♫ Narrator: Their home is a narrow ribbon of sand... shaped by wind and wave. Assateague Island, where plants and animals follow the rhythms of tide and season. Bound to this untamed land, horses have adapted... living free... returning back to the wild. Assateague Island is a 37-mile-long barrier island along the coast of Maryland and Virginia. It's the eastern edge of the North American continent where land gives way to the Atlantic Ocean. Constantly changing, the island supports an intricate web of life: rich... vibrant... resilient. At the water line and on the beach animals blend into their sandy home. Behind the dunes, plants shelter from the ocean spray while trees twist and bend under the stress of salt and wind. Along the Bayside, mosquitoes and dragonflies have specially adapted to live in and around saltwater. Many of these plants are finely tuned to their barrier island habitats and live nowhere else. But if an animal can survive on Assateague, it may thrive... and no animal embodies this more clearly than the island's wild horses. The horse's story on Assateague begins more than 300 years ago. Mainland colonists put horses to pasture on the island in order to avoid livestock taxes. The island served as a natural corral. Left alone, their survival depended on instinctive behaviors. Over time, memories of the horses' origins faded. Emerging again is a new, colorful story. Local folklore described how a Spanish ship wrecked off the coast and horses swam ashore. Genetic studies reveal a more complex ancestry- the result of continuing introductions of new horses over the centuries. More than 300 years later, Assateague's wild horses are flourishing. ♫ Today, they live in two distinct and separate herds. In Virginia, the southern herd consists of roughly 150 horses. They graze leased areas in the Chincoteague National Wildlife Refuge, and their lives are closely linked to local traditions. They belong to the Chincoteague volunteer fire company. ♫ Every July since the 1920s, volunteers known as Saltwater Cowboys round them up. They herd the horses along the beach then swim them across the bay to Chincoteague. There, the volunteer fire company auctions the foals to raise money. To the north, in Maryland, another herd roams. Their lives are very different. Carl Zimmerman: The National Park Service horses, as best as we can, are managed as wildlife. That's a hands-off approach. No supplemental feeding. No veterinarian care, in general. They're pretty much on their own to live or die as wildlife. Narrator: Wild and untamed, the horses have become as rugged as their home. Their short legs and stocky build are perfectly suited to the landscape. Sand and marsh pose no obstacle for these sure-footed horses. ♫ They've adapted to the challenging conditions of every season. When the weather turns cold, they grow thick winter coats. Throughout the year, they graze mostly on coarse grasses. Their diet also includes twigs, phragmites, and even an unlikely delicacy- poison ivy. Because most of their food is coated with salt, they drink twice as much freshwater as domesticated horses. They find it in the island's ponds and shallow rainwater pools. All of the salt and water combine to give the horses a bloated appearance. Wild horses have adapted so well to Assateague, they can alter the island itself. Carl Zimmerman: As a non-native species, on Assateague, the horses can have a pretty dramatic effect on virtually the entire ecosystem of Assateague Island, ranging from individual plants, plant communities, other organisms dependent upon those plant communities, right up to the physical processes that shape Assateague Island. Narrator: From beach to bay, horses can have an impact on all of Assateague's habitats. Carl Zimmerman: The horses' effects on the salt marsh are particularly evident. In a normal, healthy marsh, you would expect to see grasses up to your knees. In a lot of areas on Assateague, it's down around your ankles or it looks more like a golf course than it does a healthy salt marsh. In addition to the effects on the plants themselves, that grazing has also displaced other organisms from the salt marsh, things like fiddler crabs... secretive marsh birds... Those creatures have been displaced because of the effects of the horses on that salt marsh habitat. ♫ Narrator: American beach grass is another favorite of the horses. When they over-graze, they can damage a key part of the island. Beach grass roots act like small anchors holding dunes in place. Without beach grass, dunes can blow away. And with weakened dunes, the island becomes more vulnerable to erosion. To preserve a balance between wild horses in Maryland and barrier island habitats, scientists and the National Park Service have developed an innovative program to maintain 80 to 100 horses. It's a safe, non-hormonal vaccine that prevents pregnancy in mares without altering their natural behavior. A vaccine-filled dart is fired from a rifle. The vaccine is delivered to the horses without a human ever handling them so they don't become habituated to people. Dr. Jay Kirkpatrick has led this groundbreaking program for over 20 years. Alison Turner: Yeah, that's her. Jay Kirkpatrick: So step one, is you find the mare... Okay, she's the one we want. ... and then you mix your vaccine. [clicking] You have to actually mix this vaccine right on the spot. ♫ [rifle mechanism clicks] Step two is you've got to get within shooting distance of the mare and that can take a long time. That's probably the most frustrating part of the whole set of steps. Narrator: Many horses recognize the National Park Service uniform and personnel. They've learned how close the ranger needs to get... and stay just out of range. ♫ Jay Kirkpatrick: Then, step three is taking the shot. We dart the horse only in the rump, a lot of muscle. [rifle shot] Narrator: The dart startles more than it stings. Jay Kirkpatrick: And step four is recovering the dart. You want to test to make sure that that dart has fired. Narrator: Each dart delivers a year's dose of vaccine. Jay Kirkpatrick: And the fifth and final step is to take a little piece of grass or weed and to run it down the needle of the dart. That tells you whether it fired. When it hits the plunger and you know it's fired, it just is a feeling like nothing else I know. Particularly if it's been a tough horse. [rifle shot, hoofs galloping] And you're filled with elation for 15 minutes until you realize you've got to go get another horse now and start the process all over again. Narrator: The National Park Service vaccinates mares at two, three, and four years old. And then they are allowed to foal. After a mare gives birth to one foal, she may be vaccinated annually. [rifle click] Assateague's program has been such a success, several other wildlife management organizations have modeled their own programs after it. Jay Kirkpatrick: I really had no idea whether we could make this work when we started and it's been spectacular, actually. Narrator: Because mares give birth just once, and only in their prime years, they lead longer and healthier lives. And since almost every mare foals, there's a healthy mix to the gene pool. Every spring, a few new foals arrive, maintaining a stable population. Wobbly at first, foals can walk within an hour or two of birth. A young foal sticks close to its mother, spending most of its days nursing or napping. ♫ As they grow stronger, they venture a little farther, though still sleeping for hours each day. Visitors often think that when a horse is lying down, it must be sick. But even adult horses lie on their sides for short periods of deep sleep. Some like to doze with their legs tucked beneath them. This is perfectly natural behavior. More commonly, all horses catch short naps standing up. This is what grabbing a few quick winks looks like for a horse: One hind leg cocked, neck lowered, and ears flopped to the side. On their own, horses exhibit natural behavior. But in an unnatural setting, their behavior can be altered in ways that pose a threat to both animals and humans. When horses learn that people might feed them, they hang around roads. As a result, drivers have unintentionally hit and killed many horses. Others have been injured but survived. One of the surest ways to put a horse in jeopardy is to offer it food. The potential harm from close contact isn't one-sided either. When people get too close to wild horses, they get hurt. Man: Brian, don't go behind the horse. Never walk behind a horse. Narrator: A bite can wound and a kick can do even more damage. Several times a year, visitors suffer serious injuries because they got too close. ♫ These are large, powerful, and unpredictable animals. Not domesticated horses, and definitely not pets. And that's exactly what we value most about them- their wildness. If they become habituated to people, they'll lose the independence and self-reliance that make them so special. Assateague Island is one of the few places where we can still see horses as wild animals. Left to themselves, they've returned to ancient behaviors. They form bands in which each animal has its own rank and role. The typical social group, called a harem band, includes a mature stallion, his mares, and their young. It's a clear hierarchy with the lead mare determining where and when the group moves, eats, and drinks. Horses within a band groom each other to strengthen social bonds. Nibbling and touching seem to help bind the group together and calm them down. The stallion's primary role is to guard his band. [horses neighing] When another stallion gets too close, he may try herding the mares away. If the challenger keeps up his pursuit, a confrontation begins with posturing and displays. When neither stallion backs down, a fierce battle of kicks and bites follows. ♫ Almost all stallions bear battle scars. A young male learns by play-fighting, honing life skills he'll need later. When he begins to show interest in the mares, the lead stallion will drive him from the group. The young stallion then wanders alone or joins a small temporary bachelor band. Young females usually leave their family band on their own, which helps avoid inbreeding. They'll join an established harem band or pair up with a single, lucky bachelor. Together, they'll form the core of a completely new band. ♫ Each band has a home range. They spend most of their days grazing in the marshes and open areas on the bayside. Cattle egrets often hitch a ride on their backs. From this vantage point, the bird can spot insects stirred up as the horses graze. Mosquitoes are irritating and biting flies can draw blood. Horses deal with these bites and itches in a variety of ways... A quick scratch helps. And anything solid becomes a rubbing post. But nothing's better than a good old-fashioned roll. ♫ During the hot and humid summer, when swarms of biting flies become too much to bear, wild horses seek refuge on the beach. The breeze and salt spray cool them off and keep flies away. Unafraid and curious, Assateague's horses view the beach as their own. The best approach is to give them their space. ♫ Humans have been associated with horses for thousands of years. It is only natural that we are drawn to them. On Assateague Island, wild horses rekindle something deep within us, something timeless and meaningful to our lives- strength and grace... raw power and beauty... These extraordinary creatures, connected so intimately with one another and to their natural environment... They bring us back to a place we, perhaps, had forgotten... back to the wild. ♫ ♫ ♫
