A gravel quarry near Edmonton, Alberta, Canada, yielded remains of micromammalian taxa not previously reported in the mid-Wisconsinan (late Pleistocene) interstadial “local fauna.” A left M1 and an upper incisor fragment of Lemmus trimucronatus and a left M2 of Dicrostonyx groenlandicus were recovered. These finds represent the 2nd Pleistocene record for Lemmus in Alberta, the 3rd for Dicrostonyx, and the 1st for both taxa from a northern Great Plains site. They help to fill distributional gaps between Beringia and the midcontinent. In association with those of large grazing megaherbivores, these new arvicoline finds support the inference of a cool, fairly dry steppe in central Alberta during the last interstadial.

Molecular phylogenetic relationships were investigated in 6 species of Chinchillidae (Chinchilla lanigera, C. brevicaudata, Lagidium peruanum, L. viscacia, L. wolffsohni, and Lagostomus maximus), 1 species of Dinomyidae (Dinomys branickii), 1 of Abrocomidae (Abrocoma cinerea), and 1 of Octodontidae (Octodon degus) using the first 548 base pairs of the mitochondrial cytochrome-b gene. Maximum-parsimony and maximum-likelihood analyses consistently showed Chinchillidae as a robust clade and confirmed a close relationship with Dinomyidae. Both Chinchilla species differed at 22 sites, and 3 were nonsilent; average genetic distances were approximately 6%. Sequences from domestic C. lanigera and wild C. brevicaudata showed low levels of variation. Although all topologies obtained were congruent with current taxonomy, Lagidium exhibited large genetic distances (range 5.9–8.9%), suggesting the existence of more than the 3 species currently recognized.

DNA sequences obtained from the mitochondrial cytochrome-b gene were used to evaluate phylogenetic relationships among 15 genera of putative neotomine–peromyscine rodents. Tree topologies obtained from maximum likelihood and Bayesian analyses revealed 4 primary clades that, in general, conform to the 4 tribes proposed by Carleton (1980). The Peromyscini (Megadontomys, Ochrotomys, Osgoodomys, Peromyscus, and Reithrodontomys) was sister to the Neotomini (Hodomys, Neotoma, Onychomys, and Xenomys). These 2 clades were then joined by the Baiomyini (Baiomys and Scotinomys) and Tylomyini (Nyctomys, Ototylomys, and Tylomys). The most apparent departure from previously proposed arrangements involved the placement of Onychomys in the Neotomini instead of the Peromyscini.

Phylogenetic relationships among 8 species of white-toothed shrews (Crocidurinae, Mammalia) in East and Central Asia were evaluated based on mitochondrial cytochrome-b gene sequences. The taxon formerly regarded as Crocidura suaveolens in East Asia phylogenetically is distinct from that of true C. suaveolens in Europe, suggesting that specimens in East Asia should be considered a distinct species, C. shantungensis. All shrews from Central Asia were regarded as C. sibirica, although phylogenetic comparison with the unsampled C. gmelini is needed to confirm its taxonomic status. C. shantungensis, C. suaveolens, and C. sibirica formed a well-supported monophyletic group. C. dsinezumi, C. lasiura, C. kurodai, and C. watasei also formed a well-supported monophyletic group. Within C. dsinezumi, there were 2 clusters, referable to western and eastern Japan. Based on low genetic divergence, C. dsinezumi on Cheju and Hokkaido islands appear to be the result of a recent introduction from western Japan and northern-eastern Honshu, respectively.

A combination of 1,140 base pairs of the mitochondrial cytochrome b gene of Platalina, Lionycteris, and several species of Lonchophylla (Chiroptera: Phyllostomidae) with 150 morphological, sex chromosome, and restriction site characters were used in an attempt to resolve relationships among the lonchophylline taxa. In addition, the monophyly of Lonchophylla was tested, particularly with respect to Platalina. The most parsimonious hypothesis of relationships using all available characters was (L. mordax ((L. chocoana (L. robusta, L. handleyi))(L. thomasi (Lionycteris, Platalina)))). Lonchophylla appears to be paraphyletic, but this arrangement is not well supported. Our analyses suggest that Platalina is not simply a large Lonchophylla, as had been suggested by previous morphological analyses. The low support values for basal relationships found in this study are probably caused by saturation in cytochrome b 3rd positions. Additionally, 2 alternative explanations are viable (if improbable): unsampled lonchophyllines are necessary to confidently resolve relationships at the base of the group, or the lack of resolution at the base of the lonchophylline phylogeny might be explained by rapid speciation following the separation from other glossophagines. Future work examining the phylogenetic relationships of lonchophylline bats should focus on describing new taxa, obtaining tissue samples from unsequenced representatives, and adding nuclear loci to this mitochondrial DNA data set.

Temperature sensors were placed in the abdominal cavity, on the neck, and outside the dens of 5 hibernating black bears (Ursus americanus) during early winter and removed at the end of winter before emergence of bears from their dens. Bears did not arouse from torpor throughout the winter test period. Abdominal temperature remained within a 1.5°C temperature range and did not appear to exhibit circadian rhythmicity. However, neck surface temperature of bears demonstrated elevated spikes from 2 to 30°C about 4 times each day. Adult students wearing the same neck sensors as bears exhibited similar spikes in body surface temperature when vigorously exercising in the cold. We suggest that bears engage in bouts of muscle activity during the winter denning period that may result in the retention of muscle strength without elevating their core body temperature and without arousing from torpor.

Latrine behavior, or the preferential, repeated use of 1 or more specific defecation sites, is well known among mammals and believed to function in olfactory communication among individuals or groups in many circumstances. Primates have reduced their capacity for olfaction in favor of more developed visual systems; however, several prosimian primates regularly use olfactory communication for transmission of social signals, most often using scent gland secretions and urine. Latrine behaviors have been described rarely in primates and have traditionally not been included in reviews of primate olfactory communication, yet we found ample evidence that certain primate species habitually use latrine sites for defecation. Here we review the previous evidence for latrine use in primates and report new and more extensive observations of latrine use in 2 lemuriform primates (Lepilemur sp. and Hapalemur griseus). Based on these new observations, we present and evaluate 4 available hypotheses for the function of latrines (advertisement of sexual cycling, predation avoidance, intragroup spacing, and intergroup resource defense) in lemur taxa for which sufficient evidence of latrine use exists. In all cases, intergroup resource defense is the function most consistent with available observations.

Sex-biased maternal investment involves differential allocation of resources to production and rearing of sons or daughters as a function of their anticipated reproductive output. We examined reproductive investment among captive giraffes (Giraffa camelopardalis) over a 21-year period to determine extent to which females invest differentially in offspring by sex. We found an unbiased sex ratio at birth and comparable interbirth intervals following rearing of either sons or daughters. Early neonatal mortality compressed interbirth interval and females probably conceived while lactating. We suggest that females invest equally in sons and daughters because males surpass females in size subsequent to the period of infant dependency.

Demography and spatial patterns of free-ranging American mink were documented by continuous year-round trapping and radiotracking along 24 km of the River Thames in England, United Kingdom. An estimated average of 7.19 ± 0.58 SE minks per month were present between May 1995 and August 1997. Kit and juvenile paternity was assessed using 7 microsatellite markers and we observed evidence that multiple paternity occurred in this population. Although males maintained territories during most of the year, they sired litters in areas beyond their territory boundaries. We suggest that a male's inability to monopolize paternity, along with a female's ability to continue ovulation after successful matings (i.e., superfetation) explains why males abandon territoriality during the breeding season. We suggest that the main function of a brief delayed implantation of this species may be to enable female mink to retain superfetation, which facilitates the fertilization of ova from different ovulations by different males. This mink model, consisting of disarticulating residency from fatherhood and the possibility of superfetation, may occur more widely among related species and requires a re-evaluation of mustelid sociobiology.

We present results of a radiotracking study of the black-tailed tree rat Thallomys nigricauda, based on 3 males and 4 females in the breeding season and 2 males and 5 females in the nonbreeding season. The study was conducted in the southern Kalahari thornveld, South Africa, a savanna landscape of acacia trees and patchy acacia bush. Nocturnal activity patterns, vegetation use, space use, and interactions were followed for 8–17 days. During the breeding season, males were active with 2 synchronous activity peaks shortly after sunset and late at night. Home ranges included the nests of 8–10 females, 6 different daytime resting places, and 3–5 areas of high activity. Males were mobile within home ranges of 5–10 ha (90% minimal convex polygons) that overlapped with other males and covered home ranges of several females. Activity of females was high shortly after sunset and before sunrise with 6 h of low activity between. Home ranges of nursing females were 0.001–0.03 ha and included 2 small areas of high activity (nest and foraging site) where no other adult females were observed. Animals preferred small acacia shrubs (Acacia mellifera, A. luederitzi) for foraging. During the nonbreeding season, activity of both sexes was low, with only 1 peak shortly after sunset. Although small acacia shrubs did not have foliage, they were preferred by both sexes for foraging, and rats were observed feeding on buds. Home-range size of males was 1–2 ha and of females was 0.1–0.3 ha. Contrary to earlier reports, we found tree rats living solitarily or with young offspring. We suggest that the species has a promiscuous mating system.

Cranial anatomy of baleen whales was examined in order to identify evolutionary morphological novelties. Complex surfaces of the mandibles and craniums of 4 minke whales (Balaenoptera acutorostrata) were plotted in 3 dimensions by close-range photogrammetry. Photogrammetric data sets representing naturally opposed borders of the mandible and maxilla were used to determine 3-dimensional (3D) conformal coordinate transformations. These allowed the creation of precise 3D computer models of the skulls in which the strongly bowed mandibles were closely opposed along their entire length to the curved lateral borders of the rostrum. This simulated mouth closure. Subsequent internal measurements demonstrated a biomechanical specialization heretofore unknown in the class Mammalia—a maxillomandibular cam articulation. This novel articulation would operate as an adjunct to the temporomandibular joint in the final stage of mouth closure. Our functional interpretation is that it is at least a mechanism by which the energy cost of carrying a gigantic, expandable mouth at speed through an aqueous medium could be kept to a minimum. This articulation also may be part of a critically important trigger mechanism needed for precisely timed deployment of the feeding apparatus while it is under high hydrodynamic loads. We suggest that this evolutionary innovation was the root enabling cause of the adaptive radiation of rorquals (Balaenopteridae).

In this study we analyze the population dynamics of the migratory and nectarivorous Leptonycteris nivalis (Mexican long-nosed bat) in relation to food abundance and environmental factors (temperature and humidity). A 2-year study was conducted in the Mexican state of Nuevo Leon. Bat densities and the number of blooming Agave were estimated by month at El Infierno cave and surrounding areas. Temperature and humidity were recorded at 4.5-h intervals inside and outside the bat roost. Bat density was estimated visually, and the number of blooming Agave was counted in 70 fixed plots along 3 road transects within a 50-km radius of the cave. Examination of data indicates that abundance of L. nivalis at El Infierno cave is correlated with the frequency of blooming Agave and ambient temperature. However, cave temperature, humidity, and external humidity were not correlated with bat numbers. These findings suggest that conservation of this federally protected bat will require maintenance of relatively large areas of wild Agave.

I determined foods eaten by bats at Prairie Creek, Vigo County, Indiana, to test the null hypothesis that insectivorous bats eat primarily whatever is available. If bats eat what is available, then all bats taken at the same time and place should eat the same foods. I collected fecal samples from 486 bats of 8 species from 1993 through 1997 in a 650-ha deciduous forest in the Wabash River flood plain. Eptesicus fuscus and Nycticeius humeralis fed heavily on coleopterans, followed by hemipterans in E. fuscus and homopterans in N. humeralis. Lasiurus borealis fed most heavily on lepidopterans, followed by coleopterans and homopterans. Pipistrellus subflavus fed approximately equally on homopterans, coleopterans, and dipterans. The main foods were similar for Myotis sodalis, M. lucifugus, and M. septentrionalis: dipterans 1st, followed by lepidopterans, trichopterans, and then coleopterans in M. lucifugus and by coleopterans and then lepidopterans in the other 2 species. It is clear that bats at Prairie Creek selected from among the available foods. Myotis septentrionalis, a gleaner, did not eat foods appreciably different from other bats in the same genus.

American martens (Martes americana) and fishers (M. pennanti) occur together in mixed-conifer forests of the southern Sierra Nevada. We studied their diets in the area of sympatry by examining their feces and comparing diet diversity and overlap. Diets of both species were more diverse than previously reported in North America. Although the diet of fishers appeared to include more remains of birds, lizards, hypogeous fungi, and insects than that of martens, the rank contribution of prey items to the diets did not differ and the Pianka index of dietary overlap was high. The great diversity of diets of fishers and martens may be due to the absence or rarity of large prey (e.g., snowshoe hares [Lepus americanus] and porcupines [Erethizon dorsatum]) or to a greater diversity of available prey types in the southern Sierra Nevada compared to other study sites for Martes in North America. The high degree of overlap in diets is surprising given the body size differences between martens and fishers, previously described differences in their diets, and similar use of other niche dimensions. The similarity is probably due, in part, to the relatively large pool of diverse and available resources that are exploited by both species by using similar modes of foraging. In addition, our sample of martens was drawn from the lowest margin of their elevational range in the southern Sierra; a more comprehensive survey of the diets of martens at higher elevations may yield different results.

We determined the diet of the brown-nosed coati (Nasua nasua) in an urban semideciduous forest fragment in southeastern Brazil. Coati feces were collected weekly for 3 years. The 226 fecal samples included plant parts (85.4%), insects (75.7%), millipedes (53.9%), fruits (48.7%), spiders (33.6%), organic waste (9.7%), vertebrates (9.3%), and gastropods (2.6%). More spiders and millipedes were consumed during the wet season, and more fruits were consumed in the dry season. The consumption of vertebrates, fruits, and millipedes differed among different years. The monthly consumption of spiders and millipedes was positively correlated with rainfall. The consumption of fruits was negatively correlated with the consumption of millipedes and insects. Fruits were an important resource during periods of arthropod scarcity. Coatis ingested and defecated intact seeds of 49 plant species, indicating that they can be important seed dispersers. The consumption of vertebrates was occasional and varied.

Abundance and distribution of food resources can profoundly affect movements and spatial distribution of solitary carnivores. Food availability and distribution are often altered in urbanized systems due to occurrence of abundant and highly concentrated anthropogenic resources. To address effects of these resources on movements and spatial distribution of raccoons (Procyon lotor), we simultaneously studied populations inhabiting urban (Ned Brown Forest Preserve), suburban (Max McGraw Wildlife Foundation), and rural (Glacial Park) open areas in northeastern Illinois. Estimates of sizes of home ranges were smaller for urban (range, 25.2–52.8 ha, n = 29) and suburban (21.4–37.2 ha, n = 34) than rural (71.2–182.4 ha, n = 39) raccoons during all seasons (P < 0.05). Seasonal changes in sizes of home ranges were least pronounced at the suburban site. Seasonal shifts in activity centers also were small for raccoons at the suburban site and for most raccoons at the urban site. Spatial distribution was aggregated during all seasons at the urban site, and during all seasons except summer 1997 at the suburban site. Abundant and relatively stable artificial resources typical of urbanized systems contributed to reduced size and increased stability of home ranges. Further, concentration of these resources into rich and separated patches resulted in an aggregated distribution. Similar responses to abundant and concentrated resources have been documented for solitary carnivores in other, more natural, systems.

We investigated the effect of refuse feeding on body condition, reproductive success, and survival in banded mongooses (Mungos mungo). Data were collected from 231 mongooses in 3 refuse-feeding groups and 311 mongooses in 8 non–refuse-feeding groups within Queen Elizabeth National Park, Uganda. Refuse-feeding adults were heavier and in better physical condition than non–refuse-feeding adults. Refuse-feeding females carried more fetuses than non–refuse-feeding females, but no difference was found in conception rate, number of emerging young, or number of independent young per female between refuse-feeding and non–refuse-feeding females. Male young in refuse-feeding groups had higher mortality than all other young. These findings show that for this social carnivore, access to garbage dumps had significant but contrasting effects on components of fitness but no overall effect on evolutionary fitness.

We retrospectively tested whether differences in activity patterns and foraging efficiency by males and females were responsible for sexual segregation in mule deer (Odocoileus hemionus). These deer spatially segregated by sex during the dry season (May–October), which encompassed parturition, and aggregated during the wet season (November–April), which included rut. Activity did not differ among types of social groups of deer (mixed-sex, adult male, or adult female), but was greater during the dry season than in the wet season. Foraging efficiency (percentage of active deer feeding) was greater in mixed-sex groups than in groups of either adult males or adult females during both wet and dry seasons. We rejected the hypothesis that differences in activity or foraging efficiency lead to spatial segregation of the sexes in mule deer; no aspect of that hypothesis will explain why sexes use space or other resources differentially. We propose a new approach that incorporates niche theory and reconciles past difficulties in how best to interpret sexual segregation in ungulates.

We used global positioning system (GPS) radiocollars on female white-tailed deer (Odocoileus virginianus) to document details of onsets of migrations, rates of travel, patterns of travel, durations of migrations, and distances traveled by 8 deer in spring and 4 deer in autumn in northeastern Minnesota in 1998, 1999, and 2001. In spring, deer migrated 23–45 km during 31–356 h, deviating a maximum 1.6–4.0 km perpendicular from a straight line of travel between their seasonal ranges. They migrated a minimum of 2.1–18.6 km/day over 11–56 h during 2–14 periods of travel. Minimum travel during 1-h intervals averaged 1.5 km/h (SD = 0.6, n = 27). Deer paused 1–12 times, averaging 24 h/pause (SD = 29, n = 43, range 19–306 h/pause). Deer migrated similar distances in autumn with comparable rates and patterns of travel. A difference of 1.9- to 7.5-fold in duration of migrations by deer migrating the same distances suggests that much of the variation in durations may be independent of migration distance.

A lack of quantitative information on life history of the western gray squirrel (Sciurus griseus) has hampered conservation and management efforts across its range. We report on data from 21 squirrels radiotracked in Klickitat County, Washington, from 1998 to 1999 to examine the interaction between home-range size, sex, and season. Home-range estimates were calculated by using minimum convex polygon and fixed kernel methods. Only adult animals with ≥40 relocations were included in total home-range comparisons. Estimates of 95% minimum convex polygon home range in Washington averaged 73.0 ha for males (n = 9) and 21.6 ha for females (n = 12) for year-round use, significantly larger than those from Oregon and California. Differences in home-range size of males and females were significant. Fixed kernel and minimum convex polygon estimates were similar in size. We suggest that near the northern limit of the species' geographic range low species richness, low abundance, and a patchy distribution of mast-producing vegetation result in large male and female home ranges, low overlap of female home ranges, and a sparsely distributed squirrel population.

Using radiotelemetry, we studied home range and movements of 32 adult female and 16 adult male Mohave ground squirrels (Spermophilus mohavensis) in the western Mojave Desert of California during 1990 and from 1994 to 1997. In 3 of the 5 years of study (1990, 1994, and 1996), early winter precipitation (October–January) was <30 mm, and no reproduction occurred at the study site. Postmating home ranges of females varied considerably among years, with annual medians for minimum convex polygons ranging from 0.29 to 1.90 ha. Females used the largest home ranges both during years of ample rainfall and reproduction (1995 and 1997) and during the year of most extreme drought and no reproduction (1990). We hypothesize that variation in home-range size among drought years may result from varying levels of food availability. In 1997, we also studied movements of adults during the mating season, from mid-February to mid-March. During this period, adult males made extensive movements, resulting in median minimum convex polygons much larger (6.73 ha) than those of females (0.74 ha). Such movements would have made it possible for males to locate adult females soon after their emergence from hibernation. Patterns of variation in home-range size and movements observed during this study may reflect adaptive responses of this small herbivore to a highly variable, arid environment.

Analysis of pellets of Tyto alba and scats of Genetta genetta and Sherman livetrapping were compared to assess richness and composition of small mammal communities in a Mediterranean area (NE Spain). Owl pellets provided 17 small mammal species (17,232 individuals), genet scats 14 species (2,145 individuals), and livetrapping 9 species (1,488 individuals). Owl pellets oversampled insectivores and grassland rodents and undersampled tree-dwelling and woodland rodents. Genet scats and livetrapping oversampled woodland rodents and undersampled insectivores and grassland rodents. After controlling for sample size and elevation differences between methods by means of analysis of covariance (ANCOVA) and rarefaction, owl pellets contained higher richness for small samples (<50 individuals), and scats contained higher richness for large samples (>100 individuals), both having higher richness than livetrapping regardless of sample size. We concluded that both indirect methods provided complementary information of small mammal communities, detecting the 19 small mammal species known to be present in the study area.

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, several studies have failed to detect microhabitat partitioning, and research has consistently indicated that microhabitat phenomena do not explain larger spatial scale (i.e., macrohabitat) variation. Possible reasons for these difficult to reconcile observations are explored by reviewing and tabulating data from 70 studies. The meaning of the term microhabitat has changed subtly since 1969. This review demonstrates that the existing knowledge of small mammal microhabitat partitioning is highly concentrated among small-scale studies, conducted with modest intensity, that measure microhabitat at inappropriate spatial scales. This concentration of knowledge appears to be an insufficient foundation on which to accept microhabitat partitioning as a widely generalizable phenomenon. The observation that microhabitat phenomena do not explain larger spatial scale variation suggests the importance of underappreciated adaptive mechanisms that relate to the ability of species to coexist, use habitat, and ultimately persist.

We studied demography of the Keen's mouse (Peromyscus keeni macrorhinus) and the Wrangell Island red-backed vole (Clethrionomys gapperi wrangeli) in the Alexander Archipelago during 1998–2000 because of concerns over population viability from extensive clear-cut logging of temperate rain forest in the region. We trapped 1-ha grids and assessment lines with live traps during spring and autumn to compare populations among gap-phase old-growth, multicohort old-growth, peatland mixed-conifer, and thinned young-growth (23-year-old) forests. Generally, gap-phase old growth and peatland mixed conifer supported the highest and lowest populations of voles, respectively. One notable exception was during autumn 1998, when vole population levels were highest and density was higher (P < 0.02) in young growth than gap-phase old growth. Mean body mass, minimum summer and overwinter survival, age and sex composition, and percentage reproductive females did not differ among habitats. For Keen's mouse, density was highest in 1998; overall, populations were highest in young growth and lowest in peatland mixed conifer. Mean body mass and minimum summer and overwinter survival did not differ among habitats, but fewer reproductive females were recorded in multicohort than in gap-phase old growth, peatland mixed conifer, or young growth. Our results suggest that C. gapperi populations in southeastern Alaska are not as sensitive to canopy removal as has been indicated elsewhere in western coniferous forests and that P. keeni populations in southeastern Alaska flourish in a variety of habitats. If the results of our study can be generalized across southeastern Alaska, peatland mixed conifer likely contributes little to breeding populations of C. gapperi and thus is unlikely to mitigate any effects of broad-scale clear-cut logging of old-growth forests.

We examined long-term (1978–1999) population fluctuations and their influence on community structure in 6 species of rodents that are syntopic in old-field habitat in northeastern Kansas. Populations of all species fluctuated severalfold in abundance, with Sigmodon hispidus, Peromyscus maniculatus, and Reithrodontomys megalotis exhibiting annual cycles. Multiannual periodicities were evident for Microtus ochrogaster, P. maniculatus (3.5–4 years), and P. leucopus (7 years). Only Synaptomys cooperi lacked a discernable pattern in its abundance. Monthly abundances of 6 of 15 species-pairs positively covaried, suggesting similar responses to long-term environmental variation. In addition, several species-pairs showed time-lagged cross-correlations that indicate regular annual cycles, which were out of phase. Because of this variation in population dynamics within and among community members, the structure of this community varied considerably over time, indicating a nonequilibrial community. However, when looking at the community as a whole, 2 reoccurring long-term patterns in community structure emerge: an annual and a 3.5-year cycle. Annual cycles in community structure occurred because 3 of the 6 species showed annual cycles, whereas the 3.5-year cycle in community structure was probably due to the overwhelming influence of fluctuations in abundance of the numerically dominant prairie vole.

Long-distance movements may play an important role in regulating populations of small mammals. To examine such movements, we livetrapped 1,712 deer mice (Peromyscus maniculatus) on 14–28 permanent traplines from autumn 1981 to spring 1990 on the Konza Prairie Biological Station, Kansas. These data were collected under a variety of climatic and biotic conditions that resulted in detection of >100 long-distance movements by deer mice between traplines (moves of 50–1,320 m). Males made more moves than females, but distance moved did not differ by sex. Age did not affect the number or distance of movements. On average, more long-distance moves occurred in spring and summer than in autumn, but distance did not differ by season. Proportion of the population making intertrapline movements was inversely related to abundance of deer mice. Deer mice did not exhibit a fire-positive response in long-distance movement. Our results indicate that deer mice may be more mobile than originally thought. Researchers should incorporate improved methods for detecting longer movements to better understand causes and consequences of these movements.

Marsh rice rats (Oryzomys palustris) inhabit wetlands and occasionally occupy adjacent uplands. I hypothesized that demographic factors, environmental factors, and/or prey availability influenced their use of upland habitats. Rice rats were monitored on livetrap grids that extended from low marsh through upland habitats near Galveston, Texas. Diet was determined from fecal samples, and regression models evaluated influence of environmental factors on upland use. Density was highest in wetlands during summer and autumn and highest in uplands during winter and spring when tides were high and temperatures low. Adults were more common in wetlands, and juveniles were more frequent in uplands, whereas abundance of subadults was similar in wetlands and uplands. Rice rats ate primarily aquatic organisms and wetland vegetation in both habitats; upland plants were a minor component of the diet of rice rats in uplands. I conclude that uplands were not primary foraging areas but served as sink habitats for dispersers and as refuges during high tides. Given the highly fragmented nature of these wetlands, uplands may have significant conservation value as sinks in a metapopulation. These results support views that current laws for wetland delineation are ecologically incomplete because uplands are not protected and that buffer habitats or transitional areas adjacent to wetlands should be included in legislation and management plans.

Using resource selection functions, we examined habitat selection patterns of tundra wolves (Canis lupus) in the central Canadian Arctic at the level of the home range and within the home range. Esker habitat was relatively preferred by wolves at the home range level of selection, possibly indicating the importance of denning habitat as a limiting factor for tundra wolves. We failed to conclusively tie vegetation communities to movements of wolves within the home range. Eskers make up only about 1–2% of the landscape; hence, a potential conflict between wolf conservation and industrial development in the region may occur as eskers are targeted as a source of granular material for road construction. Results of this study underline the importance of scale dependence in habitat selection. Failure to view habitat selection as a hierarchical process may result in a narrow and possibly misleading notion of the value of habitats to animals.