Hatteras Island: The Point
Hatteras Island is easy to miss when looking at a map. It’s off the coast of North Carolina, and incredibly small; you have to zoom in quite close just to see it. Hatteras Island is a barrier island, formed by the deposition of sand transported by wind and ocean currents over time.
Barrier islands play a big role in protecting the land behind them. This is where the term “barrier” comes from. They absorb the wave energy from the ocean and give rise to many important ecosystems; behind most barrier islands you’ll find marshes, swamps, and brackish water ecosystems.
Hatteras Island, however, is a special barrier island. Not only does it protect the coast of North Carolina, but it influences ecosystems across the northern East Coast and the rest of the globe. Hatteras is uniquely positioned geographically. It protrudes out into the Atlantic Ocean, getting in the way of the northbound Gulf Stream.
As a result, Hatteras deflects the Gulf Stream out into the Atlantic, away from the coastline of the northern half of the east coast. This allows the Labrador current to extend down from Greenland to Hatteras. The Gulf Stream is roughly 5-8 times faster than the Labrador current. Without Hatteras, the Gulf Stream would push the Labrador back, allowing the warmer equatorial water to extend further north.
Deflecting the Gulf Stream also protects ecosystems to the north of Hatteras from invasive species that are wreaking havoc on the southern coastal states. Plants/animals can invade a new region in multiple ways: naturally or as a result of human transportation.
Many small invertebrates hitch a ride on the bottoms of boats, or in the ballast water of large shipping vessels. These little guys are hard to prevent and spread pretty easily. Larger vertebrates, however, are a little easier to manage and can be physically filtered/removed from ballast water. As a result, they rely more on invasion by natural means: moving to a new region on their own.
Lionfish have become more and more of a nuisance in the waters around Florida and the Gulf of Mexico. They make great invaders, having virtually no predators and able to survive in a wide range of conditions. Lionfish have not been able to claim a stake in fragile ecosystems like the Chesapeake Bay, partly thanks to Hatteras. The ones who do attempt to make the commute along the Gulf Stream find themselves flung out into the middle of the Atlantic, unable to make the journey around the point of Hatteras and up the East Coast.
Coastal towns rely on the critters that live in the marine ecosystems to stimulate their economies. An invasion by lionfish could spell disaster for these communities. Hatteras Island makes it all possible.
Environmental stewardship and protection of natural coastal ecosystems are vital to many communities and industries across the world. Hatteras is a prime example of how one little pile of sand props up the economies and livelihoods of people along the entire East Coast of the United States.
