Shifting Sands: A Natural History of Assateague Island

A salt marsh remains a unique place in a world where unique species and habitats are disappearing right before our very eyes. Assateague Island and neighboring Chincoteague Island are one of the few places in the world where visitors can find a thriving population of feral ponies – once domesticated animals that have reverted to a wild state. How these wild ponies ended up on the shores of Maryland and Virginia is still up for debate. One explanation perpetuated by local folklore claims that the first generation of ponies on the island were survivors of a Spanish shipwreck off the coast. Regardless of their origins, these ponies have adapted to the harsh, dynamic conditions of a salt marsh environment.

The text-book definition of a salt marsh is an estuarine wetland dominated by salt-tolerant grasses, but beyond this lies much more. Salt marshes are incredibly important ecosystems, which provide a buffer to protect the coast against storms, help to dilute and remove pollutants from the environment, and provide wildlife habitats that protect a plethora of young marine species. As if those aren’t impressive enough undertakings for an ecosystem, salt marshes also provide important services to humans like providing food, transportation routes, and recreational areas.

But salt marshes all over the country are in peril. Over 50 percent of our wetlands have been filled in and eliminated altogether. They are perceived as wastelands with the potential to be full of pests that carry dangerous diseases. So I have set out to explore one of the more famous salt marshes on the east coast of the United States in an attempt to garner attention and perhaps provide education on the importance of these ecosystems. Built by sand that persistent waves have dredged from the ocean's floor, the island is constantly being reshaped and moved by ocean waves and wind. Because of these natural (and some unnatural) forces of change, Assateague Island is one of the world's most dynamic places.

An Experiential Love Affair

Crossing the Verrazano Bridge, which spans Sinepuxent Bay to connect main land to the barrier island, I enter into a world where human domination of the landscape is no longer so overwhelming. Italian explorer Giovanni da Verrazano visited the island in 1524 while searching for a shortcut passage to China. He affectionately christened the seashore “Acadia” because of the impressive beauty of the trees. Although there is some disagreement about its origins, it is likely that "Acadia" is derived from the ancient Greek word “Arcadia” which since classical antiquity has been used to describe an earthly paradise.  And even if the great trees have long since been felled in the wake of colonial settlement of this area, the wetlands here still are vibrant with life, providing a sanctuary for diverse living kinds. 

My fondness for this island began many years ago. Every summer my parents would make the three-hour trek from our home in western Maryland to Assateague with me and my two younger brothers in tow.  Once there we would we would spend a week disconnecting from the everyday concerns of urban existence and reconnecting with each other. Some of my favorite childhood memories took place there on the beaches and forested trails. I can wholeheartedly say that my affection for the environment started right there on that island. 

And that affection continues to this very day. Assateague Island is the place where I recently saw my first green heron, stoically poised in a small tidal pool on the bay side of the island. While watching this impressive creature, I realized what a treasure it is to live so nearby a place with such incredibly vibrant biodiversity. One of the most important lessons I’ve taken from my expeditions into these wetlands is the need for intentional mindfulness if one is going to encounter a world filled with living kinds beyond my own kind. I can be described as a fidgety person with a mind more often than not flitting from thought to thought aimlessly. But a whole other way of being conscious is an attentiveness that stays open and alive to its surroundings, emerges in my trips to these wetlands. As a result, I have slowly become a more competent observer of the natural world.

According to Thomas Lowe Fleischner mindfulness “involves cultivating a state of increased clarity and intensity of consciousness, one that filters out illusions and projections.” This practice is essential when attempting to forge connections between the human and non-human world. In a world filled with so many distractions, losing sight of what is actually lying before me becomes all too easy. A better understanding of symbiotic processes learned through the technique of attentive observation leads to an increased appreciation for all members of the biotic community, which ultimately could lead to more adequate awareness of environmental issues and increased protection. I’ve learned a lot about salt marsh ecosystems throughout this observation process, but for everything I’ve learned, I realize there is much more that I and all the rest of humanity doesn’t know. Each observation brings with it new questions.

Specialization of Salt Marsh Living

Salt marshes used to be considered wastelands with no economic potential; just an area between two habitats, the land and the sea. Nothing useful here, it would seem. But this is precisely what makes salt marshes so valuable. As I walk along the edge of the tidal pool where land meets sea, I become entranced in my thoughts regarding the diversity of life that occurs in eco-tone areas, just like this one. According to Judith Weis and Carol Butler, authors of Salt Marshes, an eco-tone is a transition area between two biomes where species communities meet and integrate. Eco-tone areas are especially important because the health and well-being of one community often times relies on the health of the neighboring community. It is unlikely that one could survive without the other.

Driving a few miles past the state park entrance, I find myself in the portion of Assateague Island that is a national park. The majority of the island is owned and protected by the federal government, with the state of Maryland responsible for the remainder.  This area receives so much attention because of its natural beauty, it historical relevance and its scientific importance.  Most crucial are the possibilities offered here for land and wildlife preservation.  And for me, this place is where I come here to spend time reflecting and observing the natural world, particularly a small tidal pool lying between the Atlantic Ocean and Sinepuxent Bay that is home to a variety of Assateague’s unique flora and fauna.

The plant and animal species that call this sandy island home are tough and tolerant. They have specialized adaptations which help them to survive under inhospitable conditions. They live in a place where even the most intrusive of species, humans, cannot live because of the lack of solid, stable ground. Despite these conditions, it is a very popular recreation spot for surfers, beach goers, dog owners, fishermen, campers, and many others. The collision of these two worlds is an interesting study in the relationship between nature and man. The grasses and plants on the island are extraordinarily well adapted to living in waters and soil ladened with salt. They also provide a habitat for shore birds, small crabs, fish, and many other intertidal species. Salt marsh cordgrass (Spartina alterniflora) is one of the more common grasses on Assateague. It is also a preferred food choice for the islands resident feral horses, as well as safe haven for a number of young animals. If marshes are considered the nurseries of the sea, than cordgrass would be their nurturing guardian. Aside from protecting tiny critters, the trees, shrubbery, and grasses play a vital role in protecting the island against erosion and severe storms. In addition to the salt marsh cordgrass, American beach grass and sea rocket can be commonly found on Assateague Island. Common trees and shrubs on the island include wax myrtles, loblolly pines, marsh elder, red maples, sweetgum, persimmon, sassafras, several oak species, and American holly.

“Shrub communities on Assateague establish themselves on or behind dunes, in protected depressions, and along the edges of marshes, with characteristic species growing in each location depending on the levels of salinity and moisture present.” (www.nps.org). But the harsh natural setting isn’t the only environmental catalyst for adaptation. These species also have to fight for survival against the disastrous effects of climate change. Salt marshes are the lowest possible areas of land before submergence and they are the first to be impacted by violent storms driven by climate change. As the ocean warms, the volume and the height of the ocean increases due to thermal expansion and melting ice. According to the National Park Service “Climate scientists predict that the oceans around the mid-Atlantic coast will rise one meter (3 feet) by year 2100. A rise of one meter will have a dramatic effect on our coastlines. A one meter increase will flood many of the world’s largest cities and result in the loss of two-thirds of the coastal wetlands in the United States.” (www.nps.org). If that’s not scary enough to elicit more protection for salt marshes, maybe a more human-centered reason will; a loss in salt marshes in this region would not only be detrimental for the species that make their home there, it would also cause a loss in the local economy. A large number of fish species and shellfish depend on salt marshes for food and shelter. As salt marshes diminish, so do the populations of these species and so will the jobs and industry that rely on their sustained continuance.

Over several months of visits to my tidal pool, I have encountered an impressive array of avian species: the great blue herons standing majestically in the tall grasses, the double-crested cormorants stretching their large black wings in the sunshine, the song birds that flutter from tree to tree plucking berries and singing their own personal tunes. Herons, I have discovered, love this area for several reasons. One has to do with an easily harvested and plentiful food source. The tidal pool fills and drains (not completely but the change in depth is noticeable) in synchronicity with high and low tide. Whatever small fish, frogs, crabs, and other small ocean critters get caught in the pool as the tide moves out are fair game for the hungry herons. I have also learned the great blue heron (Ardea herodias) is the largest of all North American herons with long legs, a twisting neck, and a think dagger-like bill that they use with lightning-fast accuracy when hunting in shallow waters. When hunting, the great blue heron will often times wade slowly or even stand perfectly still in order to stalk fish and other small prey in shallow water or even open fields before they thrust their long necks forward as they stab their prey with that long, sharp bill.

Migratory birds are also attracted to the island, as opposed to say neighboring Ocean City, for some good reasons; diminishing wetlands has led to significant protection efforts on the island creating an almost human-free  area for their migration. Assateague also provides a good quality habitat because of these protection efforts; a perfect blend of moderate weather, reasonable food security, and shelter. Assateague Island officials released this statement regarding migrating ducks – “The U.S. Fish & Wildlife Service recently released a preliminary fall flight index survey of 90 million ducks. Data gathered from extensive air and ground survey's is critical to the management and conservation of Assateague waterfowl populations. Throughout the years wetland habitats have diminished and with these limited resources, a tremendous value has been placed on protected areas such as Assateague Island.”

In addition to the impressive plant life and bird species on the island, it is also home to a unique species of deer. The sika deer (Cervus nippon) was introduced on the island in the mid 1920’s. They are originally from Japan and live naturally in parts of Korea, Siberia, China, Vietnam, and Taiwan. Sika deer are smaller than white-tailed deer and are said to exhibit elk-like behavior. On Assateague Island, sikas can be found in the loblolly forest area, sand dune areas, and along the marshes. They eat leaves from myrtle bushes, grasses, persimmons, shrubs, and even poison ivy.

Each of Assateague’s unique species have adapted evolutionarily different than their land dominant counterparts because of distinct environmental conditions like salt laden vegetation, lack of fresh water, and a constantly shifting environment. Our understanding of the vast ecological importance of Assateague Island continues to expand as each complex layer of existence unfolds and presents itself, just waiting for someone with the right degree of intentional attentiveness to take notice.

 -  Ashley Crane

Works Cited:

"Assateague Island National Seashore Visitor Services." Assateague Island National Seashore Visitor Services. N.p., n.d. Web. 02 Dec

. 2014.

"Assateague State Park." Assateague State Park. N.p., n.d. Web. 02 Dec. 2014.

Fleischner, Thomas Lowe. The Way of Natural History. San Antonio: Trinity UP, 2011. Print.

United States. National Park Service. "Assateague Island National Seashore (U.S. National Park Service)." National Parks Service. U.S. Department of the Interior, 02 Dec. 2014. Web. 02 Dec. 2014.

Weis, Judith S., and Carol A. Butler. Salt Marshes: A Natural and Unnatural History. New Brunswick, NJ: Rutgers UP, 2009. Print.

Abstract:

Built by sand that persistent waves have dredged from the ocean's floor, Assateague Island is constantly being reshaped and moved by ocean waves and wind.  The plant and animal species that call this sandy island home are tough and tolerant. They have specialized adaptations which help them to survive under inhospitable conditions. They live in a place where even the most intrusive of species, humans, cannot live. Because of these natural (and some unnatural) forces of change, this island is one of the world's most dynamic places.