The following article first appeared in Star-News (Wilmington, North Carolina), Dec. 8, 2008, and is reproduced with permission of the author.
"30-Pound Ugly Rat" a Destructive Neighbor
Chuck Carmack can often be found at Airlie Gardens, snapping pictures of just about every critter he sees in the New Hanover County gardens along Bradley Creek.
But this May, he saw a pair of animals in one of the gardens' many ponds that looked a bit strange."I just thought it was an otter or a beaver at first, although they seemed awful big," Carmack said.
Then he got home, opened the picture on his computer and saw the animal's Doritos-colored buck teeth.
"I knew it wasn't something that should be here when I saw that," Carmack said.
What Carmack had captured on film were nutria, semi-aquatic rodents native to South America that are running amok in much of the coastal United States.
"The easiest description of a nutria is a 30-pound ugly rat," said Perry Sumner, a biologist and section chief with the N.C. Wildlife Resources Commission. "And there's nothing redeeming about the nutria being here. They just completely eat the vegetation in an area. They don't stop."
Now, it appears this rat on steroids that's already established in much of eastern North Carolina has set its insatiable appetite and phenomenal breeding ability on the Cape Fear Coast and the region's extensive wetlands - assuming it's not here already.
"If you're anyone who has a focus on estuarine protection, I'd put it one my ‘Ten Most Wanted' list," said Jonathan McKnight, acting wildlife director with the Maryland Department of Natural Resources. "It's the John Dillinger of invasive species.
"It doesn't just change habitat. This sucker eats habitat."
That's because a nutria, whose large head comprises one-third of its body, is a plant-eating machine that doesn't stop when marsh grasses are chewed down to the ground. Like pigs, nutria will dig into the ground to get to the roots of the plant.
But in coastal marshes, the roots are what hold the porous marsh soils in place. Without the root system, marshes become easily susceptible to washing away with the tide.
"The nutria would simply add insult to injury," said Andy Wood, education director for Audubon North Carolina, noting that the area's marshes are already under siege from sea-level rise and human-induced impacts.
In Louisiana, where millions of nutria live after their ancestors escaped - or were released - from fur farms before World War II, nutria in the 1990s were blamed for damaging 100,000 acres of tidal marshes at any one time.
So Louisiana decided to act, launching a bounty program paying trappers $5 per nutria tail. The state famous for its chefs and Cajun cooking also tried to develop a market for nutria meat, with less success.
Edmond Mouton, a biologist with the Louisiana Department of Wildlife and Fisheries, said trappers have caught an average of 300,000 nutria in recent years and reduced the amount of affected wetlands to an estimated 23,000 acres at any one time.
Maryland has taken a more forceful approach since nutria started damaging wetlands on the state's Eastern Shore.
Instead of a control program, the state has embarked on an eradication campaign, which appears to be making some headway.
"We're trying to save the Chesapeake Bay," McKnight said. "We can't do that if we lose our wetlands."
But eradicating the nocturnal rodent can be hard, primarily because of their phenomenal breeding capacity.
Sumner said they will breed twice a year, any time of year, with litters that average five babies. In as little as four months, those young are capable of reproducing on their own.
Even Louisiana's alligator-filled bayous can't control a population that grows that quickly, since it takes at least a 5-foot gator to take down one of the large rodents, Mouton said.
"And even a gator can only eat so many nutria," he added.
In North Carolina, nutria were first reported in the wild in 1941 after they escaped from a fur farm on Cape Hatteras.
For years, they didn't expand much beyond the Outer Banks and Currituck Sound.
But Sumner said several decades of mild winters allowed them to expand south and west, with the big rodent now on the outskirts of Raleigh.
While it's possible a few have skirted down the coast toward Wilmington, and have been spotted at Airlie prior to this year, Sumner said their likely path toward Southeastern North Carolina has been via the Cape Fear River.
And it appears they are getting closer to establishing a permanent presence near the Port City.
Bob Roush was paddling Shelter Creek in Pender County with some friends last month when he saw an animal, which looked too large to be a muskrat, swimming in the water.
He later came across a nutria carcass along the road. Audubon's Wood also is pretty sure he saw a dead nutria along U.S. 17 near Porters Neck two weeks ago.
David Webster, a biologist at the University of North Carolina Wilmington, said there have been spotty sightings of nutria along the Northeast Cape Fear River for at least 15 years.
So far, there are no reports of them establishing a permanent presence in our area.
"But when they do establish a foothold here, and they will, we can expect to see their numbers increase significantly," Webster said. "It's just a matter of time."