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Habitat fragmentation and genetic bottlenecks can have substantial impacts on the health and management of wildlife species by lowering diversity and subdividing populations. Population genetic comparisons across time periods can help elucidate temporal changes in populations and the processes responsible for the changes. Bobcats (Lynx rufus) are wide-ranging carnivores and are currently increasing in abundance across an expanding range. Bobcat populations in New England have fluctuated in the past century in response to changes in their prey base, harvest pressure, and landscape development. We genotyped contemporary (2010–2017) and historic (1952–1964) bobcats from New England and Quebec, Canada at a suite of microsatellite loci and tested for differences in diversity, effective population size, and gene flow. Over 20 generations separated the sampling periods, and the intervening years were marked by drastic changes in land use and species management regimes. We found a general decrease in genetic diversity and differing population genetic structure through time. Effective population size decreased at the end of the historic period, coincident with a spike in harvest, but rebounded to greater numbers in the contemporary period. Our results suggest that bobcat populations in the region are robust, but development and range dynamics may play a significant role in population structure. Our study also highlights the benefits of a historical perspective in interpreting contemporary population genetic data. [ABSTRACT FROM AUTHOR]

The New England cottontail ( Sylvilagus transitionalis) has suffered from extensive loss and fragmentation of its habitat and is now a species of conservation priority in the northeastern United States. Remnant New England cottontail populations currently occur in five geographically disjunct locations: southern Maine and southeastern New Hampshire (MENH); the Merrimack Valley in central New Hampshire (NH-MV); Cape Cod, Massachusetts (CC); parts of eastern Connecticut and Rhode Island (CTRI); and western Connecticut, southeastern New York and southwestern Massachusetts (CTNY). We used microsatellite genotyping to discern patterns of population structure, genetic variability, and demographic history across the species' range and to assess whether the observed patterns are a consequence of recent habitat loss and fragmentation. Our findings show that the geographic populations are highly differentiated (overall F = 0.145; P < 0.001). Using Bayesian clustering analyses, we identified five genetic clusters, which corresponded closely to the geographic populations, but grouped MENH & NH-MV together (ME/NH) and identified an isolated population in eastern Connecticut (Bluff Point). The genetic clusters showed little evidence of recent gene flow and are highly influenced by genetic drift. The CC and Bluff Point populations show signs they experienced a genetic bottleneck, whereas the ME/NH population shows evidence of ongoing decline. Populations in Bluff Point, CC, and ME/NH also show significantly reduced genetic variation relative to the other clusters (CTNY and CTRI without Bluff Point). Without immediate human intervention, the short-term persistence of New England cottontail populations in Maine, New Hampshire and Cape Cod is at great risk. Conservation efforts at this time should focus on within-population sustainability and eventually restoring connectivity among these isolated populations. [ABSTRACT FROM AUTHOR]

Grasslands, and species dependent on them, have been declining throughout New England since large-scale farm abandonment began in the 19th century. Several avian grassland obligates are now considered threatened within New England. During the summer of 2009, we inventoried breeding birds at the 10.5-ha National Guard training site in Stratford, NH using systematic surveys. Dolichonyx orvzivorus (Bobolinks), Sturnella magna (Eastern Meadowlarks), and Passerculus sandwichensis (Savannah Sparrows) were found breeding at the site. Bobolinks were the most abundant grassland obligate, and their nesting success on this site indicates that small grasslands may be just as useful in grassland bird conservation as larger habitat patches. Because large grasslands in New England are few and usually consist of hayfields and pasture, blueberry barrens, military and commercial airports, and landfills, focusing conservation efforts on smaller grasslands as well as large ones seems warranted. [ABSTRACT FROM AUTHOR]

Since 1960 the range occupied by New England cottontails (NEC, Sylvilagus transitionalis) in the northeastern United States has declined dramatically. Populations in some regions are known to be vulnerable to extirpation, but little was known about the status of populations in most areas. A recently conducted (2000–2004) range-wide survey identified five disjunct populations within approximately 14% of the historic range of NEC. We incorporated the results of this survey into a geographic information system to examine habitat features associated with remnant populations of NEC at two spatial scales. The regional scale characterized habitats within our survey sample units, 7.5min topographic quadrangles (quads, ∼40×10km) that were occupied by NEC or vacant. The landscape scale described habitats within a 1-km radius of occupied patches and an equivalent sample of vacant patches. At the regional scale, northeastern and southeastern populations were associated with human-dominated habitats with a greater abundance of developed and disturbed lands, less forest coverage, more edge habitats, and less snow fall than unoccupied quads. Landscapes occupied by NEC in these regions were characterized by a greater abundance of potential dispersal corridors than unoccupied landscapes. In contrast, quads occupied by NEC in the southwestern portion of the historic range were in rural areas that were dominated by forests and agricultural fields. At the landscape scale, southwestern populations were affiliated patches of habitat surrounded by more agricultural lands than patches that were not occupied by NEC. Logistic regression models were then developed to identify habitats suitable for restoration or translocation within each region. We suggest that initial restoration efforts be directed toward expanding existing populations of NEC. Next, habitat connections should be developed among these populations. Finally, new populations should then be established via translocation in portions of the historic range that are vacant. In addition to promoting New England cottontails, management of early-successional and shrub-dominated habitats in the northeastern United States will benefit other taxa of conservation concern that are dependent on these habitats. [Copyright &y& Elsevier]

The abundance and distribution of New England cottontails (NEC; Sylvilagus transitionalis) have been declining for several decades. Remnant populations in some regions are known to be vulnerable to extirpation but little is known about the status of populations in most areas. We conducted a survey of the historic range (ca. 1960) of NEC to determine the current distribution and relative status of extant populations. Because NEC were sympatric with eastern cottontails (S. floridanus) and snowshoe hares (Lepus americanus) in much of their historic range, identity of resident lagomorphs was based on DNA extracted either from tissue of captured cottontails or from fecal pellets of free-ranging lagomorphs. We searched 2,301 patches of suitable habitat and detected NEC in 162. We identified 5 disjunct populations in approximately 14% of the historic range. Forest maturation and fragmentation are the most plausible explanations for the widespread decline of NEC. Contraction of the historic distribution was toward eastern and southern edges where a variety of anthropogenic disturbances (e.g., brushy edges of highways and railroad corridors and idle portions of agricultural fields) provided habitat. Land-ownership patterns (dominated by small acreages) and land-use activities (expanding development and limited forest management) within the currently occupied range of NEC suggest a continued decline of suitable habitats. As a result, we recommend efforts to enhance remaining populations of NEC that include responses at 2 spatial scales. At the population or landscape scale, current land uses should guide habitat manipulations that expand existing populations. At the regional scale, we recommend consideration should be given to increasing dispersal among remnant populations, possibly by generating "stepping stones" of suitable habitat. In addition to improving long-term viability of NEC, other species of conservation concern that are dependent on early successional habitats will benefit from these efforts. [ABSTRACT FROM AUTHOR]