Tracking Down Species Identification

By Caitlin Calabrese

   It’s summertime in Brevard County which means sea turtle nesting season is in full swing.  Three of the seven world sea turtle species regularly use Brevard beaches for their annual nesting: the loggerhead, green, and leatherback turtles. Luckily for turtle biologists and nesting surveyors, each species of turtle has unique tracks due to their unique morphology, enabling a swift species identification process for each nest. Brevard beachgoers and turtle enthusiasts also can learn the ropes of tracking down the species of turtle that correlates to each nest.

        

   On Brevard beaches between late April and mid-August, you are most likely to encounter loggerhead tracks, as Brevard County is the leading nesting site for loggerheads worldwide.  Loggerhead tracks will appear as staggered, comma-shaped indentations. The staggered nature is due to an alternating gait, rather than a simultaneous, parallel push of both hind flippers. In fact, with loggerhead turtles, hind flipper marks are seen nearly exclusively, as their short front flipper marks are covered by their longer hind flippers. Looking at the center of the track, a tail drag will not be visible due to the short nature of a female loggerhead tail. A nose push, however, is sometimes obvious, as female loggerheads push their cumbersome heads up the sand. 

   From mid-June to mid-September, you might also see tracks from a green sea turtle. Although not as populous as the loggerheads, green turtles are endemic nesters to Brevard County. Green tracks will vary greatly compared to tracks of the loggerhead. Greens are larger turtles, and green tracks will be larger than loggerhead tracks by an average margin of 25 centimeters, or 10 inches.  Green turtles also have a different gait, employing parallel flipper pushes rather than alternating.  Another contrast is that green sea turtles have longer front flippers than loggerheads, and a sharp dash is seen on the lateral most point of the track indicating significant front flipper depressions.  The hind flipper tracks will appear medially to the front flipper “dashes” as parallel ridges. In addition, green sea turtles have considerably long tails, and a tail drag can be seen down the center of the track. The tail drag will be straight, but with small “V”-shaped marks visible indicating where the turtle paused to rest during her taxing journey across the sand.

   The early birds of the Brevard sea turtles are the leatherback turtles that begin nesting in early March and conclude in late July. A premier distinguishing factor of a leatherback track is its sheer size. These gargantuan girls leave tracks ranging from an average of five to seven feet in width. Like the green turtle, the gait of the leatherback is a parallel flipper placement, but her front flippers will leave two indentations in her lateral “dashes” making the front flipper dashes a significant portion of the entire track. The hind flippers will leave parallel tracks medially to the front flipper marks, and a sizeable tail drag will be obvious down the centerline. Leatherback turtles also like to take advantage of the beach and move in a more curved or swirled pattern. 

   This is an exciting time to be down on Brevard beaches in the presence of one of nature’s most impressive and elusive phenomena. While honing your species track identification skills, we do kindly remind you to avoid stepping on or walking through turtle tracks, as tracks provide significant and usable data to nesting surveyors. In addition, always approach sea turtle tracks carefully and beginning at the water line; a female turtle may still be nesting in daylight, and it is imperative that we humans do not spook them from this critical and laborious process. 

References:

Witherington, B., Witherington, D. (2015). Our Sea Turtles: a practical guide for the Atlantic and Gulf, from Canada to Mexico. Pineapple Press, Inc.: Sarasota, Florida.