Project Results

Last summer, we used Experiment to fund our current research project on diversity and habitat use of eastern hognose snakes. Our research examines how and why these snakes on a barrier island are different from those that live on the mainland. Typically, hognose snakes measure about 3 – 4 ft. long, but all of the snakes we have found on nearby barrier islands have been under 2 ft. — a phenomenon known as insular dwarfism.

Really cool things happen on islands, and even today we don’t know what’s going on. It seems every animal has a different way of adapting to an island. We have a pretty good idea that hognose snakes that live on barrier islands are smaller, but we don’t really know why. No one does, so we’re going to try to figure it out. The first step in answering this question is gathering enough data to confirm that there is a significant size difference.

About This Project

Ask the Scientists

What is the context of this research?

Snakes are in a predicament: not only are they maligned by the general public, often cited as among the most feared and loathsome animals (Burghardt et al. 2009), but they also suffer from a lack of attention to population declines compared to other organisms (Meylan and Ehrenfeld 2000, Miller 2000, Norris 2007). In addition, snakes as a group are understudied, and we know little about the biology or ecology of most species (Dorcas and Wilson 2009), preventing the development of effective conservation measures. The Eastern Hognose Snake (Heterodon platirhinos), a species native to NY, and the subject of my research proposal, is a prime example of this predicament: the subject of loathing and apathy, confounded by sizable knowledge gaps.

Like many other snake species, the Eastern Hognose Snake is poorly studied across its range, but the few studies that have been conducted were focused on mainland populations; their ecology on barrier beaches has NEVER been formally studied, and therefore it is UNKNOWN how barrier beach populations of hognose snakes behave, utilize habitat, or how they survive on the few prey species available there. This information will be CRUCIAL to understanding how hognose snakes interact with their environment, which can aid CONSERVATION decisions and influence management actions on barrier beaches from Massachusetts to Florida.

Major research questions:

What habitats are hognose snakes using?

How far do hognose snakes travel?

Where do hognose snakes hibernate?

How close are they coming to the beach/ where people hang out?

What is the significance of this project?

Eastern Hognose Snakes are one of the most INNOCUOUS and CHARISMATIC snake species in North America, possessing an upturned rostral scale and exhibiting an extravagant death-feinting display when provoked (see video). However, despite their mild nature, hognose snakes have been subject to heavy persecution throughout their range, where locals often (erroneously) consider these snakes to be deadly, earning colloquial names such as “spreading viper” or “hissing adder.” Some people think these snakes spit venom, sting with their tail like a scorpion, or even possess a paralyzing glare! It is no surprise that human persecution is a large contributor to the decline of this species (Ernst and Ernst 2003).

Eastern Hognose Snakes are now considered a SPECIES OF REGIONAL CONCERN by both the Northeast Endangered Species and Wildlife Diversity Technical Committee (Therres et al. 1999) and Northeast Partners in Reptile and Amphibian Conservation (NEPARC 2010). In New York, hognose snakes are designated as “VULNERABLE” (Natureserve 2013), but do not currently receive habitat protection, although the New York State Department of Environmental Conservation (DEC) does list hognose snakes as a SPECIES OF SPECIAL CONCERN, a species in which "a welfare concern or risk of endangerment has been documented in New York State” (DEC 2007).

The health of the Eastern Hognose Snake population in Southern New York is poorly known. Despite once being widespread and so common that they could be literally collected by the barrel (Engelhardt 1915), the hognose snake was considered extinct on Long Island in 1996, until 2001 when a population was re-discovered at Brookhaven National Laboratory (Finn 2005). Subsequent isolated populations have been re-discovered across Long Island, but the DEC considers the hognose snake population on Long Island to be DECREASING (NYS DEC 2006).

What are the goals of the project?

For this study, I will radio-track Eastern Hognose Snakes and follow their movement patterns. Radio-tracking involves surgically implanting a small radio transmitter inside the abdomen of the snake, and subsequent re-finding the snake using a hand-held antenna and receiver. This procedure allows the researcher to gain insight into habitat utilization on a regular basis, and removes survey bias by allowing the animal to be found even when it would otherwise be hidden from view (in dense vegetation, underground, etc.). Don't worry, the snakes receive anesthesia and pain killers just like a person would during and after surgery.

The funding I am requesting is sufficient for FIVE radio transmitters made to order especially for this task and can only be purchased directly from the manufacturer. The company I ordered from, Holohil, is often considered an industry standard for radio-tracking snakes. My university already has an antenna and receiver, so I will not need to purchase these.

I have extensive experience radio tracking snakes and other animals, including rattlesnakes and black bears, and last year I carried out a similar project studying hognose snakes in upstate New York. Tracking animals requires practice and skill, so my past experiences will ensure successful completion of this project.

STEPS:

1) Survey study site and locate hognose snakes

2) Capture snakes and take them to The Bronx Zoo for surgical implantation of the radio-transmitters

3) Keep snakes in captivity until they recover from surgery

4) Release snakes at point of capture

5) Re-locate snakes on a regular basis

6) Use GPS data to model habitat use

7) Design management recommendations to advise land managers on the best ways to conserve hognose snakes