Assateague Island National Seashore

Wild Horses
The majestic and wild horses of Assateague

Two herds of wild horses known as "ponies" by an adoring public make their homes on Assateague Island. The herds are separated by a fence at the boundary between Maryland and Virginia. In Maryland, horses are often seen around roads and campgrounds. In Virginia, look for them in Black Duck Marsh from observation platforms along Beach Road and Woodland Trail. The Maryland herd is managed by the National Park Service. The Virginia herd is owned by the Chincoteague Volunteer Fire Company and allowed by permit to graze on Chincoteague refuge. Each year horses from the Virginia herd are rounded up and many of the foals are sold at the Pony Penning and auction held on the last Wednesday and Thursday of July. Proceeds from the auction help support the fire company.

Today's wild horses on Assateague Island are descended from domesticated stock that was grazed on the island as early as the 17th century by Eastern Shore planters. The planters grazed their horses here to avoid mainland taxes and fencing requirements. Only slightly smaller than many other horses, these shaggy, sturdy animals are well adapted to their harsh seashore environment. Marsh and dune grasses supply the bulk of their food; they obtain water from freshwater impoundments or natural ponds. Their social organization, behavior, and communication habits are explained in publications available at visitor centers. Although domestic in their distant origins, these horses are wild today. Respect them as such and view them only from a safe distance. While usually appearing docile, they are prone to unpredictable behavior and can inflict serious wounds both by kicking and by biting. Do not tease or pet the horses.

"Are they truly wild?"
Since they take care of themselves in all seasons without help from people, the horses are considered wild animals. The term "feral" is also applied to the horses, meaning they are descendants of domestic animals that have reverted to a wild state.

"Then are they dangerous?"
Any wild animal can be dangerous and the ponies are no exception. They appear tame and gentle but may become aggressive very quickly. Each year several visitors are bitten or kicked by "tame" horses. Feeding the horses and any other wildlife is unhealthy for the animals, dangerous for the visitors, and strictly prohibited. Some wild horses become "beggars" with prolonged feeding and at least one each year is killed by a car while seeking a handout. Enjoy the horses from a distance.

"How many horses are there?"
The wild horses are split into two main herds, one on the Virginia end and one on the Maryland end of Assateague. The herds are separated by a fence at the Virginia-Maryland state line and the population size of each herd is kept below 150 animals to lessen their impact on island ecology. These herds have divided themselves into bands of two to ten animals and each band occupies a home range.

"Where can I see them?"
In Virginia, look in the fenced marshes south of the Beach Road and from the observation platform on the Woodland Trail. They are usually seen on the "Wildlife Tour." In Maryland, the wild horses are more free to roam and may be anywhere. Drive slowly along island roads (but keep moving!) and park only in designated areas. Also look in the parking lots, at Old Ferry Landing, and near the beach in summer. In other seasons, look in the salt marsh.

"What do the wild horses eat and drink?" Almost 80 percent of their diet is coarse saltmarsh cordgrass and American beachgrass, supplemented by thorny greenbrier stems, bayberry twigs, rose hips, seaweeds, and even delectable poison ivy! Because they eat so much salty food, the horses drink twice as much fresh water (from natural ponds) as do domestic horses and may also drink some salt water; this gives them a "fat" appearance. Although this seems like a meager subsistence, the horses of Assateague have adapted well to an island diet and do not need "help" from people. In fact, such help in the form of "good" food can be detrimental to their digestive system and overall health.

"Where did they come from?"
The origin of wild horses ("ponies") on Assateague is a story shrouded in mystery with few facts available. Colorful tales of horses struggling ashore from a shipwrecked Spanish galleon remain part of local folklore but have not been accepted by many historians. However, research shows that as early as the 17th century, barrier islands were used to graze horses, cattle, sheep, and goats. This began when colonial legislators passed laws requiring the fencing and taxing of all mainland livestock, as free-roaming animals were causing crop damage. To avoid the cost of building fences, the early settlers used Assateague Island as a natural "corral," fenced in by water. The present-day ponies are most likely descended from these small domestic horses.

"What happens during pony penning?"
The internationally famous events of Pony Penning began in some form during the 17th century when unclaimed horses were captured and marked by colonists in the presence of neighbors on a day of fellowship and festivity. The modern Pony Penning began in 1924 as an effort to raise money for the Chincoteague Volunteer Fire Company and is still held on the last Wednesday and Thursday of July. The Virginia herd, rounded up by the Chincoteague "cowboys," swims across the channel to Chincoteague on Wednesday before thousands of cheering spectators. Most of the foals and yearlings are auctioned off on Thursday and the remaining ponies swim back to Assateague on the following days. New owners must be able to provide safe, humane transportation for their purchases. Most foals are easily tamed and adapt well to domestic life.

"How do wild horses interact with each other?"
Each band or "harem" is made up of a harem stallion, his mares, and their offspring. The size of each individual band is determined by the stallion's ability to hold his mares together. Spectacular displays of rearing, biting, and kicking occur when stallions "battle" over mares. Once dominance is established, the stallion controls his band with a variety of body postures and verbal signals. Young males are forced out of the band by the stallion before they become a threat to him. They wander around the island and form bachelor herds with other males. Young females sometimes leave their harems and wander until they find an established band to join or begin a new band with a bachelor male. This helps to maintain a healthy population and prevents inbreeding.

"How do ponies interact with other animals?"
Having no natural predators or competition for food, the ponies live in relative harmony with deer, fox, raccoons, and other Assateague wildlife. The only animal to truly interact with the ponies is the cattle egret. This white, long-legged member of the heron family assists the ponies in their never-ending battle against biting flies and ticks by eating these pests off their coats and around their legs. In return, the ponies flush out more hidden insects than the egrets could find on their own. In summer, it is quite common to spot a cattle egret perched on a pony's back for an hour or more.

"What about mosquitoes?"
Luckily, the thick-skinned ponies (unlike people) are not irritated much by Assateague's healthy mosquito population, although a few have contracted equine encephalitis and have died from this disease. Far more annoying are three varieties of biting flies. When the insects become too ferocious, the ponies rub themselves on vegetation, roll in the sand, or swish their tails in each other's faces. Often in desperation, ponies will wade into the bay or stand in the surf and let waves crash on their backs to get some temporary relief.

"How do ponies survive extreme weather?"
Centuries of adaptation have enabled the ponies to survive the rigors of island life in all seasons. Thick, furry coats and a hardy nature serve the ponies well during Assateague's damp, chilly winters. In extreme cold or storms, the ponies will seek shelter in wooded areas and become browsers, eating more shrub material and less grass. However, it is not winter, but the hot, humid, insect-ridden summer that severely tests the ponies' ability to survive. In fact, an island existence proved to be too harsh for 40 western mustangs brought in to improve the breeding stock of the Virginia herd in the late 1970's—most of them died the first year.

Is research being done on the wild horses?"
Knowledge of pony behavior and its impact on visitor safety and the island ecology is essential for the managing agencies. A wealth of information is being provided by researchers in a continuation of studies that began in 1975. Through this work, important questions regarding population size, ecological balance, and pony/visitor interactions have been answered. Careful study has shown that the Maryland herd should be limited to between 120 and 150 animals, since uncontrolled population growth would have a damaging impact on island ecology.

"How is the population controlled?"
In Virginia, population growth is controlled by the annual auction. To control the Maryland population, researchers have developed a unique non-hormone, anti-fertility vaccine that temporarily prevents pregnancy in selected mares. Instead of using hormones to prevent ovulation or fertilization, the mare's own immune system prevents fertilization after forming a "glue" around her egg as a reaction to pig ova protein! Administered as a serum in a dart gun, the completely reversible process is unique in that it does not harm the ponies, nor does it alter their behavior in any way. The success of this revolutionary wild horse "birth control" is having a great impact in the field of mammalian wildlife and zoo management.

While action may be taken to end the suffering of a gravely ill, seriously injured, or dying pony, no extraordinary measures are taken to prolong life. As with other species of Assateague wildlife, ponies that are sick or weak do not survive—only healthy animals produce offspring, thereby maintaining a strong, vital population. With careful management, this unique resource will continue to thrive on Assateague and provide enjoyment to thousands of nature enthusiasts, photographers, and people who just love horses.

Published: 29 Apr 2002 | Last Updated: 15 Sep 2010
Details mentioned in this article were accurate at the time of publication



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