The ornate box turtle gets its name by being an introvert: the small reptile can completely close its shell, hiding away in a self-made box. But it’s not just their tendency to retreat into their own shells that has made the turtles hard to find. The prairie-dwelling species is experiencing a worrying decline. This spring, conservation researchers in Iowa, where the ornate box turtle is considered threatened, received a helping paw from four dogs specially trained to sniff out the highly camouflaged species.

Meet Rooster, Jenny Wren, Jaybird and Mink, the canine counterparts of John Rucker, a retired schoolteacher from Montana. As NPR’s Kate Payne reports, these turtle-finders are Boykin spaniels—a dog once bred to hunt waterfowl and wild turkey in South Carolina.

Dick Hakes of the Iowa City Press-Citizen reports that Rucker stumbled upon the turtle-tracking business accidentally; he was trying to train his dogs to find birds when one of them started bringing back turtles, gently gripping them in its mouth. Rucker used the turtles’ scent to train his other dogs, and now travels the country in a van with his band of Boykins to help researchers in need. And the spaniels are good at their jobs: In 2010, scouting out turtles in Illinois over 10 days, they outpaced human volunteers, retrieving 85 turtles to the humans’ 12.

Rucker’s “super dogs,” as he calls them, recently pitched in to find turtles in Iowa, where conservationists are anxious to assess the population so they can better manage the creature’s habitat. “The turtles are very camouflaged and not easy to find,” Jason Taylor, property stewardship specialist for Iowa’s Bur Oak Land Trust, tells Hakes. So it was helpful to have the dogs join the search on lands owned by the Trust. Once they got their command from Rucker—“Find turtle”—Rooster, Jenny Wren, Jaybird and Mink set off on their reptile-sniffing mission.

“[A]s they strike a scent trail their tails will start wagging furiously, and then their whole demeanor becomes extremely excitable,” Rucker tells Payne of NPR.

When the dogs found a turtle, they brought it unharmed to researchers from Cornell College, who would then weigh it, measure it and photograph the unique markings on the underside of its shell, which helps conservationists identify and track individuals in a given population.

Habitat destruction threatens the ornate box turtle’s survival in Iowa. The animals make their homes in the sandy prairies, where the turtles like to burrow. But as Taylor tells Hakes, “[o]ne of the problems is that sandy prairie is also a good place to build a house.”

While it is illegal to remove the threatened turtles from the wild in Iowa, people continue to take them to sell as pets. And the animals’ numbers are so low that the removal of just one female could spell the end of a given area’s entire population, Taylor says in an interview with Shannon Moudy of Fox28.

NPR’s Payne reports that Rucker’s dogs were able to locate 137 turtles over just three days in the field. Each reptile the dogs find, Rucker tells Moudy, is important to the effort to save them. “They’re part of the richness of the wilderness,” he says, “and we want them to stay here.”