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Don Lewis, Massachusetts Audubon Society,
Fox Island Wildlife Management Area

Late Bloomers — 3 October 2001

The Fall Howl previewed on Cape Cod this weekend and lingered after curtain call for an encore or two.  Thermometers flirted with the 40s, but today by mid-week, summer returned with a gentle southwesterly breeze.  Water temperatures in the creeks had dropped to 56 degrees on Monday morning — a single degree above brumation threshold.  Yet this morning they had bounced back to 62°F.  No hatching nests had been discovered since the storm front took hold.

So, as I passed through my garage lab en route to the jeep for morning rounds, I was quite surprised to see two playful hatchlings staring up at me from the work bench.  Hatchling 415 and 416 both weighed 5 grams and measured about 2.7 centimeters.

On Saturday morning I had checked several marked nests that had not hatched as expected.  Nest 145 had been laid on 10 July by Terrapin 1164 in the east track of 5th Avenue.  The egg chamber had lost integrity when hatchlings began to pip and 8 of 13 eggs had been crushed by traffic, some within hours of emerging.  I harvested the remaining 5 pipped & viable eggs and placed them in a bucket filled with moist sand.  They went into the lab under a heat lamp, sprayed several times daily to maintain humidity.  And the two babies this morning came from this rescued batch.

Hatchling 414 (on the right) proved special.  She showed the same general traits as the Golden Hatchling #259 on the left (The Golden Hatchling — 9 September).  Her plastron had similar spotting and she had the same light tint behind her eyes and on the edge of her carapace.  It’s also interesting to note that Nest 145 is located on the same street as the Golden Hatchling’s nest — within about 50 feet.  And the time difference between hatchings would be consistent if these two nests were Terrapin 1164’s first and second clutch.

When I finally escaped for rounds, I released a batch of hatchlings that had been waiting for a break in the weather and then took advantage of this glorious day to hike Great Island in search of nests.  The Great Island peninsula is a 5+ mile stretch of the Cape Cod National Seashore under supervision of the National Park Service.  It forms the western shoreline of Wellfleet Harbor, protecting the world’s northernmost population of diamondback terrapins from the deeper and colder waters of Cape Cod Bay.  We’re teaming with the National Park Service for the next three years to understand the role Great Island plays as terrapin habitat in Wellfleet Bay.

As I rounded the southern tip of the tombolo (called “the Gut”) tying Griffin Island to Great Island, I spotted an explosion of hatchling tracks, zigzagging in every direction, crisscrossing, circling, and occasionally breaking loose into the marsh.  One set of tracks, probably laid by a hatchling named Sisyphus, slalomed three quarters up a steep dune, tumbled back down, then three quarters up and back down, then three quarters . . . Do you detect a pattern?

With a bit of luck, I traced the lines back to a convergence and discovered Nest 325 about a meter from Nest 085 found by the Park Service on 19 June.  It was a shallow nest with shell remains from 11 emerged hatchlings, 1 still viable egg, 1 pipped turtle that had been killed by fly maggots, and 1 live & pipped baby.  Hatchling 416 weighed 6 grams and measured 2.8 centimeters.  But her shell was warped and deformed with the left side of her carapace caved in.  I decided to hydrate her overnight to see if she balloons back to normal.

Speaking of maggots, the batch I collected a few weeks ago from an infested nest and stored in an enclosed lab dish also hatched. I’ll bring the flies into the Wellfleet Bay Wildlife Sanctuary in the morning to see if they can locate an entomologist to identify this species that has had such a devastating effect on our hatchling population.

But a great day like today deserves to end on a higher note.  And so it did.  This evening between stirring spaghetti sauce and feeding the dogs, I popped into the lab to check on the two morning hatchlings and the one from Great Island.  To my delight another baby from Nest 145 had dug her way to the surface.  Hatchling 417 is a mere 4 grams and only 2.6 centimeters, but she seems raring to go and will join her siblings when they’re released into the south Lieutenant Island nursery marsh in the morning.  We need to take advantage of this warm interlude.  For if past is indeed prologue, the brief preview we had this weekend will be followed by an awfully long run of bone-chilling nor’easters in the very near future.