The Boston Harbor Educators Conference will be held this year for the first time on an island in Boston Harbor, Thompson Island, where a full suite of workshops will be offered. Learn about the islands, their history and the biodiversity of the region. Registration will take place at the University of Massachusetts, Boston Campus Fox Point Pavilion at 8:00 am. The Boston Harbor cruise to Thompson Island for workshops and keynote address will depart at 9:00 am and return to UMass Boston at 5:00 pm. The fee is $40 and a registration form can be downloaded from the Massachusetts Marine Educators web site.
Cruise through Boston Harbor Channel Islands
On a clear October day, Boston Harbor is a glorious place to cruise.
As we described earlier in the post, “Rescuing Live Hatchlings from Maggot Infested Nests,” fly maggots devastate threatened diamondback terrapin nests on the Outer Cape. They devour tiny, vulnerable hatchlings as they break their eggshells in the secret darkness of their hidden underground nests. When we encounter a nest infested with maggots, and after we suppress our disgust and repulsion, we aggressively excavate the egg chamber in order to save as many hatchlings as we can.
Terrapin Egg Completely Consumed by Fly Maggots
This Thursday we checked on a nest laid late last June in a new turtle garden off Broadmarsh River in Wareham, 60 miles from nests on the Outer Cape and on the other side of the Cape Cod Canal. Still, once we penetrated the egg chamber the sand resembled an Indiana Jones movie scene with maggots playing the role of snakes. “Maggots,” exclaims the Turtle Guy. “Why does it have to be maggots?”
Maggots in Motion
We ignore the stench and dig quickly through the slithering sand to rescue eight live hatchlings among the devoured remains of eggs and embryos of seven might-have-been siblings.Â
Eight Saved, Seven Depredated by Maggots
The rescued hatchlings appeared lethargic as though traumatized by the experience. But after an overnight stay in clean, moist soil, and a leisurely bath in warm fresh water, they were eager for release into the wild. That is, turtle eager which isn’t quite the same thing as mammal eager.
Hatchling Strolls through Wareham Turtle Garden
The background of the previous video clip shows the exquisite nesting habitat that was created by private homeowners abutting the nursery salt marsh of Wareham’s Broadmarsh River off Buzzards Bay. At their own initiative and their own expense, the homeowners petitioned the Town of Wareham Conservation Commission for permission to create a perfect nesting habitat along a beach front that had become sand starved over the years and had lost all upland nesting potential. These generous homeowners ordered 20 tons of perfectly matched beach sand to make a large nesting site at least 10 inches deep for terrapins to place their clutches. Within a couple of weeks of completing this turtle garden, the first female terrapin had scratched and dug her nest. In total, six nests were deposited in the new sandy turtle garden … all of which were protected by predator excluders. As these new babies mature, they too will return to this turtle garden, ensuring a whole new generation of diamondback terrapins in Broadmarsh River; all thanks to an exceptional family who are dedicated to restoring the Wareham coastal ecosystem for future generations.
The Turtle Journal team gets close to the action to bring you inside the critical natural moment with vivid imagery and compelling video clips.Â
Sue Wieber Nourse Snaps Close-Up of Emerging Hatchling
The Sony DSC-F828 serves as our workhorse research camera with a high quality Carl Zeiss lens and a manual zoom ranging from macro to ~ 135 mm telephoto. We have two F828s, one that shows all the signs of several years of salt water and sand dunes, and a second one with only a single research season under its belt. The F828 produces excellent digital stills, but also provides the capability to switch quickly to medium quality video to document important research events.
Terrapin Hatchling Pips through Its Eggshell
If the F828 is our workhorse, the Pentax Optio W30 with its built-in underwater capability is our pocket miracle maker. The underwater housing serves double duty. Surprisingly, not every field day is sunshine and light. More days than we wish to remember are filled instead with rain, wind and storms. For instance, the leatherback necropsy last Sunday was done outdoors (obviously) in a driving rain storm. The only camera present that could document the post mortem was the Optio W30. Â
Don Lewis Zooms In on Emerging Duo for a Close-Up
Having lost three previous digital cameras to salt water, the Optio W30 is perfect to document all action near, above and below the water line. Its compact shape and light mass allow the camera to slip comfortably into field pockets and even bathing suit pockets. This camera takes excellent macro video clips in QuickTime format and good quality stills when the F828 isn’t around.
Close-Up of the Emerging Duo
The one drawback with the Optio W30 is the LCD screen. The camera fell from my swimming suit pocket about 12 inches onto sandy soil during our June field school. The fall appears to have jarred the LCD screen which has dropped to about 10% functionality. In essence, the camera now is a point and guess. Still, the Optio W30 brings home some sweet imagery … when pointed in the right direction and in the right mode of operation.
The most important instrument for capturing the right shot at the right moment has nothing to do with digital anything. If you can’t get yourself to the perfect spot at the perfect time, your top quality camera will capture a whole lot of sea gulls, sand dunes and fiddler crabs.
One surprise we discovered over the last few years is that diamondback terrapin hatchlings employ a variety of strategies to survive their most vulnerable first year. We had all expected that like sea turtles, terrapin hatchlings scramble from their nests in a beeline for the safety of the thick, rich, robust nursery salt marsh habitat ringing Wellfleet’s most productive nesting sites. The first indications that we may have been hasty in this assumption were hatchlings we found in May and June each year heading DOWN HILL from the uplands toward the salt marsh. The first few observations were dismissed as late emerging hatchlings that had overwintered in their natal nests since we had documented a few nests in May and June that had hatched in the fall, but where some hatchlings had remained until the next spring.  However, once we spotted yearlings heading down slope from the uplands to the marsh this rationalization collapsed.
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Dr. Barbara Brennessel of Wheaton College conducted experiments tracking headstarted hatchlings released in their natal habitat in the Wellfleet Bay system. They were equipped with a transmitter for RDF (radio direction finding) tracking. Although much larger than a normal hatchling due to overwinter feeding, a number of these turtles headed into the salt marsh, behaving precisely as we would have expected a baby terrapin to act. They hid out in the thick Spartina patens, feeding on whatever small critters they could discover in this rich marsh system. However, some number of these headstarts went upland into the vegetated banks abutting sandy nesting areas and the salt marsh. Since these animals were not “pristine” hatchlings, we asterisked their “aberrant behavior.”
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But once we began to track baby hatchlings emerging from natural nests on treks upland, we realized that putting all the data together, many hatchlings race into the robust Spartina patens of the Wellfleet salt marsh system, lots of hatchlings dash under the rimming wrack line between sandy nesting banks and the salt marsh, and still others scale the banks and dunes to explore the vegetative uplands above the most productive nesting sites. These terrapins employ a richer, more complex strategy that offers multiple opportunities for survival of hatchlings in a very raw and unpredictable climate at the northernmost edge of their range.
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This week we watched the emergence of a nest at Turtle Point. Ten live hatchlings left the nest and we followed them with a long-distance telephoto lens to determine how this group might behave once they had tunneled out of the nest. You may recall earlier reporting of tracking hatchlings into the wrack line and others into the Spartina patens (see Tracking Terrapin Hatchlings, http://www.turtlejournal.com/?p=225)
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The first hatchling set out on a solo trek and headed immediately into the vegetation above the nesting bank.
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Solo Hatchlings Climbs into Upland Vegetation
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Three others seemed to wait for this scout to complete its scramble, and then they too scaled the bank to disappear into upland vegetation.Â
Three More Hatchlings Scramble Upslope
The last batch of six hatchlings followed suit, with the final two in this pair offering quite a tag team performance.
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Final Six Head Upland, Too
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Finally, once they had fully dispersed into the uplands, we attempted to find them again. Truth be told, even though we had followed their movements in detail with a long distance telephoto lens, we could only locate four of the ten hatchlings because they were so well camouflaged within the groundcover vegetation.
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Hatchlings Camouflaged in Upland Bearberry Vegetation
No, it’s not a pretty thought. It’s not a pretty sight and it’s certainly not a pleasant experience. But it is the real world of terrapin conservation and so for the serious naturalist, it’s a necessary learning moment. Be thankful that the pictures are two dimensional and that there is no smell-vision key on the video clip.
Research from September 2000 revealed for the first time that a significant percentage of diamondback terrapins nests in the Wellfleet Bay system were being destroyed  by fly maggots. The infestation appears to begin at pipping when hatchlings poke openings in their eggshells allowing the odor of organic material to escape and to attract flies. Since Outer Cape hatchlings remain in their shells and underground for several days after pipping, maggots have the opportunity to attack an extremely vulnerable prey as the maggots work their way through the cracked shell to devour the exposed hatchling.
Pipped and Vulnerable (Upside-Down) Terrapin Hatchling
In most cases, the maggots begin with the umbilicus and enter the main body of the living hatchling through the yolk sac, hollowing out the baby from within. Thus, hatchlings and whole nests are destroyed by these insidious predators underground without ever being exposed for counting by researchers like nests preyed upon by more obvious predators.
Maggots Attacking Helpless Hatchling (Rescued)
Observations over the last nine seasons confirm the 2000 discovery and underscore the severe constraint this predation places on the number of live hatchlings that emerge on the Outer Cape each year. This season (2008) alone has seen more than half of all nests in the critical habitat of Lieutenant Island infested with maggots.
Maggots Consume Hatchling Embryo
Thankfully, the aggressive conservation protocols developed after the 2000 discovery have rescued more and more hatchlings each year from this infestation. By checking nests as they begin to pip and harvesting them at the first sign of maggots, our efforts have significantly increased the number of live hatchlings entering the system since the turn of the millennium. Even after the infestation has begun, our actions can save most hatchlings from the most heavily infested nests. We harvest the pipped eggs and remove all maggots before re-burying premature hatchlings in clean, moist soil to finalize the incubation process. These efforts have rescued thousands of hatchlings that would never have seen the light of day.
Hatchlings Rescued from Maggot Infested Nest
This particular nest on Turtle Point gave away its location by a concavity on the surface. As hatchlings pip and squirm around inside the egg chamber, sand gets displaced and this underground activity shows itself as ripples of the surface sand to the most seasoned turtle researcher. We were able to rescue 10 baby hatchlings from the devouring horde of maggots in this nest, hand-picking tiny maggots from limb cavities and off yolk sacs, then bathing the hatchlings in clean, fresh water for rehydration before release. So, a good day in the Land of Ooze where we saved an order of magnitude better than our goal of one turtle at a time.
