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Shellfish aquaculture is a globally expanding industry, including in urban estuaries that support non‐breeding waterfowl. The effects of shellfish aquaculture on the spatial distribution of non‐breeding waterfowl, however, are poorly understood and depend on the ecology of waterfowl and cultivated shellfish species. We investigated how proximity to shellfish aquaculture influenced habitat selection and movement patterns of American black ducks (Anas rubripes) during the non‐breeding season (~Oct–May) in 2020–2023 in Rhode Island, USA. The extent to which proximity to aquaculture influenced habitat selection of black ducks depended on factors specific to individuals' primary non‐breeding sites, although proximity to aquaculture did not have biologically meaningful influences on black duck movement rates across all sites. Black ducks across sites consistently selected for areas better suited for aquaculture (i.e., areas of potential future development) relative to areas poorly suited for aquaculture (i.e., areas less likely to be developed). The continued expansion of aquaculture into preferred black duck habitats will increase black duck interactions with aquaculture and therefore should be considered in the decision‐making process for siting future aquaculture leases. Future studies should quantify the extent to which continued expansion of aquaculture in those preferred coastal habitats directly influences black ducks. [ABSTRACT FROM AUTHOR]

Ongoing declines in the imperiled New England cottontail Sylvilagus transitionalis have coincided with the introduction and expansion of the closely related eastern cottontail Sylvilagus floridanus. These paired population trends have led to the inference of competition between the two species. Competition between native and introduced species has often involved overlapping use of food resources, but limited effort has been spent to analyze the diets of New England cottontail and eastern cottontail and to evaluate the potential for resource competition. We used microhistologic analysis of fecal pellets to assess the winter diets of both species and we compared diet composition with available plant communities to evaluate their preferences for dietary items across southern New England and southeastern New York. We found no differences in diets between New England cottontail and eastern cottontail, although diets did differ between regions within the study area. Diet preferences also were consistent between the species and largely excluded nonnative plant genera. Our results demonstrate that these species are generalist herbivores and that there is high potential for competition for food resources in the winter between them, although the present lack of diet partitioning may indicate the presence of other factors limiting competition. This study highlights the need for careful evaluation of interactions between native and nonnative species, a prerequisite for developing conservation plans that appropriately account for interspecific competition. [ABSTRACT FROM AUTHOR]

Lynx rufus (Bobcat) is a wide-ranging and highly adaptable predator whose populations are increasing throughout much of its natural range including in the New England states, yet there are only limited empirical ecological studies there. How Bobcats are responding to the unique modern landscape of southern New England with its highly forested landscape coupled with high density of humans is unknown. This lack of spatial and population ecological information impedes evaluating recovery and management objectives and identifying necessary management actions. Our objectives were to better understand the spatial and population structure of Bobcats in Rhode Island. We specifically examined space use, resource selection, and population genetics. We trapped Bobcats across 5 field seasons from April 2015 to March 2019, totaling 2232 trap nights. We captured 8 Bobcats, equipped GPS collars to a subset (n = 3), and collected locations for 4 to 9 months. We used GPS locations to estimate annual and seasonal home-range size and individual-level seasonal resource selection within the home range for each individual. Further, we used tissue samples collected from trapped individuals and opportunistically collected roadkill (n = 30) to examine the population genetic structure and effective population size of Bobcats in the state. We found the mean winter and summer home-range sizes were 219.3 km² and 51.7 km², respectively. Bobcats selected for forested wetland habitats and were associated with areas closer to wetlands and young forests, according to resource-selection models. They also selected for areas with higher road densities, yet avoided developed areas. We found that Bobcats in Rhode Island are part of 1 genetic population and estimated their effective population size to be 82 individuals (95% CI: 44--329). Our study highlights the importance of examining a widely distributed species at a local scale in order to employ evidence-based management practices. [ABSTRACT FROM AUTHOR]