Tiny Diamondback Terrapin Hatchling Emerges
By Don Lewis
The first diamondback terrapin hatchling of 2011 emerged on Friday afternoon after 63 days of incubation under the hot summer sands of Lieutenant Island in South Wellfleet. Terrapins are medium sized coastal turtles found along the Eastern Seaboard of the United States. They can be found in Southern New England estuaries and salt marsh ecosystems, and are protected as a threatened species in Massachusetts and an endangered species in Rhode Island. Wellfleet Bay on Outer Cape Cod marks the northernmost habitat in the world for this rare hard-shelled reptile.
In June and July terrapin females crawl ashore from brackish estuaries to lay nests in sandy uplands. They deposit an average of 12-to-13 eggs in each clutch, and usually lay two nests a year. As many as 90% of unprotected nests can be devoured by a host of predators, large and small, from raccoons, skunks, foxes and coyotes to fly larvae, red ants and beach grass roots. Once hatchlings emerge from the nest, they fall prey to these same large predators, augmented by crows, gulls and raptors, as they scramble to the safety of nursery habitat in the salt marsh. As the tide floods in, crabs and fish join the attack on these tiny, yet tasty critters.
"Pipped" Terrapin Egg Nearly Ready to Hatch
When the Turtle Journal team (www.turtlejournal.com) checked a nest that had been laid on 17 June on the south shore of Lieutenant Island, they discovered that one of the top eggs had "pipped." Turtle hatchlings are equipped with a small, sharp egg tooth just below the nostrils. When ready, the hatchling scratches this tool against the egg wall until the shell is pierced. The initial hole quickly oozes albumin (see above), and the baby turtle begins to use its strong, sharp claws to rip and widen the breach. Observations have shown that the whole process can take four to five days from initial "pipping" of the egg until the hatchling emerges, tunnels to the surface and scrambles to the safety of nearby vegetation.
As the team probed deeper into the nest, they discovered an egg that had been "pipped" for several days with a substantial tear in the shell and a hatchling itching for freedom. As soon as sunlight touched the baby's face, it sprang to action and squirmed free of its egg shell. This hatchling had incubated in its egg for 63 days. The average incubation time for mid-June nests ranges between 55 and 75 days, depending on summer temperatures and exposure of the sand atop the nest to direct sunlight.
Terrapin Hatchling Season Begins in Southeastern Massachusetts
Friday's discovery is a harbinger of things to come ... and to come quickly. Once hatchling emergence begins, it kicks instantly into high gear. The beautiful warm sunshine forecast for this weekend will cue hundreds of hatchlings to tunnel to the surface and scramble for safety. Predators will be similarly cued to hatchling emergence, and those few feet from the exposed nest in sandy uplands to camouflage in thick vegetation are the most dangerous passage in the life of a terrapin. As you stroll the shoreline this weekend, look down and keep a sharp watch for tiny babies bubbling to the surface of dunes, coastal banks and dirt paths and roadways. If you discover a baby turtle, give a call to the 24/7 turtle hotline at 508-274-5108.
Mass Audubon and Turtle Journal have been involved in diamondback terrapin conservation from the South Coast of Massachusetts to the Outer Cape for more than three decades to reverse the decline of this threatened species. Hundreds of terrapin nests that were discovered in June and July by researchers and volunteers have been protected with predator excluders (chicken wire cages). If you run across one of these protected nests that dot the Wellfleet coastline, and you detect a baby turtle within the cage, give a holler to the hotline.
Not only diamondback terrapins are hatching. Other Massachusetts turtle species, such as painteds, spotteds, boxes and snappers, are also ready to emerge throughout the Commonwealth.
If you're looking for a nature walk that might offer the chance to spot one of these exquisite hatchlings, the Goose Pond or the Bay View trails at Mass Audubon's Wellfleet Bay Wildlife Sanctuary off West Road in South Wellfleet would be a perfect choice.
For more information about this topic, for access to illustrative images or to arrange an interview, contact Don Lewis at (508) 274-5108 or email him at theturtleguy@comcast.net. The embedded images are the sole intellectual property of Don Lewis and Sue Wieber Nourse who authorize the use of these photographs to illustrate this story.
Don Lewis is executive director of the Massachusetts Association of Conservation Districts; Sue Wieber Nourse is a marine researcher, textbook author and master educator. Known as the Turtle Guy, Don and his spouse and partner, Sue Wieber Nourse, have led research, rescue and conservation activities on Cape Cod and around the globe for more than a decade. They own and operate Cape Cod Consultants, an environmental solutions company that specializes in wildlife management and habitat assessments that protect nature while enabling dreams. Lewis and Wieber Nourse document the nature of coastal Massachusetts on their web site, Turtle Journal (www.turtlejournal.com).
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