Turtle Journal

Over-Wintered Hatchling Deformed by Root Depredation

Knotch, the deformed hatchling rescued from Round Island yesterday, spent the night under a heat lamp, lounging in brackish paludal water — a.k.a. a warm mud bath.  This morning her spirits soared.  As anyone approached her terrarium, she hissed ’em away.  Now, I’ve dealt with loads of hatchlings and with their tiny size, they much prefer to hunker down and keep very low profiles.  When you hit the scales at a quarter ounce, soaking wet, prudence dictates silence when a 150+ pound predator approaches.  Taunting it with a hiss seems like an open invitation to dinner.  But Knotch has her own ideas, and who’s to challenge this feisty little survivor?

Terrapin Deformation Begins to Heal

Most amazing is her recuperative elasticity. The caved-in right side of her carapace, which seemed so horribly deformed yesterday, has ballooned back to near normal. Compare the photo of her last night (top) after a couple hours rehydrating with the one from this morning (bottom).

Hatchling Rescued from Coyote and Root Depredation

Her plastron still remains distorted, but at this rate, I expect to find her fully healed by the day’s end.

Over-Wintered Terrapin Nest Subject to Root Depredation

It’s been a tough few days.  The number of nests explored by predators and found containing desiccated remains has continued to climb.  Six more in the last three days, accounting for another 75 dead hatchlings.  Most of the turtles had pipped, presumably in the fall, but remained in their split shells and underground over the long, cold winter.

Over-Wintered Terrapin Hatchling Smothered by Roots

The nests I’ve excavated since Tuesday been heavily invaded by vegetation.  The eggs and hatchlings were penetrated and had been preyed upon by roots, perhaps to exploit their moisture during this springtime drought.  The last nest I discovered today, over on Round Island in the midst of Lieutenant Island’s nursery marsh, held 16 eggs.  At the top of the nest chamber, hatchlings were smothered in roots.

Over-Wintered Terrapin Hatchling Deformed by Roots

As I gently explored the walls of the nest with my fingertips, I found a turtle outside it egg shell and severely deformed on its right side — as though roots had constricted its growth.  Her eyes were closed and I thought I had uncovered the sixteenth dead hatchling.  But to my utter astonishment, as I lifted her from the nest, she moved her forelimbs to rub her eyes.

 Terrapin Hatchling Survives Coyote and Root Depredation

It is an incredible miracle that, at only 2.75 centimeters long and weighing just 6 grams, she survived predation (both root and coyote), dehydration, and deformation.  What a zest for life!  We dubbed her “Knotch” and brought her back to the lab to improve her chances of survival — as though she needs our help.

 Rescued Deformed Hatchling Responds to Hydration and Heat

After soaking in fresh water and warming under a heat lamp in my makeshift lab, Knotch became fully active without showing the slightest effect of her deformity.  We’ll hold her until the weather returns to seasonal and then release her back into the Lieutenant Island marsh.

AmeriCorps Volunteers Capture Female Terrapin #1070 in Blackfish Creek

To top off a miracle day, AmeriCorps volunteers, working on the horseshoe crab research project in Blackfish Creek, were surprised by a terrapin pair swimming by them.  They ploshed after the male, but he deftly maneuvered into deeper water.  The 11-year-old mature female, weighing just over a kilo, was snagged by Katie.  Not seen previously, she now sports the marking #1070

Canine Depredated and Desiccated Over-Wintered Terrapin Nest

Drought has real consequences on wildlife, and this morning I discovered its brutal effect on 33 over-wintering terrapin hatchlings.  The Cape has been precipitation poor for several months, and while residents have been blessed with pleasant sunshine, the ground has become exceedingly parched.  You may recall on Friday we discovered a live, but seriously dehydrated hatchling in a coyote predated nest on Lieutenant Island’s Turtle Point — along with several desiccated hatchling remains.  So, today we patrolled another section of the south Lieutenant Island marsh to see if there were any other exposed nest sites.

We found three within a 20-foot sandy stretch between the wrack line and an abutting bearberry hill.  In each case, the predator had dug until it reached the first desiccated remains, then broke off the predation and left the rest of the nest chamber intact.

Second Desiccated Over-Wintered Terrapin Nest

As I excavated below the exposed egg, I discovered over-wintering hatchlings which had pipped, but remained inside their shells.  The first nest contained 8 dead, the second had 13 remains and 2 non-viable eggs, and the third held 12 desiccated hatchlings.  None had been disturbed by the predator once the initial dried-out turtle was encountered.

Third Desiccated Over-Wintered Terrapin Nest

Hatchlings were normal in every way, and the condition of the nest chamber, the eggs and the babies precisely matched the pipped babies we rescued in the fall — with one fatal difference.  These were all completely dehydrated, presumably caused by the spring’s lack of precipitation.  Today’s discovery coupled with Friday’s may prompt us to rethink our fall nest strategy.  We had become more aggressive in recovering pipped hatchlings once we found pervasive fly maggot predation last year.  We’ll now need to weigh the pros and cons of over-wintering nests.  True, we lost these nests to drought conditions.  But it seems likely that had not the drought intervened, these hatchlings would have been consumed by predators.

Release of Over-Wintered Hatchling Rescued from Coyote Predation

The morning broke warm and bright with a southwest breeze bathing the Cape in our first wave of summer humidity.  In other words, a perfect day to release Hatchling 001, dubbed Ott, who was rescued from the coyote track yesterday.  Overnight she first soaked in fresh water, and then ambled about her terrarium and burrowed into brackish mud.  Within those few hours she had rehydrated and double her weight to over 6 grams.  And she was a lot more alert and active, too.

Hatchling Disappears under Wrack Line

Released in the wrack at Turtle Point, she crawled over to the cover of a sea lavender and soon disappeared beneath the marsh hay.  Bon chance!

Mature Female Terrapin #363 Swims through the Rip

In Blackfish Creek the tides have swung into mid-phase mediocrity — not very good for turtle observations.  But on the off chance, I dragged the dinghy onto the rip and scanned the channel for passing terrapins.  As the tide reached dead low, a mature female appeared in the rapid.

Terrapin 363 has been under observation by our researchers since June 1996 when she was first discovered during a nesting run on Lieutenant Island.  Then she measured 17 centimeters long and weighed 920 grams.  Three years later and twice last year, #363 was found nesting on Lieutenant Island.  Today was the first time she had been seen in Blackfish Creek.  She now stretches 17.5 centimeters and hits the scales at 1024 grams — over 200 grams (!!!) larger than her weight on 29 June 2000 just after she had laid 14 viable eggs in a Lieutenant Island driveway.

Female Terrapin #363 Meets Mothers’ Day Visitors

With Mothers’ Day Weekend in full swing, there were many beachside visitors this morning, all of whom had the opportunity to meet Terrapin 363 and to hear about diamondback terrapins and Wellfleet Bay’s research and conservancy program to protect this threatened species.

Luck played its trump card today.  In Blackfish Creek, clear skies and clearer visibility allowed us to net a lucky seven terrapins in this morning’s low tide, none of whom had ever been observed before.  And, in the best luck of all, an unplanned visit to Turtle Point afforded us the chance to save a baby hatchling which had been dug out of its over-wintering nest by a scavenging coyote.  Two thumbs up for Friday 11 May.

Steve Smith, Curator of New Bedford’s Buttonwood Park Zoo in 2001

Steve Smith, curator of the Buttonwood Park Zoo in New Bedford, Massachusetts joined me at 0730 to sample the pleasures and excitement of terrapin research in the Land of Ooze.  We were blessed by sunrise temperatures in the low 60s, water temperature also in the low 60s, and a light refreshing 5 knot breeze out of the northwest.

Mature Female Terrapin Paddles through Low Tide Rip

Everything combined for a great outing with fairly good visibility as terrapins streamed through the rip.  Steve netted the first turtle (#1064), a 12-year-old female of 18.55 centimeters length and weighing over 1100 grams.  We traded captures for the next hour with the final tally equaling four females and three males, none of which had previously been seen.

Mature Female Terrapin with Exposed Bone from Traumatic Injury

As the tide ebbed, a terrapin pair nearly slipped by.  The male, covered in light green algae, hit the scales at 240 grams; the female over a 1000 grams.  She had sustained a severe injury to her left side some time ago, as it was well healed.  Bone was exposed along the marginal from mid-point on the left side to the rear quadrant.  The trailing edge of her left rear foot was also affected.

Tiny Over-Wintered Terrapin Hatchling in Coyote Paw Print

As we left the beach, we decided on the spur of the moment to visit the nesting areas and nursery marsh around Turtle Point — even though it’s a month shy of the season — to give Steve a sense of what the habitat looks and feels like.  As we rounded the hill, I mentioned that a coyote had been frequenting this area and digging in the dunes where nests had been laid and hatched last year.  I pointed to a newly excavated spot with the paw print of a coyote still clearly visible in the sand, and then my mouth dropped to the ground.  Hunkered in the shade of this paw print was a terrapin hatchling!  We both thought the worst, because it didn’t move and its eyes seemed shut for good.  But as Steve held the baby in his palm, it began to stretch its neck and legs.

First (Over-Wintered) Hatchling of 2001 from Coyote Depredated Nest

Excavating beneath the coyote print, I discovered 5 non-viable eggs remaining in the nest chamber, 1 deformed dead hatchling which had pipped, and 6 shells from which turtles had emerged.  As we left the site, we discovered another hatchling which had expired along the pathway.  Both this one and the live one we recovered were extremely dehydrated and weighed less than 4 grams.  The surviving turtle measured 2.7 centimeters long and 2.35 centimeters wide.  She sported a desiccated yolk sac on her plastron.  Had we not happened across this secluded spot and peered closely into the paw print, this hatchling would not have made it through the day.

Over-Wintered Hatchling Rescued from Coyote Depredation

Back at Connemara Cottage, I immersed Hatchling 001-01 (named Ott) in fresh water and placed her overnight in a moist, sandy terrarium.  As soon as conditions allow, she’ll be released into the nursery marsh off Turtle Point.