Dog detectives track pesky nutria, pigs; rodent's gone from Delmarva

Federal wildlife services are using man’s best friend in the final stages of eradicating the invasive nutria from Delmarva.

Marnie Pepper is the supervisory wildlife biologist at the Chesapeake Bay Nutria Eradication Project,  part of the United States Department of Agriculture’s Animal and Plant Health Inspection Service. She heads the nutria dog detector program.

“Nutria are large, semi-aquatic rodents, originally from South America,” she said. “They were brought to Maryland’s Eastern Shore for their fur, back in the 1940s.”

At the time, the idea was to farm nutria, but that idea didn’t take. Whether they escaped or were released, they ended up free-roaming across Delmarva.

Before action was taken to eradicate them, they lived everywhere from Blackwater National Wildlife Refuge in Dorchester County, Maryland, to Bombay Hook National Wildlife Refuge in Kent County, to Virginia’s Eastern Shore.

“All the characteristics that made them great for farming also made them a formidable opponent for the ecosystem,” Pepper said.

Nutria have no natural predators, are relatively disease-resistant and, as omnivores, don’t have any special dietary needs. In Delmarva’s wetlands, they thrived.

“Unfortunately, their feeding behavior is very destructive. Because they focus on one area and eat the roots of plants, they basically compromise the structure of the marsh, accelerating erosion,” Pepper said.

Nutria eat nonstop – about 25 percent of their body weight per day. In the Blackwater National Wildlife Refuge, they destroyed about 5,000 acres.

Thanks in part to Pepper and her dogs, the Chesapeake Bay Nutria Eradication Program has been very successful. There hasn’t been a confirmed nutria on Delmarva since May 2015. The last case of infestation was at Mud Mill Pond, in western Kent County.

Pepper and her colleagues first used hunting dogs, trained to sniff out and bay, or howl from a distance, at nutria.

“Dogs are amazingly effective. There were a lot of really cool stories about how everybody was done for the day, the wind shifts and suddenly the dog indicates there’s a nutria only a few yards away,” Pepper said.

Since nutria have now been eradicated, the program has switched to scat-detecting. According to Pepper, dogs with high toy drives make the best detectors.

“Think of a dog that just wants to play fetch ‘til your arm falls off,” she said. “That’s the really cool thing about this program; it’s all a big game for the dogs.”

Some of Pepper’s detector dogs come from shelters and rescues, but often, they come by way of flunking out of other programs. Her first detector dog was supposed to be a diabetic alert dog but proved to have too high an energy level – perfect for nutria detecting.

There are four teams in the program, and right now they’re doing a final once-over of the Delmarva Peninsula. Don’t worry – these dogs are far from retirement.

“The dogs are all cross-trained on feral swine, or wild pigs,” Pepper said. “We don’t have any in Maryland or Delaware, but many neighboring states do they are a huge problem.”

Detector dogs can be trained to detect any number of things, from sea turtle eggs to human disease.

“The dogs have been essential,” Pepper said. “And a side benefit that can’t be overlooked is the effect they have on the employees. Working with a dog helps reinvigorate employees, keeping them focused and enjoying the work they’re doing.”