Animal management efforts in question

Why did the deer cross the road? It didn't. Neither did the bear, fox or coyote, according to a new study, co-authored by New York State Museum researchers, which finds that underpasses designed to keep wildlife off of the Adirondack Northway are not working.

The study, published in the spring/summer issue of the "Adirondack Journal of Environmental Studies," says that out of the 19 passageways under I-87 that were surveyed, only four raccoons passed through a single culvert. The researchers suspect the raccoons were not even using the culvert as a passageway but, rather, were hunting for crayfish or amphibians in the wet tube.

The authors, who also included researchers from the New York City-based Wildlife Conservation Society (WCS), set up camera traps and used tracking techniques to record animals using both drainage culverts and underpasses specifically designed for wildlife and human use. The study was done in 2002 during the spring when many animals are active in preparation for breeding.

The results highlight the potential impact that proposed new interstate development in the area would have on wildlife. "Many animals do not cross the road and this isolates populations on either side," said Scott LaPoint, a former State Museum biologist, who was the lead author of the study. When wildlife become isolated, there is increased inbreeding. If they disappear on one side of the highway, they can't recolonize on the other and there is a greater danger of local extinction. Based on the cost and success of mitigation efforts elsewhere, the study also suggests that there would be no "easy fix" available to help wildlife cross the road.

The passage rates along the Northway were much lower than those in Florida, where wildlife underpasses have been used with moderate success. The reasons why Adirondack wildlife avoid underpasses are unclear, although researchers suspect that popularity of certain underpasses among ATV-users may be partially to blame. Some studies have found that most mammals prefer large underpasses to small ones and this study indicates off-road vehicle users feel the same way.

"We recorded 20 passes by ATVs through the larger passageways and none of these was used by wildlife," said Roland Kays, a co-author of the study and mammal curator at the State Museum.

Another possible reason could be that wildlife simply do not like the underpasses. "A highway engineer's view of a nice underpass may be quite different from that of a white-tailed deer," said WCS researcher Dr. Justina Ray, another co-author of the study.

The authors say that the results of this study indicate that new interstates planned for the region, including the proposed "Rooftop Highway" to connect I-81 and I-87 from Watertown to Plattsburgh, would take a heavy toll on wildlife.

"Any cost-benefit analysis regarding the proposed 'Rooftop Highway' must consider not only immediate costs to wildlife in terms of road-kills and population isolation, but also the added budgetary considerations needed to attempt to mitigate these costs," said LaPoint.