Turtle-sniffing dogs searching Long Island woods to protect species

April set off down a wooded path on the North Fork, nose to the ground, darting and weaving through the bunchberry, blackberry and ferns. She wore a bright orange vest treated with permethrin to deter ticks, a chest protector to prevent cuts from brambles and a GPS collar. She had been in training for more than a year, and now this was her first real job as a wildlife detection dog.

Her task was to pick up the scent of Eastern box turtles, whose numbers are dwindling across their home range, from Maine to Texas.

Last year Anna Thonis, a postdoctoral researcher at New York University, launched a study of Long Island’s Eastern box turtles, a "species of special concern" in New York — not officially threatened or endangered but imperiled by habitat loss and fragmentation, the illegal pet trade, pesticides and cars.

"We don't know right now exactly what's going on with these guys," Thonis said as she followed April into the woods last month. "But we'll collect some data, and hopefully we can use that to inform legislation or more action for turtles."

Her research plan called for counting turtles in several locations, from Brooklyn to the East End, to assess the health of each local population. But box turtles are difficult to spot among the dried leaves and low-growing plants on the forest floor. Dogs, with their exceptional olfactory capabilities, can be trained to sniff them out.

Wildlife detection dogs have helped conservationists track dozens of species on every continent but Antarctica. Mixed-breed rescues have found endangered San Joaquin kit foxes in central California and the scat of grizzlies and wolves in Yellowstone. Dogs have discovered trafficked pangolins, tropical parrots and monkeys as well as rhino horns, elephant tusks and bushmeat, helping to shut down poaching operations.

Thonis’s Eastern box turtle study is the first formal study on Long Island to enlist detection dogs, according to Mike Bottini, a wildlife biologist at Seatuck Environmental Association, which is among the groups supporting the research.

Zigzagging, sniffing, moving on, sniffing

April, a Labrador retriever just 16 months old, can pick up the scent of a turtle from 100 yards away in an open field, according to her trainer, Kris Hoffmann. And she has learned to distinguish between her target species and more common ones like painted or snapping turtles, which she will simply ignore.

But because of her youth and inexperience, for this survey, April was supposed to serve as understudy to her more senior colleague, Newton (who goes by Newt), who has been tracking turtles for half a decade in six states, from Vermont to Florida.

Newt appeared to embrace the assignment when he was let off the leash at about 8 a.m. But Hoffmann, who is a wildlife biologist as well as handler, treat purveyor and ball thrower for the dogs, soon noticed he was unusually distracted.

April has not yet been spayed, and she was just coming out of heat, Hoffmann explained. Newt seemed more focused on her alluring scent than on the scents he was meant to follow. So April took his place, zigzagging, sniffing, moving on, sniffing. 

The first box turtle of the day was found not by April but by a sharp-eyed human volunteer. In her field notebook, Thonis recorded the coordinates where the turtle, a female, was found. She weighed her and measured the carapace with a caliper. She noted the turtle’s age by counting the growth ridges on her shell, which look something like the elevation lines on a topographical map, each ridge marking a year.

Next Thonis, who had painted her nails to mimic the patterns on a box turtle shell, wanted to clip the turtle’s nail, for a DNA analysis, a clue to the genetic diversity of the local population. But the turtle had retreated into her shell, her small feet tucked out of reach. "She’s being a little shy," Thonis said. She began gently swaying the animal from side to side, which seemed to coax them out.

After a few minutes of swaying, the turtle unboxed herself. Thonis clipped a toenail and took a blood sample from a foreleg with a syringe. She then made three small notches in the shell, which serve as a distinctive ID, and returned her to the spot where she was found.

All this data will help Thonis understand where these elusive reptiles are thriving or languishing and what hazards they face. On Long Island, she is finding that good turtle habitat is often bisected by roads — an obvious hazard for a small, slow-moving creature. Thonis and her partners hope her research will help identify good locations for wildlife tunnels, like the one recently built in Middle Village, to help turtles and other animals cross safely.

The count for the day on the North Fork: seven turtles, each one logged in the notebook. That may not sound like a lot, but finding those means there are undoubtedly more. "Seven turtles is a very encouraging sign," Thonis said.

The dogs' record for this project: Newt found 14 turtles in a day on the South Fork. As for April, "we expect her to be unstoppable by next year," Hoffmann said.

Thonis plans to return to the same survey spots for many more years. Especially for a long-lived species like box turtles — they can live past 80 — it takes time to determine if a population is increasing or declining, she said.

And long-term studies are critical if ecologists hope to improve their chances of survival.

"In conversations with many long-time Long Island residents, it has become clear that box turtles are far less common than they once were," Thonis wrote in an email. Without consistent monitoring, "we will be much less prepared to understand the causes of any future declines or to develop strategies that could help stabilize and potentially reverse them."

After these box turtle surveys wrap, April and Newton have several more assignments, and then they will return with Hoffmann to their home in upstate St. Lawrence County, where they will spend their days like ordinary dogs — hiking, playing fetch and napping on the sofa, perhaps dreaming of turtles.