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Terrapin “Cover Girl” Resurfaces after 15 Years

Tuesday, May 20th, 2014

Diamondback Terrapin 829 Cover Girl 

Every turtle has a story to tell and a lesson to share.  While researchers eschew bonding with wild animals, the truth is there’s always a special critter or two through the years that you remember fondly.  Female Terrapin #829 played such an important conservation role as the face of Cape Cod diamondback terrapins that she holds a special place in our hearts and minds.  In 2000, her glossy photograph graced the cover of Natural New England Issue #2 to represent this species in trouble on Old Cape Cod.  Her captivating beauty, which appeared in countless publications and multimedia presentations, helped inspire a community conservation effort that turned around the outlook for diamondback terrapins on the Outer Cape … and has helped preserve fragile coastal uplands and restore critical salt marsh systems.

[ASIDE:  Yes, we know.  That’s political science, not hard science.  But it’s Turtle Journal’s thesis that effective conservation is the nexus of sound science and smart political science.  Each on its own is necessary, but insufficient.  You must do both with equal skill and intensity.]

Diamondback Terrapin 829 in Blackfish Creek

We chose Terrapin 829 for this role because of this wonderful photograph taken on the stunning brilliant day of her first capture on September 26th, 1999.  The backdrop is Blackfish Creek, Wellfleet Bay and Great Island in the far background.  On this perfect fall day, as most Outer Cape terrapins were preparing to enter brumation, healthy Terrapin 829 weighed 1394 grams, her carapace measured 19.6 centimeters and her plastron spanned 17.6 centimeters.  Based on our Outer Cape growth model, we estimate her age in 1999 as around 30 years.

Proof of Concept:  Capturing Terrapins from a Kayak (1999)

We captured Terrapin 829 from a kayak with a 10-foot dip net at 7:15 in the morning in her native Blackfish Creek.  She was one of the first terrapins netted in this proof-of-concept approach that subsequently became the principal methodology for water captures on the Outer Cape and SouthCoast.  Terrapin 829 was also the next to the last active terrapin we observed in 1999; all others had already burrowed under the ooze for a long winter’s snooze.

Terrapin 829 in 2002 with Traumatic Shell Damage

On June 3rd, 2002, we sampled terrapins in Wellfleet Bay’s prime mating aggregation: Chipman’s Cove.  We netted ten female terrapins; nine were first time captures.  Terrapin 829 proved the only recaptured turtle. Since we first saw her in September 1999, she had suffered traumatic shell damage to her front left quadrant, probably caused by an encounter with a boat.  See Life After Celebrity originally published in Terrapin Diary and now posted on Turtle Journal.

Terrapin 829 15 Years Later (May 2014)

On Friday, May 16th, the Turtle Journal team visited the Chipman’s Cove mating aggregation for the first time in the 2014 season.  We waded into the flooding cove and hand-netted six diamondback terrapins:  two recaptures and four first timers.  The very first turtle we netted was the quite distinctive Terrapin 829, easily recognizable by the injury to her left front marginal scutes.

Terrapin 829 Still a Cover Girl Beauty at 45!

In 15 years Terrapin 829 has grown 25 millimeters in carapace and plastron lengths, while maintaining the same weight.  She’s still quite a beauty, especially when she shows her right profile and hides the cracked marginals.  We suspect her recent glossy image will still grace many a publication and more than a few multimedia presentations.

Still Hot — Female Terrapin 829 Pursued by Handsome Male

How hot is she?  When we observed Terrapin 829 paddling through the shallows of the Chipman’s Cove mating aggregation on Friday, she was hotly pursued by a handsome male terrapin.  Note the gender dimorphism of diamondback terrapins illustrated by this pairing. Female Terrapin 829 weighs 3 pounds and is 7.8 inches long; the large mature male, #6103, weighs 2/3 pound and is 4.9 inches long.

Posted in Habitat, Marine Science, Turtles, Wild Animals | Comments Closed

Saving Elvers on the SouthCoast of Massachusetts

Sunday, May 18th, 2014

Slightly Pigmented (American Eel) Elver (Anguilla rostrata)

The Turtle Journal team had an opportunity to play a role in the life cycle of American eels (Anguilla rostrata) this weekend, to learn a lot about tiny elvers, to document the huge challenges to their survival, to engage in some hands on field research and discovery, to save a few hundred juveniles and to work towards smoothing the journey for new generations of American eels within the SouthCoast watershed.  Like so much else in the natural world, we humans hold the future of this species in our own hands, just as Sue Wieber Nourse holds a tiny elver in her hand as we lift it past an obstacle to its survival. 

American Eels Spawn in the Sargasso Sea

The epic journey of the American eel (Anguilla rostrata) is a literal ocean odyssey with few equals in the marine world.  American eels spend their lives in fresh water ponds and estuaries on the East Coast of North America. When the time comes, and eels can live long lives, mature adults leave the ponds where they spent their lives.  They slither through bog, creek and river to reach an estuary as they begin their long, long ocean journey to the Sargasso Sea.

 IF YOU HAVE AN iPAD & CAN’T SEE VIDEO, CLICK HERE.

American Eel Life Cycle by GRYPHON Media Productions

[This brief video funded by Unamaki Institute of Natural Resources (Cape Breton) and Parks Canada provides an excellent overview of the life cycle of the American eel (Anguilla rostrata).]

It’s a one way trip.  Adults will consume all their energy stores to produce and externally fertilize eggs in a giant spawning in the Sargasso Sea.  Each female can lay millions of eggs and dies after egg laying.  When hatched, the larvae develop into leptocephali and float in the currents like tiny leaves, ever moving closer to North American shores where they metamorphose into glass eels.  As they enter estuaries and fresh water systems, they develop pigment and become elvers.

Tiny American Eel Elvers Scale 10-Foot Water Control Device

In this epic journey from Sargasso Sea in the middle of the Atlantic Ocean to a local SouthCoast pond, elvers must traverse enormous challenges, the most serious being obstacles erected by human development:  dams, hydro-power systems, water control regimes, fast flowing culverts, flood control devices and so on.  After a perilous trek of thousands of miles from the mid Atlantic ocean, tiny vulnerable elvers get stopped within inches of their goal by human contraptions for which evolution never prepared them.  And that might be the journey’s tragic end were it not for their extraordinary tenacity and persistence … augmented with a critical assist from caring and knowledgeable locals.  One such local planner called Turtle Journal on Friday, May 16th, to report that elvers had been sighted at a SouthCoast cranberry bog as they were trying to scale a 10-foot vertical water control device.

Hundreds of Tiny Elvers Squiggle Straight Upward

On Saturday morning we visited the bog and found hundreds of tiny elvers wriggling up the vertical 10-foot device in an attempt to reach the fresh water pond where they would spend their lives.

IF YOU HAVE AN iPAD & CAN’T SEE VIDEO, CLICK HERE.

American Eel Elvers, May 2014

We documented the process, and later spoke with the bog operator about potential assists to facilitate the elvers’ passage through the water control device.  Years ago the bog operator had constructed a concrete and rock “ladder” with continuous water flow leading from the creek to the pond.  We observed many elvers using this passage to reach the pond.

Tiny American Eel Elver and Don Lewis’ Thumb for Sizing

While no longer glass eels because they have become somewhat pigmented while moving through estuary and creek, the overwhelming number of elvers were quite small as indicated by the photograph above with a Don Lewis’ thumb to gauge sizing.

~ Eighteen Inch American Eel Climbs Ladder into Pond

As we watched the concrete “ladder,” a large (~ 18 inch) American eel slithered up the stairs.  We suspect that at this stage of development it would be called a yellow eel.

~ Eighteen Inch American Eel Slithers into Pond

After climbing the concrete “ladder,” the eel slipped into the pond and lazily powered itself into deeper waters.  During the two hours we observed this ladder, elvers of various sizes and stages of development made the passage from creek to pond.  First, they scaled a six foot tight rocky passage, then they completed the transition by climbing the wet concrete stairs.

Thousands of Elvers Obstructed by Newly Installed Culvert

Saturday night we pored over watershed maps to trace the path from the bog to Buzzards Bay through Aucoot Cove and associated creeks, streams and bogs.  We identified the likely pathway for the elvers and highlighted a potential obstacle to their passage.  On Sunday we visited the site of the potential blockage, and Sue Wieber Nourse observed thousands of elvers backed up by a newly installed, gushing culvert.

1/2 Gallon Pail Yields ~ Hundred Obstructed Elvers

How many elvers were frustrated by the new culvert?  We dipped a half gallon pail into the creek and quickly pulled it out.  In that brief instant, a hundred tiny elvers flooded into the half filled pail.  We contacted the planner for the site immediately, alerted him to the situation and talked about potential quick and long term fixes.

A Boost for a Hundred Elvers

Alas, we still had our 100 elver bucket.  It reminded me of the story of the old man (or sometimes a young girl) and a beach full of starfish.   If you’d like to read a version of this story, click here.  Yes, we couldn’t help every elver make that passage from creek to pond.  But we sure could give a huge boost to the 100 elvers in our plastic sampling bucket.  If just one or two or five or ten of those 100 elvers made it back to the Sargasso Sea and laid millions of eggs … Well, perhaps our quixotic gesture wasn’t as foolish as we originally thought.  In fact, since we’re saving the world one turtle at a time, maybe we can save the world one yellow elver bucket at a time, too. We lugged the bucket across the trail to the pond and poured 100 elvers into their new home.

Posted in Habitat, Marine Science, Marine Species, Wild Animals | Comments Closed

Terrapin Hatchlings Emerge from Uplands

Sunday, May 11th, 2014

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.

Posted in Habitat, Marine Science, Marine Species, Turtles | Comments Closed

Exciting Terrapin Event on SouthCoast

Wednesday, May 7th, 2014

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.

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Juvenile “Blue Bloods” Emerge

Tuesday, April 29th, 2014

Sue Wieber Nourse Examines Two Juvenile Horseshoe Crabs

Juvenile horseshoe crabs rocked Outer Cape salt marsh creeks during the April 28th flood tide.  Turtle Journal celebrates the emergence of these true “blue bloods” each spring.  We have been checking for their awakening since late March, but this year’s cold spring temperatures have prolonged their winter slumber.  (See Salt Marsh Awakening: Juvenile Horseshoe Crabs Active on Outer Cape, April 18th, 2013 and Mid-March Emergence of Juvenile Horseshoe Crabs, March 19th, 2012.)

Two Juvenile Horseshoe Crabs (Limulus polyphemus)

Admittedly, the horseshoe crabs we discovered this morning were a bit sluggish in today’s chilly water temperatures, under cloudy skies and with a stiff northeast ocean breeze.  Today’s specimens ranged in weight from a little over 1/2 ounce (17 grams) to 4 1/3 ounces (122 grams).  The horseshoe crab’s exoskeleton (shell) does not expand.  To grow, horseshoe crabs molt, as many as five times in the first year, three in the second, two in the third, and once a year thereafter until maturity is achieved.  It takes sixteen and seventeen molts respectively over a period of nine to eleven years for a male and female horseshoe crab to reach maturity.

Tiny 1/2 Ounce Juvenile Horseshoe Crab (Limulus polyphemus)

Ventral View of Juvenile Horseshoe Crab (Limulus polyphemus)

Measuring Tiny Juvenile Horseshoe Crab (Limulus polyphemus)

The tiniest horseshoe crab measured less than 2 1/4 inches (~ 6 centimeters) long (minus its tail/telson).  As you may know, horseshoe crabs are the true “blue bloods” of the animal kingdom with blood composed of copper rather than iron.  This limulus blood yields a unique and powerful gram-negative bacterial detector that saves human lives.  Horseshoe crabs have also been extremely valuable in the research of vision with both compound and simple eyes, as well as facilitating many other scientific and medical breakthroughs.

Larger (4 1/3 Ounce) Juvenile Horseshoe Crab

Ventral View of 4 1/3 Ounce Juvenile Horseshoe Crab

The largest juvenile horseshoe crab we encountered this morning measured about three times the length of the smallest and hit the scales at 4 1/3 ounces.  The ventral (bottom) view of this juvenile horseshoe crab clearly shows the five walking legs on each side, the forward feeding pincers (Chelicerae), and the rear book gills.   The telson (tail spine) is pointed directly at the camera.

Juvenile Horseshoe Crab (Limulus polyphemus)

Juvenile horseshoe crabs are delightful to watch as they plow through the sandy bottom of creek channels.  As adults, horseshoe crabs are Nature’s auto-tillers, constantly refreshing coastal tidal and inter-tidal flats.  Appearing as ancient as the earliest trilobites, horseshoe crabs stir awe in the Turtle Journal team.  Sadly, humans have harvested these valuable critters to the edge of extinction, extirpating them from one estuary after another, impoverishing our entire tidal and inter-tidal eco-systems, and driving shorebirds that survive epic migrations on nourishing horseshoe crab eggs to the brink, as well.  So, it is especially joyful each spring to find juvenile horseshoe crabs as we continue to hope for sanity to prevail among state and federal wildlife managers of this important foundational marine species.

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