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We investigated variation of fish assemblages in response to environmental factors using Long Term Resource Monitoring Program data. Data were collected from 1993 to 2000 from five physical habitats in the unimpounded upper Mississippi River. We captured 89 species composing 18 families. Of these, 26% were fluvial specialists, 25% were fluvial dependent and 49% were generalists. The numerically dominant component of the adult fish assemblage (species accounting for >10% of total catch) accounted for 50% of the assemblage and was comprised of only three species: gizzard shad (Dorosoma cepedianum: 25%), common carp (Cyprinus carpio; 15%) and channel catfish (Ictalurus punctatus; 10%). The dominant component of the YOY fish assemblage was comprised of only two species, which accounted for 76% of the total catch: freshwater drum (Aplodinotus grunniens; 39%) and gizzard shad (37%). We used a cross-validation multivariate approach to explore how adult and young-of-the-year (YOY) assemblages varied with respect to physical habitat and environmental gradients. Furthermore, we were interested how the fish assemblages changed over time. Partial canonical correspondence analyses (pCCA) demonstrated significant effects of physical habitats. Such effects differed between young-of-the-year and adult fishes. The four main environmental gradients influencing overall assemblage structure for both age groups were river elevation, water velocity, conductivity and depth of gear deployment. Morisita's index revealed similar adult assemblage structure over time. However, the YOY assemblage present in 1995 was dissimilar from assemblages present during the other years. We speculate this is a lag effect from the backwater spawning episodes (floodpulse) that occurred with the 500-y flood in 1993. Shannon-Weiner diversity and Camargo's evenness indices were low, but stable across years for the adult assemblage, but wafted across years for the YOY assemblage.

Numerous theories have been developed and tested to explain the high botanical diversity in tropical forests, ranging from nonequilibrium theories emphasizing the importance of chance to equilibrium theories depicting highly specialized species occupying narrow ecological niches. Niche-based theories have most often evaluated species adaptation to different light environments, but some studies have evaluated the importance of edaphic attributes in controlling species distributions. We evaluated the role of edaphic factors in controlling the distribution of African mahogany in the genus Entandrophragma on a 100-ha plot in the Dzanga-Sangha Dense Forest Reserve, Central African Republic. This study went beyond simple characterization of edaphic conditions in topographic or other classes to test for specific associations with chemical and physical soil parameters known to be important to plant growth. Trees [greater than or equal to] 30 cm dbh of the four species of Entandrophragma evaluated were non-randomly distributed in the forest. Torus translation tests indicated that norte of the species exhibited any topographic preferences. However, three of the four species had significant associations with at least two soil chemical attributes. Randomization tests evaluating links between soil chemical and physical properties and topographic position underscored the complexity of the relationship and suggest that inferring edaphic attributes from broadly and simply defined habitat classes may significantly underestimate the importance of soil heterogeneity in contributing to species coexistence. Keywords: African mahogany; available phosphorus; Central African Republic; coexistence; dispersal limitation; Entandrophragma; exchangeable cations; habitat preference; niche; soil fertility; topographic position; tropical forest.

Serotiny is a key life history trait in fire-prone habitats that is favored in plants that experience stand-replacing tires within their average life span. Although variation in fire frequency has been the focus of most studies attempting to understand variation in serotiny among populations and species of plants, other factors can select against serotiny. One agent in particular that can select against serotiny is an efficient pre-dispersal seed predator that eats a large fraction of the seeds held in the canopy. To test whether selection by such a predator selects against serotiny, we compared levels of serotiny in fire-adapted Rocky Mountain lodgepole pine (Pinus contorta ssp. latifolia) in five ranges lacking its dominant pre-dispersal seed predator, the pine squirrel (Tamiasciurus hudsonicus) to 344 stands with pine squirrels. Where pine squirrels were absent, the frequency of serotiny was consistently near 100%, whereas where squirrels were present, the frequency was variable, rarely approached the high levels found in areas without squirrels, and averaged much less than 50%. This indicates that squirrels select against serotiny and that, in the absence of squirrels, the frequency of serotiny would probably be uniformly higher throughout much of the Rocky Mountains. Because serotiny levels also influence the density of seedlings following a fire, squirrels, by selecting strongly against serotiny, have the potential to alter the early stages and perhaps the course of succession and various community attributes. Keywords: fire-prone habitats; keystone species; life history evolution; lodgepole pine; pine squirrel; Pinus contorta; Rocky Mountains; seed predation; selective agent,' serotiny; stand-replacing fires; Tamiasciurus hudsonicus.

Species diversity at the local-community scale can be altered by numerous factors, including disturbances, predators, and resource levels. Intermediate levels of these three factors are predicted to enhance coexistence and diversity. However, no study has examined how these factors may interact to alter community composition. The protozoan and rotifer community that colonized containers set in a forest was used to examine the interactions between these local community processes. We conducted a fully factorial microcosm experiment that manipulated disturbance frequency, predator density, and resource levels to examine protozoan and rotifer richness, community composition, and species abundance. Species richness was significantly altered by disturbances and predators, while predator densities interacted with disturbances and resources. Total abundance was significantly affected by each treatment, as well as a disturbance and predator interaction. We found that community composition was altered by each of the treatments and their interactions, indicating that different groups of species were present depending on the treatments. These results indicate that strong species sorting occurs in this community. Understanding these factors alone and in concert can provide insight to the potential complexities that underlie community structure and species composition. Keywords: Aedes albopictus; container community; desiccation; disturbance; diversity; phytotelmata; predation; protozoa; resource addition; species composition.

Following the progressive expansion of human populations, the number of artificial habitats is increasing in shallow waters of urbanised coastal areas. The comparison of assemblages between natural and artificial habitats is necessary to determine whether there is real loss and fragmentation of natural habitats. This study investigates the changes in intertidal assemblages caused by marinas for tourists, along exposed rocky shores on the north-west coast of Italy. Marinas, being made of transplanted boulders and by internal wave-sheltered seawalls, introduce different types of artificial habitats in a relatively small area. Intertidal assemblages on breakwaters, seawalls and adjacent rocky shores were compared at three locations, thousands of metres apart. To assess the generality of patterns through time, natural and artificial habitats were sampled at three different times, over a period of about 2 years. Data were analysed by means of multivariate and univariate analyses to test the hypotheses that assemblages and abundances of single taxa differed among habitats, consistently among locations and times of sampling. Furthermore, the variability of assemblages at the scales of tens of centimetres and metres was compared among habitats. Assemblages on seawalls were largely distinct from those on rocky shores or breakwaters. Seawalls, which supported a smaller number of species than breakwaters and rocky shores, were dominated by encrusting algae and lacked common species such as Rissoella verrucosa and Patella rustica. The abundance of main-space occupiers did not differ between breakwaters and rocky shores, but there were differences in variability of assemblages at both the spatial scales investigated. This study provides evidence for differences between intertidal assemblages supported by artificial habitats at marinas and those on adjacent rocky shores. Differences in habitat-structure (and/or wave-exposure in the case of seawalls) could explain the occurrence of distinct intertidal assemblages. Despite the nature and magnitude of these differences, varied according to the type of artificial habitat considered, neither breakwaters nor seawalls could be considered surrogates of rocky shores.

Safe sleeping sites may be a limited resource crucial for survival. In order to investigate their potential significance for social organization in nocturnal primates, we analyzed the spatial distribution of daily sleeping sites, their characteristics, their usage, and sleeping group compositions in the nocturnal Milne Edwards' sportive lemur during a 6-month field study in the dry deciduous forest of northwestern Madagascar. Sexes did not differ either in body size or in body mass. Sleeping sites were used almost exclusively by adult male-female pairs. Individuals showed a high sleeping-site fidelity limited to 2-3 different sleeping sites in close vicinity during the whole study period. Most females showed a higher fidelity to one distinct sleeping site than their male partners. Sleeping groups consisted of one adult male and one adult female and remained stable in composition over the whole study period. Exclusive pair-specific usage of sleeping sites suggests sleeping site related territoriality of male-female pairs, perhaps influenced by inter- and intrasexual resource competition. Results give first insights into the distribution patterns and social organization of this species. They imply dispersed monogamy for the Milne Edwards' sportive lemur, with sleeping sites as a potentially restricted and defendable resource. Am J Phys Anthropol 122:251-258, 2003. KEY WORDS behavioral ecology; morphology; social system; evolution; lemur; Madagascar

Habitat loss might be one of the primary reasons for the decline of the swift fox (Vulpes velox) in the western Great Plains of North America. From 1998 to 2001, we monitored 42 swift foxes in a landscape interspersed with native short-grass prairies, nonnative grasslands enrolled in the Conservation Reserve Program, irrigated agricultural fields, and dry-land agricultural fields. Survival estimates ranged from 0.52 to 0.66 for both adults and juveniles, and the primary causes of death were vehicle collisions (42% deaths) and coyote (Canis latrans) predation (33%). Annual home-range size was similar for males and females (10.8 and 10.5 k[m.sup.2], respectively). Within the study area, swift foxes selected only short-grass prairies and had lower-than-expected use or complete avoidance of all other habitat types. Our results indicate swift foxes are more specialized in habitat selection than other North American canids; thus, protection of native short-grass prairies might be necessary for their long-term existence. Key words: habitat use, home range, survival, swift fox, Texas, Vulpes velox

Hydrothermal vent environments and the biological communities that populate them have been studied and described at various levels, ranging from the physiological processes of individual organisms to the biogeography and the evolution of the hydrothermal vent fauna.

Tropical deforestation is a progressive process resulting in the conversion of rain forest into a mosaic of mature forest fragments, pasture, and degraded habitat. Understanding the long-term effects of habitat fragmentation on tropical plant community structure is critical to predicting how alterations to the landscape will impact tropical biodiversity. The objective of this study was to examine fragmentation effects on the composition, abundance, and species richness of epiphyllous (leaf-inhabiting) bryophytes. I conducted this research in an experimentally fragmented forest reserve in central Amazonia where data on the distribution and abundance of 65 bryophyte taxa were analyzed from 16 1-ha sample plots located in continuous forest and fragments. Epiphyll communities inhabiting small (1- and 10-ha) fragments exhibited lower species richness, abundance, and among-site compositional variation than those from 100-ha fragments and continuous forest plots. Reduced epiphyll diversity in small fragments is not simply a statistical artifact of low epiphyll densities, but rather due to a disproportionate loss of regionally common taxa. In contrast, rare taxa responded marginally to fragmentation, and in most cases were more abundant in fragments than in continuous forest habitat. Because epiphyllous bryophytes rapidly establish species-rich communities on spatially discrete habitat patches, they are an ideal plant group for addressing the long-term (multigeneration) impact of habitat fragmentation on plant communities. Key words: Amazon rain forests; bryophytes; community structure; epiphylls; habitat fragmentation; rarefaction; reserve design.

The wolverine (Gulo gulo) is an uncommon, wide-ranging carnivore of conservation concern. We evaluated performance of landscape models for wolverines within their historical range at 2 scales in the interior Northwest based on recent observations (n = 421) from Washington, Oregon, Idaho, and Montana. At the subbasin scale, simple overlays of habitat and road-density classes were effective in predicting observations of wolverines. At the watershed scale, we used a Bayesian belief network model to provide spatially explicit estimates of relative habitat capability. The model has 3 inputs: amount of habitat, human population density, and road density. At both scales, the best models revealed strong correspondence between means of predicted counts of wolverines and means of observed counts (P < 0.001). Our results can be used to guide regional conservation planning for this elusive animal. Key words: Bayesian models, carnivores, conservation planning, Gulo gulo, habitat evaluation, interior Columbia Basin, models, Northwest, roads, wolverine

The European rabbit (Oryctolagus cuniculus) is a key prey species in Mediterranean ecosystems and is ecologically plastic. However, ecological responses of rabbits to different habitats are poorly understood. We present data on abundance, distribution, activity, and survival in 3 neighboring habitats in southwestern Spain differing in refuge and forage availability. Scrubland presents dense cover but low forage abundance; grassland offers little protective vegetation but high food availability; the ecotone provides intermediate levels of both resources. Rabbits reached the highest abundance in ecotone, whereas low food and refuge availability seemed to limit their abundance in scrubland and grassland, respectively. In scrubland, rabbits were dispersed among the cover. In grassland, rabbits were linked to aggregated burrows. In ecotone, rabbits dug burrows in the bordering bushes that abutted grassy feeding pasture. Predation by raptors was low in scrubland, and mortality due to mammalian carnivores was higher in spite of more diurnal rabbit activity. Carnivore predation also caused higher mortality in grassland, where rabbits were more nocturnal. In ecotone, the effect of both mammalian carnivores and raptors on rabbits was similar. Mortality by disease seemed to be linked to level of rabbit aggregation. Key words: abundance, activity, habitat structure, Mediterranean ecosystem, Oryctolagus cuniculus, predation exposure

Corridor effects on population densities and habitat use of 3 small-mammal species were assessed during 1998-2000 in an experimentally fragmented landscape. Corridor presence did not have a statistically significant effect on population densities of cotton rats (Sigmodon hispidus) or cotton mice (Peromyscus gossypinus); however, a significant effect was observed for old-field mice (Peromyscus polionotus) during 2000. Cotton rats were captured more frequently than expected in corridors, while old-field mice were captured more frequently than expected in habitat-patch interior; and cotton mice exhibited a more uniform distribution across habitat types. These results suggest that landscape fragmentation and habitat structure may have varying effects on population densities of different species. Key words: corridor, fragmentation, habitat use, matrix, patch, Peromyscus gossypinus, Peromyscus polionotus, Sigmodon hispidus

The recent decline of Golden-winged Warblers (Vermivora chrysoptera) correlates with the loss of suitable nesting habitat, range expansion by Blue-winged Warblers (V. pinus), and eastward expansion of Brown-headed Cowbirds (Molothrus ater). Multivariate statistics were used to examine effects of those factors on Golden-winged Warbler reproduction in north central New York. Herb and shrub cover were positively correlated with clutch size. Blue-winged Warbler proximity was negatively correlated with Golden-winged Warbler clutch size. Tree cover and perhaps herb cover, after adjusting for brood size, correlated with a reduced number of Golden-winged Warbler fledglings. Herbaceous cover correlated with a greater number of cowbird eggs in Golden-winged Warbler nests. Cowbird parasitism correlated with a reduction in the number of Golden-winged Warbler eggs incubated and proportion of incubated eggs that hatched. However, cowbird parasitism, after adjusting for brood size, did not significantly affect nestling success rate. Cowbirds parasitized 30% of Golden-winged Warbler nests, which reduced the number of Golden-winged Warblers fledged by ~17%. Average herb and tree cover values were 69 and 22 in Golden-winged Warbler territories and 60 and 23 in Blue-winged Warbler territories, respectively, with herb cover significantly greater for Golden-winged Warblers. Territories in the earliest stages of succession used by Golden-winged Warblers supported larger clutches and a reduction in the strong, negative effect of Blue-winged Warbler proximity and an increase in the negative effect correlated with cowbirds, if cowbirds were locally abundant. Received 10 January 2002, accepted 23 October 2002.

Predicting animal populations over time often is done using models of density--habitat relationships that assume animal density is a reflection of habitat quality. We explored whether this assumption was true for the North American red squirrel (Tamiasciurus hudsonicus), a species present at different densities in 3 conifer habitats: white spruce (Picea glauca; high resource quality, unstable availability), mixed conifer, and lodgepole pine (Pinus contorta; lower resource quality, stable availability). We documented density, body condition, survival, reproduction, and turnover in these 3 habitats during a failure of spruce-cone crop, when the potential for the relative importance of habitats to change was greatest. During this time squirrel densities in white spruce decreased by 66% to match with those found in pine and mixed-conifer forests. Red squirrels in spruce forests experienced lower survival and fewer females successfully weaned young, and juvenile production was lower. Adult and juvenile immigration was more important than local juvenile production in replacing squirrel mortality in spruce and mixed-conifer forests. Our results indicate that density does not always reflect habitat quality for red squirrels, and we question the historical high-quality rating of white spruce habitat for this species. Further, our findings suggest that movement of ostensibly highly territorial adults in late winter and early spring is an important mechanism in determining annual squirrel densities regardless of habitat type. Key words: demography, habitat quality, resource availability, Tamiasciurus hudsonicus, white spruce, wildlife-habitat models

Research has been conducted on the sexual size demorphism in ungulates. The hypothesis that the relationship between food dispersion, habitat use and social behavior affect the sexual demorphism in body size via sexual selection has been tested using the phylogeny of the ungulates species and the results are reported.

Radiotracking studies of Townsend's big-eared bat (Corynorhinus townsendii) were conducted in grazed grassland and coastal forest (California bay, Douglas-fir, and redwood) at Point Reyes National Seashore in coastal central California. Radiotagged bats were used to determine the foraging patterns of both female and male bats and to locate alternate roost sites. The animals showed considerable loyalty to their primary roost sites even though the study was conducted after the nursery period had ended, when the bats would normally be dispersing for the season. Foraging patterns differed between male and female bats, with females traveling greater distances than males. Males consistently stayed close to the maternity colony both during day and night. Both sexes flew in the immediate vicinity of vegetation, both when foraging and when traveling from the roost to foraging areas. Foraging activity was concentrated primarily along the edges of riparian vegetation. Key words: bat, Chiroptera, Corynorhinus townsendii, foraging, habitat use, radiotelemetry, roost sites

We used logistic regression to develop habitat models from observation of mountain goats (Oreamnos americanus) in alpine habitats near Mt. Evans, Colorado. Mountain goats used areas near escape terrain, on moderate slopes, at midelevations, and on southerly exposures more than expected. Habitat models for summer, winter, or all-seasons correctly classified 81-83% of observations and incorrectly classified 12-13% of locations not used by mountain goats. A model based only on distance to escape terrain correctly classified 87% of observations and classified 38% of the study area as suitable habitat. Our models provide a way to use readily available data and simple techniques to quickly identify suitable habitat over large geographical areas. Key words: escape terrain, geographical information system, habitat model, logistic regression, mountain goat, Oreamonos americanus

Between May 1995 and June 1999, we studied denning ecology of 81 barren-ground grizzly bears (Ursus arctos) equipped with satellite radio-collars within a study area of 235,000 k[m.sup.2], centered 400 km northeast of Yellowknife, Northwest Territories, Canada. All dens were located on well-drained slopes ([bar]X = 25.3 [degrees], SE = 1.20, n = 55). Choice of den aspect was nonrandom ([chi square] = 12.4, d.f. = 3, P < 0.01, n = 56); the majority of dens faced south (25), followed by west (13), east (10), and north (8). Most dens were constructed under cover of tall (> 0.5 m) shrubs (Betula glandulosa and Salix), the root structures of which supported ceilings of dens. Selection of denning habitat by bears was significantly different from random (G = 127.67, d.f. = 6, P < 0.0001). Bonferroni confidence intervals indicated that esker habitat was selected more than expected by chance (P < 0.10). Den entrance occurred primarily in last 2 weeks of October. The majority of bears emerged from dens in the 1st week of May. Key words: Arctic, den ecology, grizzly bear, habitat use, Northwest Territories, Nunavut, radio telemetry, resource development, Tundra

Nest-site selection behavior is a maternal effect that contributes to offspring survival and variation in offspring phenotypes that are subject to natural selection. We investigated nest-site selection and its consequences in the snapping turtle, Chelydra serpentina, in northwestern Illinois. We evaluated nest-site selection at both the microhabitat and habitat patch levels. Turtles selected nest sites with shorter vegetation, more open sand, and fewer cacti than random locations. These microhabitat characteristics described sandy patches where both nest density and success were higher compared to grassy patches in 1999. We subsequently investigated nest-site selection within two discrete subdivisions of the study area that varied in the degree of human disturbance to determine if nesting behavior, nest success, or nest temperatures were affected. The tendency to nest in sandy patches was much stronger at the natural site due to habitat modifications at the residential site that have blurred the distinction between sandy and grassy patches. Additionally, the residential site had a high density of nests within 5 m of houses and a fence (both areas with disturbed habitat similar to sandy patches), compared to the overall density. Thus, nest success associated with sandy patches may be compromised at the residential site; an ecological trap may result in lower nest success in areas with preferred microhabitat characteristics. Despite a similar basis for nest-site selection in terms of microhabitat characteristics at both sites, nest temperatures were correlated with microhabitat characteristics used to select nest sites only at the natural site. Nest temperatures at the residential site were instead correlated only with the percentage overstory vegetation cover and therefore averaged 2 [degrees] C lower than at the natural site, a temperature difference that influenced offspring sex. The higher percentage overstory vegetation cover at the residential site was due to human alterations of the habitat, and may serve to extend the ecological trap biasing the sex ratio of this population. This study illustrates the importance of (1) nest-site selection as a substantive maternal effect, (2) understanding habitat use during crucial life-history events, and (3) the potential for human disturbance to modify offspring phenotypes and negatively impact nest success despite adaptive nesting behavior. Key words: Chelydra serpentina; ecological trap; human-altered habitat; maternal effects; microhabitat; Mississippi River shoreline, Illinois; nest microenvironments; nest-site selection; offspring survival; turtles.

Research is presented concerning the nest site selection criteria of the cavity-dwelling ant in captivity. The size of the entrance, the volume of the cavity and the shape of the cavity were found to be important factors.

A new study investigates whether the provision of artificial nesting cavities in managed cottonwood forests enhances breeding bird densities.

The invasion of exotic plant species in California's southern San Joaquin Valley has created an almost impenetrable habitat for some ground-dwelling vertebrates. It is argued that managed livestock grazing could reduce such exotic species and allow at-risk populations of native animals and grasses to be sustained.

This article discusses the decline in Chinese alligator populations due to the conversion of its wetland habitats to rice farms. Topics include species extinction, habitat loss, and wildlife conservation.

We examined shelter and maternity dens used by 97 adult female polar bears (Ursus maritirnus) in relation to conditions of sea ice. Obligate use of maternity dens for pregnancy, birth, and lactation varied little with latitude or area. In contrast, timing of facultative use of shelter dens switched from autumn in the southern area (75 degrees N). For the southern area, 13 of 16 female polar bears used shelter dens in autumn versus winter (median dates of entry and exit, 11 September and 2 November; total = 56 days), whereas in the northern area, 11 of 17 bears used shelter dens in winter versus autumn (median dates, 24 December and 2 March; total = 65 days). Difference in facultative use of shelter dens was associated with conditions of sea ice. Southern regions had no sea ice when polar bears used shelter dens. In contrast, northern areas had more constant ice conditions that included presence of ice throughout the year. Southern regions seem to have greater primary productivity and more seals as a result of a pronounced seasonal cycle of annual ice. Polar bears in northern areas responded to the more constant ice conditions and less productive environment with use of shelter dens during the period with lowest seal accessibility.

We determined characteristics of nest trees and surrounding habitats used by northern flying squirrels (Glaucomys sabrinus) in subboreal forests of northwestern British Columbia during winters 1996 - 1997 and 1997 - 1998. Nineteen radiocollared flying squirrels (12 males, 7 females) were located in 82 daytime nests. Animals used an average of 5.6 nest trees (+/-0.5 SE; range, 3-10) per animal. Core nest areas used by flying squirrels averaged 2.74 +/- 0.62 ha in size; areas were more variable for males (range, 0.86 - 8.58 ha) than females (range, 0.03 - 2.23 ha). Nest trees were highly variable, suggesting that animals select more for suitable nest sites than for tree size: diameter at breast height was 16.7 - 79.0 cm, age was 42 - 174 years, and height was 11.2 - 32.7 m. A significant proportion of nest trees, however, were larger, older, and taller than trees that were randomly available in the locale of nest trees. Variation in habitats used by flying squirrels in the subboreal spruce (Picea) zone of British Columbia is evidence of the ability of this animal to occupy a wide range of conditions in a region that is not typified by old-growth forests.

We surveyed abandoned mines, caves, and bridges to identify habitat preferences of day-roosting Townsend's big-eared bat (Corynorhinus townsendii) in northern Utah. Of 820 sites surveyed (676 mines, 39 caves, and 105 bridges), 196 (23.9%) were occupied by C. townsendii. Caves were the most frequently used type of roost (84.6%), 21.2% of abandoned mines were used as day roosts, and no bridges were used. Bats occupied mines and caves at lower available elevations (1,350 - 2,440 m), which were associated with sagebrush-grass steppe, juniper woodlands, and mountain brush vegetation. In general, roosts with single low (

We investigated how white-nosed coatis (Nasua narica) cope with the extreme seasonality of a Mexican tropical dry forest by studying their activity, home ranges, and habitat selection in relation to climatic seasonality. From November 1994 to March 1997, we radiotracked 7 solitary adult males and 11 bands of females and juveniles. Males extended their activity more into night hours, were more active in both the dry and the wet seasons, and traveled a greater daily distance during the wet season than groups of coatis. Average total home range was 383.0 ha +/- 32.86 SE and did not differ between sexes. Home ranges differed seasonally only in groups that used areas during the dry season that were twice as large as those used during the wet season. Three major habitats that differed in phenology were used by coatis. Both males and groups preferred arroyo forest to dry forest and semideciduous forests. These results illustrate the importance of behavioral traits that permit coatis to have access to habitats where sparse resources (e.g., food and water) are more available as a mechanism to cope with climatic seasonality. Our study provides a basis for design of management and conservation strategies for the Chamela-Cuixmala Biosphere Reserve. The population of coatis in this reserve may be considered as a model to predict the type of behavioral responses that other populations of coatis may use to cope with climatic seasonality in other tropical dry forests throughout M6xico and Central America.

The Siberian flying squirrel (Pteromys volans) is a herbivorous, nocturnal, and arboreal rodent living in boreal coniferous forests. Home-range sizes, movements, and nest-use behavior of Pteromys were studied by radiotelemetry in southern Finland in 1996-1998. Thirty-seven animals were tracked. Average home-range size measured by 100% minimum convex polygons was 59.9 ha for males and 8.3 ha for females. Both sexes concentrated their activities in core areas that represented 9% and 11% of the home-range areas in males and females, respectively. Home ranges of males and females were several times larger than predicted according to body mass. Similarly, home ranges of Pteromys were much larger than in other gliding herbivores. Males especially showed great mobility; the average distance moved from the nest at night was 292 m, and the longest distances recorded were >2 km. A plausible explanation for the large home ranges and great mobility of Pteromys is its gliding ability; both sexes can reach distant parts of the home range for foraging, and males also can reach distant parts for receptive females. Pteromys had several nests, both cavities and dreys (nests in branches of trees), which they changed frequently.

In order to reverse the decline in numbers of the endangered red-cockaded woodpecker in the southeastern United States, greater knowledge is required of it's habitat requirements. Research developing of a model of habitat quality for the species in the North Carolina Sandhills is presented.

The feasibility of using the presence or absence of Roosevelt elk sign to identify elk habitats is evaluated and shown to be a reliable, inexpensive and easy-to-learn technique to measure the presence of elk.

The Arabian wolf (Canis lupus arabs) is a desert-adapted canid that occurs throughout arid regions in the Middle East. We examined group size, home range, habitat selection, and dispersal of Arabian wolves in the southern Negev Desert. We investigated the degree of association between wolves and human habitats. Arabian wolves had extensive dispersal distances (50-200 km). Annual survival rate of adults was 81%, but mortality caused by humans was considerable. Size of foraging group and home range were smaller than generally reported for wolves elsewhere. Arabian wolves in the Negev Desert foraged more than expected in the vicinity of human agricultural settlements. Key words: Canis lupus, Arabian wolf, survival, home range, foraging group, Israel

Many insights into community ecology over the past 3 decades were derived from investigations of associations of rodent species with microhabitats. Nonetheless, studies of microhabitat use of rodents are inconsistent, suggesting spatially dependent interacting factors. We investigated the relative ability of microhabitat and macrohabitat to predict rodent captures in traps placed in 48 trapping grids of 90 traps each during spring and autumn of 1993 and 1994 (17,280 data points). Trapping grids represented eight replications of six discrete macrohabitats. We used discriminant function analysis and random null models to compare the ability of microhabitat and macrohabitat to predict use of individual traps by 13 rodent species. Classification rates for presence at a trap by dummy variables of macrohabitats exceeded those obtained with principle components of microhabitats for nine of 13 species. In seven of those cases, classification rate exceeded that expected from a random distribution of dummy variables. Of the four cases where principle components of microhabitats out-classified dummy variables of macrohabitats, only two exceeded rates expected from a random distribution of dummy variables. Thus, microhabitat partitioning for many species is constrained by local macrohabitat conditions. Key words: small mammals, Chihuahuan Desert, New Mexico, microhabitat, macrohabitat, spatial scale

Few aspects of how forest management influences the activities of bats in the Pacific Northwest are understood. A new study investigates the effects of thinned and unthinned forest stands in Western Oregon on bat activity. The theory that bat activity levels would differ in stands of different structure is explored. The study concludes that thinning young forest stands may benefit bats by creating a habitat that they can use more effectively. However, there is high use of old-growth forests which are also important bat habitats.

Artificial nesting structures are commonly used to increase waterfowl production in the US and Canada. Among the species that readily use artificial nests are common goldeneyes, hooded mergansers and mallards. A study of nesting structure usage in 1995 in Manitoba, Canada, reveals the use of artificial nesting boxes by redheads, birds which commonly show a strong preference for emergent vegetation as nesting sites. It is suggested that the redheads' use of artificial nests was a result of limited nest cover in emergent vegetation, which was extensively flooded during the year in question. The discovery may provide a new management tool for nesting redheads.

There is an overabundance of white-tailed deer in many urban and suburban areas, but lethal methods to control deer populations are often opposed. A controlled experiment in the Sea Pines residential area of Hilton Head Island undertook to capture deer with rocket nets and mark them with radiotransmitter collars. Some deer were relocated to a forest preserve with some released at their capture site. Relocated deer were subject to greater mortality from capture-related causes, and it was concluded that live-capture and relocation was ot viable.

Experiments were performed to test the hypothesis of habitat imprinting as a mechanism in European cuckoo, Cuculus canorus, for finding an appropriate host. Each of the five artificial habitats used consisted of a pair of zebra finches as a host. Results showed that hand-reared cuckoos spent significantly more time searching for their respective familiar habitats than at other habitats in 1 of 2 test years, indicating a habitat imprinting.