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WESTBOROUGH - With its many swamps, ponds and rivers, Westborough offers us the exciting possibility of meeting a native snapping turtle.
Why exciting? After all, turtles are slow and lumbering on land.
For that very reason, some excitement is likely if you or your pets encounter a common snapping turtle (Chelydra serpentina) on land. The snapper is likely to feel cornered, simply because it’s on land.
It will probably turn to face you, and it may hiss, lunge and snap its jaws, threatening to bite. It puts on a show of being ready to defend itself. The thing to do, of course, is to realize that you’ve cornered a wild animal and back off.
Snappers have a fearsome reputation, in contrast to our peaceable image of most other turtles. Turtles are famous for protecting themselves by withdrawing – quite literally. For example, our eastern painted turtles (Chrysemys picta) defend their head and legs by pulling them inside their shell, where they’re safe. (Painted turtles are the ones we usually see sunning themselves on logs in ponds.)
Snapping turtles, on the other hand, can’t pull their head and limbs all the way in. Their small-sized lower shell isn’t big enough. They have no choice but to defend themselves on land by biting, just as many other animals do.
In water, snappers are not fearsome. In their element, they are swift and maneuverable. They simply swim away if you unsuspectingly approach or even step on them. Like most other wild animals, they prefer to retreat to avoid trouble. Contrary to what some people think, they don’t hunt the fingers and toes of swimmers.
The other reason for excitement when you find a snapper (or any turtle) on land – especially on a roadway – is concern for its safety in traffic. That dark rock in the road may be a turtle! A big rock could be a snapper. Most drivers have the good sense to avoid running over something that looks like a rock, since rocks aren’t good for vehicles, but unfortunately some turtles become road kill.
Sometimes, drivers may see a “Turtle Crossing” sign, such as on Arch Street near Mill Pond. But these signs are few and far between, and humans have created other dangerous barriers to turtle crossings, such as the local railroad tracks that posed a hazard for the young snapper in this week’s photo.
What are snappers (and other turtles) doing on land anyway? Why does a turtle that lives in water cross a road or trail? One big reason is to get from one wet area to another. For example, snapping turtles may visit woodland vernal pools in the spring to hunt frogs and salamanders that collect there to breed. Human development has created roads and railroads that slice up wetlands and open space into smaller sections, so many animals end up crossing roads in their normal travels. (We see “Deer Crossing” signs more often than “Turtle Crossing” signs.)
Another big reason for snappers (and other turtles) to move over land is to find a suitable nesting area for their eggs. Typically in June, females haul themselves out of the water to search for a sandy place to lay their eggs.
We don’t think of Westborough as sandy, but the retreating glaciers left scattered sand and gravel deposits here and all over the eastern third of Massachusetts some 14,000 years ago. Human sand and gravel operations benefit from them, and turtles find them and dig nest holes with their back legs.
Some holes are false nests, but the female turtle finally chooses one, deposits her eggs, and covers them. Snapper eggs are about the size of ping-pong balls. The female leaves them to be incubated by the warmth of the sun on the sand.
The sun’s warmth also determines the sex of the turtles developing inside the eggs. During a certain early stage, eggs at low and high temperatures (55 degrees F and 77 degrees F) produce females. Eggs in the middle range (say, 73 degrees F) become males. Temperature varies within a nest because some eggs lie deeper than others, so one nest may produce both males and females. What will this year’s cool, wet summer produce?
Turtle eggs may be hidden under the sand, but they’re far from safe. If you walk near a sandy area along a shore or bank, look for what’s left on the ground after a predator raid: slightly rolled, leathery shards of turtle eggs. Some turtle nesting areas can be so covered with the remains of eggs that it seems surprising that any survive.
Skunks are the usual raiders, but raccoons, foxes and coyotes also dig up and eat turtle eggs, usually soon after they’re laid. The false nests that turtles dig may serve to confuse predators.
August and September are the months for baby turtles. Snappers are the size of a quarter when they hatch, dig themselves out of the sand, and head for water. On land and in the shallows, many of them make a meal for snakes, birds, big fish and even other turtles.
Adult snapping turtles are large and well protected from predators by their shell, but it’s legal to hunt them in Massachusetts. Snappers were the traditional meat in turtle soup, a favorite among New England settlers and Native Americans.
How do snappers get through the winter? The fact that they are cold-blooded may be key to their winter survival. Sometime in November, when our ponds begin to ice over, snappers bury themselves in mud at the bottom of a pond. They move little or not at all, and their metabolism – the chemical reactions in their bodies – slows way down. Remarkably, they don’t even breathe, but their skin may absorb some oxygen from the cold water. In April’s warmth, they become active again.
Snapping turtles are survivors. So are turtles in general, dating back 200 million years in the history of life, to the age of the dinosaurs. Turtles survived the mass extinction that killed off the dinosaurs (and 60 percent of the species on Earth) 65 million years ago.
Let’s respect and appreciate our local snappers!
Visit the Westborough Community Land Trust (WCLT) web site to read past Nature Notes columns, check our calendar of events, and download our new trail maps: www.westboroughlandtrust.org.
HARWICH — The Cape has no shortage of curious summer visitors, but one is downright mysterious. It’s the leatherback turtle, and it’s the subject of a research project that bases some of its operations in Harwich Port.
Kara Dodge is a doctoral candidate working in the Large Pelagics Research Center at the University of New Hampshire. She and other researchers regularly hop aboard the fishing boat Sea Holly, owned by Mark Leach, to find, capture, examine and radio-tag the reclusive, endangered sea turtles. In a presentation to a small group of people at town hall last week, Dodge said many questions persist about the species.
|Harwich Port fisherman Mark Leach, pictured with Henry, the first tagged leatherback of 2008. KARA DODGE PHOTO|
Though they grow up to six feet in length, weighing up to 1,500 pounds, leatherbacks have a seemingly meager diet, compared to the sea grass and crabs eaten by other turtles. “They eat jellyfish, only jellyfish,” Dodge said. And since jellyfish are mostly water, leatherbacks need to eat them in huge amounts. Because they have the ability to raise their internal body temperature, unlike most cold-blooded animals, leatherbacks apparently never get cold-stunned like other sea turtles found in these waters.
Leatherbacks spend most of their time feeding in waters relatively close to the surface, but sometimes they dive---and they do it with gusto. One leatherback was recorded diving to 1,270 meters, deeper than every other air-breathing animal except sperm whales. “And nobody knows why they do it,” Dodge said.
Research on leatherbacks began in the 1960s. Before that, when a leatherback was caught off the coast of Cape Cod, it was assumed that the animal had simply strayed from the tropics. Dodge showed an old photo of people posing next to a giant leatherback strung up between two trees as a curiosity. “It was sort of like a sideshow,” she said. Research advanced in the 1980s, when Mass. Audubon researcher Robert Prescott led several studies. Primitive tracking devices were developed, and ultimately confirmed leatherbacks’ impressive annual migration. Females lay their eggs on the tropical beaches of Florida, the Caribbean, and the northern shores of South America, the same beaches where they hatched, and travel north in the summer to the waters off New England and Canada to feed.
Because a leatherback’s carapace isn’t a hard shell, it’s not easy to attach a radio transmitter. At first, the devices were strapped on like backpacks; today’s transmitters are much smaller and more sophisticated, and are attached with a biodegradable tether tied to a hole in one of the ridges of the carapace. After a year of collecting data, the transmitter comes loose and is lost, allowing the leatherback to swim unimpeded. But attaching the radio tag requires first finding and catching the animal.
To do the job, Dodge and her team recruited two fishermen with appropriate boats, equipped with low transoms for hauling the leatherbacks aboard. The boats had to be outfitted with pulpits and towers like a tuna boat, so they can sneak up on unsuspecting leatherbacks. One boat is the Sea Holly, and another is from Woods Hole.
Using cues radioed in by airborne spotters, the crew travels to an area where leathernecks are known to be feeding, and then tries to spot one. It’s no simple task, Dodge said.
“It’s even hard to find whales out there,” she said. Leatherbacks are much smaller, and they’re at the surface only briefly to breathe. “That was our first hurdle,” she said. Eventually they bring the boat alongside a leatherback, and use a custom-designed purse net positioned with a rig that looks like the frame of a giant butterfly net. The turtle is captured and positioned on a special wooden plank which is then hauled aboard the boat. Once on deck, the leatherback gets a physical workup by a New England Aquarium biologist, and then receives a microchip similar to the kind used to identify cats and dogs. It’s not always easy, since the turtle has its own plan.
“You can’t actually stop them from walking around the boat,” Dodge said, so the crew uses cushions and life jackets to keep the animal from harming itself. Then, the radio tag is installed. Each unit costs between $3,500 and $5,000, and provides up to 12 locations each day, transmitting the data to polar-orbiting satellites. The transmitter also collects data on the water temperature and depth of dives. So far, 20 leatherbacks have been tagged, 18 of them off Cape Cod.
Researchers like Dodge want to know why some nesting areas are more productive than others, and ultimately, whether certain “high use areas” might require more careful monitoring. One such area, Cape Cod Bay, appears to pose a navigational challenge for leatherbacks, based on their satellite tracking data.
“We can’t prove this, but it almost looks like they don’t know how to get out of Cape Cod Bay,” Dodge said. That’s a problem, particularly if they get tangled in fishing lines. One leatherback was freed from fishing gear in the bay, only to be found later tangled up again. Another animal died after getting hopelessly tangled in a 10-pot string of lobster traps. With better research, it might be possible to provide mariners with better real-time advisories on leatherback positions, or to suggest fishing gear reductions in certain areas. For the time being, people are encouraged to report sightings of sea turtles in Massachusetts waters by calling 1-888-SEA-TURT. Mariners finding an entangled sea turtle should contact the Coast Guard on marine Channel 16.
Though new data is emerging all the time, the research leaves a number of questions unanswered. Because leatherbacks are most easily observed were when they are laying eggs, there is a much broader knowledge base about females than about males. And very little is known about juvenile leatherbacks, which are very rarely seen. “It’s really hard to protect them when we don’t know where they are,” Dodge said.
Last month, the researchers tagged their first turtle of the season in Nantucket Sound. The crew named the turtle Ethan, after the grandson of Ernie Eldredge of Chatham, another one of the project’s fishermen collaborators. Ethan’s position is posted daily at www.seaturtle.org/tracking/?project_id=423.
Funding for the research comes from the National Oceanic and Atmospheric Administration, the National Fish and Wildlife Foundation, the Cape Cod Commercial Hook Fishermen’s Association, the New England Aquarium and the Provincetown Center for Coastal Studies. The work is expensive, and members of the public are encouraged to adopt Ethan by making a donation of between $25 and $100.
How buying these six fish is encouraging the death of hundreds of loggerhead sea turtles, a threatened species.
Bought any summer flounder, scup, black sea bass, Atlantic mackerel, squid or Atlantic butterfish lately for a delicious dinner?
You won't see this on any label at the fish counter, but the methods used to catch those six fish slaughtered hundreds of loggerhead sea turtles, a threatened species, according to the ocean conservation group Oceana, which is urging the Mid-Atlantic Fishery Management Council to stop the unnecessary killing.
Loggerhead turtles have been listed as a threatened species since 1978 because their numbers are significantly in decline. In 2007, Oceana and the Center for Biological Diversity petitioned the U.S. Fish and Wildlife Service, requesting that a subset of the loggerhead population -- those in the western North Atlantic -- be classified as endangered, affording their habitat additional protection than the species is granted as a threatened species. On Florida beaches, where most loggerhead nesting in the U.S. takes place, there has been a 41% decline in nesting loggerhead turtles since 1998.
In its recovery plan for the species, the Fish and Wildlife Service lists bottom trawling as the first "highest priority threat" to the species, and recommends the use of "turtle exclder devices" in trawling nets to reduce turtle deaths.
Fishermen targeting those six fish in the Atlantic -- summer flounder, scup, black sea bass, Atlantic mackerel, squid or Atlantic butterfish -- from roughly Massachusetts to Florida, with trawl nets are killing 10 times more loggerhead turtles than allowed under the Endangered Species Act, according to Oceana.
Trawl fisheries operate by towing funnel-shaped nets through the water or along the seafloor. "While trawls generally target specific species or groups of species, their unselective nature results in the catch of anything that is too large to escape through the mesh of the nets, including sea turtles," according to Oceana. Turtle excluder devices can reduce turtles killed by 97%, but are only required of summer flounder in certain seasons and certain waters; otherwise, for these six fish species, there is no gear modification used to protect turtles.
"Without an avenue for escape, sea turtles likely drown when captured in trawl fishing gear due to forced submergence," the group claims. "If they do escape, they are often injured from the great stress of being netted and are left more susceptible to further injuries and death."
Bycatch -- as killing of unwanted species in fishing gear is called -- is one factor that lands fish on "do not buy" lists like those published by theEnvironmental Defense Fund and the Monteray Bay Aquarium. Proving just how difficult buying seafood ethically is, though, of the six problematic fisheries identified by Oceana, only Atlantic summer flounder makes it onto both groups' "do not eat" lists. Both black bass and squid are listed as "ok" choices -- not the best, not the worst. Monteray Bay Aquarium lists mackerel as a best choice, and scup as an ok choice, while Environmental Defense Fund doesn't make a recommendation either way.
When Patty was found, she was barely alive; immobilized by shock, blind by burst blood vessels in her eyes. She was fortunate she was rescued when she was and that the National Marine Life Center (NMLC), where she was taken, was so close and able to accommodate her.
Patty is a diamondback terrapin turtle, a species on the endangered species list as threatened in Massachusetts.
“She was brought to us on March 17 cold stunned,” Don “the turtle guy” Lewis, chief operating officer at the Buzzards Bay facility, said
Lewis explained diamondback terrapins go into a state of dormancy during the cold months of winter. They burrow beneath the mud until the warmer weather arrives. If their burrows are disturbed by animals or unintentionally by people, however, and the turtles are exposed to the frigid climate, their bodies will go into a comatose-like state that can cause irrefutable damage and often even death.
Patty is one of the lucky ones.
She was whisked into the veterinary clinic at NMLC, where she was given antibiotics for infection, physical therapy to assist with her limited rear leg movement and plenty of clams and shellfish so she could regain her strength.
She is still not fully recovered, though her eyesight has returned, and, as Lewis pointed out, she is regaining use of her rear limbs again.
“Her condition is improving steadily,” NMLC President and Executive Director Kathy Zagzebski said.
Patty enjoys the comfort of her own tank at the clinic and is even brought out to bask in the sun in the luxury of a kiddie pool beneath the watchful eye of animal care volunteer Juan Bacigalupi.
The plan is to get Patty well enough so she can eventually be sent home to her natural habitat.
Lewis and Zagzebski are hoping for more stories like Patty. They are overseeing the addition of a new hospital at the center and are looking forward to being able to assist more animals and save more lives.
NMLC is a nonprofit marine animal hospital. The goal of the center is to rehabilitate stranded or injured sea turtles, seals, dolphins, porpoises and small whales. Once healthy and able to fend for themselves, the animals will be released back into the wild.
NMLC came to life mainly thanks to a local philanthropic couple who were distressed there were no hospitals in the area to take care of stranded animals.
“Elizabeth ‘Betsy’ Hornor was the National Marine Life Center’s first board chair,” Zagzebski said. “Her passion for NMLC’s mission helped raise awareness and support. When Betsy passed away in 1999, her husband, Townsend ‘Townie’ Hornor took over as board chair. Under his leadership, the hospital began to take shape with some initial design drawings.”
The center has also drawn the attention of two well-known individuals.
“Walter Cronkite was the honorary chair of our first capital campaign, which raised the money for our Life Support System Building,” Zagzebski said.
A longtime resident of Martha’s Vineyard, Cronkite was very familiar with the plight of stranded marine animals in the area. In a 2003 video for NMLC, Cronkite is quoted as saying, “It’s perfectly obvious that as we have more strandings on the beaches of New England, the greater the necessity for the National Marine Life Center.”
Zagzebski also noted that Dr. Bob Ballard, the discoverer of the sunken Titanic, is an inaugural member of the NMLC Advisory Board.
A scientist and ocean explorer, he recognizes the importance of building a hospital for stranded animals on Cape Cod. In the same 2003 video, Ballard is quoted as saying, “Just imagine next time when one has a major stranding, people there will have other options instead of just euthanizing the animals. So, I think
that the sooner we can get this center going, the better.”
“They’re heroes to every marine animal stranded in the area,” Zagzebski said.
NMLC admitted its first patient in 2004.
“It was a loggerhead sea turtle named Eco,” Zagzebski said.
Eco was suffering the effects of having been cold stunned. She had undergone initial treatment at the New England Aquarium. At the National Marine Life Center, her treatment consisted of regular health checks and a proper diet to increase her strength in preparation for release.
The causes of stranding, and subsequent medical and treatment needs, are many and varied, Zagzebski explains.
“Most of the sea turtles admitted will suffer from cold stunning,” she said. “Additional conditions will include pneumonia, bone fractures, arthritis, lesions, and infection. They will require regular blood tests, radiographs, and occasional specialized tests such as CT scan and ultrasound. Many will require antibiotics and antifungal medication as well as specialized procedures.”
She said seals may be admitted year-round, and more frequently in late winter and spring, and may suffer from a variety of conditions including disease, malnourishment, maternal separation, entanglement, and trauma.
Dolphins, porpoises, and whales may also be admitted year-round suffering from a variety of conditions including disease and trauma.
All will require daily monitoring, feeding, water quality testing, and regular health checks.
Zagzebski said one unique condition some dolphins and whales face is mass stranding, when two or more unrelated animals strand.
“Cape Cod sees the third highest rate of mass stranding in the world, and the highest in the U.S.,” she said. “Many of the animals that mass strand are reasonably healthy but suffer significant effects resulting from the stranding itself – abrasions, compression injury, sunburn, bone fractures, dehydration.”
Lewis recalled a pilot whale stranding in 2002 in which a pod of 43 whales were caught in shallow water. Despite the efforts of volunteers and veterinary personnel, all 43 had to be euthanized.
“They were too sick to be released and too large for any rehabilitation pool in the northeast region,” Zagzebski said.
Sadly, she said nearly 99 percent of all stranded marine animals will perish simply because there is no place to bring them.
“The problem is that there is no place in New England to bring a pilot whale or dolphin that needs medical attention,” she said. “There are pools in Duxbury and in Biddeford, Maine, that are occasionally available for a porpoise, but none for larger animals.”
The National Marine Life Center will change that, offering rehabilitative services to animals as large as a pilot whale.
“This will be numero uno for rehabilitation for stranded pilot whales,” Lewis said.
To date, the National Marine Life Center has cared for 21 endangered sea turtles, one harp seal, 29 endangered red-bellied cooters - a freshwater species of turtle - and eight endangered diamondback terrapins, a brackish water species of turtle.
“When our new hospital opens to admit sea turtles Oct. 31, we will be able to admit up to 30 endangered sea turtles, depending on size, at once,” Zagzebski said. “Eventually, when our hospital is fully complete, we will also be able to care for seals, dolphins, porpoises, and small whales (up to three tons).”
There might also be the need to provide temporary shelter and care for an animal not commonly found in the waters off the Cape.
Dennis the Manatee was mentioned. The animal was stranded in the waters off of Dennis a few years ago and needed to be transferred to Florida, where manatees live. Unfortunately, Dennis passed away en route, more-than-likely from the stress he was under.
If the hospital at the center had been operational, Dennis would have been able to take refuge there and could have been attended to before his trip south.
And though manatees are rare in the area, Lewis and Zagzebski said the hospital could aid in stabilizing an animal, thus raising its chances of surviving being transported to another destination for longer-term care.
“We will be a weigh station that can accommodate a one-off situation,” Lewis said. “We will be a temporary home where we can bring the experts to the animal and then transfer it to an appropriate hospital.”
Lewis said the center gets funding “from wherever we can,” and points out that contributions are deductible.
“We’re not an aquarium,” Zagzebski said. “Our goal is to get the animals back into the wild.”
She said she understands and is appreciative of public interest in the animals that may wind up in their care, and the center will try to provide a way for the public to view the animals and keep track of their progress in a way that won’t compromise the animal’s health and wellbeing.
“Just being in the hospital can cause stress for the animals,” she said. “We’ll be trying to give them a quiet and restful place to recuperate.”
“The core of the center is to take care of the animals,” she continued. “Everything else springs from there.”
For more information about the National Marine Life Center, visit www.nmlc.org