Conserve Wildlife Blog

Posts Tagged ‘reptile’

Photo from the Field: Timber Rattlesnake Emergence

Monday, May 18th, 2015
Warming weather brings out one of New Jersey’s most misunderstood species

By: Michael Davenport, GIS Program Manager

I recently had the opportunity to accompany Kris Schantz, a biologist with the NJ Endangered and Nongame Species Program, to search for timber rattlesnakes (and northern copperheads) emerging from their dens in northern New Jersey.

Many New Jersey residents are surprised to learn that we have venomous snakes within our state, the most densely populated state in the U.S. We have two venomous species, in fact.

A timber rattlesnake resting outside its den. © Mike Davenport

A timber rattlesnake resting outside its den. © Mike Davenport

The timber rattlesnake is an Endangered species in New Jersey, while the northern copperhead has a status of Special Concern. To learn more about venomous snakes in New Jersey, please read my blog entry from May 13, 2011 and visit our online field guide:

 

Volunteers needed to help protect terrapins!

Friday, April 24th, 2015
Training Session scheduled for May 12th at 6pm in Tuckerton
A female terrapin pauses while crossing Great Bay Blvd in Little Egg Harbor, NJ.

A female terrapin pauses while crossing Great Bay Blvd in Little Egg Harbor, NJ.

We work hard to protect wildlife for future generations to enjoy. One of those species, who is largely an underserved species in New Jersey is the northern diamondback terrapin. Terrapins are so cool yet hardly noticed by many. They face a HUGE amount of threats. To list a few (from greatest to least): Poaching, drowning in crab traps, road mortality, predation (usually of eggs or young), and collisions with boats and boat props. That’s a long list of threats to the health of their population, which no one really knows how they are doing…

What we’ve done with them in Tuckerton and Little Egg Harbor is address a problem which was believed to be the root cause for their decline in the area. Studies that have been done in the area have stated that the overall size and age of terrapins has decreased over time. Another documented the total road mortality rate at 70% of individuals that crossed the road (the actual rate in a more recent study was around 30%, but that’s still high and having an impact). Either way, each year many terrapins are being injured and killed by motor vehicles.

Each year we recruit volunteer “Terrapin Stewards” to help patrol area roads. This hardy and extremely dedicated group of volunteers work tirelessly to prevent terrapins from becoming road kill and also collect valuable data on their annual migration to find suitable nesting areas. On May 12th at 6:00pm we are hosting a short training session for anyone interested in volunteering this year. Attendees will also learn more about all of the work that we’ve done over the past 5 years.

Terrapin nesting season begins

Wednesday, June 6th, 2012
Be Terrapin Aware this summer!

by Ben Wurst, Habitat Program Manager

Last Thursday there was a flurry of activity throughout coastal New Jersey. It was one of the peak days of the beginning of the northern diamondback terrapin nesting season. I had scheduled myself to be off to work on projects around my house but ended up working for half the day on our Great Bay Terrapin Conservation Project. Female terrapins were everywhere! They were crossing all over Great Bay Blvd., a 5 mile long road that bisects pristine terrapin habitat. The shoulders of the road are suitable nesting habitat as well, so at times as many as 10-15 terrapins could be seen in one small section of the road. There were so many that one terrapin bumped right into another one on the shoulder of the road!! They were digging nests and laying eggs all over the place. It was certainly a rare sight. Luckily traffic was mild and  the weather was clear so there were little road kills. One female fell victim to a Little Egg Harbor Twp. mower who was mowing the edges of the road. This certainly wasn’t the best day to mow the shoulders! Before more terrapins could be killed we contacted LEHT public works and they called off their mower until further notice. On a side note, we have asked the township and the environmental commission to adopt a delayed mowed regime in the past and unfortunately one terrapin died because of this. I even emailed the public works director early last week about nesting activity picking up and I asked for him to please let me know when they were planning to mow so we could have someone walk in front of the mower to be sure no terrapins were hit. On the positive side, we were able to salvage 7 eggs from the terrapin, and they were successfully placed in a hatchery in Loveladies on LBI. We have our fingers crossed that they’ll hatch later this summer!

Finally, we have had more of a presence on Great Bay Blvd this year with the assistance of our new intern, Kristin Ryerson. She is collecting data (size, age, weight, and other data) on terrapins that she encounters while conducting road patrols on Great Bay Blvd. We’ll be using this data to compare it to some collected in Barnegat Bay and past studies that were conducted on the road. Her position is a volunteer position so I really appreciate all of her help so far! We also have volunteers who are acting as “Terrapin Stewards” where they also conduct road patrols to collect sightings of terrapins, educate visitors to the road about terrapins, and they also make sure terrapins safely cross the road. Without their help this project would not be successful!

Reduce the speed limit on Great Bay Blvd.

Wednesday, January 18th, 2012
Ask Little Egg Harbor to help us protect terrapins!

by Ben Wurst, Habitat Program Manager

This female northern diamondback terrapin was not able to lay her clutch of eggs after being killed by a motor vehicle on Great Bay Blvd. © Ben Wurst

Currently there are no posted speed limits on Great Bay Boulevard from Sea Isle Drive to the east end in Little Egg Harbor Township, Ocean County, New Jersey. The road bisects one of the largest state wildlife management areas along the entire coast of New Jersey which is also designated as the Jacques Cousteau National Estuarine Research Reserve. Designation as a National Estuarine Research Reserve is “to promote the responsible use and management of the nation’s estuaries through a program combining scientific research, education, and stewardship.” The habitat alongside the road is home a diverse array of wildlife and one species, the northern diamondback terrapin, often crosses the roadway to get to prime nesting areas along the road shoulders.

Female terrapins range in length from 6-9″ and actively search for nesting areas during summers months from May through July. They are hard to see with their dark coloration and high speed limits make identification even harder. On some days as many as 50 terrapins can be seen crossing the road. Many people stop to help these terrapins cross safely and they themselves put their lives in jeopardy. Luckily no one has been seriously injured or killed yet. Unfortunately, terrapins aren’t so lucky, previous studies have indicated that up to 30% of terrapins are killed on Great Bay Blvd. while attempting to find suitable nesting areas (Szerlag and McRobert, 2006).

The Township of Little Egg Harbor knows about the problem there but has done little to help solve it. Public safety should be a serious concern for any type of government. In other parts of New Jersey and in other states people and property have been seriously injured or killed and damaged while either helping one cross safely or by avoiding a collision with them.

Little Egg Harbor can help reduce the chances that a pedestrian gets killed or injured, and they can reduce the amount of terrapins that are killed by motor vehicles. By reducing the speed limit along the road from 50 mph to 30mph both people and wildlife benefit and motorists get to their destination safely.

References: 
Szerlag, S., and S. P. McRobert. 2006. Road occurrence and mortality of the northern diamondback terrapin. Applied Herpetology 3:27-37.

 

Mapping Rattlesnake Dens in Northern New Jersey

Friday, May 13th, 2011
PROTECTING WILDLIFE BY MAPPING THEIR HABITAT

By Michael J. Davenport, Marine Species & GIS Programs Manager

A juvenile timber rattlesnake at a den site. © Mike Davenport

Having accurately mapped rare species data is essential for insuring that critical habitat for those species remains protected.  For that reason, I recently accompanied Kris Schantz, a biologist from the NJ Endangered and Nongame Species Program, in documenting two timber rattlesnake den locations in northern New Jersey using a GPS (global positioning system) unit.  Our goals were to see if the rattlesnakes had emerged from hibernation, survey how many were present, and to accurately map their locations in the heavily wooded area less than 30 miles outside New York City.

Using a GPS unit to map a rattlesnake den. © Mike Davenport

Timber rattlesnakes (Crotalus horridus horridus), like other reptiles, are cold-blooded.  In order to survive through the long, cold winter in New Jersey, they hibernate in dens.  Research has shown that rattlesnake dens in the northern part of the state can vary from rocky outcroppings with crevices, ledges or boulders to forest interior dens consisting of a few rocks and a hole in the ground.  In New Jersey’s Pinelands, however, rattlesnake dens are quite different.  Rattlesnake dens in the Pinelands are usually underground crevices near bodies of water, often underneath large tree roots.

Rattlesnakes will almost always use the same den year after year.  In addition, rattlesnake young typically follow the scent trail of their mother in order to find their way to her den their first fall, or may follow any timber rattlesnake to a suitable den.  As a result, a good den site may provide a winter refuge for a number of rattlesnakes of all age classes, as well as other species of snakes.

Since the goal of our mission was to map den locations, we had to make sure we arrived at the den site once it was warm enough for the rattlesnakes to come out of their crevasses to bask but before they had enough warm weather to travel away from the den site.  Timing was crucial.  After a week with some fairly warm days mixed with very cool nights and a few cool days, we ventured out during the last week of April on a day when the air temperature climbed into the lower 80’s.

The first den site we visited required a fairly long hike through a rocky, deciduous forest.  Fortunately, Kris had visited both den sites several years earlier so she had a good idea of where we needed to go.  We were fortunate to find two individuals at the den site, one yellow-phase juvenile and one yellow-phase sub-adult or young adult.  While I GPSed the den site, Kris attempted to determine their sex based on their appearance (the young adult was a female but the juvenile’s sex could not be determined).

GPS units work when there is an unobstructed line of sight to four or more GPS satellites.  With 7-8 satellites being detected by the GPS unit, my task of mapping the site was fairly easy and took little time.  The trees had yet to leaf-out so my GPS unit had a clear signal from above.  We also observed a northern black racer (Coluber constrictor constrictor) at the den site.

The second den site required a much longer and more strenuous hike accompanied by swarms of black flies.  At that location, we observed three rattlesnakes – one black-phase adult (sex undetermined), one yellow-phase adult male, and one yellow-phase sub-adult or young adult (sex undetermined).  GPSing this location took a little more effort though due to the terrain both because it was more difficult to get to the site and once there, the terrain made getting a clear signal on the GPS unit a little more tricky and it took far longer than at the first den.

Out of the five rattlesnakes we observed, only one ever rattled.  Rattlesnakes rely on their camouflage as their first line of defense.  Even when we were close by, they remained motionless.  At no point did any of the snakes approach us or attempt to strike.  The only two individuals which moved at all during our survey, moved away from us into rock crevasses and that was likely due to our prolonged presence staring at them.

Snakes, and venomous snakes in particular, have an undeserved bad reputation.  At no point during our survey did I ever have any fear of being bitten by a rattlesnake.  In all honesty, I was actually far more afraid of being bitten by a tick instead (I only found about four or five on me during the entire day).

For more information on timber rattlesnakes, visit Conserve Wildlife Foundation’s on-line field guide to New Jersey’s rare species at:  http://www.conservewildlifenj.org/species/fieldguide/view/Crotalus%20horridus%20horridus/