Don Lewis Examines Male Spotted Turtle at SouthCoast Rookery

Close by the SouthCoast rookery with its assortment of great blue heron and osprey treetop aeries, the Turtle Journal team monitors a spotted turtle mating aggregation that occupies a small portion of an NSTAR power-line right-of-way.  Over the past couple of years NSTAR has brought in heavy machinery in, so far, failed attempts to fill in these wetlands and probable vernal pools.  Last year the ground was torn up by tracked vehicles that gouged through the swampy terrain.

Male Spotted Turtle #222 (Clemmys guttata)

On Monday, April 7th, the Turtle Journal team observed Spotted Turtle #222 basking in this mating aggregation.  A mature male, #222 weighed 138 grams (4.9 ounces) and his shell measured 9.72 centimeters (3.8 inches).  He is a recapture at this site from the time before NSTAR tried to fill in these wetlands.  So, at least for the nonce, it appears that this mating aggregation continues despite human efforts to degrade the natural habitat.

Vive La Difference!

(Telling He from She)

Male Spotted Turtle #222 Plastron (Bottom Shell)

Female Spotted Turtle #105 Plastron (Bottom Shell)

Telling the difference between males and females proves an extremely useful research skill.  Spotted turtles exhibit gender dichromatism.  Females, such as #105 immediately above, have brightly colored chins; males, like #222, have drably colored chins.  Females have thin, dainty tails and males have thick, showy tails.  Females also have flat, washboard abs, and males have an indentation in their abdominal plastron (bottom shell) scutes.  Although some might suggest that the following distinction is subjective, females are exquisitely beautiful and males are merely strikingly handsome.  Now you, too, can celebrate “la difference.”

 Gorgeous 4-Year-Old Female Spotted Turtle (Clemmys guttata)

Springtime on the SouthCoast yields discoveries and adventures for the Turtle Journal team.  The weekend treated us with spotted turtles at a number of SouthCoast sites, including this magnificent young female spotted turtle that weighed 2 1/4 ounces and measured less than 3 inches long.

SouthCoast Grassi Bog (Former Cranberry Bog)

On Sunday, April 6th, we ventured to the Grassi Bog on the SouthCoast to search for spotted turtles and a potential mating aggregation.  We observed a few painted and spotted turtles basking on inaccessible grass hummocks in the flooded pond.  We walked around the edge of the bog, searching for spotteds, and we heard the telltale “plop” of a turtle plunging off a basking perch.  We just caught glimpse of a spotted shell submerging into the murky ooze.

Female Spotted Turtle Hiding in Plain Sight

While on land spotted turtles seem bright and gaudy, their color, shape and pattern blend perfectly into the background of a swampy bog.  In other words, they disappear while hiding in plain sight.  The photograph above illustrates the challenge we face in finding spotted turtles as they bask in indirect sunlight six to eight inches below the surface of the pond.  Remember:  You have the advantage of knowing that there is a spotted turtle in this picture.  Researchers are scouring acres and acres of swampy bogs at a fast pace trying to find them.

Sue Wieber Nourse Examines 3 Female Spotted Turtles

Fortunately, Sue Wieber Nourse is an expert turtle researcher, and she discovered three female spotted turtles basking and hiding beneath the surface of the swamp.  Sue perilously plunged into the flooded bog and immediately sank hip deep as she snagged the unsuspecting turtles.  These specimens ranged in age from four to ten years old, in weight from 2 1/4 to 4 ounces and in shell size from 2.8 to 3.6 inches.

~ 4-Year-Old Female Spotted Turtle from Grassi Bog

The little one was adorable.  Her brightly colored neck spotlighted her gender since spotted turtles exhibit sexual dichromatism.  Males have drably colored grayish necks.

Three Female Spotted Turtles from Grassi Bog

All three ladies were processed, marked for future identification and released back into the wild at the same location where Sue had captured them.  When we returned to Grassi Bog on Monday, we found the elder female in roughly the same spot, and captured a 5.5 ounce male nearby.  This area of Grassi Bog seems optimal for a spotted turtle mating aggregation.