by David Gaillard
Sixteen chapters of a scientific assessment of lynx in North America are now available on the Internet. The report, released by the U.S. Forest Service, was co-authored by 18 American and Canadian lynx ecologists, and addresses all aspects of lynx biology, conservation and management.
In anticipation of the report, the U.S. Fish and Wildlife Service (FWS) delayed its decision about whether to protect the lynx under the Endangered Species Act, extending its deadline to January 8, 2000. Ironically, the report seems to add little new information to what is already in FWS’ administrative record on lynx. If anything, the report provides additional evidence that protective measures should be implemented without further delay!
Here are excerpts from the report that highlight the major issues jeopardizing lynx survival in the northern forests of the lower 48:
• Lynx in the Contiguous U.S. are Imperiled...
We know remarkably little about the current status and numbers of lynx in the contiguous United States. However, what little we know indicates that the subpopulations are not large. Until we better determine the current location and sizes of lynx subpopulations, it is unwise to assume that these populations can be reduced or further isolated without sharply increasing the risk of their individual and collective extinction. (McKelvey et al., Chap 2, p.14)
• ... Especially Lynx in Areas Isolated from Canada
Arguably, the lynx in the northeastern United States are effectively isolated from the main Canadian populations by the St.Lawrence Seaway and from the Great Lake States by agricultural conversion and urban development. Similarly, boreal forests in Colorado and Utah are separated from the larger areas of
boreal forest in Wyoming by at least 100 km. If these areas have become effectively isolated, then they represent special areas of concern and, if they still contain native populations, these populations are particularly endangered. (McKelvey et al., Chap 2, p.13)
• Habitat Loss and Fragmentation
Fragmentation of habitats occupied by lynx (including increased openings, higher road densities, exurban residential development, and wider use of snowmobiles and devices that compact snow in areas with deep, soft snow) is a plausible mechanism for the questionable conservation status of the lynx in the contiguous United States. (Buskirk et al., Chap 4, p.13)
• Forest Practices
We caution against uncritical application of ecological understandings derived from the North to southern lynx and we emphasize the potential importance of late-successional forests as habitat for hares, red squirrels, and lynx in the southern part of the range of the lynx. (Buskirk et al., Chap. 14, p.1)
• Roads
Roads into areas occupied by lynx may pose a threat to lynx from incidental harvest or poaching, increased access during winter for competing carnivores, especially coyotes, disturbance or mortality from vehicles, and loss of habitat. (Aubry et al., Chap. 13, p.19)
• Mortality Due to Trapping and Shooting
Although legal harvest is no longer a conservation concern, human-caused mortality is believed to be additive in the low-density lynx populations characteristic of southern boreal forests. If so, illegal or incidental harvest could significantly reduce population numbers of lynx in southern regions. (Aubry et al., Chap. 13, p.19)
• Reliance on Canada’s Lynx
We cannot assume that lynx populations in the contiguous United States will be maintained by dispersal of lynx from Canada, nor that connectivity with larger habitat areas in Canada will be maintained in perpetuity. (McKelvey et al., Chap. 15, p.9)
• The Upshot
Our analysis of the current and historic distribution of lynx populations in the United States indicates that large, contiguous areas of suitable habitat are necessary for population persistence. (McKelvey et al., Chap. 15, p.8)
Our challenge, from the perspective of maintaining lynx and their prey in the context of ecosystem management, is to design management strategies that result in dynamic, sustainable landscapes that approximate the composition of natural systems. (McKelvey et al., Chap. 15, p.10)
