Tuesday, May 31, 2011

The 2011 Barnegat Bay Nesting Season


On May 31, there were multiple reports of terrapins nesting at Barnegat Bay, New Jersey. Four marked adult female terrapins were captured on North Sedge Island and three of them dug nests. At Long Beach Island, two female terrapins nested. At LBI, we were not able to identify the nesting. The first days of June, we had ten female terrapins captured and six identified nests. On June 4, Nicole M. moved a nest from Cedar Bonnet Island to the LBIF hatchery and marked a female at LBIF! This week, June 5, Jane and Marc volunteered much time at Barnegat Light. They found a nest with a clutch size of 20 eggs!
At Sedge on June 10, it was the annual "terrapin arribada" with 23 females coming ashore. Five nests were moved and 17 females came up after 12 noon! It was a busy day. The previous night, it seems that the mink returned to the Island and destroyed all reference nests outside of the hatchery. Five known nests were predated. After Jules used her night vision camera, it was determined that a raccoon has inhabited the Island and is wreaking havoc on terrapin nests, and other wildlife on the Sedge. We will be humanely trapping the raccoon the week of June 20.
There has been no success trappin the raccoon this part week; however, nesting picked up on Sedge with 12 terrapins making landfall on June 23 and June 24. There are a total of 33 nests on the Island this year so far. On June 25, we had two terrapin nests on Sedge Island with 20 eggs each! This is new record. Terrapin AHPW produced 20 eggs on June 24. Terrapin AJKQW produced 20 eggs on June 25!
On July 3, the nesting season is coming to a close but we will still see some terrapins coming up from time to time for the next two weeks. Thanks to our fantasic volunteers.

On July 8, AHPW came back to dig her third nest of the season. She deposited 16 eggs! Way to go AHPW - one of originally marked terrapins from 2002! Next up will be our hatchling recovery program! On July 21, we assessed an early nest that has eggs that are incubating well. Our first nest produced emerged hatchlings at Sedge on August 10, 2011 with nests 1 and 2 producing hatchlings on consecutive days. We had two more nests with full incubation and emergence at Sedge. On August 20, nests 12 and 23 produced a total of 29 hatchlings out of a 29 eggs. On August 24, we completed a hatchery assessment with all nests in the 10's and 20's. Overall, we recovered over 70 hatchlings. Sadly, on August 31, we assessed the hatchery on N. Sedge Island and Hurricane Irene claimed the remaining nests. Washover from the storm knocked over the protection cages. It seems that some of the hatchlings were able to emerge; however, it seems that some predators were able to access the hatchery when the water was high (i.e., mink).

Wednesday, May 25, 2011

Horseshoe Crab Poaching

Although most of our research is focused on diamondback terrapins, we try to never lose sight of the fact that by helping the terrapins hopefully we are also conserving the other organisms in the bay. Horseshoe crabs just so happen to be one of my favorite creatures in Barnegat Bay (other than terrapins, of course!). We commonly catch horseshoe crabs in our fyke nets when we're trapping terrapins. We've also found horseshoe crab hatchlings on Conklin Beach which is one of our terrapin nesting sites. These crabs are commonly referred to as living fossils because they have changed very little in the past 250 million years. Horseshoe crab populations are dwindling due to the high numbers of crabs that are harvested for bait and fertilization. Luckily, in 2008, the state of New Jersey banned the harvest of horseshoe crabs. Unfortunately, some people still try to harvest horseshoe crabs even though there are regulations forbidding this practice. Three individuals were just caught in Ocean City, NJ on Monday poaching horseshoe crabs. Thank goodness someone called the police!

Thursday, May 5, 2011

Ouch! Even more terp injuries ...

Over the past five summers (2006 to 2010), we've captured over 2,000 terrapins in the Edwin B. Forsythe National Wildlife Refuge. Of those turtles, 17.4% have scars or open wounds from past or present injuries. Many of these injuries were caused by predators or by anthropogenic sources such as automobiles or boat propellers. I've always been interested in boat injuries considering that most of my research is based on the effects of recreational boat sounds on terrapin behavior. Of the injured terrapins we've captured in Forsythe, 18.9% of those injuries were attributed to boat propellers. It's pretty easy to tell if an injury was caused by boat strike because there is a slash mark in the terrapin's shell from the propeller. Typically, these injuries cause major damage in both the carapace (top shell) and plastron (bottom shell).

I apologize for the graphic photos, but this is yet another example of why the terrapins in Barnegat Bay need your help. Sign up for an expedition to help save the terps this summer!