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Eastern Moose (Alces americanus americanus (Clinton, 1822)) on mainland Nova Scotia (MNS) are declining and experience limited immigration across the Isthmus of Chignecto from the larger population in neighbouring New Brunswick. Provincially Endangered, the recovery strategy for MNS Moose involves mitigating various threats that may lead to local extirpation. We examine genetic diversity of MNS Moose using microsatellite markers and mitochondrial (mtDNA) control region sequences. Genetic similarities with the Alces a. americana population in New Brunswick and the introduced Northwestern Moose (Alces americanus andersoni (= Alces alces andersoni) Peterson, 1952) population on Cape Breton Island are also analysed. Observed heterozygosity for microsatellites for MNS Moose was low and there was also evidence of limited gene flow between Nova Scotia and New Brunswick across the narrow Isthmus of Chignecto that connects these provinces. Consistent with relatively recent colonization of North America by Moose dispersing across the Bering Land Bridge <15000 years ago, mtDNA haplotypes of MNS Moose were identical or extremely similar to haplotypes found across North America. However, mtDNA diversity was lower in Nova Scotia and New Brunswick than in more central regions of the species’ range. Active measures to maintain habitat that promote connectivity across the Isthmus of Chignecto would likely be valuable for Moose in terms of maintaining genetic variation in the region and reducing inbreeding. [ABSTRACT FROM AUTHOR]

Fisher (Pekania pennanti) is a medium-sized mesocarnivore that typically occupies mature hardwood and softwood forest where its preferred prey is abundant. In Nova Scotia, Fisher populations are reported as restricted to the mainland; they have been absent from Cape Breton Island for the past 50-80 years. A record of a Fisher on Cape Breton Island in February 2002 prompted us to collate and analyze other records of Cape Breton Island sightings of the species from that date to May 2021. Based on reported sightings, we conclude that Fisher has extended its range from mainland Nova Scotia, apparently crossing the Strait of Canso, and that a breeding population now exists on Cape Breton Island and is expanding. We also comment on possible negative interactions between this expanding Fisher population and the provincially Endangered American Marten (Martes americana) population on the island. [ABSTRACT FROM AUTHOR]

Identifying optimal habitat and predicting species distributions are essential components in developing management priorities for species of concern. In Nova Scotia, Canada, the breeding population of American woodcock (Scolopax minor) has been in decline over the past 50 years, likely in part because of reduced availability of habitat. We aimed to identify regions in Nova Scotia expected to support high numbers of woodcock, and whether monitoring efforts sufficiently capture the distribution of habitat. We generated a species distribution model to identify areas of highest relative predicted abundance and optimal habitat based on 15 years of standardized singing ground survey monitoring conducted along 50 routes and a candidate set of 56 habitat variables representative of composition and configuration at each of 2 ecologically relevant spatial scales (i.e., describing habitat immediately available to displaying males and the broader landscape used by the local breeding population). The species distribution model indicated extensive areas of optimal habitat in the central mainland characterized by moist organic soils, large, irregularly shaped patches of early successional forest, and large patches of open space created by developed, urban areas. We identified additional smaller pockets of habitat throughout the province likely to support relatively high local abundances. Much of the area identified as optimal habitat is not currently surveyed by singing ground survey routes. Expanding survey route coverage into regions identified as potentially optimal habitat could help clarify drivers of population declines. Overall, partnerships with provincial forest managers will be key to ensuring the maintenance of woodcock habitat while balancing the needs of a suite of avian species toward the goal of biodiversity conservation in Nova Scotia. [ABSTRACT FROM AUTHOR]

The American common eider Somateria mollissima dresseri is a sea duck of coastal mid-Atlantic North America, and breeding colonies in the southern part of its range have been in decline. To better understand threats faced by the subspecies, we used satellite telemetry to track 46 eiders through their annual cycle in four years from three regions in the southern part of the range, to identify key locations and migratory corridors. Female eiders exhibited highly variable movement phenology within and among colonies, but coastal Maine and Massachusetts were consistent, important moulting areas for males and females from all breeding colonies. Most birds wintered in coastal waters around Cape Cod and Nantucket Sound, meaning that threats in this region (industrial development, disease outbreak, harvest) could have deleterious effects on much of the population. [ABSTRACT FROM AUTHOR]

Context: This study synthesizes evidence from three separate surveys of American Black Duck and Mallard breeding habitat usage to quantify the effects of agriculture at the landscape scale.Objectives: To assess duck breeding activity in agricultural landscapes within the Canadian maritimes in order to measure the overall impact of agricultural land use, the response to particular agricultural activities, and the influence of landscape configuration.Methods: Models, constructed using a long-term census (SURVEY1), were used to predict habitat selection for two other independent surveys (SURVEY2, SURVEY3). Predictions incorporated information about wetland area and diversity, as well as anthropogenic factors, allowing subsequent analyses to focus on the remaining residual error attributable to agricultural effects.Results: SURVEY2 results demonstrated that the proportion of active agriculture is an important indicator of the severity of human disturbance, yielding threshold estimates of 39% for Mallards and 60% for Black Ducks, with an overall average of 50%. Agricultural conversion beyond these thresholds deterred breeding ducks independently of other factors. SURVEY3 land cover information demonstrated that the presence of cropland intensified this deterrence effect, even at levels as low as 10%. Woodland cover (in excess of 30%) was important for both species, but its configuration was not.Conclusions: In addition to quantifying threshold effects, this study reaffirms that woodland is an important part of the maritime landscape matrix, and contributes positively to habitat diversity in mixed use, moderate intensity agricultural regions. Wetland restoration in agricultural landscapes should monitor and promote less crop-intensive, mixed-use practices. [ABSTRACT FROM AUTHOR]