Reader Tracy O'Lear snapped this photo of a red fox at Corey Creek in Southold in November 2010.

If you’ve got a mangy dog, blame a mangy fox.

North Fork veterinarians are reporting a significant increase in cases of Sarcoptic mange among pet dogs — and that, they say, is directly linked to an abundant fox population. Foxes often carry mange, a skin disease caused by parasitic mites that cause loss of fur and incessant scratching. The mites are easily transferred from foxes to dogs.

In more heavily developed Riverhead, no new mange cases have been reported.

“I haven’t seen it at all in the past two or three years,” said Dr. Mandip Lachhar,” a veterinarian at Riverhead Animal Hospital.

Dr. Beth Dunbar of Mattituck-Laurel Veterinary Hospital said that practice has seen five to 10 cases of mange in the past two months, an unusually high number.

“I’ve personally seen about three cases,” she said. “Last time I saw it before that was in vet school when I was in Indiana.” That was in 2002.

Dr. Robert Pisciotta at North Fork Animal Hospital in Southold said he’s recorded about 10 cases in the past month or so. “It’s usually one to none at this time of year,” he said.

“It can be very stressful for the dogs and also for the owners since the animals can be up all night scratching,” Dr. Pisciotta said.

The disease can be hard to pinpoint. Viewing skin scrape samples through a microscope is the diagnostic norm, but in some cases a dog can have the mites that go unseen.

Drs. Pisciotta and Dunbar both said the increased incidence of the skin disease comes from a jump in the local fox population. Mange is spread mainly by contact with an infected fox or a wild dog.

“But we don’t have too many wild dogs running around out here,” Dr. Dunbar said. Dogs can get mange from direct contact with a fox or from sniffing around areas where a fox has lain, like its den.

“There’s a lot of manage in the fox population out here,” said Dr. Pisciotta. “We had a problem with that on Shelter Island a few years ago.”

Read more about the mange problem in Thursday’s issue of The Suffolk Times.

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