In the southeastern U.S., a car trip to the beach often means crossing a bridge that separates the beach from the mainland. Many beaches that people visit in the Southeast are on islands, and between the island and the mainland are vast salt marshes, aromatic tidal creeks, and scenic lagoons and bays. The East Aiken students cross the Intracoastal Waterway and arrive at a barrier island complex near Cape Canaveral, Florida on November 15, 1999. In addition to all the neat wildlife and habitats that are nearby, the area is also home to the Kennedy Space Center.
The Coastal Plain of the Atlantic and Gulf coasts has a very gentle slope. The gentle slope, along with ocean currents, rising sea levels, and prevailing winds combined to form offshore ridges of sand along parts of the coastline. These low, offshore ridges are called "barrier islands." Barrier islands generally run parallel to the shore, and are backed by estuaries and salt-marsh wetlands.
Salt Marsh Habitat
Some of the most beautiful examples of barrier islands on the Atlantic Coast are National Seashores, a part of the National Park system. Assateague National Seashore (VA), Cumberland Island National Seashore (GA), and Canaveral National Seashore (FL) are all located on barrier islands. A visit to any of these jewels is well worth the effort (Canaveral National Seashore, Merritt Island National Wildlife Refuge).
Barrier islands are dynamic and ever-changing places. Tropical hurricanes and winter northeasters, combined with longshore ocean currents, keep the barrier island sands in a constant flux—erosion from some places, redeposition in other places. Land that is there one day is gone the next, and what was water one day may be beach the next. It is rare, and kind of exciting, to be able to see geology in action on such a time scale. (For more on barrier island formation see the Florida Oceanographic Society web site.)
Glass [Legless] Lizards (genus Ophisaurus)
Many barrier islands are substantial chunks of land, much more than a raised sand bar in the shallow water. Some barrier islands are more than 20 miles (32 km) long and over a mile (1.6 km) wide. Larger islands are apt to have numerous habitat types. Between the ocean on one side and the bay on the other, barrier island habitats include the beach, primary dunes, sandy overwash terraces, grasslands, shrub thickets, oak and pine forests, salt marshes, and occasionally fresh water ponds. Many of these habitats are ideal for a sand-loving lizard, the glass lizard.
Four species of glass lizards occur in the southeastern U.S. In locales where two or more species are found, they can be difficult to tell apart. These legless lizards can be distinguished from snakes by their movable eyelids, external ear openings, and (to some extent) movements.