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USGS2005

Broad-scale predictors of canada lynx occurrence in eastern North America

The Canada lynx (Lynx canadensis) is listed as a threatened species throughout the southern extent of its geographic range in the United States. Most research on lynx has been conducted in the western United States and Canada; little is known about the ecology of lynx in eastern North America. To fill critical knowledge gaps about this species, we modeled and mapped lynx occurrence using habitat and weather data from 7 eastern states and 3 Canadian provinces. Annual snowfall, road density, bobcat (L. rufus) harvest, deciduous forest, and coniferous forest were compared at 1,150 lynx locations and 1,288 random locations. Nineteen a priori models were developed using the information-theoretic approach, and logistic regression models were ranked using Akaike's Information Criterion (AIC) and by our ability to correctly classify reserved data (Kappa). Annual snowfall and deciduous forest predicted lynx presence and absence for a reserved dataset (n = 278) with 94% accuracy. A map of the probability of lynx occurrence throughout the region revealed that 92% of the potential habitat (i.e., >50% probability of occurrence) was concentrated in a relatively contiguous complex encompassing northern Maine, New Brunswick, and the Gaspe?? peninsula of Quebec. Most of the remaining potential habitat (5%) was on northern Cape Breton Island in Nova Scotia. Potential habitat in New Hampshire, Vermont, and New York was small (1,252 km2), fragmented, and isolated (>200 km) from known lynx populations. When federally listed as threatened in the contiguous United States in 2000, inadequate regulations on federal lands were cited as the primary threat to Canada lynx. However, the majority of potential lynx habitat in the eastern United States is on private lands and continuous with potential habitat in Canada. Therefore, lynx conservation in eastern North America will need to develop partnerships across national, state, and provincial boundaries as well as with private landowners.

Journal of Wildlife Management↗

USGS2003

Recent and historical distributions of Canada lynx in Maine and the Northeast

The contiguous United States population of Canada lynx ( Lynx canadensis Kerr) is listed as threatened under the federal Endangered Species Act. However, the historic distribution of lynx in the Northeast is poorly understood. We used museum records, bibliographic records, and interviews to reconstruct the past distribution of lynx in Maine, which is at the current southern limit of the species' distribution in the eastern United States. We found a total of 118 records, representing at least 509 lynx in Maine. Lynx were observed throughout Maine, 1833–1912, with the exception of coastal areas. After 1913, lynx were most common in the forests of western and northern Maine, and absent to rare along the coast, but had not returned to southern Maine by 1999. Thirty-nine kittens representing at least 21 litters were distributed throughout northern and western Maine, 1864–1999. Populations apparently fluctuated, and in some years 200–300 lynx were harvested in Maine. Prior to the 1900s, lynx were much more widely distributed in the Northeast, ranging from Pennsylvania north into Quebec. Because Canada lynx have had a long presence in northern New England, and at times were relatively common, this species merits serious consideration in conservation planning in this region.

Northeast United States↗