First Ever Triple Nesting Diamondback Terrapin Discovered on Massachusetts SouthCoast

July 10th, 2015

Diamondback Terrapin #825 after Depositing Third Nest of 2015

Diamondback Terrapin #825 came ashore Thursday afternoon, July 9th, on a private beach in Wareham, MA. She deposited a nest in a sand-enhanced “turtle garden” adjacent to the beach; 13 beautiful pink eggs weighing a total of 100 grams. Michele Zollo waited for momma to cover her nest, and then scooped her up for the Turtle Journal team to document.

Terrapin #825:  Three Nests, 39 Eggs, 36 Days

BIG SURPRISE! This day marked her THIRD confirmed nest in 2015. Terrapin #825 nested with the earliest tranche of terrapins in early June, depositing 14 eggs at this “turtle garden” on June 4th. Nineteen days later, #825 returned on June 23rd to lay 12 eggs in a nest very close to her first clutch. Now, after an interval of 17 days, #825 dropped 13 eggs in the same “turtle garden” for a total of 39 eggs in 36 days! We had never before confirmed a triple nester on Massachusetts SouthCoast. We had speculated; we had inferred the possibility, but July 9th marks the first time we have actually had the same turtle in hand for physical confirmation of three nests in one season.

Identification of Diamondback Terrapin #825

Exact identification proves critical in definitive confirmation of events such as these. Terrapin #825′s facial skin markings are quite unique in the SouthCoast system and are easily recognizable, as is her extremely “feisty” behavior.  However, a bit more empirical are her “numerical” marks.  Etched with a triangular file in her marginals are marks that we interpret as #825 in our system of marking; see the image immediately above which can be expanded by clicking.  Each turtle in the Buzzards Bay population has a unique number.  The line through the nuchal (split nuchal), the scars on her first left costal, and the nick in the “10″ marginal provide additional confirmation of her identification.  Digital images at each capture re-confirm these markings, just as digital photographs of her plastron reinforce her identification.  We also take six morphological measurements of length and width at specific points of her carapace and plastron, as well as her girth and her weight at each capture.  In addition to the scientific data these measurements provide, they also confirm Terrapin #825′s identification.  

Broadmarsh Habitat of Diamondback Terrapin #825 in Wareham

Terrapin #825 lives in an extremely protected estuary system off Buzzards Bay in Wareham, Massachusetts. The habitat is called Broadmarsh and lies near Swifts Beach. This area is so well protected that it warms up quickly in the spring, coaxing the first local terrapins out of winter brumation and inspiring the earliest nesters to come ashore.

Michele Zollo (left) and Sue Wieber Nourse Admire Terrapin #825 after Third Nest

A few years ago Michele and Louis Zollo, recognizing that their private beach served as an important terrapin nesting site, augmented the habitat with several tons of sand, creating a safe and inviting “turtle garden.” Michele carefully watches her girls as they waddle in from the bay to deposit eggs from late May through the middle of July. She calls the Turtle Journal team to document the terrapins, and Michele protects nests with predator excluders to save as many of these hatchlings as possible. In late summer, Michele releases them into the abutting nursery salt marsh.

Terrapin #825′s Third Nest of 2015 in Broadmarsh “Turtle Garden”

On June 24th, 2013, an unmarked female terrapin, later marked #825, crawled ashore to nest in the Broadmarsh “turtle garden,” probably for her second nest of the season. The next time we saw Terrapin #825 was June 26th, 2014, when she placed a nest with 15 eggs in the “turtle garden,” again likely her second nest of the season.

Diamondback Terrapin #825 with 13 Eggs in Her Third Nest of 2015

This 2015 year proved a special year for #825 or at least her research colleagues. In the 36 days from June 4th to July 9th, she deposited 39 eggs (~313 grams) in three clutches of 14, 12 and 13 eggs, respectively. She became the first confirmed triple nester on the SouthCoast of Massachusetts.

NOTE:  The average clutch size in Massachusetts is 12.5 eggs which we round up to 13 because half eggs are tough to come by (smile). The normal number of clutches per year for Massachusetts terrapins is two.  So, #825 maintained the same clutch size while laying an extra third nest.

June 4th:  Terrapin #825 First 2015 Nest with 14 Eggs

June 4th, Terrapin #825 at a mass of ~1409 grams came ashore at the Broadmarsh “turtle garden” as only the second nesting terrapin of the year at this site; a leading edge lady. The first nester at this site had beaten her by 30 minutes. She deposited a clutch of 14 eggs and returned to the bay at a mass of 1297 grams.

June 23rd:  Terrapin #825 Second 2015 Nest with 12 Eggs

(2 Broken)

June 23rd, Terrapin #825 at a mass of ~1378 grams came ashore at the Broadmarsh “turtle garden” for her second nest of the season. She deposited a clutch of 12 eggs weighing a total of 101 grams in a nest very near her first nest. Her egg chamber stretched from 5 inches to 9 inches below the surface. She returned to the bay at a mass of 1277 grams.

NOTE: For comparison, in 2014 #825 weighed 1186 grams after depositing a second clutch of 15 ~8 gram eggs. Her mass coming ashore would have been ~1306 grams.

INTERVAL:  19 days between first and second clutches. The average interval between clutches for Massachusetts terrapins is 17 days.

July 9th:  Terrapin #825 Third 2015 Nest with 13 Eggs

July 9th, to the surprise of all, Terrapin #825 at a mass of ~1335 grams came ashore at the Broadmarsh “turtle garden” to deposit her THIRD NEST of the season. She is the only diamondback terrapin to be confirmed as a triple nester on Massachusetts SouthCoast. She dropped 13 eggs weighing 100 grams in a nest a few feet away from her previous two nests. She returned to the bay at a mass of 1235 grams.

INTERVAL:  17 days between clutches.

Her 12 second clutch eggs weighed an average of 8.4 grams each; her 13 third clutch eggs averaged 7.7 grams each. Her mass investment in the first clutch was 8% of her weight, 7% for the second clutch, and 7.5% for the third clutch.

Terrapin #825 Weighed 1235 Grams after Depositing Her Third 2015 Clutch

From her initial mass of 1409 grams to her ending mass of 1235 grams after three clutches, she lost a total of 174 grams while investing 313 grams into her clutches’ egg mass. So, during those 36 days, she also “gained” 139 grams in dietary in-take to make up the difference. Terrapin #815 averaged a gain of 4.3 grams a day from June 4th to June 23rd, and 3.4 grams a day from June 23rd to July 9th.

NOTE:  In considering whether this triple nester represents a special situation, an isolated case or her normal nesting pattern, we should keep in mind that the 2014-2015 winter was cold, snowy and long, and that the 2015 spring was delayed. Nesting on the SouthCoast began on time at the very end of May, neither early nor late.

Confirmation of a triple nester within the SouthCoast terrapin population brings into question certain assumptions about northern-most terrapin nesting and population models. We will need to monitor very carefully other sites within Massachusetts terrapin populations to determine whether this phenomenon is simply a one-off event, or a rare situation, or perhaps relatively normal for the season’s earliest, leading edge terrapin nesters.

CAUTION:  It remains extremely challenging to confirm a three-time nester, given that definitive proof for the first case had escaped our notice during three and a half decades of very intense diamondback terrapin observations within Massachusetts estuaries since 1980.

How to Find a Diamondback Terrapin Nest

June 10th, 2015

Diamondback Terrapin #95 Laying Eggs off Sippican Harbor 

Well, as Turtle Journal has learned with decades of experience, the easiest way to discover a diamondback nest is to find mother terrapin digging, and then patiently, silently, stealthily waiting for her to complete the process.

Diamondback Terrapin #95 Nesting in Sandy Patch at Wrack Line

With a bit of luck and skill, you spot the turtle from a considerable distance and you wait with telephoto lens, so that you don’t disturb her.

Diamondback Terrapin #95 Laying Eggs into Nest Chamber

If she detects you before beginning to actually lay eggs, the terrapin will most likely abandon the nest.

Diamondback Terrapin #95 Laying Eggs into Nest

If she’s already started laying, as with Terrapin #95 above, the turtle may continue until she deposits all her eggs.

Diamondback Terrapin #95, Her Excavated Nest, 12 Perfect Eggs

When she finishes laying eggs, and the terrapin begins to cover and disguise the nest, you can approach.  Here Diamondback Terrapin #95 deposited 12 perfect eggs.

Diamondback Terrapin Nesting Run Tracks & Nest (Top Right)

Sadly for researchers, terrapins are fairly cleaver and stealthy themselves.  So, you learn to read tracks.  Like a tank, turtles leave “tread marks and plastron drags” as they crawl up from the water and meander along the beach.  With the right sand conditions, you get beautiful tracks like those above.  The direction of travel can be discerned from the upside down commas that turtles leave as they push off with their rear legs.

Diamondback Terrapin Nest (Left) and Nesting Run Tracks

And if conditions are just perfect, like this morning, the nest itself shows as an unmistakable pattern in the sand.  Within a few hours, wind and sun will erase all signs, and the nest will disappear.

Excavated Diamondback Terrapin Nest and 13 Perfect Eggs

So, as with all things in life, 99% of success is determined by just being there at the right time.  The challenging part, though, is figuring out where and when.

NOTE:  Diamondback terrapins are a protected species in the Commonwealth of Massachusetts.  Please alert Turtle Journal, 508-274-5108, if you find a turtle or a nest.  We’re always ready to respond.

First Over-Wintered Terrapin Hatchling Emerges @ Tabor’s Schaefer Lab Beach

June 8th, 2015

Sue Wieber Nourse Rescues Exhausted Over-Wintered Hatchling 

While checking for threatened diamondback terrapin nesting at Tabor Academy’s Old Schaefer Lab beach this morning, Turtle Journal’s Sue Wieber Nourse discovered an over-wintered terrapin hatchling meandering in the sand.

Emerged Over-Wintered Terrapin Hatchling Meanders

The Schaefer Lab beach is a documented terrapin nesting site, and hosts the most critical nursery salt marsh habitat for infants and juveniles in the Inner Sippican Harbor.  (See Rare Turtle Nests at Tabor’s Schaefer Lab and Two Rare Terrapin Nests Hatch @ Old Schaefer Oceanology Lab.)

Inaugural Recipient of Jaeger Chair in Marine Studies

Prior to founding Turtle Journal and becoming CEO of Cape Cod Consultants, Sue Wieber Nourse was honored as the inaugural recipient of the endowed Jaeger Chair in Marine Studies at Tabor Academy.  Sue and her advanced marine science students engaged in highly lauded and original scientific research, funded by a prestigious National Fish & Wildlife Foundation grant, that confirmed the existence of threatened diamondback terrapins in Marion and documented previously unknown nesting sites for these rare turtles.  Once on the brink of extirpation, their continued survival stems from this successful conservation initiative.

Sue Rescues Exhausted and Dehydrated Hatchling

This little baby hatched early last fall and opted to remain buried upland rather than venturing into the great wild world.  Given the brutal winter Massachusetts suffered, the hatchling may have chosen wisely.  This morning, though, the terrapin baby exhausted itself trying to reach the marsh through concrete obstacles exposed on this sand starved beach.  She had collapsed dehydrated and weak when Sue rescued her.  The hatchling is recovering at Turtle Journal headquarters, receiving appropriate TLC before being returned to the wild.

TERRAPIN NESTING CONTINUES

Diamondback Terrapin Nesting Run Tracks and Completed Nest

With Sue checking Schaefer, East Marion and Wareham nesting beaches, Don Lewis patrolled other SouthCoast nesting sites.  At one Aucoot Cove site, Don found a half dozen diamondback terrapin nesting tracks from the nighttime high tide.  He discovered the clear sign of two completed nests within inches of each other.

Eleven Large, Pink, Freshly Laid Eggs

This first nest contained 11 very large, pink and freshly deposited eggs in a nest chamber four to eight inches under the sand.  Because of their highly vulnerable location, eggs from this site are harvested and relocated in a protected turtle garden.  When hatchlings emerge, they are released back at the site of their natal nest.

Another Freshly Complete Diamondback Terrapin Nest

Within inches of the first nest, Don spotted signs of the second completed nest.

Ten Big, Beautiful Pink Eggs Harvested from Second Nest

This second nest contained ten large, pink and freshly deposited eggs in a nest chamber about three to six inches below the surface.

Third Nest Laid on the Overnight High Tide

A third nest was discovered about ten feet from the first two.  It contained 11 very large and freshly laid eggs in a chamber three to eight inches deep.  In sum, the Turtle Journal team recovered 32 healthy eggs from this site for protecting in our safe turtle garden.

Great Blue Heron Babies Hatch in SouthCoast Rookery

May 31st, 2015

Great Blue Heron (Ardea herodias) Female and Two Hatchlings 

A storm front charged across coastal Massachusetts this afternoon, May 31st, preceded by dark clouds and gusty winds, and dropping temperatures more than 20 degrees in five minutes.  The Turtle Journal’s Don Lewis & Sue Wieber Nourse were caught by the storm while we visited the SouthCoast great blue heron rookery to document the birth of hatchlings.  Behavior by adult birds on both active heron nests over the past few days strongly indicated that eggs had hatched, but the babies were too deeply set within the nests to confirm their birth.

Female Great Blue Heron and Two Hatchlings during Storm

Two months ago, on March 31st, we trudged down paths still covered with eight inches of snow to document the return of great blue herons to this SouthCoast rookery.  Harsh winter weather conditions had postponed their arrival, just as bad weather had postponed all other spring emergence.  (See Great Blue Herons Return to Rookery for more details.)

Great Blue Heron Female with Hatchling

This nest had been completed destroyed by hurricane force blizzards in January and February.  It and two other nests within the rookery were rebuilt, two by herons and one by a pair of ospreys.  For the full story of the rebuilding process, see Rebuilding Destroyed Nest and Loving Bonds.

Great Blue Heron Mother with Her Two Babies

While we had not been able to confirm births on earlier visits, we got lucky today with the storm.   High winds swayed the northernmost nest and riled babies and mother just enough for us to get a peek of the hatchlings with binoculars and telephoto lens.  Two beautiful great blue heron babies popped up while momma tried to keep them secured within the swaying nest.  The nearby second heron nest likely also contains hatchlings, but the nest is much deeper and it will take a few more days of growth before hatchling heads are visible.

Osprey (Pandion haliaetus) Pair Arrived Late This Spring

The osprey nest within this rookery got a later start.  The pair began rebuilding their winter destroyed nest on April 22nd; see Osprey Pair Rebuild Winter Destroyed Nest.  We anticipate a late arrival for this year’s osprey hatchlings.  (For more information on this osprey pair, see Osprey Love on the Fast Track.)

First Diamondback Terrapin Nester of 2015 on SouthCoast of Massachusetts

May 31st, 2015

First Diamondback Terrapin Nester of 2015 on SouthCoast

This morning the Turtle Journal team discovered the first diamondback terrapin nester of the 2015 season on an isolated and protected Massachusetts SouthCoast beach.  With the first steamy morning of the year on the SouthCoast, Sue Wieber Nourse, Don Lewis and Rufus the Turtle Dog patrolled a sampling of SouthCoast nesting sites in anticipation of finding the year’s first nester.

Diamondback Terrapin Nesting Run Tracks

We were not disappointed at our first beach.  At least two female terrapins had come ashore on the morning high tide that coincided with daybreak.

Diamondback Terrapin False (Test) Nest

We followed one set of tracks as the turtle meandered along the beach, stopping every fifty feet or so to dip a false (test) nest.  We tracked this female as she crawled into the salt marsh without depositing her eggs.

Diamondback Terrapin Female Rests on Completed Nest

Following a second set of tracks, which also zigzagged up and down the beach, we encountered our first nester of 2015, as she rested atop her completed nest.

First Nesting Terrapin of 2015 on Her Completed Nest

As though posing for scientific documentation, she illustrated precisely what a pristine terrapin beach nest looks like.  A perfect way to indoctrinate a new set of terrapin researchers for the 2015 season.

Nearly Completed False (Test) Nest in Developed Community

After searching the remainder of the beach, we visited a second site in a developed residential community.  Here, too, a female terrapin had come ashore on the morning tide, dug a couple of false (test) nests, and then returned to the nearby creek without depositing her eggs.

The diamondback terrapin nesting season has officially begun on the SouthCoast of Massachusetts.