By Sean Cockerham, McClatchy Washington Bureau (TNS)

WASHINGTON — As the summer tourist season approaches on North Carolina’s Outer Banks, there’s a growing hope among horse advocates that the iconic wild horses of Corolla can be saved from a fate of inbreeding and deformities.

The U.S. Fish and Wildlife Service, which considers the horses “nuisance animals” that compete with federally protected birds for habitat, has loosened its stance and is allowing the introduction of new horses into the threatened herd in order to bring in fresh genes.

“It’s almost too good to be true,” said Karen McCalpin, executive director of the Corolla Wild Horse Fund, which protects the Spanish mustangs.

The horses have survived on a narrow barrier island in the northern edge of North Carolina’s Outer Banks for some 500 years, believed to be descendants of colonial mounts that swam to shore after Spanish galleons ran aground on the shoals and sandbars of the Outer Banks.

They are some of the last remaining wild horses in the Eastern United States and a hugely popular tourist attraction. But the herd of about 100 horses has become severely inbred and is down to a single maternal line, resulting in deformities and fears of extinction.

Representative Walter Jones (R-NC), repeatedly pushed a bill to allow the herd to grow to 130 horses and to let the Corolla Wild Horse Fund bring in horses from a different island at the far southern tip of the Outer Banks in order to infuse fresh genes into the herd. But the Fish and Wildlife Service successfully opposed the bill — some of the horses cross into the Currituck National Wildlife Refuge, and the Fish and Wildlife Service considers them a problem.

Under pressure from horse advocates and members of Congress, though, the Fish and Wildlife Service is now letting outside horses join the Corolla herd under a new management plan for the horses.

“We aren’t objecting to the new horses for genetic diversity, and we are part of the new management plan for the Corolla herd,” said Fish and Wildlife Service spokesman Tom MacKenzie.

The Corolla Wild Horse Fund has taken advantage of the green light by quickly adding a four-year-old stallion, Gus, bringing him to join the herd from Cedar Island, some 100 miles to the south.

“I DNA tested him first to make sure that he was indeed a colonial Spanish mustang…so that is the first introduction of new colonial Spanish banker strain genes into the herd in five centuries,” McCalpin said.

Now McCalpin hopes to add a pair of Cedar Island mares.

“I actually prefer that they use mares. They incorporate into a population easier, a stallion is going to receive a challenge from other stallions and may not succeed in actually getting in and contributing genes,” said Gus Cothran, an expert in equine genetics at Texas A&M University who has studied the herd.

He said the introduction of new horses gives him hope for a herd he identified in 2012 as dangerously inbred.

“The concern is whether it’s too late,” Cothran said. “I don’t think so, but that would be something to think about.”

McCalpin is still pressing for Congress to pass Jones’ bill letting the herd go up to 130 horses. Without it, she fears the Fish and Wildlife Service might decide at any time to limit the herd.

“This has got to be our year because I’m basically just holding the population steady because of birth defects,” she said.

Photo: Corolla Wild Horse Fund via Flickr