On the marshy, shallow edge of the York River, Randy Chambers and his students from the College of William and Mary lined up the dead turtles they found drowned in a commercial crabbing trap.
Chambers, a wetlands ecologist, and his students selected for directive summer research laid the turtles on the grass, shell to shell. They counted 30 dead, all diamondback terrapins, the only turtles native to the brackish saltwater marshes.
The group found the turtles the first time they visited the Catlett Islands to begin their summer research. The topic: A population study of the terrapins.
The shallow edge of the river is not a common crab fishing spot, Chambers said, but finding dead turtles there is.
While 30 dead turtles — each about 5 to 7 inches long — in one trap may sound like a lot, but the known world record is 94 caught in a 2x2-foot wire trap. The trap, which was found in a Georgia creek, almost wiped out the entire local population.
Among the turtles found in the trap at Catlett Islands was one crab; it was alive.
Traps often get swept down river and catch turtles, which can’t breathe underwater and drown.
But careless commercial crabbers aren’t to blame, said Dan Knott, vice president of the Virginia Waterman Association. Commercial waterman set their traps in open water, far from the terrapins’ habitat.
“Crabbers don’t want to lose pots at all. They do everything they can to prevent that,” Knott said. “I love the turtles, the last thing I want to do is kill a terrapin.”
It’s recreational crabbers who most often fish along the shoreline, where the turtles live and aren’t aware of the consequences of untended traps.
The Catlett Islands are part of the national estuarine research reserve on the York River. The site is protected and there is not supposed to be any commercial or recreational crabbing activity.
“When these crab traps break away from their lines or are lost during storms, they sometimes tumble into shallow water habitats and there they morph from crab traps into death traps,” Chambers said. “Turtles are inquisitive and they swim into the traps. They drown and unfortunately, they seem to have this social dynamic where one goes in and they just follow.”
Diamondback terrapins are found along the eastern and southern seaboards, according to the Virginia Institute of Marine Science. Their presence is a sign of a healthy ecosystem.
“It’s one of those species, because they require access to open water, they need marshes because that’s where they feed and the female turtles have to get out onto land in order to nest. There has to be habitat connectivity,” Chambers said. “Some people argue they control populations of snails. I’m not sure that’s the case.”
Diamondback terrapins eat a lot of things, he said, and they probably maintain the trophic connections among the food web in the wetland ecosystem.
The turtles' natural life expectancy is up to 40 years.
Derelict crab traps
Tens of thousands of crab traps get lost each year, according to Chambers and VIMS. A 2016 report from the National Oceanic and Atmospheric Administration estimated about 145,000 derelict crab pots — also known as ghost pots — are in the Chesapeake Bay at any given time.
Based on responses from watermen, the report also found between 12% and 20% of all crab pots deployed annually are lost.
Commercial watermen removed more than 34,000 derelict traps from Virginia in a VIMS removal program between 2008 and 2014. At least 10 other states have similar ongoing programs.
“(It’s) sort of like when you go out to the highway and you see the Kiwanis Club cleaning the highway,” Chambers said. “Then the next day it’s completely covered with litter again. There’s a lot of marine debris associated with fishing. There (are) tens of thousands more.”
While the traps do decompose in a year or two, it doesn’t take long to do damage.
Chambers said the trap he found couldn’t have been in the water for more than a few days. The freshly dead turtles ranged in age from 2 to 10 years old and were mostly male because they’re smaller in size.
While there are more of the turtles now than when they were hunted 100 years ago, their population in Virginia is considered “near threatened.”
The turtles may be hit by boats, eaten by predators such as bald eagles or raccoons, which feast on their eggs, but lost or abandoned crab traps remain the biggest threat.
“The Chesapeake Bay is America’s estuary and the … crabbing pressure is greatest in Maryland and Virginia,” Chambers said. “Waterman can go into small tidal creeks and set commercial crab traps, which unfortunately become a real problem.”
But there is disagreement among scientists and watermen when it comes to the real impact of derelict pots.
Donna Bilkovic, a VIMS marine scientist, first noticed the problem in 2006 when she used side-scan sonar to map fish habitats. She began to see square objects on sonar images, and later found out they were crab pots.
She said the lost pots compete with the fishery and decrease the harvest of blue crabs.
“Until that time, no one was really talking about it. We did a small area at the mouth of the York River and there were a lot of pots in a very small area and so that was kind of eye-opening for us,” Bilkovic said. “It’s definitely a bigger issue than just the turtles, although the turtles are heartbreaking. The pots were designed to catch crabs, so they are capturing and attracting a large number of crabs.”
In 2016, she and other VIMS scientists released a report titled “Ecological and Economic Effects of Derelict Fishing Gear in the Chesapeake Bay.”
In 2018, the Chesapeake Bay Stock Assessment Committee of 14 scientists from VIMS and around the country assessed her findings and expressed caution that her report may over-inflate the problem.
Knott, a commercial crabber, has about 150 pots in the water at any given time from about March to November. Commercial crabbers in Virginia can have a license for up to 425 pots.
“Full disclosure, this whole derelict pot issue — I kind of started questioning the science and the numbers. I think there’s a lot of misrepresentation,” Knott said. “I think most watermen feel this way; it’s not as big of an issue as they’re making it out to be.”
Last year, he didn’t lose any pots and he can only remember ever killing one terrapin turtle, after leaving a crab pot hanging on his boat overnight.
Crabbers usually set lines of traps no closer than 300 to 500 meters from the shore, away from the terrapin’s habitat.
“When I got into this, I thought I was an environmentalist. The effects of pollution, when you start seeing that, most of these watermen, that’s how they make their living,” Knott said. “The last thing they want to do is see anything affect their catch, their living and where they work. I’m not saying we don’t have any bad eggs, but for the most part, guys love their water and they want to do everything they can to protect it.”
Both groups recognize a negative impact of derelict crab pots, but disagree on the size of that impact, Chambers said. And they all agree recreational crabbing may result in the most damage to terrapin mortality.
“The terrapin travel around the shoreline and so they’re right in the same areas where people are fishing off of their pier,” Bilkovic said. “It may be even if people aren’t tending their pots regularly — they just leave it at the end of their dock and if they don’t check it regularly then the terrapin are going to perish in the pots.”
There’s no way to know how many recreational pots are out there, Bilkovic said, so recreational fishing and its impact create a lot of open questions.
“There are these occasional, acute mortality events in lost commercial pots against the backdrop of more chronic but low-level mortality in actively fished recreational pots,” Chambers wrote in an email. “Neither group thinks these terrapin losses amount to much — watermen because the mass drownings most frequently occur in their lost pots for which they have no responsibility, and recreational users because each user may drown only a couple terps every year.”
Regulations may help
With marine regulations, the bycatch of fishery gear could decrease and many turtles could be saved.
The Virginia Marine Resources Commission is in charge of commercial and recreational crabbing and it sets regulations for where and when crabbers can crab, how much they can harvest and what type of gear they can use.
In Virginia, people can crab recreationally with up to two pots without a license or a terrapin excluder device. With a recreational license, people can have up to five crab traps. If licensed recreational crabbers use an excluder device, their license is $36 instead of $46, but no one is required to use one.
“The reason excluders are not required commercially is the additional cost, potential escapement of legal-sized crabs, and terrapins are more of an issue in shallow creeks and along the marsh edge than where many commercial crabbers fish,” Ellen Bolen, VMRC deputy commissioner wrote in an email.
Bolen said she’s not aware of any efforts to pass more regulations on recreational crabbers, but the commission has discussed modifying a regulation to improve the identification of recreational gear and to better enforce reporting requirements.
Ghost gear has been a problem in the past, she said, and the commission has funded efforts to remove it. But she knows the degree to which the pots affect the environment and the fishery has been up for debate.
The bycatch reduction device, or TED, are plastic inserts which make the opening into the pots a little bit smaller. Crabs can still get in but because of turtles’ high shells, they cannot fit. There have been a lot of studies that show bycatch reduction devices will limit terrapin mortality and don’t it doesn’t affect the crab catch either, Bilkovic and Chambers said.
“We decreased the overall catch of turtles by like 70% or something like that,” Chambers said. “But again, convincing VMRC that this is something they need to consider is a tough sell.”
Maryland requires an exclusion device for commercial and recreational crabbers and New Jersey requires all commercial style crab pots to be constructed to include a biodegradable panel as a means of escape for marine organisms.
At $2 a device, both scientists and Knott agree all recreational crabbers should be required to use them.
“I think recreational should use it. I think the proximity of where they fish — that’s who’s going to be catching the terrapins,” Knott said. “Two to five pots max is what a recreational fisherman can put in the water, you’re talking $4 for them.”
To require the million crab traps in the Bay to have bycatch reduction devices on them isn’t practical, Knott said, and Chambers agrees.
“Most of the pots are put out where turtles don’t occur,” Chambers said. “So how do you know which of your pots is going to be lost and tumble into a turtle habitat?”
While losing large numbers of terrapins in a single crab trap is a big deal, Chambers doesn’t think they will ever go extinct. They’re resilient and can reproduce for a long time.
Terrapin turtles tend to stay at home, so the populations between states don’t mix. But no one knows exactly how many there are in Virginia.
Although Chambers and his students have only conducted research at Catlett Islands for a short period, they are happy to see the mass mortality event doesn’t seem to have put the terrapin population there in danger.
However, there are 30 fewer turtles.
“The population at Catlett Island is the population at Catlett Island, so if we lose some to drowning in a commercial crab trap then it’s going to take a while to recover from that loss of individuals in the population,” Chambers said.
Chambers grew up on the shore and has seen crab traps kill turtles since he was a child. People are upset by a trap full of dead turtles when they see it, he said.
But because mass mortality events happen at unpredictable intervals, it becomes an issue and then goes away.
Chambers said if people take kayaking or canoeing tours of the Chesapeake Bay, they may run into derelict crab traps in some of the shallow areas. It may be worth it to check them out and see if there are any turtles trapped that they could release.
The only other thing that may help the terrapins, he said, are more requirements to use the bycatch reduction devices.
“Maybe public opinion will hold sway here.”
Martin can be reached at (757)-243-3685, by email at firstname.lastname@example.org or on Twitter at @SaraRoseMartin.