Assateague slows pony contraception for 2017
Word of new foals may be on the way, as the Maryland side of Assateague Island will not be administering its pony birth control regiment in 2017.
The purpose behind the decision is to keep the herd balance in a target range of 80-100, said Liz Davis, education coordinator for Assateague Island.
"The goal is to see an increase in foaling by minimizing contraception, and monitor and adjust over the years to stay within the 80 to 100 goal," Davis said.
Davis stressed that the 2017 plan is not an outright suspension of the birth control program, but rather a slow reduction of the birth control regiment that has taken place over the past six years. The plan is also based on the age of the herd.
"The Maryland herd of wild horses currently contains a large proportion of mares aged 20 to 33," Davis said. "These older mares are unlikely to foal again, so in order to refresh the reproductive population in the near future, an increase in foaling among the younger mares needs to occur."
Davis said that, to promote foaling, contraception is only given to 2-year-old mares. While mares are able to conceive at this point of their life, they generally aren't mature enough to support the foal.
READ MORE: Foal born into Assateague Island pony herd
READ MORE: Assateague Island pony dies in vehicle collision
Since 1988, the Maryland side of Assateague Island has controlled the population of the ponies by way of a dart gun vaccination containing a non-hormone treatment, known as PZP, that blocks fertilization. This practice is a non-invasive and virtually harmless way to control the population, according to the National Park Service.
This method, which is hinged on preserving the horses as wild animals, differs starkly from the Chincoteague method of control, which utilizes a privately owned herd regularly reproducing, and then auctioning off the foals to benefit the Chincoteague Volunteer Fire Company.
But controlling the size of the herd isn't only beneficial to the horses, keeping the pony population balanced is crucial for the entirety of Assateague's ecosystem, according to Assateague Coastkeeper Kathy Phillips.
"The ponies have such an intrinsic value to the island, but keeping that population in check benefits all of Assateague's inhabitants," Phillips said.
Phillips also lauded the birth control program as an effective means for making sure the population doesn't dwindle, while at the same time preventing it from growing out of control, likening it to a deer hunting season.
"I think the program has been working very well in keeping that population in check," Phillips said. "It stops the herd from growing to a size where they're grazing out of control, but at the same time allows for new foals to be born."
Phillips said that controlling the numbers of foals benefits everyone; from the herd, to tourist revenue on the Island.
"We know that the ponies are really one of the biggest attractions here, and we definitely want to see them healthy and controlled," Phillips said.
In 2016, the count of the Assateague herd stands at 88, consisting of 66 mares and 22 stallions. As Davis said, many of the herd are aging, meaning foaling is crucial for keeping the population stable.
According to a post on the Assateague Island Facebook page, the park has sent off samples of manure collected from mares to the Science and Conservation Center in Montana, where a test for changes in hormone levels indicative of pregnancy are carried out. Results of the tests, and news of potential new foals on the way, will come in January.
"When new foals are born, that of course brings in more people," Phillips said. "When the herd is healthy, it's good for everyone; from us to the tourists, to all of other flora and fauna living on the Island."