Though the turtles, which can be held in the palm of the hand, are usually found in small pockets throughout the area, a significant colony of 30 lives near a stream on a 300-acre dairy farm in Salem County. Under the federal program, new measures are being taken to help this population flourish.
On a recent crisp morning, 40 cows on that farm unwittingly participated by mowing down and munching on red maple saplings, sedges, ferns, and tangled weeds that might deprive the turtles of the sunshine they need for basking and warming their bodies. Keeping the vegetation in check also allows the turtle eggs to get the sun they need to incubate, according to Bill Pitts, a DEP zoologist who keeps an eye on the Salem turtles.
In March, the farmer had received a $4,000 federal grant to erect fences and gates to manage the cows' grazing habits to meet the turtles' needs. For six months each year, the cows will freely roam in the wetlands portion of the pasture, and in the remaining months, they will be funneled to another field.
Though the turtles need sun, they also need vegetation for their nests and for foraging during the nesting and breeding season in the spring, Pitts said. The fence strategy also allows the turtles to move about during that season without the risk of being stepped on.
"It's a recovery plan," said Pitts, who visits periodically, marking the turtles to maintain a count and to chart their health. "The ultimate goal is to remove them from the list of endangered species" the way the American bald eagle was delisted when it began to thrive on its own.
To find the black-shelled, roughly four-inch-long critters, Pitts hunts among the sedges or pokes a stick repeatedly into the muck to see whether he hits something hard. He requested the farm's exact location be withheld to prevent possible poaching of the rare creatures.
The greatest threats to the turtles are development, invasive and native over-growth of plants in their habitat, and illegal trade and collecting, according to a website of the U.S. Department of Agriculture, which provides funding for the program. The USDA could not be reached for comment because of the federal government shutdown.
The website said two-thirds of the lands occupied by endangered species are privately owned. By cooperating with the landowners, the website says, the survival rates of these turtles can be improved. Sheep and goat farmers also participate.
Because the turtles are so reclusive, hiding in the muck during much of their lives, it is difficult to estimate the total population. But the DEP has counted and marked roughly 1,000 statewide since 1974, Pitts said. Other states, he said, have far fewer, and the numbers are declining.
The turtles, known by the distinctive orange patches on the sides of their heads, live mostly in wetlands. To survive, they require a "mosaic of habitats" with spring-fed streams, muck, and some dry land for breeding and nesting cycles, Pitts said. "They don't travel far - they're homebodies," he said.
Smaller pockets of the critters have been identified in Burlington and Gloucester Counties, Pitts said.
But the Salem colony is "a showcase project," according to Zarate. "Turtle-wise, 30 is a fairly good number."
At some other non-dairy farms, Zarate said, the DEP is recommending the landowners introduce grazing animals to help the bog turtles thrive. When there are no cows to control vegetation, the DEP sometimes has to cut down trees or do controlled burns to removed unwanted overgrowth.
Pitts said sometimes other measures must be taken to keep predators - foxes, raccoons, and hawks - from stealing the bog turtles' eggs. The nests are covered with wire mesh.
Farmers who don't participate in the program still must avoid jeopardizing the survival of the bog turtles. The DEP has the authority to file complaints against any landowners who violate endangered-species laws.
Last year, a Burlington County flower farmer was fined for chopping down a row of trees and blocking up a stream, which led to the deaths of bog turtles that lost their critical water source. The DEP said the farmer had been warned against clearing land so close to the turtle habitat.
Developers also must do environmental assessments to check for bog turtles and other endangered species before they can proceed with a project. If turtles are found, the developers must take measures to protect their habitat and include a 350-foot buffer.
"We really need to give these turtles the habitat they need to persist," Pitts said. "They are a species whose numbers are dropping precipitously."
Where found: From Massachusetts to Georgia
Habitat: Forested wetlands, marshes
Size: 3-4 inches
Color: black shells, orange patches on its head
Lifespan: 40-50 years
Eggs: 3-5 in a clutch
Food: Snails, slugs, invertebrates, insects, vegetation
Habits: Hiding in the mud
Scientific Name: Glyptemys muhlenbergii