Subspecific affinities, determination of population boundaries, and levels of population connectedness are of critical importance for the development of management and conservation planning. We used variation at a mitochondrial locus and 5 biparentally inherited nuclear loci to determine partitioning of genetic variation of western big-eared bats (Corynorhinus townsendii) within and among caves occurring in a fragmented landscape of gypsum deposits in western Oklahoma. To accomplish this objective, we first performed a phylogenetic analysis based on the mitochondrial locus of western big-eared bats from a large portion of their range. This analysis indicated that western big-eared bats at the periphery of the distribution in western Oklahoma share phylogenetic affinities with the most geographically restricted subspecies, C. t. pallescens. Because C. townsendii is rare in Oklahoma and is listed as a species of special concern, this finding provides additional support for the continued protection of this species in Oklahoma. Within western Oklahoma, we failed to detect significant differentiation among any caves for the biparentally inherited microsatellite data. However, the mitochondrial locus exhibited significant levels of genetic differentiation among caves, with the highest level of differentiation occurring between caves within the disjunct distributions of gypsum (Φ_ST = 38.76%). Although a significant amount of genetic differentiation was detected between populations on the 2 disjunct distributions of gypsum deposits, Analysis with the program Migrate suggested high levels of asymmetric gene flow among some populations. Our results provide a greater understanding of the population dynamics of western big-eared bats on the periphery of their range and highlight the importance of continued monitoring and study of this taxon.

We describe a new species of flying fox of the genus Desmalopex from Mindoro Island, Philippines. Discrete and mensural morphological characters distinguish the new species from other flying foxes in Southeast Asia. The new species shares several probable morphological synapomorphies with Desmalopex leucopterus, including features of the pelage, patagia, dentition, and cranium, suggesting that the 2 species are closely related. We present phylogenetic analyses of mitochondrial DNA sequences, which support the taxonomic status of the new species and the recently revalidated genus Desmalopex. Together, D. leucopterus and the new species form a well-supported clade that may be sister to Pteropus Acerodon, or perhaps more distantly related to these genera. Discovery of the new species highlights the need for continued biodiversity inventories in the Philippines, where new taxa are being discovered at a remarkable rate.

Pocket gophers of the genus Geomys are common inhabitants of many habitats throughout most of the state of Nebraska. Because the taxonomic history of Geomys has undergone numerous changes through the years, these pocket gophers have been the subjects of ongoing taxonomic and distributional studies and in more recent years genetic studies to understand relationships among populations. In order to gain deeper insight into the relationships among these taxa of Geomys, we intensively collected specimens from areas where chromosomal races were thought to form contact zones. Results from examination of genetic (chromosomes, mitochondrial cytochrome-b gene sequences, and nuclear interphotoreceptor retinoid-binding protein gene sequences), morphometric, and pelage coloration data revealed 2 areas of hybridization between taxa of Geomys in Nebraska. The 1st of these corresponded to the Oakdale vicinity in Antelope and Madison counties in northeastern Nebraska and the 2nd corresponded to Lincoln County in southwestern Nebraska. The taxonomic implications of our study support the recommendations from earlier studies performed in other areas of the geographic range of Geomys. Specifically, in Nebraska we recognize 3 species: G. bursarius majusculus in eastern Nebraska, G. lutescens in the Sand Hills and adjacent areas of central and western Nebraska, and G. jugossicularis halli in southwestern Nebraska. The exact geographic distributions and relationships of these species within Nebraska and the surrounding states remain to be determined in detail.

Spalacopus cyanus is a subterranean rodent inhabiting coastal and mountain habitats. Individuals from mountain populations are larger than individuals from the coast, and mountain populations have a more limited geographic range. To investigate the genetic structure and biogeography of this species, we analyzed mitochondrial DNA control region sequences. We found low levels of nucleotide diversity in comparison with other subterranean rodents. Coastal populations had higher nucleotide diversity and effective population size than mountain populations. Phylogenetic analysis using maximum parsimony and a haplotype network generated using statistical parsimony recognized 3 groups of haplotypes: northern coastal and mountain populations, central coastal populations, and southern coastal population. Consistent with the presence of unshared haplotypes, migration rates were practically 0, except from Valparaíso to Ventanas and from La Parva to Huentelauquén. We observed asymmetric migration rates from mountain to coastal populations, suggesting that this species originated in the Andean mountains. A likelihood ratio test could not reject the null hypothesis of a stable population when all sequences were grouped into a single population and when coastal populations were analyzed separately. However, a negative exponential growth parameter was estimated for mountain populations, suggesting that these populations have undergone recent demographic changes.

Phyllomys is the most diverse genus of the subfamily Echimyinae, and is represented by 12 described species endemic to the Atlantic forest of eastern South America. We name and describe a new species of Phyllomys based on specimens collected in southern Brazil. This species is closely related to P. dasythrix and has been referred to as “Phyllomys aff. dasythrix” in the literature. Chromosomal restructuring was probably involved in their speciation because genetic and morphological similarities of the 2 contrast with their karyotypic distinctiveness. The new species of Phyllomys is diagnosed by a unique combination of external, cranial, and karyotypic characters. We propose the conservation status of “Least Concern” for Phyllomys sp. nov., but “Vulnerable” for P. dasythrix. We present an identification key to the living species of Phyllomys.

For squirrels, physical size varies with ancestry, locomotion, and sex. Body length has little variation associated with subfamilies or tribes but varies significantly among genera within tribes. Thus, patterns in body size among genera represent more recent evolutionary pressures. Flying squirrels weigh less than similarly sized tree or ground squirrels but ecological profile and ancestry are confounded for flying squirrels. Tail length has clear relationships with ecological profile in squirrels. Tail length is shorter in ground squirrels, longer in tree squirrels, and longest in flying squirrels. In addition, in arboreal squirrels, females have longer tails, relative to body length, than those of males. This latter result suggests that reproductive constraints can influence external features of morphology.

The contribution of indirect fitness to inclusive fitness is expected to increase as the reproductive skew increases, with indirect fitness being the only component of inclusive fitness of sterile individuals in eusocial species. However, the relative contribution of indirect fitness to inclusive fitness has rarely been evaluated empirically. Using data from a long-term study (1962–2003), we show that female yellow-bellied marmots that have a later age of 1st successful reproduction incur a substantial loss of direct fitness with no corresponding gain in indirect fitness. Additionally, although females that survive to reproductive age but do not successfully reproduce have a greater indirect fitness than those that reproduce at least once, indirect fitness benefits of foregoing reproduction are insufficient to compensate for the loss of direct fitness resulting from later reproduction. Although indirect fitness composed 22.2% of the inclusive fitness of females that reproduced at least once, females that reproduced at least once had 2.3 times higher inclusive fitness than those that survived to reproductive age but never reproduced. These results suggest that, in yellow-bellied marmots and other species with similar life histories, the contribution of indirect fitness to inclusive fitness does not compensate for loss of direct fitness.

Columbian ground squirrels (Spermophilus columbianus) usually copulate underground in a burrow. Underground copulations might be associated with 2 nonexclusive benefits: reducing probability of predation during copulation and reducing interference by conspecific males. We tested whether either of these benefits was involved in determining if the copulation site was underground or aboveground. In 2006 and 2007, we obtained detailed information on the copulatory behavior and social interactions of free-ranging individuals in southwestern Alberta, Canada. During the 3-week annual breeding period, we also recorded the activity of predators of Columbian ground squirrels such as ravens, foxes, and hawks. Squirrels that lived on the periphery of the population were more susceptible to predation than squirrels in the center. Despite this risk, aboveground copulations usually occurred on peripheral territories. In addition, aboveground copulations were not further removed in time from predator attacks or sightings than underground copulations. Copulations that occurred aboveground were sometimes disrupted by previous mates of the estrous female. Probability that copulation would occur aboveground increased when the density of reproductive males around an estrous female was low. Our results suggest that although underground copulations protect individuals from predation, male–male competition for females and interference with copulations have been more important than predation in determining copulatory sites for Columbian ground squirrels in our study population.

Alarm calls alert receivers to the presence and/or nature of a predatory threat. Studies of alarm communication in Richardson's ground squirrels (Spermophilus richardsonii) have focused on juvenile signalers and receivers; however, adult and juvenile receivers may tailor their response to alarm calls based on different underlying signal parameters and attend differentially to alarm calls broadcast by adult versus juvenile signalers. To examine the potential influence of signaler and receiver age on the perception of response urgency, we presented free-living juvenile and adult S. richardsonii with alarm calls produced by juveniles and adults. Behavioral responses of call recipients were videotaped and analyzed to determine the influence of signaler and receiver age-class. No differences in vigilance response after juvenile- and adult-produced calls were detected for either adult or juvenile receivers. At the proximate level, the absence of any detectable difference in the acoustic attributes of juvenile- versus adult-produced calls may account for the lack of differential response. The absence of any age-dependent productional difference also is consistent with the recently advanced notion of young concealing information regarding their age in their alarm signals.

Previous studies suggest that eastern chipmunks (Tamias striatus) avoid roads, but it is unclear whether vehicle traffic plays a role in this avoidance. The purpose of this study was to determine whether road avoidance in chipmunks increases with traffic. We tracked the movements of 68 chipmunks released near roads with widely varying volumes of traffic. Our results suggest that chipmunks responded to changes in traffic volume only in the preliminary stages of their movement pathways. Apart from this initial response, we found that road avoidance was independent of traffic, with evidence that chipmunks avoided both the roadside verge and the road surface. Because avoidance of roads was independent of traffic, effects of roads on populations of chipmunks may be manifest more as population subdivision than as direct mortality.

We estimated the median and maximum life spans of 1,459 spiny rats (Proechimys semispinosus) from mark–recapture data collected monthly from 4 island populations in central Panama over a 9-year period. We plotted frequency distributions of life spans of males and females over 5-month age intervals, proportions of males and females surviving versus age, and survivorship curves for males and females. Median life spans ranged from 6.5 to 10 months, and maximum life spans ranged from 36 to 53 months. Frequency distributions were skewed to the right, showing a greater frequency of individuals with shorter life spans. Life spans did not differ between sexes or among islands. Survival curves were linear for both males and females within 1 population and convex for both sexes within the other 3 populations. We thereby provided the 1st quantitative analysis of life spans and survival curves for any small tropical rodent.

Cavia intermedia is a rare cavy, endemic to the 10-ha Moleques do Sul Island, southern Brazil. We conducted the 1st study of reproductive and growth patterns for this species in its natural environment. Based on 17 months of monthly population monitoring using capture–mark–recapture methods, females were reproductively active throughout the year. Litter size was small (1 or 2 young per litter), with well-developed offspring that weighed approximately 19% of the mass of an adult female. Sexual maturity was reached later than in other species of this genus, at around 59 days of age or 70% of adult body size. There was no evidence that longevity was longer than for congeneric species. Other than longevity, these characteristics are consistent with the island syndrome, which may contribute to the persistence of this species.

We investigated the occurrence of small, ground-dwelling mammals (marsupial mice and rodents) across 128 forested study sites representing a stratified sample of the climatic, geological, and topographic features of far southeastern mainland Australia. We then developed statistical models for the occurrence of the agile antechinus (Antechinus agilis), dusky antechinus (A. swainsonii), and bush rat (Rattus fuscipes) based on various environmental attributes measured for each site. At a landscape scale, the climatic factor mean minimum temperature of the coldest month was an important explanatory variable for the bush rat, with the likelihood of its occurrence increasing with increasing temperature during that period. Sites with greater precipitation during the driest quarter of the year were more likely to support bush rats and the agile antechinus. At an on-site scale, protected slopes and gullies were more likely to support bush rats, and the occurrence of bush rats and the dusky antechinus increased at sites with a higher number of large fallen trees. In multiple-use forests, increasing the number of large fallen trees after timber harvesting may increase habitat quality for both the dusky antechinus and the bush rat, and retaining habitat on protected slopes and gullies also may be important for the latter species.

We studied the morphology and diet of Musonycteris harrisoni, an endangered nectar-feeding bat endemic to western Mexico, and explored potential reasons for the cranial specialization of this extraordinarily long-snouted bat. We achieved 28 captures in the wet season and 30 in the dry season, which represents the largest data set in existence for this rare species. We took morphological data and collected pollen from the bats' pelage. Diet analysis revealed the genera Cleome, Pseudobombax, Crataeva, Agave, Helicteres, and the columnar cactus Pachycereus pecten-aboriginum as main food plants. We found no indication for a tight relationship between M. harrisoni and long-tubed flowers that would obligatorily require a long rostrum for exploitation, with the possible exception of the columnar cactus. However, because cacti are common food plants for many less-specialized nectar-feeding bats, the extraordinarily long rostrum might permit M. harrisoni to use the same abundant plant species as larger species while maintaining a smaller body size, therefore having lower absolute energy requirements. This in turn could facilitate a resident lifestyle in a habitat with annual resource bottlenecks. Males have significantly longer snouts (approximately 9%) than females, suggesting that rostrum length also might be influenced by intraspecific interactions or restrictions. Our favored explanation is that the rostrum length of females may be limited by stability issues, because calcium mobilization during pregnancy and lactation can considerably weaken bone structure.

Torpor minimizes energy expenditure and water loss during periods of inclement weather, low prey availability, or both, and appears especially important in harsh environments such as deserts. We investigated use of torpor by free-ranging adult male pallid bats (Antrozous pallidus) at the northern limit of their range in the semiarid Okanagan Valley in British Columbia, Canada. We predicted that males would use torpor frequently during the active season and that ambient temperature (T_a) as well as nutritional condition (body condition index [BCI]) would affect torpor use. We expected roost microclimate to be conducive to daily heterothermy given that roosts had cool morning temperatures that increased in the afternoon. We used temperature-sensitive radiotransmitters to measure skin temperature (T_skin) of 8 bats from June to August 2003. Seven individuals used torpor each day (n = 54 tracking days) but not at night. Torpor duration increased as mean daytime T_a decreased albeit the relationship differed between individuals. There was no significant effect of individual on the relationship between minimum T_skin during torpor and T_a. BCI was significantly and inversely correlated with torpor bout duration. Mean daytime temperatures in rock crevice roosts approached 30°C and fluctuated less than T_a.

Nyctalus noctula is one of the most common bats in the western Palearctic, whereas N. leisleri is relatively rare (except in Ireland, where N. noctula does not occur) and more limited to ancient forests. We radiotracked 26 N. noctula and 25 N. leisleri to 52 and 50 roost trees, respectively, from May to August in 1998–2002 in the Białowieża Primeval Forest in eastern Poland to test the hypothesis that N. leiseri has more specific tree-roosting requirements than N. noctula. Both species selected roosts at the microscale (cavity level), mesoscale (tree level), and megascale (plot level). N. noctula significantly preferred oaks, and avoided hornbeams and alders. N. leisleri roosted more often in oaks and ashes, and avoided hornbeams and alders. Roost trees occupied by both species were thicker and taller, with higher crowns than available trees. N. noctula and N. leisleri used oaks more frequently than ashes when average ambient temperatures were lower. Pregnant and lactating females of both species most often used oaks, whereas after the young could fly most roosts were in other tree species, mainly ashes. Reproductive status influenced the choice of roosts used by N. noctula, whereas both the reproductive status and ambient temperature were influential for N. leisleri. Both taxa preferred dying trees and avoided healthy ones, although N. noctula used hollows in healthy trees significantly more often than N. leisleri. In our opinion, more frequent use of healthy trees by N. noctula suggests a better ability to exploit younger, managed forests. However, differences in roost selection between these species were small.

The fragmentation of forests by the expansion of agriculture is recognized as an important factor influencing worldwide declines of forest-dependent species. Species that are forest dependent may be especially vulnerable to fragmentation because they have specialized resource requirements and may exhibit lower mobility in an agricultural matrix. We investigated movement patterns and resource selection of forest-dependent northern long-eared myotis (Myotis septentrionalis) in a forest–agricultural landscape on Prince Edward Island, Canada. Radiotelemetry was used to locate day-roosts and to estimate locations of female bats during nightly foraging bouts. Day-roost locations and foraging areas were mapped using a geographic information system to generally characterize the forest cover of foraging and roosting areas. Vegetative structure and insect prey availability were measured in the field and compared between foraging and roosting areas to describe resource selection at these sites. Movements of female northern long-eared myotis were constrained to forest features and foraging areas were concentrated along forest-covered creeks with bats roosting predominantly in deciduous trees within the same forest fragment, although bats at 1 site seemed to exclusively use a barn during late pregnancy and lactation. Differences in prey availability did not explain the spatial segregation of roosting and foraging areas. Relative to roost areas foraging sites were more likely to be close to forested creeks and densely forested areas, whereas roost sites were characterized by the availability of potentially suitable roosts. This study demonstrates the importance of investigating movements and resource selection of individuals in fragmented landscapes because a specialization on forest resources can highly restrict the vagility of forest-dependent species to a local environment.

Although importance of forested corridors to navigating and foraging bats has been documented, the relationship between corridors and roost-site selection has not been studied. From late May to mid-August 2003–2006, we used radiotelemetry to investigate roost-site selection by Seminole bats (Lasiurus seminolus) on an intensively managed landscape with forested corridors in southern South Carolina. We tracked 27 (10 males and 17 females) adult Seminole bats to 90 (41 males and 49 females) diurnal roosts. We found 61% (n = 25) of male and 63% (n = 31) of female roosts in forested corridors, which comprised 11% of the landscape. We modeled roost-site selection with logistic regression and used Akaike's information criterion for small samples (AIC_c) and Akaike weights to select models relating roost-site selection to landscape-level features. Our results indicated that several factors (i.e., distance to nearest corridor and distance to nearest mature pine stand) influenced roost-site selection and that differences existed between males and females, and among female reproductive condition. Examination of our data suggests that landscape-level features are more important than tree- and plot-level characteristics for roosting by Seminole bats on this managed forest. Corridors may represent a feasible approach to maintaining suitable roosting habitat for Seminole bats in managed forest landscapes.

The need to capture wild animals for conservation, research, and management is well justified, but long-term effects of capture and handling remain unclear. We analyzed standard types of data collected from 127 grizzly bears (Ursus arctos) captured 239 times in western Alberta, Canada, 1999–2005, and 213 American black bears (U. americanus) captured 363 times in southwestern North Carolina, 1981–2002, to determine if we could detect long-term effects of capture and handling, that is, effects persisting ≥1 month. We measured blood serum levels of aspartate aminotransferase (AST), creatine kinase (CK), and myoglobin to assess muscle injury in association with different methods of capture. Serum concentrations of AST and CK were above normal in a higher proportion of captures by leghold snare (64% of 119 grizzly bear captures and 66% of 165 black bear captures) than capture by helicopter darting (18% of 87 grizzly bear captures) or by barrel trap (14% of 7 grizzly bear captures and 29% of 7 black bear captures). Extreme AST values (>5 times upper reference limit) in 7 (6%) grizzly bears and 29 (18%) black bears captured by leghold snare were consistent with the occurrence of exertional (capture) myopathy. We calculated daily movement rates for 91 radiocollared grizzly bears and 128 radiocollared black bears to determine if our activities affected their mobility during a 100-day period after capture. In both species, movement rates decreased below mean normal rate immediately after capture (grizzly bears: X̄ = 57% of normal, 95% confidence interval = 45–74%; black bears: 77%, 64–88%) and then returned to normal in 3–6 weeks (grizzly bears: 28 days, 20–37 days; black bears: 36 days, 19–53 days). We examined the effect of repeated captures on age-related changes in body condition of 127 grizzly bears and 207 black bears and found in both species that age-specific body condition of bears captured ≥2 times (42 grizzly bears and 98 black bears) tended to be poorer than that of bears captured once only (85 grizzly bears and 109 black bears), with the magnitude of effect directly proportional to number of times captured and the effect more evident with age. Importantly, the condition of bears did not affect their probability of capture or recapture. These findings challenge persons engaged in wildlife capture to examine their capture procedures and research results carefully. Significant capture-related effects may go undetected, providing a false sense of the welfare of released animals. Further, failure to recognize and account for long-term effects of capture and handling on research results can potentially lead to erroneous interpretations.

The spatial organization of a species on a landscape is influenced, at least in part, by the presence of sympatric competitors. Interspecific relationships can thus have direct effects on the carrying capacity of the landscape and have important implications for conservation. We investigated the spatial relationships and activity patterns of 2 similarly sized mustelids: the invasive American mink (Neovison vison) and the native European polecat (Mustela putorius) in lowlands in the United Kingdom. By radiotracking mink (n = 11) and polecats (n = 7) in autumn when individuals of both species hold stable home ranges, we found that individuals tended to have overlapping home ranges, both within and between species; and the size of overlap areas was similar, but generally small, within and between species (mean approximately 20%, although overlaps were higher among mink of opposite sexes). Mink shared their home ranges with 0.3–1.17 other mink (of both sexes) and 0.83–1.3 polecats; polecats shared their home ranges with 0.6–1.0 polecats (of the opposite sex) and 1.6–2.0 mink. Neighbors avoided simultaneous use of overlap areas; polecats were nocturnal and mink were predominantly diurnal. Our results are consistent with interspecific territoriality although we cannot distinguish between interspecific territoriality and niche differentiation. We suggest that there is habitat partitioning between the 2 species, but that this is incomplete and that temporal partitioning enables avoidance of interspecific neighbors within overlap areas. Niche partitioning by distance from water and time of day when active probably facilitates coexistence in the short term, but it is unclear whether coexistence is stable year-round or in the long term.

Previous studies have suggested that diets of river otters (Lontra canadensis) vary in response to seasonal shifts in prey availability, and that they select slowly moving fish of moderate size. To test these assumptions for marine-coastal river otters in Newfoundland, Canada, we reconstructed diets and estimated body length of important fish prey through analysis of otoliths and other hard parts recovered from scats collected in Bonavista and Placentia bays. Diet of otters in Bonavista Bay also was compared with the species and size composition of the nearshore fish community, as determined by concurrent beach-seine sampling. Diets were qualitatively similar but quantitatively different between bays. Otters consumed proportionally more cunner (Tautogolabrus adspersus) and stickleback (Gasterosteidae) in Placentia Bay, and more sculpin (Cottidae) and cod (Gadus) in Bonavista Bay. Flounder (Pseudopleuronectes americanus) was important in both bays, based on biomass, because individual fish in the diet were large. Fish-community composition in Bonavista Bay varied seasonally, a pattern that was not reflected in the diet, suggesting active selection of fish prey by otters. Slow-swimming fish (sculpin, flounder, and ocean pout [Macrozoarces americanus]/rock gunnel [Pholis gunnellus]) were overrepresented in the diet, and fast-swimming species (cod and hake [Urophycis]) were underrepresented. Otters also selected larger individuals within taxa. The lower limits at which size classes were incorporated into diet varied across fish species, and may reflect species differences in detectability by otters due to camouflage and behavior.

The seasonal diet of Pampas foxes (Lycalopex gymnocercus) was examined from 431 scat samples collected during 1 year in the dry Chaco woodland of Salta Province, northwestern Argentina. Fleshy fruits dominated the diet during the dry and wet seasons, representing 69% of the total frequency and comprising 91% of the total volume. Most of the fruit diet was contributed by 5 woody plant species. Mistol (Ziziphus mistol, Rhamnaceae), was the most important fruit resource throughout the year. Arthropods (particularly beetles and scorpions) and small mammals (mainly rodents and marmosets) were the most frequently consumed animal prey. Seasonal shifts in the frequency of the main food items in the diet were not significant, but there was considerable seasonal variation in the frequency of fruit species. Diversity of prey in the diet was highest in the wet season. The Pampas fox is a generalist feeder that can alter its diet to changes in food availability. However, its diet in the Chaco, which is dominated by fruit, differs from its diet in Pampas grassland habitat, where it consumes mostly meat.

Mammalian chewing rate scales inversely to body mass (M); however, controversy exists over the value of the scaling exponent. Different mechanisms explain different values of the scaling exponent; hence, a better estimate of the exponent would provide insight into the mechanisms governing chewing rate across mammalian species. We evaluated the relationship between mean chewing cycle duration (CD; i.e., the inverse of mean chewing rate) and M in 132 species and removed phylogenetic effects by using an independent contrast method currently used in evolutionary biology studies. A one-third–power law resulted when independent contrasts were not used; however, a one-third– to one-fourth–power law resulted when independent contrasts were used to remove phylogenetic effects. We hypothesize that variation in the scaling exponent is due to natural selection acting to increase metabolic efficiency; and variation in the complexity of mandibular kinematics, motor control asymmetry, and mandibular biomechanics, which may act to increase CDs above the “ideal” one-fourth–power law. Future studies should consider effects due to jaw-movement kinematics, motor control issues, and biomechanics.

Animals alter resource use as conditions change and these changes could have significant consequences on demography. We generated a logistic resource selection probability function for habitat use and estimated percent composition of diets by pronghorn (Antilocapra americana) in Yellowstone National Park during winter to assess if selection of sagebrush (Artemisia) has changed since the 1960s, corresponding with diminishing sagebrush and increasing seral species such as rabbitbrush (Chrysothamnus). We located 37 radiocollared adult females in 1,440 different groups during December 1999 through March 2005 and compared habitat attributes to 9,347 randomly selected points from the winter range. Pronghorn preferred greasewood (Sarcobatus vermiculatus) and selected grasslands in comparison to the sagebrush cover type. The relative selection against sagebrush may stem from a substantial decrease in this plant type on the winter range by the 1960s due to intense browsing by congregated ungulates. The percent composition of sagebrush in the winter diets of pronghorn decreased from 67% during 1985–1988 to <10% during 2000–2001, while rabbitbrush increased from 5% to 60%. These findings and the results of companion time-series analyses suggest the winter range for Yellowstone pronghorn may not support larger populations (>500) of pronghorn for sustained periods, as occurred historically. Similar effects from habitat fragmentation and degradation face managers of migratory ungulates worldwide.

Use of licks influences the movements and distribution of ungulates. We recorded attendance patterns, duration of visits to licks, and time spent licking by 4 ungulate species at wet and dry licks to examine possible influences on the timing of use of licks in northern British Columbia, Canada. Within-species licking intensity (based on regressions between time spent licking per visit and duration of visits to licks) was higher for elk (Cervus elaphus) than for moose (Alces alces) at wet licks, and higher for mountain goats (Oreamnos americanus) than for Stone's sheep (Ovis dalli stonei) at dry licks. Lick response variables (duration of visits to licks, time spent licking per visit, and proportion of time spent licking) did not vary significantly among early, mid-, and late summer seasons, but there were species-specific differences in the timing of highest attendance. High use of wet licks by both female and male elk in late May followed vegetation greening at low elevations. Average attendance by female elk was highest in late June, coinciding with high lactation demands. Attendance by moose at wet licks was highest in mid-July, potentially coinciding with other aspects of forage phenology such as increased plant defensive compounds. Attendance by Stone's sheep and mountain goats at dry licks was high in early July, following forage change at high elevations and again in early August, potentially related to the trade-off between lactation demands and predation risk. Across species, consumption of lick soils allows ungulates to improve rumen function and nutrient absorption during the transition to spring and summer forage and to supplement elemental intake by females during the nutritional stress associated with lactation.

Although seabirds frequently aggregate with feeding delphinids, the benefits to seabirds of feeding with dolphins have been rarely reported. We examined how dusky dolphins (Lagenorhynchus obscurus) influenced prey accessibility for seabirds in Admiralty Bay, New Zealand. Interactions of dusky dolphins and seabirds were characterized during 335 feeding bouts of dusky dolphins (52 video-recorded underwater). Dolphins increased prey accessibility for seabirds because they swam under the bottom half of prey balls for 59% of passes that were within 2 m of the prey ball. During feeding bouts by dolphins, 51% of prey balls ascended, whereas only 13% descended. Dolphins also influenced prey mobility; only 24% of stationary feeding bouts became mobile after dolphins began feeding, and 17% subsequently became stationary again. Significantly more Australasian gannets (Morus serrator) were near mobile than stationary prey balls after feeding, but not during feeding bouts. This suggests that feeding gannets increase mobility of prey balls, but that feeding dolphins counteract this effect. Seabirds also used dusky dolphins to locate prey. Numbers of gannets, shearwaters (Puffinus), and gulls (Larus) increased during the first 2 min of dolphin feeding, even when other seabirds were not present. Gannets fed with dolphins for 40% of gannet feeding observations and shearwaters fed with dolphins for 24% of shearwater feeding observations.

California sea lions (Zalophus californianus) in the Gulf of California have declined by 20% over the past 2 decades. The lack of data on life-history parameters for this species has limited the development of demographic models to assess the status of this population. We estimated age- and sex-specific annual survival probabilities for California sea lions using resighting data on 5 pup cohorts from 1981 to 2006. We modeled apparent survival and resighting probability using age-class, sex, and time as potential explanatory variables. Apparent survival rates varied for different age- and sex-classes. Only survival of pups varied by year (from 0.556 to 0.998). Survival was the same for immature males and females (0.90), but differed by sex for young (males = 0.90, females = 0.97) and old (males = 0.75, females = 0.91) adults. Resighting probabilities varied by time, age-class, and sex. Resighting probabilities were higher for females than for males, and lowest for juveniles. The survival estimates presented here provide practical insight into understanding age- and sex-specific survival rates for California sea lions.