Barrier Island Ecology
Barrier islands as protection
Hunting Island is one of the six Beaufort Barrier Islands that include Harbor, Hunting, Fripp, Pritchard’s, Capers, and Old Island. These barrier islands protect the inland areas and help create the fertile salt marshes that surround the islands. These islands were used by Native Americans for centuries as hunting and gathering places. The Port Royal Sound area was chosen by early European explorers and settlers because it is so well protected from the sea by the extensive barrier islands. Although settlements from the 16th century are largely gone, Beaufort has many very old houses, some over 300 years old. This is only possible because the barrier islands protect the inland areas by absorbing and dissipating energy from hurricanes, storms, winds, and waves.
Barrier islands stretch south from mid-New York all the way to Texas and Mexico. This part of the North American coastline is the longest and most varied barrier island coast in the world. Scholars have estimated that in protection from hurricanes in the US, barrier islands have provided $9,683 per hectare (approximately 2.5 acres) per year in damage protection. As hurricane severity and frequency increase with climate change, that value is expected to become $11,223.
In addition, barrier islands provide the protection needed for the creation of productive salt marshes. These marshes are tidal—experiencing high and low tides like the ocean. At high tide, a wide variety of sea creatures live in the nutrient “soup” of the salt marsh that is based on the decomposition of the grasses. These include dolphins, tiger sharks, mullets, shrimp, and crabs. Ospreys soar above hunting these sea creatures. At low tide wading birds like egrets, ibises, and herons are seen fishing here. Raccoons may pad through the pluff (or plough) mud to dine on shrimp or crab.
Barrier islands also protect inland waters for sailors. The Intracoastal Waterway is a 3000-mile sea route along the Atlantic and Gulf coasts that takes advantage of barrier islands to provide protected water for boaters. Coasts without barrier islands are much more dangerous, especially for small sailing vessels, because they must sail in the unprotected open seas. The prefix “intra” means within, because the Intracoastal Waterway is within the coasts.
In most places, natural bodies of water make up the Waterway, and in other places canals or passages were dredged to accommodate marine traffic. The Intracoastal Waterway passes well to the west of Hunting Island traveling south through St. Helena Sound to Coosaw River and past Beaufort to the Port Royal Sound. Then it stays landward of Hilton Head and Daufuskie Island and on toward Savannah.
Photo courtesy of
Claire Mueller/Coastal Expeditions
Photo courtesy of
Coastal Expeditions
Photo courtesy of
John Alexander