POUGHKEEPSIE JOURNAL (New York) 25 April 04 Habits put rattlers at risk - Group hibernation, migration make snakes easy to capture, kill (Paul Perri)
For Hudson Valley residents, the warmer temperatures and longer days that mark the progression of spring are an exciting time.
With warmer weather comes the chance to observe the emergence of the reptiles and amphibians, whose yearly activity depend on temperature. The spring peeper is usually the first voice signifying the start of the new season, followed by the wood frog and the distinct trilling of the American toad. Turtles begin to appear basking on logs and an occasional garter snake can be seen on the warm southern exposures around buildings and stone walls.
As the valley greenery creeps up the hillsides, one of the largest and most visually striking members of the reptile community starts to appear from its winter hibernation -- the timber rattlesnake.
For many people, it may be a surprise that a venomous reptile lives in parts of the Hudson Valley. Unfortunately, most people will never have the rare and unforgettable experience of witnessing a timber rattlesnake in the wild.
Timber rattlesnakes face increased pressures of local extirpation even in some of the most remote and protected areas where they remain.
Reduced to about 25 percent of their original population and eliminated in areas where human contact is likely, the species was listed as threatened in New York state in 1983. Even with this protection, threats to rattlers have not been reduced.
Changing human interests, demographics and technologies have created new dangers for this species. Even in largely protected areas, such as the Catskill Park, where I have been studying them for the past few years, threats to their survival are increasing.
Historically, organized rattlesnake hunts, a bounty system, resource extraction such as logging and bluestone mining and the belief that ''the only good snake is a dead snake'' were the reasons for drastic population declines.
Presently there are other factors contributing to their disappearance. The collecting of many snakes from remote areas for exotic food markets and the pet trade is now a considerable threat. This reason alone has caused a sharp decline in the species over the past 20 years and is considered the most direct threat affecting their survival. One illegal collector from New Jersey bragged of having caught more than 10,000 timber rattlesnakes.
Massive removals like this are possible mainly because of this snake's behavior.
In northern climates, the life of the timber rattlesnake is focused around communal hibernation dens. Every year, the snakes return to the same den to hibernate. They are especially vulnerable when congregating for hibernation at the winter dens and when emerging in the early spring. Rattlesnake hunters and collectors can severely deplete a colony of rattlesnakes during these times.
If the snakes manage to evade poachers during their spring emergence and start migrating to a summer range, their dangers are not over.
The next set of perils, especially in the Catskills, has been the development of upscale private residences close to timber rattlesnake dens. The few remaining areas suitable for dens are attractive to humans for some of the same reasons -- peaceful seclusion, southern exposures, and the bonus of beautiful valley views.
High-end developers can now put their clients, usually unaware, at sites rattlesnakes have remained in for thousands of years.
Development in these areas makes more snakes die from automobile traffic or homeowners who worry about their children and pets.
Timber rattlesnakes are susceptible to human depredation in part because they don't reproduce often. In northern New York, the average age of first reproduction for a female is nine years; she will reproduce again at roughly four-year intervals. When the snakes reproduce, they have an average of 10 offspring. For various reasons, few of the snakes live longer than five years. Of the few that make it to adulthood, most die because of humans.
They are also threatened because they range far and wide. Males travel on average 2.5 miles from their den site and have been known to go as far as 4.5 miles. Females range 1.3 miles on average and have been known to go as far as 2.3 miles.
This migration requires about 41,000 acres of habitat. Even for dens in the Catskill Park that have as much as 57 percent of this habitat protected, timber rattlesnake populations are declining rapidly. If they manage to escape poaching and the chance observation by a homeowner with a shovel, roads bisecting their habitat account for many dead snakes.
Timber rattlesnakes pose very little threat to humans. They are not aggressive and will usually retreat quickly if confronted by a human. When a rattlesnake cannot retreat, it will rattle as a warning.
Snakebite by any venomous species in New York and New England is very rare. Of all bitten by snakes, more than 99 percent recover.
In the past five years in the Catskill region only two venomous snakebites have been recorded, one from a copperhead and one from a timber rattlesnake. The rattlesnake bite occurred on the victim's finger while he was allegedly riding a bike.
National snakebite statistics reveal the typical victim is male, under the age of 30 with an elevated blood alcohol concentration.
Even with legal protection, this creature's population and habitat is rapidly disappearing.
Having the opportunity in the past few years to point out a timber rattlesnake quietly coiled on the forest floor to individuals who would not normally go out of their way to see a snake, I can verify the adage that ''nobody who sees one ever forgets.''
Their most common prey is the white-footed mouse, an efficient transmitter of Lyme disease.
Where this snake remains, its presence symbolizes an area of significant wilderness.
Without considerable change, the timber rattlesnake in New York has little chance of survival. Fortunately, educating the public about this snake, and dispelling irrational fears about snakes, could go a long way in protecting them.
Rattlesnake risks
- Hunters and collectors are able to capture large numbers of timber rattlesnakes when the snakes return to their communal hibernation dens for the winter or when they leave the dens in the spring.
- The snakes are also at risk when their tendency to mi-grate over a wide range puts them in the path of humans.
- Infrequent reproduction makes it hard for the rattlesnake population to recover.
Paul Perri studies timber rattle snakes in the Catskill Mountains. He lives in Saugerties.
Group hibernation, migration make snakes easy to capture, kill