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Many species have been increasingly recognized as an aggregate of individual dietary specialists. Previous work has emphasized the importance of individual dietary specialization in driving many ecological processes, but less is known about the relationship between individual diet and habitat use. We used data from 7 cougars and 331 predation events collected in western Colorado from 2010 to 2013 to test whether intraspecific variation in cougar (Puma concolor) diet resulted from chance encounters or from targeting particular prey species. One cougar within our study population (P06) selected for American beaver (Castor canadensis) more than expected based on availability, spent a disproportionate amount of time within beaver habitat, and exhibited reduced travel speeds when near waterways. Our results present evidence that specialist diets in predators are likely reflective of additional differences in foraging behaviors rather than random encounters with prey species (e.g., prey availability).

In recent decades, an increasing number of highway construction and reconstruction projects have included mitigation measures aimed at reducing wildlife-vehicle collisions and maintaining habitat connectivity for wildlife. The most effective and robust measures include wildlife fences combined with wildlife underpasses and overpasses. The 39 wildlife crossing structures included along a 90 km stretch of US Highway 93 on the Flathead Indian Reservation in western Montana represent one of the most extensive of such projects. We measured movements of large mammal species at 15 elliptical arch-style wildlife underpasses and adjacent habitat between April and November 2015. We investigated if the movements of large mammals through the underpasses were similar to large mammal movements in the adjacent habitat. Across all structures, large mammals (all species combined) were more likely to move through the structures than pass at a random location in the surrounding habitat. At the species level, white-tailed deer (Odocoileus virginianus) and mule deer (O. hemionus) used the underpasses significantly more than could be expected based on their movement through the surrounding habitat. However, carnivorous species such as, black bear (Ursus americanus) and coyote (Canis latrans) moved through the underpasses in similar numbers compared to the surrounding habitat.

We reviewed all North American radiotelemetry studies of within-home-range habitat selection by northern goshawks (Accipiter gentilis) and all studies relating territory occupancy and productivity to landscape habitat features. Goshawks selected habitats in the home range with structural characteristics of mature to old-growth forests, such as large trees and high canopy closure. We documented selection of these structures in a number of forest types, including ponderosa pine (Pinus ponderosa), mixed conifer, lodgepole pine (P. contorta), temperate rainforest, upland hardwood, and boreal forest, suggesting that goshawks are selecting forests for their structure rather than for species composition. Goshawks did not select stands with the greatest prey abundance. Selection for natural openings, edges, and stand diversity was inconclusive. Habitat selection patterns suggest that current goshawk management plans in the western United States may be inadequate.

Eyespots (color patterns resembling eyes) are present in many taxa and often have important ecological functions. In some taxa, potential functions of eyespots have not been extensively examined, as is the case with pygmy-owls (Glaucidium spp.), many of which bear a conspicuous eye-like pattern on their nape. Using wooden replicas of Northern Pygmy-Owls (G. gnoma), with and without eyespots, we tested one potential function: whether eyespots affect mobbing behaviors of small forest birds. We measured the orientation of mobbing behaviors (where birds perched and flew at the model) and intensity of mobbing bouts (duration of bouts and number of mobbing individuals). Eyespots affected the most proximal behavior, close passing (flights directly at the model, resulting in an approach within 0.5 m). When eyespots were present, mobbers shifted away from eyespots, providing the first empirical evidence for a link between eyespots and avian mobbing.

Citizen science programs that record wildlife observations on and along roads can help reduce the underreporting of wildlife-vehicle collisions and identify and prioritize road sections where mitigation measures may be required. It is important to evaluate potential biases in opportunistic citizen science data. We investigated whether the opportunistic observations of live animals by volunteers along a 46-km section of Highway 3 in the Crowsnest Pass area ("Road Watch in the Pass" data collection program) in Alberta, Canada, had a similar spatial pattern as systematically collected data by the researchers along the same road section. A permutation modeling process that compared the number of observations between the two datasets for each 1-km segment, a randomization method that tested for and compared hotspot observation locations, and a bivariate Ripley's L1.2-function analysis along a continuum of spatial scales all showed spatial agreement between the two datasets. There was spatial agreement at a scale between 1 and 4 km, and three clear hotspots of wildlife observation activity were identified for both processes. This suggests that the data collected by the volunteers are reliable and robust enough to be used to help identify road sections that may require mitigation measures. In addition, volunteers proved to be able to collect a sufficient number of observations relatively quickly. Within one year, 24 volunteers collected 640 wildlife observations, and we found that using only 150 or more of these observations always resulted in spatial similarity with the systematic observations collected by the researchers. We conclude with recommendations for other citizen science data collection programs and for further research. Language: en

Integration of ecological principles into private land-use planning is critical to preservation of biodiversity and functional ecosystems in the United States. Ecologists need to play an active role in shaping land-use decisions to meet those goals. Four areas of action for ecologists are (1) educating members of the staff, planning board, and governing body involved in land-use decisions; (2) serving on a planning commission or governing body; (3) commenting at public hearings; and (4) participating in citizen review panels for land-use laws and policies. The most effective measures will be those that integrate ecological principles into arguments based on the existing standards for comprehensive planning and subdivision review.