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Noninvasive genetic surveys, often conducted by collecting fecal samples, have become a popular tool for surveying wildlife, but have primarily been applied to species with large and conspicuous scat. Although many small mammals are threatened, endangered, or data deficient, noninvasive genetic surveys have rarely been applied due to the challenges of detecting their inconspicuous fecal pellets. As part of a broader study of the endangered salt marsh harvest mouse (Reithrodontomys raviventris), we developed a noninvasive genetic survey technique for the community of small mammals in their putative range. We designed bait stations to passively collect fecal samples from rodents, and developed a multiplex primer set that amplified unique fragment sizes for salt marsh harvest mice and four other sympatric species. We tested the primer set on positive controls and on fecal pellets collected from bait stations at two regularly monitored field sites known to have very different densities of salt marsh harvest mice. The multiplex amplified DNA from all five species, even when all five species were present in a single sample. A positive species identification was made for all field-collected samples, and 43% of these field-collected samples had multispecies detections. The combination of bait stations and genetic species identification proved to be an effective means of noninvasively surveying small mammals in potential salt marsh harvest mouse habitat. The sampling technique should be applicable to a wide variety of small mammals in other systems.

Closely related species are predicted to have similar fundamental niches, and therefore to compete locally and possibly be constrained to occur allopatrically. Over time, niche differentiation should lead to divergent use of niche axes, such as food or habitat. Most studies of niche divergence or of niche conservatism have focused on multiple species at large spatial scales. We studied two species of closely related chipmunks at two spatial scales in the northern Sierra Nevada. The Long-eared Chipmunk (Tamias quadrimaculatus) and the Shadow Chipmunk (T. senex) are subcryptic species that exhibit extensive geographic overlap in the northern and central Sierra Nevada. Habitat use at the macrohabitat scale was similar, with both species reaching their highest mean abundance in Red Fir (Abies magnifica) forests, but exhibiting divergent secondary affinities. Additionally, macrohabitat associations of T. senex appear to differ from those reported 50 years ago within the same forest, suggesting flexibility in the face of structural habitat changes resulting from forest management actions, climate change, or other factors. At a finer spatial scale, habitat affinities of these chipmunks differed modestly, suggesting that local distribution emphasizes slightly different microhabitat characteristics. We conclude that these species exhibit niche conservatism overall, but whether microhabitat differences reflect competition or niche divergence requires further study. Because T. quadrimaculatus has the smallest geographic range of any Sierra Nevada sciurid, it may be at risk of local extirpation or substantial range restriction in the face of climate change, large-scale high-severity wildfires, and other stochastic threats; the present research sheds light on the ecology of these species, but has important relevance for regional resource managers as well.

Despite increasing awareness of the ecological roles and ecosystem services that bats provide, spatiotemporal patterns in bat abundance and community assembly remain poorly understood outside of select sites in the tropics. We conducted systematic full-spectrum acoustic surveys of bats over the course of a year at eight permanent sites spanning nearly 50 km along Putah Creek, a stream in California’s Central Valley that has been subject to restoration efforts and changes to its in-stream flow regime over the past two decades. We surveyed all sites for 1 week each month. In 158 sampling nights over 11 months, we recorded 157,762 identifiable calls, thereby documenting a rich bat assemblage comprising 15 species from eight genera and two families. Seven species appeared to occur here year-round, whereas six others evidently migrated seasonally, and two were incidental visitors. Species richness and activity diversity were effectively invariant across this 50-km gradient, but assemblage composition varied both spatially and temporally. Spatial patterns suggest species-specific distributions that presumably reflect individualistic habitat preferences and responses to extrinsic factors. Species also varied temporally, with bat activity generally declining in winter, with an unexpected dip in richness and activity in late spring. For the three most commonly detected species, generalized linear models further highlighted the species-specific and individualistic nature of spatiotemporal activity patterns. When integrated with available data from other temperate sites, our results suggest that local species richness is high in temperate riparian systems. Additionally, our observations suggest that species responses to environmental variation are individualistic (e.g., “Gleasonian”) in nature and that local composition varies greatly over spatiotemporal gradients, but that emergent assemblage characteristics do not. The generality of these observations, and the underlying mechanism(s) leading to invariance in emergent characters, warrant further investigation. Similarly, the extent to which greater bat species richness provides complementary ecosystem services (hence, ecological insurance) is of both ecological and economic interest.

Elevational gradients coincide with expansive climatic gradients and diverse plant and animal communities. We evaluated the small mammal assemblages in eight distinct vegetation types across an elevational gradient in southern California, the Deep Canyon Transect, to determine how assemblage composition changes across the gradient and to identify species with similar habitat associations. Livetrapping efforts (4,800 trap-nights) yielded 1,097 captures of 713 individuals, representing 14 heteromyid and cricetid species. Heteromyids dominated the six lower-elevation vegetation types (< 1,300 m a.s.l.), whereas cricetids dominated the upper end of the gradient. Richness and diversity exhibited bimodal responses to elevation, which do not conform to mid-domain effect null predictions. Canonical correspondence analysis revealed that 75% of the variation in small mammal abundances was explainable by habitat characteristics, and cluster analysis grouped small mammals into three ecologically distinct groups based on their habitat associations. One contained only Chaetodipus penicillatus, while the others were comprised of low- and high-elevation species, respectively. The low-elevation species exhibit unusual levels of sympatry (and syntopy) among closely related species of pocket mice (Chaetodipus). Further efforts should investigate the mechanisms of coexistence for Chaetodipus species with nearly identical associations and seasonal effects on richness and diversity. Repeated surveys of entire gradients such as the Deep Canyon Transect will help refine our understanding of temporal dynamics of community assemblage and diversity.

The study of mammals has promoted the development and testing of many ideas in contemporary ecology. Here we address recent developments in foraging and habitat selection, source–sink dynamics, competition (both within and between species), population cycles, predation (including apparent competition), mutualism, and biological invasions. Because mammals are appealing to the public, ecological insight gleaned from the study of mammals has disproportionate potential in educating the public about ecological principles and their application to wise management. Mammals have been central to many computational and statistical developments in recent years, including refinements to traditional approaches and metrics (e.g., capture-recapture) as well as advancements of novel and developing fields (e.g., spatial capture-recapture, occupancy modeling, integrated population models). The study of mammals also poses challenges in terms of fully characterizing dynamics in natural conditions. Ongoing climate change threatens to affect global ecosystems, and mammals provide visible and charismatic subjects for research on local and regional effects of such change as well as predictive modeling of the long-term effects on ecosystem function and stability. Although much remains to be done, the population ecology of mammals continues to be a vibrant and rapidly developing field. We anticipate that the next quarter century will prove as exciting and productive for the study of mammals as has the recent one.

© Published by Oxford University Press on behalf of American Society of Mammalogists 2018. Quantifying reproductive parameters is essential for developing effective conservation plans for species of concern; however, studying reproduction in wild settings can be challenging and local data are frequently unavailable. The fisher (Pekania pennanti) is an elusive forest-dwelling carnivore of conservation concern that occurs across much of boreal North America and reaches the southernmost limit of its distribution in the southern Sierra Nevada (SSN) in California. Data on fisher reproduction in this region are limited and applicability of parameters from other areas is uncertain. To clarify how fisher populations in the SSN compare with those elsewhere in North America, we conducted a comprehensive review of available literature on reproduction throughout the species' range in North America. We then compared findings from the review with data we collected during 7 years in the SSN, focusing on the proportion of females reproducing, litter size, and the parturition date. On average across the fisher's range, the proportion of adult females that reproduced was 0.71 (range: 0.40-1.00; n = 16 studies), litter size was 2.5 (range: 1-4; n = 16 studies), and parturition occurred on 25 March (range: 3 March-17 April; n = 16 studies). In our study area, we tracked 42 adult female fishers, 35 of which reproduced and used 257 reproductive dens (74 natal, 175 maternal, 8 early failures); 0.86 of our females attempted denning (range: 0.79-1.0; n = 93 opportunities) and 0.75 were successful (range: 0.64-1.0; n = 91 opportunities monitored through the den season). Mean litter size was 1.57 (range: 1-3; n = 75 litters) and mean parturition date was 30 March (range: 17 March-12 April; n = 69 natal dens initiated). Female fishers at the southern limit of their distribution in the SSN reproduced at a rate comparable to or higher than elsewhere in North America, but average litter size was the lowest reported for the species. Female fishers in the SSN gave birth at similar or later dates than elsewhere in their range. We explore factors that might explain patterns of variation in fisher reproductive parameters and discuss conservation implications of our findings.

International audience; Long-term studies on rodents have been conducted for longer periods (up to 70 years) and more generations (upto 88 generations) than for most other mammalian taxa. These studies have been instrumental in furthering ourunderstanding of ecophysiology, social systems, and population and community processes. Studies on Africanstriped mice (Rhabdomys pumilio) revealed that basal blood glucose levels span a far greater homeostatic rangethan previously thought. Studies on American red squirrels (Tamiasciurus hudsonicus) demonstrated howendocrine pathways underlying phenotypic plasticity allow individuals to respond to different environments.Long-term studies on African striped mice, marmots (Marmota), tuco-tucos (Ctenomys sociabilis), and degus(Octodon degus) revealed that ecological constraints on dispersal are drivers of group formation in some speciesbut not others. Social flexibility, when the social system of an entire population can change due to individualschanging their social tactics, has been demonstrated in striped mice. Long-term studies on prairie voles (Microtusochrogaster) found that males and females often live in pairs, leading to subsequent studies of the neuralmechanisms underlying social monogamy. Long-term studies on other arvicoline rodents contributed more toour understanding of the factors influencing population dynamics than studies on any other mammalian order.While food availability and predation have been identified as factors influencing population dynamics, no singlefactor alone drives population dynamics in any species. We encourage researchers to incorporate manipulativeexperiments into long-term studies and to take integrative approaches to inform cross-disciplinary theory.

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 standreplacing 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.

Effective restoration of threatened or endangered species requires understanding of basic ecological requirements such as habitat selection and home range needs. The endangered riparian brush rabbit (Sylvilagus bachmani riparius) occupies areas of dense, brushy cover along streamside communities in the San Joaquin Valley of California, but over 93% of this habitat has been lost to urban and agricultural development. We released over 325 captive-born rabbits at the San Joaquin River National Wildlife Refuge (Refuge) between July 2002 and July 2005, and we monitored 312 of these rabbits via radiotelemetry to assess spatial and habitat selection. Home ranges and core areas were similar among males and females, and were larger in the breeding season than during the nonbreeding season. Perhaps reflecting a growing population, home range estimates decreased in size over the duration of the study. Animals moved in response to a wildfire in July 2004, but home range area was similar in 90-day pre- and po...

Patton, J. L., U. F. J. Pardinas, and G. D’Elia (eds.). 2015. Mammals of South America, Vol. 2. Rodents. University of Chicago Press, Chicago, Illinois, xxvi + 1336 pp. ISBN 978-0-226-16957-6, price (hard cover), $95. The second volume of Mammals of South America (MSA2) lives up to the hopes built up over 3 decades of anticipation. The 1st volume (MSA1—Gardner 2007) established a high bar for excellence (Kelt 2009; Voss 2009); Patton et al. and their able army of authors have met that with a groundbreaking synthesis of all things Rodentia on the Green Continent. This book is comprehensive, sweeping in scope and depth, and eminently readable. It provides the first such treatise on rodents of any such area with such detail. Whatever facet of mammal biology you study, if it involves South American rodents this book has information of relevance to your research. When I reviewed MSA1 (Kelt 2009) I noted that “If [this] is any indication of what’s coming, then . . . South American mammals are finally getting the synthesis they deserve.” MSA2 makes it clear that all hopes are more than met! I cannot wait for MSA3. MSA2 is structurally similar to MSA1. Following 26 pages of introductory materials, the taxonomic accounts comprise 1,048 pages with impressively few typographic errors. This is followed by 159 pages of Literature Cited, a 67-page Gazetteer, a 9-page list of taxa (627 species in 143 genera), 4 pages to list the 56 contributors (from 11 countries), and a 46-page Index. Reflecting the remarkable growth in Latin American mammalogy in recent years, 41 authors hail from either Mexico ( n = 2) or from 8 South American countries. Keys (mostly dichotomous) are provided for all genera and most species. For all genera, the authors provide General Comments (often including highly readable distillations of otherwise complex taxonomic histories), a Synonymy, Remarks, and a Key to Species, followed by presentation of all species in alphabetical order (in some cases, such as Proechimys , where species groups are … Department of Department of Wildlife, Fish, & Conservation Biology, University of California, Davis, CA 95616, USA; e-mail: dakelt{at}ucdavis.edu.

Forests in the Sierra Nevada, similar to those across the continent, have been substantially altered by logging, fire exclusion, and other human activities. Current forest management emphasizes maintenance or restoration of resiliency in the face of contemporary disturbance factors that include wildfire, climate change, continued urbanization, and invasive species. We evaluated responses of small mammals to forest management by monitoring a series of 12 replicate trapping grids in compositionally homogeneous forest over 8 years, and implemented 2 levels of canopy thinning. Livetrapping efforts (119,712 trap-nights) yielded 15,613 captures of 2,305 individuals of 13 species, and although forest structure was significantly influenced by canopy treatments, small mammal numbers and assemblage composition were not. To better understand this we assessed habitat associations of small mammals at 599 census points on 75 transects established in a stratified random manner throughout Plumas National Forest....

We studied the association between space sharing and kinship in a solitary rodent, the dusky-footed woodrat (Neotoma fuscipes). Genetic relatedness was inversely correlated with geographic distance for female woodrats but not for males, a pattern consistent with female philopatry and male dispersal. However, some female neighbors were unrelated, suggesting the possibility of female dispersal. Relatedness of female dyads was positively correlated with overlap of their home ranges and core areas, indicating that females were more likely to share space with relatives, whereas males showed no correlation between relatedness and the sharing of either home ranges or core areas. However, some females that shared space were not close relatives, and some closely related males shared space. House sharing was exhibited both by close relatives and by distantly related or unrelated woodrats, and was not correlated with relatedness. The kin structuring we describe likely resulted from a pattern of female philopatry and male dispersal, but also may have resulted from kin-directed behaviors by females.

Rooted in the conceptual revolutions of the 1960s and 1970s, contemporary research on the ecology of desert small mammals has progressed markedly in recent decades. Areas of particular emphasis include the role of extrinsic (e.g., climate) compared with intrinsic (e.g., density-dependence) factors on population growth and associated metrics, the role of competition compared with predation in influencing foraging decisions and habitat selection, the influence of small mammals on community structure and composition via consumption and redistribution of plant materials, and as ecological engineers and keystone species (or guilds). Recent emphasis on the energetic basis of assemblage composition is intriguing and warrants further work, and the generality of zero-sum dynamics requires further assessment. Desert systems continue to be the focus of much ecological research, and small mammals remain central figures in understanding the interplay between biotic and abiotic factors and between intrinsic and extrinsic drivers. Small mammals in deserts worldwide exemplify the importance of diverse approaches to ecological research, including local manipulative field experiments, long-term demographic monitoring, and both laboratory and field-based studies on behavioral and foraging ecology.

The American Society of Mammalogists herein provides revised guidelines for personnel working with rodents potentially infected with viruses that cause hantavirus pulmonary syndrome (HPS) in humans. We also clarify that previously published guidelines, including those of the United States Centers for Disease Control and Prevention (CDC), were not intended to apply to field-workers conducting nonviral-based research on rodents. Unfortunately, institutional animal care and use committees and other safety officers have assumed that current CDC recommendations are requirements for conducting safe field research. They then have misapplied the original CDC recommendations to field researchers conducting behavioral, ecological, taxonomic, and other research, making field research increasingly and unnecessarily difficult. Herein, we provide guidelines that have been modified from those published by the CDC to incorporate new information about HPS risk and to better match the level of personal protection to the level of risk associated with a wider array of field activities.

We studied the spatial organization of dusky-footed woodrats (Neotoma fuscipes) in mixed-conifer forest of the northern Sierra Nevada, California, by radiotracking 63 adult woodrats at 2 study sites during May–October 2004–2006. Estimates of home-range and core-area size differed between study sites, but they were within the range reported elsewhere; variability in home-range size was explained in part by density. Home ranges of woodrats overlapped those of multiple neighboring woodrats, both same sex and opposite sex, suggesting that foraging areas were shared. However, core areas showed little overlap between same-sex neighbors. Woodrats occupied multiple houses and frequently moved among them, and sharing of houses (either simultaneously or nonsimultaneously) with neighboring woodrats was common but occurred mostly between male–female pairs. Females typically shared their core area and houses with 1 male, whereas males shared core areas and houses with multiple females; further, males moved more than females. Our results suggest that dusky-footed woodrats are semiterritorial, maintaining near-exclusive use of their core area and houses against same-sex conspecifics, and that the mating system likely is polygynous.

Lower-elevation habitats of north-central Chile are characterized by semiarid vegetation that is strongly influenced by rainfall related to El Nino Southern Oscillation (ENSO) events. During the ENSO warm phase (i.e., El Nino), heavy rains occur resulting in small mammal irruptions or ratadas. During prevailing drier periods, pronounced droughts result in reductions in small mammal densities and local extinctions of some species. Within the dominant thorn-scrub habitat of a national park, we identified 2 other habitat types, aguadas (riverine shrublands) and fog-forest patches that serve as refuges for small mammals during dry years. We divide small mammal species of the thorn scrub into 2 groups: core species (Octodon degus, Phyllotis darwini, Abrothrix olivaceus, and Thylamys elegans) maintain populations at all times, whereas opportunistic species (Oligoryzomys longicaudatus and A. longipilis) are present only after rains. The latter group appears to maintain refuge populations in aguadas and fog forests and to opportunistically exploit the thorn scrub when conditions are favorable. Aguadas also may play an important role in the persistence of less-common species, such as Octodon lunatus and Abrocoma bennetti. Despite being small and patchily distributed, aguadas are important for the maintenance of regional biodiversity.

We augmented food resources to a heteromyid rodent community in the Sonoran Desert of southern California to experimentally ascertain the effect of a resource pulse on rodent abundance, diversity, and home-range dynamics. The same community displayed increased rodent abundance and species diversity in response to the productivity pulse that resulted from the 1997–1998 El Nino Southern Oscillation (ENSO). In marked contrast to the response to the ENSO, our experiment resulted in a decline in rodent diversity because the largest pocket mouse present (Chaetodipus formosus) monopolized the added resources and increased its proportional abundance. In addition, the abundance of adult rodents did not change in response to supplemental resources, even though reproduction, and consequently juvenile abundance, increased greatly. This implies that home-range size and overlap by adult animals remained unchanged despite the greater abundance of food. Among caching species such as pocket mice, this may be an a...

Effective management strategies require an understanding of the spatial scale at which fauna use their habitat. Toward this end, we sampled small mammals in the northern Sierra Nevada, California, over 2 years at 18 livetrapping grids among 5 forest types. Forest types were defined by overstory tree composition, and 19 microhabitat variables were measured at all trap stations. Forest type and year explained 93% of variation in abundance of North American deermice (Peromyscus maniculatus), whereas only 40% was explained by microhabitat and year. Similarly, variation in abundance of long-eared and shadow chipmunks (Neotamias quadrimaculatus and N. senex) was better explained by forest type and year (67%) than by microhabitat and year (30%). Red fir (Abies magnifica) forests supported more P. maniculatus and Neotamias species than mixedconifer and pine‐cedar forests, and more Neotamias species than mixed-fir forests. Five of 6 uncommon species were significantly associated with forest type; golden-mantled ground squirrels (Spermophilus lateralis), northern flying squirrels (Glaucomys sabrinus), and long-tailed and montane voles (Microtus longicaudus and M. montanus) were captured almost exclusively in red fir forests, whereas dusky-footed woodrats (Neotoma fuscipes) and California ground squirrels (Spermophilus beecheyi) were found in pine‐cedar, mixed-fir, and mixed-conifer forests. The first 2 axes of a canonical correspondence analysis on microhabitat variables explained 71% of variation in combined small mammal abundance. Microhabitat associations varied among species but were driven primarily by canopy openness, shrub cover, and shrub richness. Although much of the small mammal fauna appeared to select habitat at both spatial scales studied, canonical correspondence analysis using forest type as a covariate revealed that microhabitat explained much less variation in small mammal abundance than did forest type.

In southern California the Dulzura kangaroo rat (Dipodomys simulans) occurs in shrub-dominated habitats adjacent to forb- or grass-dominated habitats, which support the endangered Stephens's kangaroo rat (D. stephensi). We monitored a number of populations of both species from 1996 through 2000, spanning the 1997- 1998 El Nino Southern Oscillation (ENSO) event. Although populations of D. stephensi were not significantly impacted by this climatic event, D. simulans declined from 10-24 individuals/ha to about 7-12 individuals/ha over a 6- to 8-month period; numbers subsequently continued to decline to 1-2 individuals/ha and failed to recover in the approximately 2.5 years of post-ENSO monitoring. We noticed no signs of sickness or illness among these animals, although adult body masses of D. simulans (but not D. stephensi) declined through the ENSO event, suggesting that food resources for the former species may have been compromised. Alternatively, populations of D. simulans may have been unusually high before the ENSO event, such that the onset of rains merely hastened a predictable winter die-off. Finally, other rodents could have robbed seeds from the food caches of Dulzura kangaroo rats, influencing the ability of the latter to survive the ENSO event. Although this explanation remains speculative, cache pilferage has been demonstrated among other heteromyids, and a recent theoretical study suggests this may be an important mechanism of species coexistence. Further investigations of cache pilferage could enhance our understanding of the ecology and evolution of these diverse small mammal assemblages.

We examined the nest-tree preferences of northern flying squirrels (Glaucomys sabrinus) in an old-growth, mixed-conifer and red fir (Abies magnifica) forest of the southern Sierra Nevada of California. We tracked 27 individuals to 122 nest trees during 3 summers. Flying squirrels selected nest trees that were larger in diameter and taller than either random trees or large (.50-cm diameter at breast height) nearest-neighbor trees. Snags were used more often than live trees relative to their availability. Nest trees were usually close to riparian habitat; 86% of nest trees were ,150 m from a perennial creek. Flying squirrels selected red fir and avoided incense cedar (Calocedrus decurrens). Mean distances between nest trees and size of core-nest areas were greater for males than for females. No detectable relationship was found between size of core-nest area and distance to a perennial creek. These results suggest that flying squirrels of the Sierra Nevada may require large trees and snags within 150 m of perennial creeks for their critical habitat needs.

Understanding patterns of burrow-use behavior can provide insights into social structure and may have important implications for management of threatened or endangered species. Most kangaroo rat species are assumed to be solitary, but some populations of the endangered Stephens’ kangaroo rat (Dipodomys stephensi) exhibit aggregated burrow associations. Observation of burrow-use patterns over a period of 2 years allowed us to assess the extent of burrow sharing, providing insights into the degree of sociality in this species. Understanding burrow-use patterns also is critical for conservation because the most widely used technique for population estimation for this species relies on a linear relation between burrow density and population size. Although the density of burrow entrances is known to correlate positively with population density, very little is known about how robust this correlation is in the face of changing demographic and environmental variables. Over 14 threenight sessions, burrow entrance sharing occurred between 26% of individuals, with up to 4 individuals sharing a single burrow entrance. The predominant burrow sharing combination (42%) was adult males with adult females. The number of burrow entrances used varied by location and by age of inhabitant. The relationship between density of burrow entrances and that of D. stephensi varied significantly by location but not by date, and individuals in high-density populations used fewer burrow entrances than individuals in low-density populations. Consequently, variation in location, population density, and ratio of juveniles to adults should all be considered when using the method of counting burrow entrances to estimate population size. When these factors vary, the relationship of burrow entrance count to D. stephensi density may need to be recalibrated to predict density accurately. We recommend this method be employed cautiously and that results obtained be interpreted as conservative estimates of population size.

Schmidly, D. J., W. E. Tydeman, and A. L. Gardner (eds.). 2016. United States Biological Survey: A Compendium of its History, Personalities, Impacts, and Conflicts. Special Publications, Museum of Texas Tech University, Lubbock, Vol. 64, ix + 124 pp. ISBN 1-929330-28-6, price (hard cover), $24.95. In 2013, David Schmidly gave a talk at the ASM meeting on the life and career of Vernon Bailey, one of the most productive and well-known biologist with the United States Biological Survey (Survey—Schmidly 2013). This was sufficiently well received that Schmidly was invited to organize a symposium the following year that expanded the theme to address the role and influence of the Survey on natural history in North America (Schmidly and Gardner 2014). This also was well received and subsequently prepared as a series of chapters in the volume under review here. I asked to provide this unsolicited review … Department of Wildlife, Fish, and Conservation Biology, University of California, Davis, Davis, CA 95616, USA; e-mail: dakelt{at}ucdavis.edu

Seasonal reliance on plant-based resources is very uncommon in temperate insectivorous bats. The pallid bat (Antrozous pallidus) is an exception and in the Sonoran Desert switches from an arthropod-based diet to one that includes cactus nectar during spring when columnar cacti bloom. Such cactophily is a common strategy among nectar-feeding phyllostomid bats, including migratory Leptonycteris species that consume nectar and fruit from columnar cacti. Spring nectarivory by A. pallidus begs the question of whether they also consume cactus fruit during the summer, despite lacking morphological and physiological adaptations for frugivory. We recorded foraging behavior of bats at 134 fruits of the cardon cactus (Pachycereus pringlei) in Baja California Sur, Mexico, and used stable isotope analysis to quantify incorporation of fruit into the summer diet of A. pallidus. We found that A. pallidus visited cardon fruits just as frequently as the lesser long-nosed bat, Leptonycteris yerbabuenae (51.0% and 49.0% of total observed visits, respectively), and removed the same amount of fruit (t59 = –0.85, P = 0.40). Carbon isotopes in wing tissue (n = 37) and exhaled breath (n = 35) of A. pallidus were consistent with frugivory, although variability in the proportion of cactus-derived δ13C in A. pallidus was higher in summer than in spring. Our results confirm that nectarivory in A. pallidus extends to frugivory, highlighting remarkable dietary plasticity in a temperate bat. Moreover, these data suggest that A. pallidus may be an important mutualist to columnar cacti in parts of the Sonoran Desert.

Reanalysis of a recently published data set on the responses of 2 species of kangaroo rats to the 1997-1998 El Nino Southern Oscillation (ENSO) event revealed an error during data manipulation, and underscored the perils associated with electronic data storage, manipulation, and analyses. Renewed analyses revealed that Dipodomys simulans was not catastrophically impacted by the ENSO event. Both species were negatively impacted by 2 separate rainy periods, and both species appeared to recover rapidly. The rate of demographic recovery may be a function of habitat preferences. Dipodomys stephensi occurs in valley bottoms and recovered numerically only after cessation of rains, whereas D. simulans, which occurs on better-drained habitat in adjacent hill slopes, appeared to initiate demographic recovery half way through the rainy period associated with the 1998 ENSO. In contrast, however, D. simulans was not observed to recover for about 5 months after the rainy period in 2000.

Abundances of species of small mammal in typical southern-Valdivian, temperate rainforest decline and those of more xeric-adapted species of Patagonian steppe increase across a major environmental gradient in southern Chile. Despite heterogeneous and skewed distributions of all individual species across this transition, community characteristics including species richness, community evenness, biomass of trophic groups (animalivores, folivores, fungivores, granivores, omnivores), and total biomass of rodents do not change significantly across this gradient. Across this transition, local (ecological) processes evidently compensate for geographical (historical) constraints, yielding remarkably constant community dynamics. Species richness of small mammals in this region appears limited by availability of resources rather than the pool of species available to colonize a site.

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 historic fire frequencies. We summarize these patterns and proposed mechanisms, and we integrate data from 2 other studies—1 in the Sierra Nevada and 1 from an evolutionarily related mountain range in Baja California—to provisionally conclude that evolutionary adaptation, and possibly climatic warming in the Holocene, likely are the primary drivers of this faunal structure. However, we agree with work elsewhere in North America that recent anthropogenic filtering likely has amplified the effects of adaptation and climatic warming; one result of this is that the Sierra Nevada currently supports very limited areas of older (decadent) forests, and species dependent on these habitats may require special attention by resource managers.

Multivariate analyses of distributions of small mammals identified important habitat associations in a precordilleran temperate rainforest in southern Chile. Significant differences in vegetation were found between summer (January–March) and winter (July–August) periods, indicating that multiple-season studies may be necessary to fully assess habitat preferences of small mammals. Three species of sigmodontines ( Akodon olivaceus, Abrothrix longipilis, Abrothrix sanborni ), and a putative A. longipilis × A. sanborni hybrid, showed moderate habitat preferences with considerable interspecific overlap. Habitat associations of Oligoryzomys longicaudatus , a sporadic resident, were significantly different from those of the akodonts, perhaps reflecting transient status in the community; other species generally had insufficient captures for quantitative comparisons. These patterns of habitat association differ from those of previous studies and suggest the consequences of methodological, spatiotemporal, and demographic factors in the interpretation and detection of multivariate ecological relationships.

S. Chester 2008. A Wildlife Guide to Chile, Continental Chile, Chilean Antarctica, Easter Island, Juan Fernandez Archipelago. Princeton University Press, Princeton, New Jersey, and Oxford, United Kingdom, viii + 392 pp. ISBN 978-0-691-12976-1, price (paper), $19.95. For 13 years, Sharon Chester served as a natural history lecturer on expedition cruise ships to Chile and the Antarctic. These experiences, and the questions posed by cruise passengers, prompted her to develop a “field guide” that would provide the educated layperson (and dare I say many academics as well) with a treatment of the avian and mammal fauna of Chile. This was quickly broadened to include Chilean geography and plants, and subsequently butterflies and herpetiles as well. The result of her efforts is the only volume available that covers such an array of material for this country. Spanning almost 40° latitude plus a wedge of Antarctica, and ranging from sea level to nearly 7,000 m elevation, Chile boasts a diverse array of environments and habitats, with concomitant diversity in its flora and fauna. In spite of a wealth of material to include in a compact and handy field guide, Chester has produced a delightful guide for ecotourists and field biologists alike. This book includes 9 core chapters that address Chile and Her Sovereignties (20 pp.), Marine Resources (11 pp.), Floristic Zones (41 pp.), Botanical Descriptions (17 pp.), Butterflies and Moths (16 pp.), Reptiles and Amphibians (20 pp.), Birds (165 pp.), Mammals (58 pp.), and Where to See Wildlife (26 pp.). These core chapters are followed by a brief glossary, a 1-page Spanish–English dictionary, bibliography, separate indices to scientific and common names, and a “quick index” to color illustrations and maps. The chapter on marine resources will provide the landlubber with perhaps his or her 1st view of typical Chilean seafood, but also a brief guide to denizens of Chile's extensive intertidal regions. Coverage of vegetation and plant species is appropriately superficial but this is neither a detriment nor is it unexpected; this book is intended as a …

In the world of taxonomy and nomenclature, timing can be everything. A new species described yesterday takes precedence over the same entity described today. Consequently, it is essential that the Journal of Mammalogy makes every effort to facilitate the rapid dissemination of new names and nomenclatural acts, according to current nomenclature rules. The International Commission on Zoological Nomenclature (ICZN—iczn.org) oversees the International Code of Zoological Nomenclature (The Code—ICZN 1999) that governs and provides structure to nomenclatural issues. The Code specifies that scientific names are valid and accepted only if they meet specific criteria …

J. L. Long 2003. Introduced Mammals of the World: their History, Distribution and Abundance. CSIRO Publishing, Collingwood, Victoria, Australia, and CABI Publishing, Wallingford, United Kingdom, xxi + 589 pp. ISBN 0-643-06714-0, price (hardbound), $135.00. Humans have been introducing animals to various regions of the world since before recorded history. Although John Long doesn't address prehistoric introductions, this tome constitutes a major undertaking to summarize historic introductions of mammals. We owe a debt of gratitude to Peter Mawson, who took on the job of completing this project when John Long passed away in 2000. After a key to the maps in the book, a short preface, acknowledgments, and a prologue (by Mawson), the book begins with a brief but synoptic introduction. Prepared by Mawson, this outlines in very readable format the reasons mammals have been introduced (esthetics, hunting, commerce, pest control, accidental escape), the principal global regions where mammals have been introduced, both the menace of successful introductions (e.g., competition, disease, hybridization, etc.) and the potential benefits (e.g., recreation, pest control), and some speculation on the future of introductions in the modern jet age. A one-page table summarizes the numbers of …

G. A. Feldhamer, B. C. Thompson, J. A. Chapman (eds.). 2003. Wild Mammals of North America: Biology, Management, and Conservation, 2nd ed. The Johns Hopkins University Press, Baltimore, Maryland, xiii + 1216 pp. ISBN 0-8018-7416-5, price (hardbound), $165.00. The 2nd edition of Wild Mammals of North America (WM IT) is an ambitious volume. Weighing in at 2.67 kg (the 1st edition— WM I —was 1.99 kg), this book is a larger format than the 1st edition (22.4 x 28.2 cm compared with 18.9 x 26.3 cm) and is 69 pages longer; the price has more than tripled (but remains under $0.07/p.). Much has been learned in the intervening 22 years, however, so perhaps these quantitative differences are to be expected. What about the qualitative? The first edition of this book (Chapman and Feldhamer 1982) was met with positive reviews (e.g., Jones 1983; Koplin 1983; Seidensticker 1983) and has been a stalwart in many libraries for a number of years. I beheve the 2nd edition will carry on this tradition. Like its predecessor, this volume focuses on “pertinent life history and management information for mammalian species or species groups of management significance in North America” (p. ix). H^M/presented 57 chapters by 87 authors, whereas WM II presents 55 chapters by 100 authors; only 26 authors from WM I remain in WM II . Two chapters have been added (black-tailed prairie dogs, eastem woodrats), 1 deleted (Norway rat and allies), and 3 pairs of chapters have been combined (2 chapters on foxes, 2 on skunks, and separate chapters on fisher and marten; the latter 2 had identical author lines in WM I) . As with WM I , these chapters are followed by 2 appendices, a brief glossary, and an index. All chapters have been updated with recent literature, albeit to differing extents. Some chapters have similar author lines as in the 1982 edition, but are genuine updates on the earlier edition, with extensive updates and recent citations. Many other chapters have entirely new authors and generally represent …

S. Oldfield 2003. Rainforest. MIT Press, Cambridge, Massachusetts, in association with Fauna and Flora International, 160 pp. ISBN 0-262-15106-5, price (cloth) $29.95. Rainforest is a coffee table book of wonderful production. Following a foreword that outlines rainforest diversity and both present threats and future options for rainforests, 9 chapters address major rainforest regions of the world, including 1 on temperate rainforests. Nearly 200 photographs underscore the diversity and beauty of rainforest biota and biological processes and do service to the associated text. As a charismatic group with deep appeal to conservationists and the public, mammals play an important …