraine L; King, Amanda C; Whatmore, Adrian M; Bashiruddin, John B; Stack, Judy A; MacMillan, Alastair P

2008-01-01

Background Bacteria of the genus Brucella are the causative organisms of brucellosis in animals and man. Previous characterisation of Brucella strains originating from marine mammals showed them to be distinct from the terrestrial species and likely to comprise one or more new taxa. Recently two new species comprising Brucella isolates from marine mammals, B. pinnipedialis and B. ceti, were validly published. Here we report on an extensive study of the molecular and phenotypic characteristics of marine mammal Brucella isolates and on how these characteristics relate to the newly described species. Results In this study, 102 isolates of Brucella originating from eleven species of marine mammals were characterised. Results obtained by analysis using the Infrequent Restriction Site (IRS)-Derivative PCR, PCR-RFLP of outer membrane protein genes (omp) and IS711 fingerprint profiles showed good consistency with isolates originating from cetaceans, corresponding to B. ceti, falling into two clusters. These correspond to isolates with either dolphins or porpoises as their preferred host. Isolates originating predominantly from seals, and corresponding to B. pinnipedialis, cluster separately on the basis of IS711 fingerprinting and other molecular approaches and can be further subdivided, with isolates from hooded seals comprising a distinct group. There was little correlation between phenotypic characteristics used in classical Brucella biotyping and these groups. Conclusion Molecular approaches are clearly valuable in the division of marine mammal Brucella into subtypes that correlate with apparent ecological divisions, whereas conventional bioyping is of less value. The data presented here confirm that there are significant subtypes within the newly described marine mammal Brucella species and add to a body of evidence that could lead to the recognition of additional species or sub-species within this group. PMID:19091076

Effects of habitat fragmentation on wild mammal infection by Trypanosoma cruzi.

PubMed

Vaz, V C; D'Andrea, P S; Jansen, A M

2007-11-01

Expansion of human activities frequently results in habitat fragmentation, a phenomenon that has been widely recognized in the last decades as one of the major threats to world's biodiversity. The transformation of a continuous forest into a fragmented area results in a hyper-dynamic landscape with unpredictable consequences to overall ecosystem health. The effect of the fragmentation process on Trypanosoma cruzi infection among small wild mammals was studied in an Atlantic Rain Forest landscape. Comparing continous forest to fragmented habitat, marsupials were less abundant than rodents in the continuous landscape. An overall decrease in small wild mammal richness was observed in the smaller fragments. An anti-T. cruzi seroprevalence of 18% (82/440) was deteced by immunofluorescence assay. Moreover, this seroprevalence was higher in the fragmented habitat than in the continuous forest. According to the collected data, 3 main factors seem to modulate infection by T. cruzi in small wild mammals: (i) habitat fragmentation; (ii) biodiversity loss; (iii) increase of marsupial abundance in mammal communities. Furthermore, an extremely mild controlled infection by T. cruzi was detected since no patent parasitaemia could be detected in fresh blood samples, and no parasites were isolated by haemoculture.

Responses of wild small mammals to arsenic pollution at a partially remediated mining site in Southern France.

PubMed

Drouhot, Séverine; Raoul, Francis; Crini, Nadia; Tougard, Christelle; Prudent, Anne-Sophie; Druart, Coline; Rieffel, Dominique; Lambert, Jean-Claude; Tête, Nicolas; Giraudoux, Patrick; Scheifler, Renaud

2014-02-01

Partial remediation actions at a former gold mine in Southern France led to a mosaic of contaminated and rehabilitated zones. In this study, the distribution of arsenic and its potential adverse effects on small mammals were investigated. The effectiveness of remediation for reducing the transfer of this element into wildlife was also discussed. Arsenic levels were measured in the soil and in the stomach contents, livers, kidneys, and lungs of four small mammal species (the wood mouse (Apodemus sylvaticus), the Algerian mouse (Mus spretus), the common vole (Microtus arvalis), and the greater white-toothed shrew (Crocidura russula)). The animals were caught at the former extraction site, in zones with three different levels of remediation treatments, and at a control site. Arsenic concentrations in the soil were highly spatially heterogeneous (ranging from 29 to 18,900 μg g(-1)). Despite the decrease in arsenic concentrations in the remediated soils, both wood mice and Algerian mice experienced higher oral exposure to arsenic in remediated zones than in the control area. The accumulated arsenic in their organs showed higher intra-zonal variability than the arsenic distribution in the soil, suggesting that, in addition to remediation processes, other variables can help explain arsenic transfer to wildlife, such as the habitat and diet preferences of the animals or their mobility. A weak but significant correlation between arsenic concentration and body condition was observed, and weak relationships between the liver/kidney/lung mass and arsenic levels were also detected, suggesting possible histological alterations. © 2013.

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

... of Marine Mammals Incidental to Specified Activities; Dumbarton Bridge Seismic Retrofit Project... pile driving associated with the Dumbarton Bridge Seismic Retrofit Project. DATES: Effective August 15... request from Caltrans to harass marine mammals incidental to the Dumbarton Bridge Seismic Retrofit Project...

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

Post-fire recovery of torpor and activity patterns of a small mammal.

PubMed

Stawski, Clare; Hume, Taylor; Körtner, Gerhard; Currie, Shannon E; Nowack, Julia; Geiser, Fritz

2017-05-01

To cope with the post-fire challenges of decreased availability of food and shelter, brown antechinus ( Antechinus stuartii ), a small marsupial mammal, increase the use of energy-conserving torpor and reduce activity. However, it is not known how long it takes for animals to resume pre-fire torpor and activity patterns during the recovery of burnt habitat. Therefore, we tested the hypothesis that antechinus will adjust torpor use and activity after a fire depending on vegetation recovery. We simultaneously quantified torpor and activity patterns for female antechinus from three adjacent areas: (i) the area of a management burn 1 year post-fire, (ii) an area that was burned 2 years prior, and (iii) a control area. In comparison to shortly after the management burn, antechinus in all three groups displayed less frequent and less pronounced torpor while being more active. We provide the first evidence that only 1 year post-fire antechinus resume pre-fire torpor and activity patterns, probably in response to the return of herbaceous ground cover and foraging opportunities. © 2017 The Author(s).

Middle to Late Pleistocene environmental and climatic reconstruction of the human occurrence at Grotta Maggiore di San Bernardino (Vicenza, Italy) through the small-mammal assemblage

NASA Astrophysics Data System (ADS)

López-García, Juan Manuel; Luzi, Elisa; Peresani, Marco

2017-07-01

Grotta Maggiore di San Bernardino, located at an altitude of 135 m a.s.l. in the Berici Hills in northeastern Italy, is an archaeological site with a discontinuous sedimentary sequence dating from Marine Isotope Stage 7 (MIS 7) to MIS 3. In this paper we present for the first time a palaeoenvironmental and palaeoclimatic reconstruction of the sequence based on small-mammal (insectivore, bat and rodent) assemblages. Coupled with biochronological data and absolute dating together with previous studies on large mammals, birds and other studies on small mammals and pollen from comparable time-spans in Italy, the results enable us clearly to identify distinct climatic periods: the end of MIS 7 (7c to 7a) in units VIII-VII, MIS 5d in unit V, and probably MIS 5b in unit IV and an indeterminate MIS 3 interstadial in units III-II. Finally, the study shows that the early Middle Palaeolithic human occupation in Italy occurs during mild and temperate sub-stages of MIS 7 and that human groups with the same techno-cultural background (Mousterian) were well adapted to the changing environmental and climatic conditions of the Middle to Late Pleistocene in this part of southern Europe.

A new perspective on adiposity in a naturally obese mammal

NASA Technical Reports Server (NTRS)

Ortiz, R. M.; Noren, D. P.; Litz, B.; Ortiz, C. L.

2001-01-01

Many mammals seasonally reduce body fat due to inherent periods of fasting, which is associated with decreased leptin concentrations. However, no data exist on the correlation between fat mass (FM) and circulating leptin in marine mammals, which have evolved large fat stores as part of their adaptation to periods of prolonged fasting. Therefore, FM was estimated (by tritiated water dilution), and serum leptin and cortisol were measured in 40 northern elephant seal (Mirounga angustirostris) pups early (<1 wk postweaning) and late (6-8 wk postweaning) during their natural, postweaning fast. Body mass (BM) and FM were reduced late; however, percent FM (early: 43.9 +/- 0.5, late: 45.5 +/- 0.5%) and leptin [early: 2.9 +/- 0.1 ng/ml human equivalents (HE), late: 3.0 +/- 0.1 ng/ml HE] did not change. Cortisol increased between early (9.2 +/- 0.5 microg/dl) and late (16.3 +/- 0.9 microg/dl) periods and was significantly and negatively correlated with BM (r = 0.426; P < 0.0001) and FM (r = 0.328; P = 0.003). FM and percent FM were not correlated (P > 0.10) with leptin at either period. The present study suggests that these naturally obese mammals appear to possess a novel cascade for regulating body fat that includes cortisol. The lack of a correlation between leptin and FM may reflect the different functions of fat between terrestrial and marine mammals.

Paleoecological implications of Alaskan terrestrial vertebrate fauna in latest Cretaceous time at high paleolatitudes

NASA Astrophysics Data System (ADS)

Clemens, William A.; Gayle Nelms, L.

1993-06-01

The latest Cretaceous cool temperate environment of the Alaskan North Slope included dinosaurs (some species represented by both juveniles and adults) and mammals, all probably endothermic, and freshwater fish among its terrestrial vertebrate fauna. No traces have been found of amphibians or nondinosaurian reptiles, ectothermic vertebrates that are abundantly represented in approximately contemporaneous faunas of North American middle paleolatitudes. A geologically brief period of intense cold and darkness has been hypothesized as the primary cause of terminal Cretaceous extinctions. However, the extinction of the lineages of Alaskan dinosaurs and mammals, in contrast to the survival of most lineages of amphibians and nondinosaurian reptiles into the Tertiary, contradicts this hypothesis.

Trypanosomes of Australian mammals: A review

PubMed Central

Thompson, Craig K.; Godfrey, Stephanie S.; Thompson, R.C. Andrew

2014-01-01

Approximately 306 species of terrestrial and arboreal mammals are known to have inhabited the mainland and coastal islands of Australia at the time of European settlement in 1788. The exotic Trypanosoma lewisi was the first mammalian trypanosome identified in Australia in 1888, while the first native species, Trypanosoma pteropi, was taxonomically described in 1913. Since these discoveries, about 22% of the indigenous mammalian fauna have been examined during the surveillance of trypanosome biodiversity in Australia, including 46 species of marsupials, 9 rodents, 9 bats and both monotremes. Of those mammals examined, trypanosomes have been identified from 28 host species, with eight native species of Trypanosoma taxonomically described. These native trypanosomes include T. pteropi, Trypanosoma thylacis, Trypanosoma hipposideri, Trypanosoma binneyi, Trypanosoma irwini, Trypanosoma copemani, Trypanosoma gilletti and Trypanosoma vegrandis. Exotic trypanosomes have also been identified from the introduced mammalian fauna of Australia, and include T. lewisi, Trypanosoma melophagium, Trypanosoma theileri, Trypanosoma nabiasi and Trypanosoma evansi. Fortunately, T. evansi was eradicated soon after its introduction and did not establish in Australia. Of these exotic trypanosomes, T. lewisi is the sole representative that has been reported from indigenous Australian mammals; morphological forms were recorded from two indigenous species of rodents (Hydromys chrysogaster and Rattus fuscipes). Numerous Australian marsupial species are potentially at risk from the native T. copemani, which may be chronically pathogenic, while marsupials, rodents and monotremes appear at risk from exotic species, including T. lewisi, Trypanosoma cruzi and T. evansi. This comprehensive review of trypanosome biodiversity in Australia highlights the negative impact of these parasites upon their mammalian hosts, as well as the threatening biosecurity concerns. PMID:25161902

50 CFR 18.25 - Exempted marine mammals or marine mammal products.

Code of Federal Regulations, 2012 CFR

2012-10-01

... effective date of the foreign law making the taking or sale, as the case may be, of such marine mammals or... mammals or marine mammal products. (a) The provisions of the Act and these regulations shall not apply: (1... marine mammal portion of such product consists solely of a marine mammal taken before such date. (b) The...

50 CFR 18.25 - Exempted marine mammals or marine mammal products.

Code of Federal Regulations, 2013 CFR

2013-10-01

... effective date of the foreign law making the taking or sale, as the case may be, of such marine mammals or... mammals or marine mammal products. (a) The provisions of the Act and these regulations shall not apply: (1... marine mammal portion of such product consists solely of a marine mammal taken before such date. (b) The...

50 CFR 18.25 - Exempted marine mammals or marine mammal products.

Code of Federal Regulations, 2010 CFR

2010-10-01

... effective date of the foreign law making the taking or sale, as the case may be, of such marine mammals or... mammals or marine mammal products. (a) The provisions of the Act and these regulations shall not apply: (1... marine mammal portion of such product consists solely of a marine mammal taken before such date. (b) The...

50 CFR 18.25 - Exempted marine mammals or marine mammal products.

Code of Federal Regulations, 2011 CFR

2011-10-01

... effective date of the foreign law making the taking or sale, as the case may be, of such marine mammals or... mammals or marine mammal products. (a) The provisions of the Act and these regulations shall not apply: (1... marine mammal portion of such product consists solely of a marine mammal taken before such date. (b) The...

50 CFR 18.25 - Exempted marine mammals or marine mammal products.

Code of Federal Regulations, 2014 CFR

2014-10-01

... effective date of the foreign law making the taking or sale, as the case may be, of such marine mammals or... mammals or marine mammal products. (a) The provisions of the Act and these regulations shall not apply: (1... marine mammal portion of such product consists solely of a marine mammal taken before such date. (b) The...

Infection of California sea lions (Zalophus californianus) with terrestrial Brucella spp.

PubMed

Avalos-Téllez, Rosalía; Ramírez-Pfeiffer, Carlos; Hernández-Castro, Rigoberto; Díaz-Aparicio, Efrén; Sánchez-Domínguez, Carlos; Zavala-Norzagaray, Alan; Arellano-Reynoso, Beatriz; Suárez-Güemes, Francisco; Aguirre, A Alonso; Aurioles-Gamboa, David

2014-10-01

Infections with Brucella ceti and pinnipedialis are prevalent in marine mammals worldwide. A total of 22 California sea lions (Zalophus californianus) were examined to determine their exposure to Brucella spp. at San Esteban Island in the Gulf of California, Mexico, in June and July 2011. Although samples of blood, vaginal mucus and milk cultured negative for these bacteria, the application of rose Bengal, agar gel immunodiffusion, PCR and modified fluorescence polarization assays found that five animals (22.7%) had evidence of exposure to Brucella strains. The data also suggested that in two of these five sea lions the strains involved were of terrestrial origin, a novel finding in marine mammals. Further work will be required to validate and determine the epidemiological significance of this finding. Copyright © 2014 Elsevier Ltd. All rights reserved.

78 FR 51147 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-20

... monitoring systems; and (5) exacting funds from TGS to support accelerated mitigation research in this area... (2D) seismic survey program in the Chukchi Sea, Alaska, during the 2013 Arctic open-water season... small numbers of marine mammals incidental to conducting an open-water 2D seismic survey in the Chukchi...

Late Pleistocene and Holocene mammal extinctions on continental Africa

NASA Astrophysics Data System (ADS)

Faith, J. Tyler

2014-01-01

Understanding the cause of late Quaternary mammal extinctions is the subject of intense debate spanning the fields of archeology and paleontology. In the global context, the losses on continental Africa have received little attention and are poorly understood. This study aims to inspire new discussion of African extinctions through a review of the extinct species and the chronology and possible causes of those extinctions. There are at least 24 large mammal (> 5 kg) species known to have disappeared from continental Africa during the late Pleistocene or Holocene, indicating a much greater taxonomic breadth than previously recognized. Among the better sampled taxa, these losses are restricted to the terminal Pleistocene and early Holocene, between 13,000 and 6000 yrs ago. The African extinctions preferentially affected species that are grazers or prefer grasslands. Where good terrestrial paleoenvironmental records are present, extinctions are associated with changes in the availability, productivity, or structure of grassland habitats, suggesting that environmental changes played a decisive role in the losses. In the broader evolutionary context, these extinctions represent recent examples of selective taxonomic winnowing characterized by the loss of grassland specialists and the establishment of large mammal communities composed of more ecologically flexible taxa over the last million years. There is little reason to believe that humans played an important role in African extinctions.

Prevalence of Trypanosoma cruzi infection in dogs and small mammals in Nuevo León, Mexico.

PubMed

Galaviz-Silva, Lucio; Mercado-Hernández, Roberto; Zárate-Ramos, José J; Molina-Garza, Zinnia J

Chagas disease, caused by the protozoan Trypanosoma cruzi, is an important public health concern in areas extending from South America northward into the southern United States of America. Although this hemoflagellate has many wild and domestic mammalians reported as reservoir hosts, studies on this subject are scarce in Nuevo León state, a region located in northeastern Mexico. This cross-sectional study showed that the general prevalence of T. cruzi infection in Nuevo León state was 14.5% (35/241), this percentage matching the ones determined by PCR and traditional diagnostics. Localities and infected mammals did not significantly differ (χ 2 =6.098, p=0.192); however the number of infected animals was highly correlated with mammalian species (p=0.009). Striped skunks (Mephitis mephitis) were found to be the most infected overall (11/34, 32.3%), while dogs (Canis familiaris) had the lowest prevalence. In conclusion, although the prevalence of T. cruzi infection in small mammals was lower in Nuevo León than in other states of Mexico, our results provide new locality records, including striped skunks, opossums (Didelphis marsupialis) and dogs, and extend the recorded area to woodrats (Neotoma micropus). Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Species longevity in North American fossil mammals.

PubMed

Prothero, Donald R

2014-08-01

Species longevity in the fossil record is related to many paleoecological variables and is important to macroevolutionary studies, yet there are very few reliable data on average species durations in Cenozoic fossil mammals. Many of the online databases (such as the Paleobiology Database) use only genera of North American Cenozoic mammals and there are severe problems because key groups (e.g. camels, oreodonts, pronghorns and proboscideans) have no reliable updated taxonomy, with many invalid genera and species and/or many undescribed genera and species. Most of the published datasets yield species duration estimates of approximately 2.3-4.3 Myr for larger mammals, with small mammals tending to have shorter species durations. My own compilation of all the valid species durations in families with updated taxonomy (39 families, containing 431 genera and 998 species, averaging 2.3 species per genus) yields a mean duration of 3.21 Myr for larger mammals. This breaks down to 4.10-4.39 Myr for artiodactyls, 3.14-3.31 Myr for perissodactyls and 2.63-2.95 Myr for carnivorous mammals (carnivorans plus creodonts). These averages are based on a much larger, more robust dataset than most previous estimates, so they should be more reliable for any studies that need species longevity to be accurately estimated. © 2013 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

Eye size and visual acuity influence vestibular anatomy in mammals.

PubMed

Kemp, Addison D; Christopher Kirk, E

2014-04-01

The semicircular canals of the inner ear detect head rotations and trigger compensatory movements that stabilize gaze and help maintain visual fixation. Mammals with large eyes and high visual acuity require precise gaze stabilization mechanisms because they experience diminished visual functionality at low thresholds of uncompensated motion. Because semicircular canal radius of curvature is a primary determinant of canal sensitivity, species with large canal radii are expected to be capable of more precise gaze stabilization than species with small canal radii. Here, we examine the relationship between mean semicircular canal radius of curvature, eye size, and visual acuity in a large sample of mammals. Our results demonstrate that eye size and visual acuity both explain a significant proportion of the variance in mean canal radius of curvature after statistically controlling for the effects of body mass and phylogeny. These findings suggest that variation in mean semicircular canal radius of curvature among mammals is partly the result of selection for improved gaze stabilization in species with large eyes and acute vision. Our results also provide a possible functional explanation for the small semicircular canal radii of fossorial mammals and plesiadapiforms. Copyright © 2014 Wiley Periodicals, Inc.

Ontogenetic niche shifts in dinosaurs influenced size, diversity and extinction in terrestrial vertebrates

PubMed Central

Codron, Daryl; Carbone, Chris; Müller, Dennis W. H.; Clauss, Marcus

2012-01-01

Given the physiological limits to egg size, large-bodied non-avian dinosaurs experienced some of the most extreme shifts in size during postnatal ontogeny found in terrestrial vertebrate systems. In contrast, mammals—the other dominant vertebrate group since the Mesozoic—have less complex ontogenies. Here, we develop a model that quantifies the impact of size-specific interspecies competition on abundances of differently sized dinosaurs and mammals, taking into account the extended niche breadth realized during ontogeny among large oviparous species. Our model predicts low diversity at intermediate size classes (between approx. 1 and 1000 kg), consistent with observed diversity distributions of dinosaurs, and of Mesozoic land vertebrates in general. It also provides a mechanism—based on an understanding of different ecological and evolutionary constraints across vertebrate groups—that explains how mammals and birds, but not dinosaurs, were able to persist beyond the Cretaceous–Tertiary (K–T) boundary, and how post-K–T mammals were able to diversify into larger size categories. PMID:22513279

Differentiation of flea communities infesting small mammals across selected habitats of the Baltic coast, central lowlands, and southern mountains of Poland.

PubMed

Kowalski, Krzysztof; Eichert, Urszula; Bogdziewicz, Michał; Rychlik, Leszek

2014-05-01

Only a few studies comparing flea composition on the coast and in the mountains have been conducted. We investigated differences in flea communities infesting small mammals in selected habitats in northern, central, and southern Poland. We predicted (1) a greater number of flea species in the southeastern Poland and a lower number in the north, (2) a greater number of flea species in fertile and wet habitats than in poor and arid habitats, and (3) a low similarity of flea species between flea communities in western and eastern Poland. We found a negative effect of increasing latitude on flea species richness. We suppose that the mountains providing a variety of environments and the limits of the geographic ranges of several flea subspecies in southeastern Poland result in a higher number of flea species. There was a positive effect of increasing wetness of habitat on flea species richness. We found a high diversity in flea species composition between western and eastern Poland (beta diversity = 11) and between central and eastern Poland (beta diversity = 12). Re-colonization of Poland by small mammals and their ectoparasites from different (western and eastern) refugees can affect on this high diversity of flea species.

Sound localization in common vampire bats: Acuity and use of the binaural time cue by a small mammal

PubMed Central

Heffner, Rickye S.; Koay, Gimseong; Heffner, Henry E.

2015-01-01

Passive sound-localization acuity and the ability to use binaural time and intensity cues were determined for the common vampire bat (Desmodus rotundus). The bats were tested using a conditioned suppression/avoidance procedure in which they drank defibrinated blood from a spout in the presence of sounds from their right, but stopped drinking (i.e., broke contact with the spout) whenever a sound came from their left, thereby avoiding a mild shock. The mean minimum audible angle for three bats for a 100-ms noise burst was 13.1°—within the range of thresholds for other bats and near the mean for mammals. Common vampire bats readily localized pure tones of 20 kHz and higher, indicating they could use interaural intensity-differences. They could also localize pure tones of 5 kHz and lower, thereby demonstrating the use of interaural time-differences, despite their very small maximum interaural distance of 60 μs. A comparison of the use of locus cues among mammals suggests several implications for the evolution of sound localization and its underlying anatomical and physiological mechanisms. PMID:25618037

75 FR 18160 - Small Takes of Marine Mammals Incidental to Specified Activities; Antioch Bridge Seismic Retrofit...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-09

... of Marine Mammals Incidental to Specified Activities; Antioch Bridge Seismic Retrofit Project... pile driving associated with the Antioch Bridge Seismic Retrofit Project. DATES: Effective August 15... request from Caltrans to harass marine mammals incidental to the Antioch Bridge Seismic Retrofit Project...

Manipulation complexity in primates coevolved with brain size and terrestriality

PubMed Central

Heldstab, Sandra A.; Kosonen, Zaida K.; Koski, Sonja E.; Burkart, Judith M.; van Schaik, Carel P.; Isler, Karin

2016-01-01

Humans occupy by far the most complex foraging niche of all mammals, built around sophisticated technology, and at the same time exhibit unusually large brains. To examine the evolutionary processes underlying these features, we investigated how manipulation complexity is related to brain size, cognitive test performance, terrestriality, and diet quality in a sample of 36 non-human primate species. We categorized manipulation bouts in food-related contexts into unimanual and bimanual actions, and asynchronous or synchronous hand and finger use, and established levels of manipulative complexity using Guttman scaling. Manipulation categories followed a cumulative ranking. They were particularly high in species that use cognitively challenging food acquisition techniques, such as extractive foraging and tool use. Manipulation complexity was also consistently positively correlated with brain size and cognitive test performance. Terrestriality had a positive effect on this relationship, but diet quality did not affect it. Unlike a previous study on carnivores, we found that, among primates, brain size and complex manipulations to acquire food underwent correlated evolution, which may have been influenced by terrestriality. Accordingly, our results support the idea of an evolutionary feedback loop between manipulation complexity and cognition in the human lineage, which may have been enhanced by increasingly terrestrial habits. PMID:27075921

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.

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.

CERRADO SMALL MAMMALS: a dataset of abundance and distribution of marsupials, lagomorphs, and rodents in a neotropical savanna.

PubMed

Mendonça, André F; Percequillo, Alexandre R; de Camargo, Nicholas F; Ribeiro, Juliana F; Palma, Alexandre R T; Oliveira, Leonardo C; Câmara, Edeltrudes M V C; Vieira, Emerson M

2018-04-27

Patterns in distribution and local abundance of species within a biome are central concerns in ecology and allow the understanding of the effects of habitat loss on rates of species extinction; provide support for the creation and management of reserves; and contribute to the identification and quantification of the processes that allow niche partitioning by species. However, despite the importance in the conservation and management of the ecosystems, most systematized information on the abundance and distribution of small mammals is restricted to the northern hemisphere or forest ecosystems. For tropical biomes, an important part of this information remains dispersed and difficult to access in the form of theses, technical reports or unpublished datasets. Here we present a comprehensive dataset of abundance and richness of small mammals in the Cerrado, the largest Neotropical savanna. This dataset includes 2,599 records of 446 sites from 96 studies. Despite of more than 50% of references in this dataset are peer-reviewed journal articles, 45.78% of communities were compiled from theses. The dataset comprises 24,283 individuals of 55 genera and at least 118 species of small mammals including 29 marsupials, two lagomorphs (one exotic) and 87 rodents (three exotic). Local species richness ranged from one to 26 species (5.82 ±3.55, average species richness ±SD). We observed hyper-dominance of a few species; the 10 most abundant species in this dataset represented 60.19% of all recorded individuals. The hairy-tailed bolo mouse (Necromys lasiurus) represented over than 20% of all individuals and occurred at more than 50% of sites. Furthermore, we identified 18 environments, 16 native vegetation types, and two anthropic environments. Typical savanna and gallery forest were the most frequently sampled vegetation types (comprising 46.94% of all sampled sites) and the most speciose ones (57 species for typical savanna and 53 species for gallery forest). The information

The origin and early evolution of metatherian mammals: the Cretaceous record.

PubMed

Williamson, Thomas E; Brusatte, Stephen L; Wilson, Gregory P

2014-01-01

Metatherians, which comprise marsupials and their closest fossil relatives, were one of the most dominant clades of mammals during the Cretaceous and are the most diverse clade of living mammals after Placentalia. Our understanding of this group has increased greatly over the past 20 years, with the discovery of new specimens and the application of new analytical tools. Here we provide a review of the phylogenetic relationships of metatherians with respect to other mammals, discuss the taxonomic definition and diagnosis of Metatheria, outline the Cretaceous history of major metatherian clades, describe the paleobiology, biogeography, and macroevolution of Cretaceous metatherians, and provide a physical and climatic background of Cretaceous metatherian faunas. Metatherians are a clade of boreosphendian mammals that must have originated by the Late Jurassic, but the first unequivocal metatherian fossil is from the Early Cretaceous of Asia. Metatherians have the distinctive tightly interlocking occlusal molar pattern of tribosphenic mammals, but differ from Eutheria in their dental formula and tooth replacement pattern, which may be related to the metatherian reproductive process which includes an extended period of lactation followed by birth of extremely altricial young. Metatherians were widespread over Laurasia during the Cretaceous, with members present in Asia, Europe, and North America by the early Late Cretaceous. In particular, they were taxonomically and morphologically diverse and relatively abundant in the Late Cretaceous of western North America, where they have been used to examine patterns of biogeography, macroevolution, diversification, and extinction through the Late Cretaceous and across the Cretaceous-Paleogene (K-Pg) boundary. Metatherian diversification patterns suggest that they were not strongly affected by a Cretaceous Terrestrial Revolution, but they clearly underwent a severe extinction across the K-Pg boundary.

Introduced species: domestic mammals are more significant transmitters of parasites to native mammals than are feral mammals.

PubMed

Landaeta-Aqueveque, Carlos; Henríquez, Analía; Cattan, Pedro E

2014-03-01

The study of parasitism related to biological invasion has focused on attributes and impacts of parasites as invaders and the impact of introduced hosts on endemic parasitism. Thus, there is currently no study of the attributes of hosts which influence the invasiveness of parasites. We aimed to determine whether the degree of domestication of introduced mammalian species - feral introduced mammals, livestock or pets, hereafter 'D' - is important in the spillover of introduced parasites. The literature on introduced parasites of mammals in Chile was reviewed. We designed an index for estimating the relevance of the introduced host species to parasite spillover and determined whether the D of introduced mammals predicted this index. A total of 223 introduced parasite species were found. Our results indicate that domestic mammals have a higher number of introduced parasites and spillover parasites, and the index indicates that these mammals, particularly pets, are more relevant introducers than introduced feral mammals. Further analyses indicated that the higher impact is due to higher parasite richness, a longer time since introduction and wider dispersal, as well as how these mammals are maintained. The greater relevance of domestic mammals is important given that they are basically the same species distributed worldwide and can become the main transmitters of parasites to native mammals elsewhere. This finding also underlines the feasibility of management in order to reduce the transmission of parasites to native fauna through anti-parasitic treatment of domestic mammals, animal-ownership education and the prevention of importing new parasite species. Copyright © 2014 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

The influence of foraging mode and arid adaptation on the basal metabolic rates of burrowing mammals.

PubMed

White, Craig R

2003-01-01

Two competing but nonexclusive hypotheses to explain the reduced basal metabolic rate (BMR) of mammals that live and forage underground (fossorial species) are examined by comparing this group with burrowing mammals that forage on the surface (semifossorial species). These hypotheses suggest that the low BMR of fossorial species either compensates for the enormous energetic demands of subterranean foraging (the cost-of-burrowing hypothesis) or prevents overheating in closed burrow systems (the thermal-stress hypothesis). Because phylogentically informed allometric analysis showed that arid burrowing mammals have a significantly lower BMR than mesic ones, fossorial and semifossorial species were compared within these groups. The BMRs of mesic fossorial and semifossorial mammals could not be reliably distinguished, nor could the BMRs of large (>77 g) arid fossorial and semifossorial mammals. This finding favours the thermal-stress hypothesis, because the groups appear to have similar BMRs despite differences in foraging costs. However, in support of the cost-of-burrowing hypothesis, small (<77 g) arid fossorial mammals were found to have a significantly lower BMR than semifossorial mammals of the similar size. Given the high mass-specific metabolic rates of small animals, they are expected to be under severe energy and water stress in arid environments. Under such conditions, the greatly reduced BMR of small fossorial species may compensate for the enormous energetic demands of subterranean foraging.

Comparative study of the innervation of the facila disc of selected mammals.

PubMed

Montagna, W; Roman, N A; Macpherson, E

1975-11-01

The greatest concentration of sensory nerves in the muzzle and facial disc of mammals is in the nose. In most nocturnal mammals, these nerves penetrate the epidermis of the naked nose either or in bundles which resemble the corpuscles of Eimer. The hair follicles around the nose, lips, and eyes, as well as the heaviply innervated vibrissae follicles found in all hairy mammals except man, are well innervated; those elsewhaere are not. Everywhere on the human body both large and small follicles abound in sensory nerves. These morphologic observations suggest that in most mammals the most sensitivie areas of the skin are at the anterior and posterior ends (not reported here), and that human skin is better equipped for cutaneous sensibility than that of any other mammal.

Audubon Mammal Study Program.

ERIC Educational Resources Information Center

National Audubon Society, New York, NY.

Included are an illustrated student reader, "The Story of Mammals," a leaders' guide, a large wall chart picturing 39 North American mammals, and a separate booklet describing the mammals on the wall chart. The student reader presents these main topics: What Is a Mammal?; How Mammals Differ From Each Other; Where, When, and How To Find Mammals;…

Cool running: locomotor performance at low body temperature in mammals.

PubMed

Rojas, A Daniella; Körtner, Gerhard; Geiser, Fritz

2012-10-23

Mammalian torpor saves enormous amounts of energy, but a widely assumed cost of torpor is immobility and therefore vulnerability to predators. Contrary to this assumption, some small marsupial mammals in the wild move while torpid at low body temperatures to basking sites, thereby minimizing energy expenditure during arousal. Hence, we quantified how mammalian locomotor performance is affected by body temperature. The three small marsupial species tested, known to use torpor and basking in the wild, could move while torpid at body temperatures as low as 14.8-17.9°C. Speed was a sigmoid function of body temperature, but body temperature effects on running speed were greater than those in an ectothermic lizard used for comparison. We provide the first quantitative data of movement at low body temperature in mammals, which have survival implications for wild heterothermic mammals, as directional movement at low body temperature permits both basking and predator avoidance.

High-impact conservation: invasive mammal eradications from the islands of western México.

PubMed

Aguirre-Muñoz, Alfonso; Croll, Donald A; Donlan, C Josh; Henry, R William; Hermosillo, Miguel Angel; Howald, Gregg R; Keitt, Bradford S; Luna-Mendoza, Luciana; Rodríguez-Malagón, Marlenne; Salas-Flores, Luz María; Samaniego-Herrera, Araceli; Sanchez-Pacheco, Jose Angel; Sheppard, Jacob; Tershy, Bernie R; Toro-Benito, Jorge; Wolf, Shaye; Wood, Bill

2008-03-01

Islands harbor a disproportionate amount of the earth's biodiversity, but a significant portion has been lost due in large part to the impacts of invasive mammals. Fortunately, invasive mammals can be routinely removed from islands, providing a powerful tool to prevent extinctions and restore ecosystems. Given that invasive mammals are still present on more than 80% of the world's major islands groups and remain a premier threat to the earth's biodiversity, it is important to disseminate replicable, scaleable models to eradicate invasive mammals from islands. We report on a successful model from western México during the past decade. A collaborative effort between nongovernmental organizations, academic biologists, Mexican government agencies, and local individuals has resulted in major restoration efforts in three island archipelagos. Forty-two populations of invasive mammals have been eradicated from 26 islands. For a cost of USD 21,615 per colony and USD 49,370 per taxon, 201 seabird colonies and 88 endemic terrestrial taxa have been protected, respectively. These conservation successes are a result of an operational model with three main components: i) a tri-national collaboration that integrates research, prioritization, financing, public education, policy work, capacity building, conservation action, monitoring, and evaluation; ii) proactive and dedicated natural resource management agencies; and iii) effective partnerships with academic researchers in Mexico and the United States. What is now needed is a detailed plan to eradicate invasive mammals from the remaining islands in the region that integrates the needed additional financing, capacity, technical advances, and policy issues. Island conservation in western Mexico provides an effective approach that can be readily applied to other archipelagos where conservation efforts have been limited.

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