By Mike Kaczmarczik, Outreach Coordinator and Teacher Naturalist
Photos by Paul Kaczmarczik
Summer in Philly means it’s time to head down the shore for sun, sand, and surf. What I look forward to the most during any foray to the beach isn’t basking under the sun, but swapping my beach towel for a flashlight once the sun goes down.
A nighttime walk on the beach is like entering an entirely different world. Ghost crabs of all sizes emerge from their burrows and scurry across the sand searching for food. Juvenile dogfish, a small species of shark, cruise the edge of the surf, their eyes glowing in the beam of my flashlight. Wind and waves create a thick layer of background noise, and all you can see is the round patch of sand illuminated by your flashlight.
This year the light emanating from my flashlight fell onto something surprising. In the compact sand left by a receding tide was a set of tracks I had never encountered on the beach. I followed the tracks until they disappeared into the soft sand. A few yards down the shoreline I came across another set of the tracks, this time much fresher, as their creator was still making her way to the dunes.
The maker of this trackway was Malaclemys terrapin terrapin, the northern diamondback terrapin. Diamondbacks are unique among all turtle species for living exclusively in brackish (salty) water in bays and estuaries along coastal regions. No other turtle in the world has adapted to this environment as diamondback terrapins have. True turtles, those with flippers, live in the open ocean. Tortoises are strictly terrestrial. Other turtles (referred to in general as terrapins) live in bodies of freshwater or almost entirely on land.
You don’t often see diamondback terrapins in the ocean except for a brief period in late spring or early summer when females prepare to lay eggs—and that’s why this sighting was so exciting. After 30 years of visiting the Jersey shore, I was witnessing, for the first time, female diamondbacks on their way up the beach to dig nests and lay clutches of eggs in the soft sand by the dunes.
The following night I set out for the beach around midnight. Within minutes I spotted a terrapin floating in a small tidal pool. Every 40 or 50 yards along the beach was another large female looking to do her part in propagating the species.
Terrapin mothers receive a bad rap as being “absentee” parents. It is true that after laying a clutch of eggs, the mother will have completed her duties. But laying that clutch of eggs is no easy task.
The beach is full of dangers for the soon-to-be mother. A family of foxes regularly patrolled the area, and nightly I saw fox tracks on the beach and a few sets of glowing eyes in the dunes. Bits of dried white eggshell served as evidence of nests the foxes had already raided.
Digging a hole in loose sand using only your back feet is a challenge in itself. I watched one determined female scoop and flick away sand for well over an hour. The result? A slight depression in the sand. The mother, unable to make a suitable nest, wandered up into the dunes in search of a better site.
In mid-August each year, the hundreds of baby terrapins emerge from the sand. As the nearly quarter- sized babies make their way toward safety, they will evade foxes, birds, raccoons, and cars. So be alert the next time you are down the shore!
While you’ll probably have to wait until next year to spot terrapins at the beach, you can see some beautiful northern diamondback terrapins in Outside In, our children’s discovery center. Meet our two adult females, Cheerio and Squirtle and our male, Clem. Be sure to check out Clem and Squirtle’s brand- new babies, hatched early in the summer. They will be on display in Outside In until they are old enough to be released into the wild. Purchase tickets today and come see them during All-Star Days, December 27-30.