Authorities in Virginia say one of its wild ponies on Chincoteague Island has died of a disease known as "swamp cancer" that has affected several others as well.
News outlets cite a Tuesday release from the Chincoteague Volunteer Fire Company announcing that a horse named Essie died after surgery, after her infection was "too far gone." Spokesman Denise Bowden reported that other ponies who had the surgery seem to be doing well.
"Swamp cancer" isn't cancer, but rather is pythiosis, which is caused by an organism similar to a fungus.
Two ponies died from it last year. Essie is the first pony to die of the disease this year.
Members of the fire company met with the United States Fish and Wildlife Service this week to try to figure out the cause of the problem.
"Over time, they will be collecting soil, water and plant samples to see if we can get this mess contained. There has just got to be a solution!!" the fire company, which cares for the ponies, said in a Facebook posted.
The Chincoteague Pony Pedigree database says Essie was born in 2013 and bred by the fire company.
Bowden did note some good news: the herd welcomed a foal. "He is gorgeous!!" the firefighters said.