Turtle Journal

Diamondback Terrapin (Malaclemys terrapin) Hatchling

Warmer temperatures, a threat of thunderstorms to trigger barometric changes and gentle showers have enticed tiny Northern diamondback terrapin (Malaclemys terrapin terrapin) hatchlings to emerge from their over-wintered upland sites.  When born in the late summer and early fall, some number of terrapin hatchlings head upland rather than directly into the nursery salt marsh.  They burrow down in coastal dunes, banks and dirt roadways for the winter.  In May, as weather conditions improve, these vulnerable little critters scramble to the surface.

Diamondback Terrapin Hatchling Track

They employ a mathematical technique sometimes called the Drunkard’s Walk, crawling in random directions with slow curves to accommodate the rolling topology of the dunes, seeking to reach safety in the salt marsh.  The trek is treacherous with legions of predators looking for a tasty snack.  Dehydration is an enormous risk in this desert like terrain.  In the track pictured above, the hatchling is traveling from bottom to top.  You can easily detect the tail drag that bisects the track.  We discovered the hatchling track as we patrolled coastal dunes about a quarter mile from the marsh.

Diamondback Terrapin Hatchling “Hiding” on Dune

The tracks continued for at least a tenth of a mile before the hatchling took temporary refuge under some sparse dune plants.  As you can see in the image above, the hatchlings followed the old turtle axiom, “If I can’t see you, then you can’t see me.”  Yet, it is truly amazing how these hatchlings blend so completely into the background and disappear among little camouflaging vegetation.

 Becky Wieber Nourse Discovers Terrapin Hatchling

Fortunately, eagle-eyed Becky Wieber Nourse spotted the hatchling who had obviously tired of its long, long trek.  A cursory examination indicated that the baby had become quite dehydrated by exertion and weather conditions.  We believe it unlikely that this hatchling would have successfully completed its journey to the nursery salt marsh.

Rufus the Turtle Dog Guards Terrapin Hatchling

Rufus the Turtle Dog immediately assumed ownership.  She stood guard over the hatchling to ensure its safety as the rest of the team documented the find.

Don Lewis Documents Terrapin Hatchling in Situ

The team recorded tracks and surrounding habitat.  The specific location was GPS’d and then scientific data on the hatchling itself was derived.

Tiny Diamondback Terrapin Hatchling

Like most Cape Cod hatchlings, this specimen’s carapace (top shell) measured almost exactly one inch (2.54 centimeters).  It weighed a mere 5 grams (less than 0.2 ounce), probably indicating a loss of 15% or more of its original body mass likely due to dehydration.

Diamondback Terrapin Hatchling Carapace (Top Shell)

The carapace (top shell) showed a scutal anomaly with seven vertebral (center) scutes rather than the normal five.  The hatchling also has a split nuchal, the frontmost marginal scute, and a split “90” marginal, the left rearmost marginal scute.  

Diamondback Terrapin Hatchling Plastron (Bottom Shell)

The plastron (bottom shell) still shows the remnants of a once generous yolk sac, “given” to the hatchling by its mother and which provided nutrients to endure the first fall and winter.  The opening for the yolk sac in the center of the hatchling’s abdominal scutes is beginning to close.   To compensate for dehydration and to provide this tiny hatchling with better odds of survival, we allowed it to soak in warm fresh water over night before releasing it directly into the nursery salt marsh that it had struggled so valiantly to reach.

Tiny Diamondback Terrapin (Malaclemys terrapin) Hatchling

We’ve now entered the season for over-wintered hatchlings to emerge and meander to the safety of the nursery salt marsh.  As you walk, bike and drive coastal uplands of Southeast Massachusetts, look down and save a baby turtle.  Who knows?  Saving that one turtle may be the tipping point in saving the world … from the turtle’s perspective, at least.  If you need advice or assistance, call the Turtle Journal team at 508-274-5108.

Sue Wieber Nourse with Buzzards Bay Diamondback Terrapin

An extraordinary day brought a rare turtle event to Buzzards Bay. As temperatures peaked at 59 degrees Fahrenheit at 10 in the morning, we launched kayaks and paddled to two important brumation (winter hibernation) sites in Sippican Harbor.  Even in this murky estuary, the water remained so cold and so clear that we could see right to the bottom.

 Female Diamondback Terrapin Snorkeling for Air

Our timing was perfect to witness an event so rare that few researchers have ever see it.  We watched  as terrapins wiggled out of bottom burrows and swam to the surface for a gulp of air.  Sue Wieber Nourse spotted a female snorkeling in Little Neck Cove, and powered her kayak to the spot.  After gulping for air, the turtle had drifted back down to the bottom, and Sue captured the female diamondback with her long pole net.

Sue Wieber Nourse Examines Female Diamondback Terrapin

In the shadow of Tabor Academy where she created a world class center of excellence for marine science education and was honored by the Trustees as the inaugural holder of the endowed Jaeger Chair for Marine Studies, Sue Wieber Nourse examines her newly captured turtle: Terrapin #30.  More than a decade earlier, Sue’s advanced marine science students at Tabor Academy scored a research breakthrough by confirming the existence of a viable population of threatened diamondback terrapins in Sippican Harbor. Since then she has been engaged in ensuring the survival of these significantly threatened turtles.

Female Terrapin #30 Freshly Emerged from Brumation

It’s a chilly and windy spring on the SouthCoast, and only a few terrapins emerged today, mostly large females.  While we did observe a couple of smaller males, we netted only mature ladies.  The first, Terrapin #30, had never been previously seen.  We have had the other two (#89 and #260) under observation for five and nine years, respectively.  Female Terrapin #30 and the other two females the Turtle Journal team captured today were caked in oozy mud from the harbor bottom.  Their shells were still painfully cold to the touch.

Lion’s Mane Jellyfish in Sippican Harbor

As we paddled through Sippican Harbor this morning, we observed numerous lion’s mane jellies and a bloom of comb jellies.

Female Diamondback Terrapin #30

Female Terrapin #30 was netted by Sue Wieber Nourse in Little Neck Cove as she rested on the bottom, and she is a first time capture.  She is a mature female with smooth growth lines (annuli).  Based on her size, we assess that she is at least 15 years of age.  Terrapin #30 measures 19.6 centimeters (7.7 inches) straight-line carapace length. She weighs 1429 grams (3.15 pounds)

Female Diamondback Terrapin #89

Don Lewis netted Female Terrapin #89 after she surfaced for a breath and then dove back down to the bottom at Head of (Sippican) Harbor. This turtle had first been captured in the same general location on June 7th, 2009. Back then her carapace length was 19.8 centimeters and she weighed 1398 grams.  Today she measures 20.3 centimeters (8 inches) and weighs 1537 grams (3.4 pounds).

Female Diamondback Terrapin #260

Sue Wieber Nourse captured Female Terrapin #260 in Head of (Sippican) Harbor.  She had first been observed on May 30th, 2005 in the same area. Back then she weighed 1386 grams and her shell measured 20.45 centimeters.  Today, Terrapin #260 weighs 1407 grams (3.1 pounds) and measures 20.45 centimeters (8 inches); that is, no appreciable gain in mass or linear size in nine years.  We note that Terrapin #260’s left eye appears unusually cloudy.

Three Female Diamondback Terrapin from Sippican Harbor

After obtaining scientific data on these terrapins, we released them back into Sippican Harbor to rejoin spring festivities.  These brumation sites serve double duty as spring mating aggregations, and with today’s event, the terrapin season is officially underway.  We expect to see these females coming ashore to nest beginning around the last week of May.