Essie, a Chincoteague pony with 'swamp cancer,' died Tuesday, officials said.
Seven ponies had the disease, which is not a true cancer but rather a disease that comes from the oomycete Pythium, which is similar to a fungus. The affected ponies, including Essie, underwent surgery, but Essie ultimately did not survive.
Denise Bowden, spokesperson for the Chincoteague Volunteer Fire Company, wrote in a Facebook post that the other ponies appear to be doing well. The ponies are maintained by the fire company, which hosts the famous swim and auction each summer.
Swamp cancer has historically proven very difficult for veterinarians to treat, although those in Chincoteague are working with experts from around the country to decide on the best treatment for the ponies.
Officials are now working with the United States Fish and Wildlife Service to bring in biologists to test soil, water and plant samples to try to contain the disease.
Not much is known about the disease, but what is known is that it comes from Pythium insidiosum, which typically lives in plants that grow near water. When those plants are wet or are submerged in water, they release zoospores, which are effectively spores that can swim, into the water.
Those zoospores can spread infection by getting into holes on an animal's body as small as a mosquito bite or a scrape. The disease has a low infection rate, experts say, but it can be very difficult to get rid of once it gets into a creature's body. Ponies regularly live to be 30 or older, but Essie was just 5 when she died.
According to the Chincoteague Pony Pedigree database, which tracks the ponies, Essie was a buyback pony, which means after she was purchased at auction, and the winner of the auction donated her so she could live out her life on the island.
The database also notes that Essie was a chestnut tobiano pony. Her markings included blaze, a wide white stripe down her face, and four socks, meaning each of her legs had white markings that extend approximately halfway to her hock (the equivalent to a human ankle).
Essie's progeny are The Heroic One from Southern Assateague and Wendy’s Carolina Girl. She had 36 siblings, according to the database.
Two ponies died from swamp cancer last year, but Essie is the first pony known to have died of the disease this year.
While those close to the ponies were sad to lose Essie, they were also able to celebrate a new pony on the island.
The new pony is a male medicine hat, meaning the horse is primarily white with a "hat," or a colored patch on its head that looks similar to the human article of clothing. Not much else is known about the baby pony other than that it has blue eyes, which makes it especially prized in some circles.
In some cultures, medicine hat horses are considered to bring good luck. As some commenters point out on the Facebook post announcing Essie's death and the new pony, good luck might be just what the Chincoteague ponies need.
