Archive for the ‘Turtles’ Category

Diamondback Terrapins Gather in SouthCoast Mating Aggregation

Friday, May 15th, 2015

Beautiful Female Diamondback Terrapin #601

Thursday morning, May 14th, broke beautifully.  A gentle breeze nudged southerly temperatures into Buzzards Bay. Unfiltered sunshine did the rest, baking low tide drained mud flats into steamy saunas. Unquestionably a day for turtles!

Lucky Female Terrapin #7

We launched kayaks from Town Landing and headed for the major Sippican Harbor mating aggregations. Paddling through flat waters, we observed gorgeous female and handsome male diamondback terrapins gathering. Clearly, numbers were still light as many ladies and gentlemen lingered in oozy shallows, preferring to bake in soft mud baths rather than bask in the open air.

Handsome Male Diamondback Terrapin #28

Guys were snorkeling in the main channel, waiting for damsels to arrive. We spotted a few females on the bottom under mud mounds and gently tapped them on the shell, interrupting their sauna dreams. Needless to say, they were NOT amused … by neither the tap nor the dip net that quickly engulfed them.

Lucky Female Terrapin #7 Snorkeling in Shallows

One of the captured turtles had a very interesting story to tell. Female Terrapin #7 had been rescued in Central Massachusetts last year and released in Sippican Harbor on July 5th.  When we examined her yesterday after a summer and full winter in Buzzards Bay, she proved in great condition, having gained 162 grams (14% increase) and having found her way into the most popular mating aggregation in the area.

Juvenile Female and Adult Male (Right) Terrapins Sloshing in Shallows

None of the terrapin females yet shows palpable egg development, but the season is young, and mating aggregations are just beginning. We also spotted a number of very young juveniles playing hide & seek in “quick mud” tidal flats in water depths less than 2 inches.

TURTLE ADVENTURES @ EARTH DAY 2015

Sunday, April 26th, 2015

Children Admire 9-Year-Old Diamondback Terrapin

The Buzzards Bay Action Committee sponsored an Earth Day celebration on Saturday, April 25th in Fairhaven on the SouthCoast of Massachusetts.  The Turtle Journal team presented all local turtle species, marine & fresh water, that have already awoken from winter slumber to the delight of children from three to eighty-three, offering a great hands-on learning experience about turtles and nature for Earth Day 2015.

Don Lewis Demonstrates Female Diamondback Terrapin

Diamondback terrapins, spotted turtles and painted turtles greeted visitors and became a central attraction as folks spread out on the floor to get up close and personal with these reptilian guests.  Guests learned about turtles’ life history, their habitat, their predators and their survival status.

Earth Day Children Learn about Threatened Diamondback Terrapin

Using actual field research gear, kids measured and weighed turtles as junior researchers, and found out about obstacles to their future survival.

Turtle Hunt:  Male Spotted Turtle Makes Break for Freedom

Turtle Hunt:  Joy, Delight and Amazement

The highlight of the day came when the male spotted turtle decided to make a break for freedom.  He nimbly scurried under tables, around chairs and made a bee-line for the exit.  Like a western posse, children crawled on all fours to follow the turtle’s movements and to make sure he was safely apprehended.  The sheer joy of discovery and delight of this adventure glowed brightly in their eyes.

Kids Learn about Hard Shells, Soft Skin and Warm Hearts

The experience proved awesome.  Kids who had never seen a turtle, began by wondering if it were real or a toy.  As children touched her hard shell, stroked her soft skin and felt her sharp claws, they gained a first-hand understanding of the nature of turtles, and hopefully the nature of Nature itself.

All Photographs Courtesy of Sue Wieber Nourse of Turtle Journal.

FIRST ACTIVE DIAMONDBACK TERRAPINS 2015

Saturday, April 18th, 2015

Sue Wieber Nourse Examines Female Diamondback Terrapin #278

Today is the spring day we have been waiting for since last October. After a blustery fall that drove a record smashing 1200+ cold-stunned sea turtles onto Cape Cod shores. After a record breaking winter dropped more than 9 feet of snow on Massachusetts. After a faux spring with temperatures lingering in the 30s and 40s, and until yesterday still sporting patches of snow. After all that and much more, today spiked to 70 degrees on the SouthCoast of Massachusetts. Perfect fluffy clouds skirted along the horizon pushed by southwesterly winds. The only thing that could make it more perfect would be the emergence of the first active diamondback terrapins of the year. And that, too, came to pass this glorious April 18th, 2015.

Sue Wieber Nourse Nets First Terrapin of 2015 (#278)

As temperatures began to climb through the high 50s, the Turtle Journal team loaded kayaks into the CRV and launched from the Marion town landing with long poled nets to explore Sippican Harbor for diamondback terrapins. We spotted a couple of nervous males snorkeling around the mating aggregation, but they dove into the oozy bottom as soon as we approached. We paddled to Little Neck Cove and Sue Wieber Nourse hit pay dirt.  She saw a large female crawling along the bottom in pursuit of a juicy green crab. Sneaking up from behind, Sue netted the big girl who didn’t even pause in swallowing her tasting crab treat.

Sue Wieber Nourse Identifies Female Terrapin #287

Examining the first terrapin of the year, Sue identified her as a previous capture, #278, a very large and healthy female. Sue deposited her behind the kayak seat and continued exploring Little Neck Cove.

Don Lewis Nets Male Diamondback Terrapin #110

A few feet away, Don Lewis paddled slowly over a series of emergence holes that terrapins had been using for winter hibernacula. He saw a turtle creeping along the muddy bottom and stretched his net to scoop up a male terrapin whom we had never previously captured.

First Time Capture Male Diamondback Terrapin #110

We marked this new, but ancient male as Terrapin #110. He measured a very large 13.55 centimeters straight-line carapace length that puts him in the top percentile for SouthCoast males. He weighed a respectable 368 grams, and noteworthy, the tip of his tail had been lost somewhere in his long history. His “mustache” is a thing of beauty of which even Poirot would be proud.

Recaptured Female Diamondback Terrapin #278

Sue’s female Terrapin #278 had last been seen a decade ago (!) on 25 June 2005, swimming in this same cove. Based on her estimated age then, she’s over 21 years old today. In 2005, she measured 18.8 centimeters straight-line carapace length and weighed 1112 grams. Back then we took scat samples that indicated she had been feasting on mud snails, tiny bivalves, mud crabs, small fiddler crabs and bushy bryozoan. Today, she measured 20.0 centimeters carapace length and weighed 1399 grams.  She had tiny barnacles all over her vertebral scutes.

Male Spotted Turtle #127

April is busy season for turtle researchers on the SouthCoast. We drove directly from the Sippican Harbor to a nearby wetlands bog to check on spotted turtle activity. There we discovered male Spotted Turtle #127 whom we had previously observed just six days ago. He looked fine and had added 2 grams to his weight.

All things considered, a perfect spring day yielded a perfect turtle day for the Turtle Journal team.

POSSIBLE TRANSITIONAL ADULT SPOTTED TURTLE

Friday, April 17th, 2015

Male Spotted Turtle #156 Possibly in Gender Transition 

As reported earlier this week (see Possible Gender Changes in Adult Spotted Turtles on SouthCoast of Massachusetts), we detected possible gender changes in two adult spotted turtles, #206 and #207, first observed in April 2014 with female chin and neck pigmentation and then documented in April 2015 with male pigmentation and other male gender characteristics.  Yesterday, April 16th, we captured a new spotted turtle (#157) at the same bog.  This turtle, that we have identified as male, presented with possible transitional pigmentation of the chin and neck.

Male Spotted Turtle #156 with Possible Transitional Pigmentation

Spotted turtles feature gender dichromatism with females showing a brightly (orange) colored chin and neck and males sporting dark, drab chins and necks.  Spotted Turtle #156 appears to be in transition.  The chin is not bright orange and has not yet become drab black.  The neck sports some “bumps” that still hold an orange pigmentation, but is dominated by darker color.

Spotted Turtle #157 with Slight Abdominal Cavity

We assessed Spotted Turtle #157 at 11+ years old based on annual growth lines and size.  The turtle measured 10.22 centimeters straight-line carapace length, 7.84 centimeters maximum width, and 8.65 centimeters plastron length.  The weight was 144 grams.  With an abdominal cavity and the location of the anal vent, we identified #157 as a male.

Close Up of Spotted Turtle #157

Although it seems to us to be a turtle in transition, we have no history for this individual since 16 April 2015 marked its first capture.  Now that we have documented its appearance, we look forward to compare future observations of chin and neck pigmentation.

POSSIBLE GENDER CHANGES IN ADULT SPOTTED TURTLES ON SOUTHCOAST OF MASSACHUSETTS

Tuesday, April 14th, 2015

Spotted Turtles #206 & #207 Changed from 2014 to 2015 

On April 11th we recaptured adult Spotted Turtle #206 at 11:15 in the morning at a SouthCoast bog.  At 3 in the afternoon we recaptured adult Spotted Turtle #207 at the same bog.  We were surprised at the changes illustrated above that suggested a transformation from female to male gender characteristics.  One such turtle would have been a deep puzzler, but two turtles, one after the other, proved a real shocker to the Turtle Journal team.

CLICK PHOTOGRAPHS FOR HIGHER RESOLUTION

Typical Male Spotted Turtle #119 (April 2015)

Typical Female Spotted Turtle #131 (April 2015)

One of the defining characteristics of spotted turtles is gender dichromatism with females flashing a bright colored chin and neck, and males sporting a dark, drab chin and neck.  Yes, there are other gender signs, such as the thick, large male tail, the more posterior location of the male anal vent, and the male concavity of the plastron’s abdominal scutes.  Still, color difference is a quick and easy indication of gender.  All of these gender characteristics are illustrated in two images immediately above for Male #119 and Female #131.

So, when those color characteristics change for an adult spotted turtle, or two adult spotted turtles, in a single year, it gets our attention.

Spotted Turtle #206 April 2014 and April 2015

We first observed and marked Spotted Turtle #206 at the SouthCoast bog mating aggregation on the morning of 6 April 2014.  We next saw this turtle 11 April 2015 basking with female Spotted Turtle #150. #206 had experienced a significant growth spurt and had changed its chin and neck color.  We confirmed this turtle’s identity by its individualized marginal notches (its number), as well as photographs of its carapacial scute shapes and the positions of its yellow dots.

Spotted Turtle #206 Plastron April 2014

In April 2014 we assessed this turtle as approximately 6 years old based on size and on annual growth lines.  #206 measured 8.71 centimeters straight-line carapace length, 6.69 centimeters maximum width, and 7.76 centimeters plastron length.  The weight was 96 grams.

With an orange chin and neck, we noted her gender as female, but in the observation remarks, the recorder wrote, “Female with big tail.”

Spotted Turtle #206 Plastron April 2015

When we saw #206 next on 11 April 2015, this turtle had transformed its chin color to drab darkness and its neck color to dark, as well.  The growth spurt proved substantial.  The straight-line carapace length increased to 10.14 centimeters (nearly 1 1/2 centimeters), the width measured 7.51 centimeters, and the plastron length reached 8.78 centimeters.  #206 weighed 128 grams (a 1/3 increase).  We observed a concavity in the abdominal scutes and an apparent male tail.  We assessed #206 as a male spotted turtle.

Spotted Turtle #207 April 2014 and April 2015

We originally observed Spotted Turtle #207 on 6 and & 7 April 2014 swimming in the SouthCoast bog.    We gauged the age of #207 at approximately 9 to 10 years based on annual growth lines and size. We next saw #207 on 11 April 2015.  This turtle grew about 10% in the last year.  As with Spotted Turtle #206, we confirmed #207’s identity by its individualized marginal notches (its number), as well as photographs of its carapacial scute shapes and the positions of its yellow dots. She also had lost her left rear limb below the “knee” joint.

Spotted Turtle #207 Plastron April 2014

Chin and neck of Spotted Turtle #207 were colorful orange with no detectable abdominal cavity.  We assessed #207 as female. The turtle measured 9.11 centimeters straight-line carapace length, 6.90 centimeters maximum width, and 8.17 centimeters plastron length. #207 weighed 114 grams.

Spotted Turtle #207 Plastron April 2015

When we observed #207 on the afternoon of 11 April 2015, chin and neck had turned charcoal black and a slight concavity had appeared in the plastron’s abdominal scutes.  The tail seemed larger and thicker. We assessed #207 with full male characteristics.  He stretched 10.03 centimeters straight-line carapace length, 7.44 centimeters maximum width, and 8.81 centimeters plastron length.  #207 weighed 130 grams (a 14% increase since April 2014).

Spotted Turtle Study Kit

We continue to monitor the delayed emergence of spotted turtles in this SouthCoast bog due to the record smashing winter and the late spring.  Each turtle that we observed last year, our first season at this particular bog, was individually marked, so that we can follow its progress upon recapture.  We will examine recaptured turtles very carefully to determine whether other adult spotted turtles have changed their secondary gender characteristics, especially the signature female spotted turtle orange color of their chins and necks.