By Michele S. Byers
The beautifully colored corn snake is endangered in New Jersey. It is a southern species, living at the northern limit of its range in the sandy pine forests of New Jersey’s Outer Coastal Plain, deep in the Pine Barrens.
This gorgeous snake, also called the red rat snake, established a population in the Pine Barrens after the last ice age. As glacial ice retreated and the climate began warming about 12,000 years ago, the sea level was much lower than today. Delaware Bay and the sand beneath today’s Atlantic Ocean were dry land, exposed for miles offshore.
Slowly but surely, southern plants and animals migrated north and east along these exposed sandy lands, which became coastal forests. Many Pine Barrens species arrived along a forested corridor that now lies well beneath the sea.
As the sea rose, many species that cannot fly, tolerate salt water or blow in the wind became isolated in New Jersey’s ark of biodiversity, the Pine Barrens. The endangered corn snake is one such creature and its New Jersey population is completely cut off from southern populations.
Corn snakes in New Jersey face many natural threats, including eastern kingsnakes, black racers, birds of prey, alien species like red foxes, recently arrived species like coyotes, and native mammals from gray foxes to raccoons to skunks to shrews.
But corn snakes face two far more insidious threats, ones they did not learn about and adapt to avoid: road traffic and poachers.
Many Pine Barrens corn snake populations are located near busy roads, and adults – including females with eggs – are often run over. Corn snakes are highly prized by the pet trade, and although they are bred in captivity, many collectors want unique wild specimens from habitats like the Pine Barrens. Illegal poaching is common.
With permission from the New Jersey Endangered and Non-Game Species Program, two corn snake experts – Robert Zappalorti of Herpetological Associates and Howard Reinert from The College of New Jersey – have begun a “head start” program to boost the survival odds of newly hatched corn snakes.
Bob, Howard and other volunteers radio track egg-laying females and scour forests for freshly laid eggs in nests in the sand. In some nest areas, they install predator-exclusion devices that female corn snakes use, laying large batches of eggs safely inside devices that predators cannot penetrate.
Volunteers monitor nests and eggs, and when young snakes hatch they are tagged with tiny, permanent identifiers just below the skin.
The first year of a corn snake’s life is the most treacherous. They are small and vulnerable, and their first winter hibernation is a real gauntlet for survival.
In the “head start” program, half of the monitored newborn snakes are taken to the lab, where they do not have to endure long hibernation without food in near freezing temperatures. Volunteers feed the young corn snakes and by the time April showers roll around, the 1-year-old babies look more like 2-year old snakes.
The “head start” corn snakes are released to their original nest site, where their smaller brothers and sisters have spent five to six months in cold hibernation just below the frost line, deep inside a rotted tree root or abandoned mammal den.
Which group will fare best in the long run? Only time will tell.
The “head start” program is now in its second year. By next spring, 40 head-started corn snakes will roam the woods. They probably will not be seen again until they are adults, ready to breed.
Hopefully, a few will reach adulthood in about four years, and some of the surviving females will return to nest in the same nursery areas where they hatched. If a significantly higher percentage of tagged, head-started individuals return, in comparison to tagged snakes that faced their first winter without human assistance, we will know the “head start” program worked.
You might wonder, “Why not let nature sort out which young snakes survive?”
Unfortunately, the fate of New Jersey’s corn snakes, like many species, is no longer determined by “survival of the fittest.” Road traffic and poachers are wiping out nature’s fittest adults … the very snakes that should be breeding for many years. Hopefully the “head start” program will help save this incredibly beautiful animal.
Hats off to intrepid conservationists like Robert Zappalorti and Howard Reinert, who devote their volunteer time and resources to innovative research on protecting endangered creatures on our public lands.
For more information about preserving New Jersey’s land and natural resources, visit the New Jersey Conservation Foundation website at www.njconservation.org or contact me at info@njconservation.org
Michele S. Byers is the executive director of the New Jersey Conservation Foundation, Far Hills.
