Nest Predators and Rising Waters Threaten Rare Turtles (Diamondback Terrapin Turtles) – via Herp Digest

May 09, 2019

By TODD McLEISH/ecoRI News contributor

"Diamondback terrapins are the only turtle in the Rhode Island adapted for life in salt marshes, coves, and other quiet brackish waters. (Rhode Island Natural History Survey)

Diamondback terrapins are among the rarest turtles in the Northeast, and the only ones that spend most of their lives in salt marshes and other quiet brackish waters. While populations are holding their own in many locations, nest predators are an increasingly serious threat.

Three researchers speaking at last month’s Northeast Natural History Conference in Springfield, Mass., said that in almost every year the eggs in most of the terrapin nests they monitor are consumed by predators.

“Raccoons are the most important predator,” said Russell Burke, a Hofstra University biology professor who has studied diamondback terrapins at the Jamaica Bay National Wildlife Refuge in New York City for 20 years. “Everyone who works on terrapins has had the experience of watching a terrapin put a nest in the ground, and you come back the next day and find a collapsed nest hole and broken eggs.”

Danielle Marston, a volunteer terrapin monitor with the New England Coastal Wildlife Alliance, said raccoons destroy most of the nests she has observed in Buzzard’s Bay, Mass. George Bancroft, who monitors terrapins in the lower Taunton River watershed, also indicated that nest predation rates are very high.

Burke worried that the tiny survey flags he placed to mark the locations of the nests he monitored could be a roadmap for raccoons to follow to terrapin nests, so he conducted a study to learn what method the raccoons use to find the nests. He placed survey flags of various colors where there were no nests, applied a human scent to other sites, dug artificial nests, and experimented with numerous other factors.

The raccoons ignored most of the sites.

“They seemed to be cued more into a disturbance of the sand than the flags,” he said. “Wherever we dug a hole, the raccoons were interested. If you dig any kind of hole in the nesting area, the raccoons were likely to dig it up.”

Burke believes that microbes in the sand become active and release a detectable odor when the sand becomes aerated by digging a hole. But the smell dissipates within about a day or two.

“We get essentially no predation after the second day after nesting,” he said. “If the nests make it through 48 hours, they make it all the way to hatching, and that’s probably due to olfaction.”

Burke noted that there is often increased nesting activity and decreased nest predation when it rains, perhaps because the rain hides the microbe odor.

“It seems to be one of the strategies that terrapins have evolved to minimize raccoon predation,” he said.

Those who monitor diamondback terrapin nests in Rhode Island have also found high rates of nest predation, but some are succeeding in combatting it.

At Hundred Acre Cove in Barrington, where Charlotte Sornborger has been monitoring the terrapins for nearly 30 years, between 200 and 300 nests were destroyed by predators each year during the first 15 years of her studies. In addition to raccoons, Sornborger confirmed that foxes, skunks, and coyotes also predated the nests. But when she began using wire mesh “excluders,” which prohibit scavengers from digging below the surface to reach the eggs, predation rates declined significantly.

Predation at a recently discovered terrapin nesting site at the mouth of the Hunt River in Warwick was very high during the first year of monitoring in 2015 — just three of 87 nests survived to hatch — with dogs being among the chief culprits. But recent surveys have indicated that predation may not be as high as originally thought, according to University of Rhode Island professor Laura Meyerson.

Two surprising new predators, however, have been added to the list of threats to diamondback terrapins: bald eagles and osprey. Neither disturbs the terrapin nests, but the birds have been found to prey on juvenile terrapins in Buzzard’s Bay and in the Palmer River near the Barrington population. According to Sornborger, a hunter reported empty terrapin shells under an osprey platform used by bald eagles along the Palmer River, and two nearby homeowners also observed empty terrapin shells on their lawns.

Another new threat to diamondback terrapin populations is also emerging: rising sea levels.

“For Rhode Island’s terrapins, sea-level rise is really worrisome,” said Scott Buchanan, a herpetologist for the Rhode Island Department of Environmental Management. “They live right at the margins of the coastal zone, and their habitat type is going to experience dramatic alterations and impacts from sea-level rise. We don’t know what that’s going to mean for terrapins.”

“The biggest issue for us in Buzzard’s Bay,” Marston said, “is that we’re losing ground to the big surge in tidal action at our nesting locations. The nesting area is going to disappear with the projected sea-level rise. Already we’re seeing that the nests that don’t fail from predation fail from an intrusion of water into the nests. The terrapins keep trying to nest where they used to, and the nests keep getting flooded.”

With little nesting habitat available inland of their present nesting sites, the combination of predators and rising seas makes the long-term outlook for the species uncertain.

Conservation CSI: Cornell Researchers Solve Mystery of Mass Turtle Die-Off – Herp Digest

March 6, 2017, Posted on website of Cornell University, College of Veterinary Medicine (no author posted)

In April 2015, hundreds of diamondback terrapin turtles and tens of thousands of fish were found dead on a beach near Flanders Bay, Long Island. This threatened species has already experienced steep population declines around Long Island, and the unprecedented die-off had potential to impact the survival of the terrapin population in the area. Through collaboration with the New York State Department of Environmental Conservation (NYSDEC) biologists and a local wildlife rehabilitator, Cornell’s Wildlife Health Program (WHP) researchers determined that saxitoxin, a potent neurotoxin from algal blooms, was behind the die-off; their discovery was published in the April 2017 issue of the journal Toxicon.

 

Diamondback terrapins are the only turtle species that live in coastal salt marshes, and already face serious challenges. The species is listed as threatened or a “species of concern” in multiple states, and populations are declining--in Jamaica Bay, Long Island, one of the largest known populations has declined by 60% in recent years. That made the mass die-off all the more concerning for scientists. “A turtle die-off of this scale is a significant concern,” says Dr. Elizabeth Bunting, WHP director and senior extension associate with the Cornell University College of Veterinary Medicine. “The first step to preventing it from happening again is to pinpoint the cause.”

At the same time the terrapins were turning up dead, the NYSDEC closed the shellfish beds around the bay due to an algal bloom which was producing a potent neurotoxin known as saxitoxin—at levels that were the highest ever recorded in the area. Shellfish concentrate the toxin and are a human health concern if consumed, in turn creating an economic impact on commercial and recreational shellfish harvesting in temperate coastal water systems. “This algal bloom was a red flag,” says NYSDEC Biologist Kevin Hynes. “We immediately wondered if it was also the cause of the turtle deaths.”

Karen Testa, a rehabilitator at Turtle Rescue of the Hamptons, Inc., collected and submitted over 25 terrapins for examination to the WHP and the NYSDEC. The terrapins were examined by WHP staff including pathologist Dr. Rob Ossiboff and Hynes. Others were necropsied on Long Island by the Riverhead Foundation and Dr. Chris Gobler’s lab at SUNY Stonybrook. No turtles had any physical evidence of disease or trauma. The animals were also tested for ranavirus, a common cause of mortality events, but results were negative—which added to the case that saxitoxin was to blame.  However, because a saxitoxin-caused mortality in a temperate turtle species had never happened before, the scientists had to ensure the evidence was indisputable. “We had to show with a high degree of certainty that the toxin was present in the animals’ tissue, and that the animals were exposed from eating the local shellfish,” says Hynes.

The WHP and Gobler’s lab tested for saxitoxin in the terrapin tissue, while also collecting and identifying the turtle’s gut contents in order to identify the species of shellfish found in the affected turtles. The results confirmed the scientists’ suspicions—the saxitoxin was present in the turtles’ tissues, as well as the corresponding local mussel species in the stomach contents. “Although more information regarding the effect of saxitoxin on reptiles is still needed, we concluded that saxitoxin was the likely cause of the deaths of hundreds of diamondback terrapins in Flanders Bay, Long Island,” says Bunting. “The impact on this fragile and declining population from this event may threaten the survival of the species in this area.” 

Turtles Laying Eggs on JFK Airport Runway – via Herp Digest

By Josh Einiger-July 12, 2016 11:32PM

JAMAICA, Queens (WABC-TV) -- Why would a bunch of turtles leave their comfortable swampland around Jamaica Bay, and wander onto a busy runway at JFK Airport?

( http://abc7ny.com/pets/turtles-laying-eggs-on-jfk-airport-runway/1424588/ )

Video of turtles laying eggs at JFK

They've been using the runway to lay their eggs for several years, and in the process changing takeoffs and landings at the nation's fifth busiest airport.

It is peak departure time at Kennedy Airport with thousands bound for faraway places, and their planes thundering down the runway and into the air.

But at JFK this time of year, those jets aren't the only things on the move.

"I'm terrible at identifying aircraft. I know about three or four and that's it," said Laura Francoeur, PANYNJ Chief Wildlife Biologist.

It's Francoeur's job to keep the animals away from the airplanes at Port Authority airports.

"How many birds can you identify?" Eyewitness News asked.

"A lot," Francoeur said.

Tuesday she and her team were on the hunt for turtles.

Every July, dozens of diamondback terrapin turtles hike out of the salt marshes of Jamaica Bay and make their nests at the end of the runway, which juts into the Bay, basically, right in their path.

"We have a lot of sandy nesting soil, the airport was built on fill, we're right next to a salt marsh, so it's an ideal habitat for them, so it's sort of natural to them, but very unnatural from our perspective," Francoeur said.

One turtle decided to lay her eggs in the safety zone of Runway 4Left at JFK, and that is not a good thing if you're sitting on a plane.

Because for obvious safety reasons, a plane can't take off with a turtle is in its way.

And starting in 2009, out of the blue, dozens of turtles began making their homes there; prompting delays so bad, JetBlue at the time tweeted about it! "#Cantmakethisup."

"Why do they come here versus going anywhere else? That's more of the unknown that we're trying to figure out," said Melissa Zostant, a terrapin researcher.

Since then, Zostant, a Hofstra student, has helped research the terrapins' behavior.

She has been inserting microchips to track their movements, as the airport has installed with plastic drain tubing that's been successful at keeping many of them out, but not all of them.

As for the nests, Zostant builds cages around them to keep predators out. When the eggs hatch, the babies find their own way out, and into the marsh.

"I think it would be virtually impossible to get them to nest anyplace else," Francoeur said.

For now, everyone's getting where they need to go. Including the new turtle mother, released through the fence to find her way home.

Stamford's (Conneticut )SoundWaters Rescues 22 Baby Turtles Bound For Soup Pots - via Herp Digest

http://www.courant.com/news/connecticut/hc-turtles-saved-ct-20150211-story.html

Where there is a video of Leigh Shemitz, president of the SoundWaters environmental education center in Stamford, explains how the facility helped to rescue 22 baby diamondback terrapin turtles that were confiscated from international smugglers in Alaska.

By David Moran, Hartford Courant

SoundWaters, the Stamford-based environmental education center, received some unexpected guests in December just before the holidays. Twenty-two of them to be exact.

But staff at one of the leading environmental education organizations on Long Island Sound weren't about to complain.

SoundWaters' guests -- 22 baby diamondback terrapin turtles – had been seized from international smugglers in Alaska by officials from the U.S. Fish and Wildlife Service and U.S. Customs and Border Protection Service. The environmental group's brood were part of 211 baby turtles that were found stuffed into boots at the Anchorage airport in December of 2014.

The turtles were likely bound for China, where turtle soup is considered a delicacy and the market for turtles is lucrative, according to SoundWaters President Leigh Shemitz.

When Shemitz said SoundWaters learned that officials were looking for foster homes for the turtles, she said the facility "jumped at the opportunity."

"The call went out to people who are involved in turtle research and education to find home for these turtles," Shemitz said. "We're part of a nationwide group, they reached out, and we said we'll take as many as you need."

Shemitz said the turtles, which are about 4 to 6 months old and 1 to 2 inches in size, are "now thriving" at SoundWaters and plans are in place to introduce the turtles to the public in the spring. In the meantime, many of the turtles got to take their first plunge into deep water on Wednesday.

"Today's the first time they actually got into our terrapin exhibit and went from maybe a two-foot long small tank to actually being in a large tank where they can dive and climb and they really seem to like it," she said.

Wandering Turtles Clog Runways at Kennedy Airport - via Herp Digest

JFK, situated in the middle of Jamaica Bay, has been a favorite habitat for diamondback terrapin turtles

By Marc Santia, NBC News, 6/20/14  

Wildlife biologists working to keep turtles from wandering onto the runways of Kennedy Airport are beginning to see their efforts pay off.

JFK Airport, situated in the middle of Jamaica Bay, has been a favorite habitat for diamondback terrapin turtles, which only leave the brackish waters and step on shore to lay eggs.

But airplane and turtles sharing the same runway could pose a threat. 

"Anything can be a hazard to aircraft, so we monitor all kinds of wildlife population here," said Laura Francoeur, one of Port Authority's wildlife biologists helping to keep the balance between passenger safety and nature preservation. 

"Keeping terrapins off also saves the terrapins so they don't get run over potentially, and it also helps eliminate any operational impacts delaying flights at the airport," said Francoeur. 

June is the main nesting season for turtles, making it the busiest time of the year for biologists working on the terrapin tracking project. 

Two years ago at this time, more than 800 turtles were captured and released into the wild. Last year, the number was 400. 

This year, there have only been 80 turtles stopped near the runways of JFK, thanks to new efforts like a black corrugated plastic fence acting as a turtle barrier. 

Francoeur says the fence allows the terrapins to actually nest outside the barrier so there's still a habitat available for them to nest in. 

But every once in a while, a bold turtle comes out of its shell and makes it past the fence. Port Authority biologists are constantly patrolling the airport and will scoop up the reptile before they reach the runway. The turtles are then tagged, released and tracked.