Information found on this site: http://www.georgiaencyclopedia.org/nge/Article.jsp?id=h-2777

Barrier Islands

The modern (Holocene) Georgia coast is bordered by a series of relatively short, wide barrier islands separated by relatively deep tidal inlets, or sounds. Extensive sand shoal systems are present seaward of the inlets and central portions of the island.

Eight major islands and island groups comprise the 100 miles of coast between the Savannah and St. Marys rivers. These are Cumberland/Little Cumberland, Jekyll, St. Simons/Sea Island/Little St. Simons, Sapelo/Blackbeard, St. Catherines, Ossabaw, Wassaw, and Tybee/Little Tybee. Tybee, St. Simons/Sea Island, and Jekyll are accessible by roadway and are the only developed barrier islands.

Popularly known as the Golden Isles, the barrier islands are composed of dune and beach ridge sands formed by the interaction of wind, waves, currents, sand supply, and a slowly rising or stable sea level. The availability of sand largely determines whether the shoreline will erode or build. In addition to providing natural habitat for numerous plant and animal communities, as well as recreational destinations for nearby human populations, the barrier islands protect the mainland from the brunt of major storms and hurricanes. The developed barrier islands have no such outer defense.

Six of the eight largest islands are composite barriers consisting of a core of beach and dune deposits formed during the previous, and slightly higher, worldwide sea level of the Pleistocene Silver Bluff, approximately 40,000 to 50,000 years ago. Most of the islands are closely fronted by similar deposits formed during the present, or Holocene, sea-level rise that began 15,000 years ago. At that time the shoreline was located along the edge of the continental shelf some seventy-five miles east of Brunswick, and the exposed sea bottom became an extension of the Coastal Plain with forests, plants, and animals. As the sea level began to slowly rise, animal communities were able to retreat from the rising sea, but forestlands were inundated.

About 5,000 years ago, the rate of sea-level rise decreased from three feet per century to a little less than a foot per century. The Holocene barrier islands began to form at, or near, their present locations and, in most cases, welded onto the Pleistocene barriers. Only vestiges of the Holocene barriers remain on Cumberland, Jekyll, and St. Catherines islands, the major portions having been eroded away by the slow but inexorable rise of the sea.

Coastal Processes

With the exception of wave action associated with seasonal storms (nor'easters) and infrequent hurricanes, the tide's twice-daily ebb and flow is by far the dominant physical process along the Georgia coast. Because of the concave shape of the shoreline and a broad, shallow continental shelf, wave energy is low with wave heights averaging from two to less than four feet at the breaking point.

Prevailing onshore winds are from the northeast and southeast, whereas prevailing offshore winds are from the northwest and southwest. On the eastern coast of the United States, the prevailing alongshore current and sediment transport is from north to south. However, summer wind conditions frequently cause a south to north nearshore sediment transport. (It should be noted that current direction relates to destination, while wind direction relates to origin.)

The average tidal range is just higher than six feet. Seasonal spring (biweekly) tides range up to ten feet and are the highest along the U.S. South Atlantic coast. The geological development of the Georgia coast is profoundly influenced by the large, but cyclic, storage capacity of the tidal marshlands behind the barrier islands. Powered by the six- to ten-foot tides, nearshore waters are forced in and flushed out of the sounds through the constricted inlets between the barrier islands.

The flooding tide brings sediments into the back barrier areas, causing a slow but widely distributed buildup of the tidal marshlands. Conversely, the sudden loss of carrying capacity upon entering the open ocean causes the ebbing tidal currents to deposit the coarsest sediments just seaward of the inlet, thus forming an arcuate, or bowlike, pattern of shoals, which are collectively called an ebb-tide delta. Seasonal wave action modifies shoal and shoreline morphology and, together with prevailing currents, determines the direction and extent of sediment transport.

Ebb-tide deltas, inlets, and relatively short, wide barrier islands are associated with tide-dominant, low-wave-energy coasts. Flood-tide deltas, which form in the interior of the inlets, together with long, narrow barriers that have few inlets, are associated with wave-dominant, low-tidal-range coasts, such as those along Texas and North Carolina.

The coastal sand-sharing system consists of the ebb-tide delta; the alongshore, downcurrent drift of sediment; and the adjacent dynamic beach and dune system. Under natural conditions, the ebb-tide delta is slowly skewed downcurrent, and its southern component welds onto and nourishes the northern, or upcurrent, portion of the adjacent barrier island. Thus the inlet/alongshore drift system passes, or shares, sand from upcurrent sources to downcurrent recipients. Any interruption of this flow of sand, including inlet dredging, jetties, shoreline armoring, and so on, results in the starvation and erosion of downcurrent shorelines.

Tidal Marshlands

Georgia tidal marshlands include the saltwater Spartina sp. wetlands, which are
predominant in the two- to five-mile-wide areas between the barrier islands and the mainland, and the brackish to freshwater wetlands, which extend inland along the estuaries for an additional ten miles or so.

Salt marsh vegetation consists chiefly of smooth cordgrass (Spartina alterniflora) in the widespread low marsh areas. The lower marshes are fringed by the needlerush (Juncus roemarianus), spike grass or saltgrass (Distichlis spicata), and glasswort (Salicornia  spp.) in the higher marshland adjacent to marsh islands (hammocks) and the mainland.

The present marshlands developed over the past several thousand years, as the Holocene sea slowly rose to reoccupy the area behind the existing Pleistocene Silver Bluff barriers and the newly forming Holocene barriers. Marshland sediments consist primarily of river- and tide-borne sands, silts, and clays, in addition to a significant quantity of organic material contributed by indigenous plants and animals. The value of the tidal marshlands as a natural resource worthy of legal protection was recognized by the Georgia General Assembly's passage of the 1970 Coastal Marshlands Protection Act.

Scattered throughout the tidal marshlands are numerous erosional remnants of Pleistocene and Holocene barrier islands and back barrier deposits. These are the vegetated hammocks, or back barrier islands, that because of increasing development pressure and the desire for overmarsh access have been the subject of recent study by the Georgia Department of Natural Resources Coastal Marsh Hammocks Advisory Council. According to the March 2002 council report, 1,200 hammocks, ranging in size from less than one acre to more than 1,000 acres, are located in the six shoreline counties.

History of Shoreline Change

Studies of the historical changes in the mean high-water shoreline of Georgia indicate that the basic causes of shoreline erosion are:

—The worldwide rise in sea level (an average of one to two feet per century);

—Seasonal storms and hurricanes. The Georgia coast has not had a major hurricane (defined as at least a category 3 hurricane) since the late 1890s;

—Man's activities, including channel dredging with offshore disposal of dredged material, jetty construction, shoreline structures, and damming of rivers.

For the most part, the greatest shoreline change occurs along the northern (erosion) and southern (accretion) thirds of the islands. Although most island shorelines show only slight net retreat, large oscillations (several hundred feet or more) have occurred in the past. During the past seventy-seven years, the greatest net shoreline retreats have occurred on Tybee, St. Catherines, Wolf, and Jekyll islands.

The long-term trend of worldwide sea level rise dictates that shoreline erosion will increase. Where shorelines of the developed islands have been fixed by the emplacement of man-made structures, beach slopes have been flattened so that the time the beach can be used between high tides is greatly shortened. In order to have and retain a recreational beach, sand must be brought in from a nearby source. Such beach "nourishment" is costly and repetitious and often has negative environmental aspects.

Future Management of Georgia Coast

With the exception of Tybee, St. Simons/Sea Island, and Jekyll, the remaining Georgia barrier islands are undeveloped as a result of historical and current ownership, distance from the mainland, and, until recently, a relatively low mainland population density. However, along with the current population growth, there is increasing pressure from both the public and private sectors for more visitation to, and entrepreneurship on, state and federally managed islands. This condition is even more critical on the heavily populated coasts along the eastern seaboard of the United States.

A 2003 Pew Oceans Commission Report states that more than half of the U.S. population resides in coastal counties comprising only 17 percent of the nation's land area. This has resulted in a coastal population density almost five times the national average. According to a 2002 Pew Oceans Commission report, the national coastal population will increase 20 percent by 2015, amounting to a daily increase of 3,600 people.

Following the national trend, Georgia's coastal population grew by about 30,000, or about 5.5 percent, between 1998 and 2002. During this same period the state population as a whole increased by an estimated 696,774 people, mostly in the Atlanta region. More specifically, the population growth in the eleven counties of the Georgia coastal zone between 1970 and 2000 was 210,505, an average growth of 16 percent per decade. Thus the coastal marshlands and estuaries are being affected by products and activities of the local population, as well as by those of a much larger portion of the state by way of the five major watersheds that empty into coastal estuaries.

Although the Satilla and St. Marys rivers contribute products derived only from the Coastal Plain, the Savannah, Ogeechee, and Altamaha watersheds extend into the Piedmont and beyond. The headwaters of the Savannah River are in North Carolina, for example, and the drainage basin of the Altamaha River begins in metro Atlanta. The divide between the aforementioned rivers, which flow into the Atlantic Ocean, and the Chattahoochee and Flint rivers, which flow into the Gulf of Mexico, begins in the vicinity of Peachtree Street.

In addition to an expanding resident population, the growing tourism industry creates am impact on coastal ecosystems. The National Oceanic and Atmospheric Administration estimates that coastal tourism and recreation account for 85 percent of all U.S. tourism revenues.

To effectively deal with population impacts as well as those caused by natural processes, decision makers and state management agencies must understand the processes, dynamic nature, and value of the Georgia coast.

Information from this site:  http://www.gpc.edu/~pgore/geology/historical_lab/sedenvirons.htm

2. Beaches and barrier islands are shoreline deposits exposed to wave energy and dominated by sand with a marine fauna. Barrier islands are separated from the mainland by a lagoon. They are commonly associated with tidal flat deposits.

Dunes and beach at Tybee Island, Georgia

3. Lagoons are bodies of water on the landward side of barrier islands. They are protected from the pounding of the ocean waves by the barrier islands, and contain finer sediment than the beaches (usually silt and mud). Lagoons are also present behind reefs, or in the center of atolls.

4. Tidal flats border lagoons. They are periodically flooded and drained by tides (usually twice each day). Tidal flats are areas of low relief, cut by meandering tidal channels. Laminated or rippled clay, silt, and fine sand (either terrigenous or carbonate) may be deposited. Intense burrowing is common. Stromatolites may be present if conditions are appropriate.

Information from this site: http://www.knowtheconnection.com/pdf/CC%20GA%20barrier%20islands.pdf

Information from this site: http://www.tybeeisland.com/history.shtml

Information from this site:  http://www.sherpaguides.com/georgia/coast/northern_coast/tybee_island.html

Sherpa Guides > Georgia Coast & Okefenokee> Northern Coast > Tybee Island

Tybee Island

[Fig. 10] Tybee Island, the most densely developed barrier island on the Georgia coast, consequently lacks most of the natural communities found on Georgia's other barrier islands because of past use and poorly planned development. Here you have renourished beach on the eastern side, dunes with sea oats and pioneer plants at the northern and middle beach areas, and salt marsh on the Back River.

That's not to say Tybee Island doesn't have its own unique appeal. The island is a good place to stay to walk the beach, bird watch, go fishing, ride a bike, and take easy day trips to nearby attractions, including the city of Savannah. Tybee is also loaded with fascinating characters, excellent fishing, gorgeous views, and cold mixed drinks. If Ernest Hemingway were alive today, he might be living and writing books on Tybee.

One reason Tybee Island is significant is that it is one of only four of Georgia's 15 major barrier islands that can reached by car, which has been true since 1923. DOT plans call for making four lanes of US 80, the transportation artery linking Tybee and Savannah, which means even more cars, visitors, and development are in the future of this small island.

Tybee is Georgia's northernmost and 11^th-largest barrier island, measuring approximately 2.5 miles long by 0.75 mile wide. The Holocene island consists of 3,100 acres, of which 1,500 acres are uplands. Nearly 3.5 miles of beach runs roughly north and south before curving toward Savannah at the north end, where it reaches the Savannah River. Across the river and Tybee Roads (the busy shipping mouth of the river) lies South Carolina and Daufuskie and Hilton Head islands. Tybee Island has a permanent resident population of 3,000, which swells on summer weekends to 30,000.

Early in Georgia's history, Tybee Island was recognized as a strategic piece of land to protect the port of Savannah. At different periods of Georgia and U.S. history, lighthouses were erected on the northern end to guide ships and coastal forts were built and manned to protect the coast (see Tybee Lighthouse, and Fort Screven). The last lighthouse is still in use, and the last military installation called Fort Screven—an active base from 1(912) 897 to 1945—is now a national historic district, with some of the fort's emplacements and structures used as homes, garages, apartments, and a museum.

It is hard to walk far on Tybee Island without making a friend of a local, who will regale you with what I call "True Tybee Tales." Some locals relish calling their town the "Redneck Riviera" or "Truckstop by the Sea," but Tybee's local color is actually more diverse than these monikers suggest. Very rich and very poor families, surfers and soldiers, old timers and babies, straights and gays, Yankees and rednecks, environmentalists and litterbugs, blacks and whites, the beautiful and not-so-beautiful, all democratically share Tybee's beaches in close quarters without seeming to notice one another. You quickly realize that you are not strolling the exclusive beach at Sea Island. This is not to say that there's perfect harmony among the locals. Islanders pack the seats at city council meetings, which are considered "must-see" entertainment. Epic political battles are waged over stop signs, barking dogs, and other matters of national significance.

Those looking for controlled-access communities, plush golf courses, and color-coordinated housing and residents need to look elsewhere because Tybee proudly embraces what locals call "Tybee Tacky." Take a stroll through the local legend department store bouillabaisse that is T.S. Chu's and I guarantee you won't be confused that you are in Neiman Marcus. One popular establishment, Earl's, remains prepared for any holiday by leaving all its decorations—Halloween, Thanksgiving, and Christmas—on display just in case. Status on Tybee goes to the person who has the most rustproof rims on his or her beach bicycle. Not that there isn't money on the island. You just can't tell by the locals' footwear, which is more frequently bare feet than Bruno Maglis.

No one's absolutely certain where the name "Tybee" originated. In the Yuchi Indian language, tybee means "salt." Some believe the name came from a Choctaw chief named Iti ubi, which means "wood killer." Some believe the name came from the corruption of the word "tabby," a oystershell-limestone mix that was used as a construction material by early colonists on the Georgia coast. Tybee, sometimes spelled Tiby on early maps, was first incorporated in 1887 as the town of Ocean City, and was known as Savannah Beach during its heyday as a resort for the city of Savannah. Today, it is incorporated as the town of Tybee.

Tybee has been the playground of Savannah's wealthier citizens for more than a century, and today the island's many beautiful homes with docks leading out to expensive watercraft testify to the fact that its popularity endures.

When the island became more accessible in the mid-1800s with the development of the steamboat, the general public started coming more often. Resort hotels, such as the Bolton Hotel and Ocean House, were established, and lots were sold for $200, plus $150–$200 for a frame house. Tybee's development as a resort picked up more steam after the Civil War, when public transportation to the island improved with the establishment of a rail link with Savannah in 1887. The three-hour steamboat journey was reduced to an hour train ride, if the train didn't break down. By the Roaring Twenties, more people called Tybee home, and thousands of visitors would come to the island in the summer.

Photos reveal that beach outings were quite a different sartorial event in the early 1900s. Men wore suit coats and long pants with ties and bowler hats while women wore fancy hats, fine long dresses, and high-heeled shoes—as dressed up as any Sunday church gathering today—as they walked on the beach.

Tybee was dominated by a cottage culture, with more than 400 summer residences built on the island. A photograph hanging in City Hall (a duplicate is also in the Tybee Museum) shows a row of cottages facing the beach behind a set of dunes from 11^th Street to 5^th Street, or the mid-beach area. These family cottages had wrap-around sleeping porches to take full advantage of cooling ocean breezes at night. The builders of these cottages wisely set them back behind the second dunes, looking for protection from storms. A sidewalk ran in front of these cottages, some of which featured grand wooden staircases centrally located and oriented toward the beach.

The fact that these early homeowners built back from the beach affected development patterns to come because the property in front of their houses became valuable. Since the 1960s and 1970s, ownership of many of these cottages has turned over from one generation to the next, with second generation family or developers developing four or five homes directly in front of these charming cottages.

As it usually happens with historic properties, some have fallen into neglect, others have been remodeled, obliterating their historic character with stucco and frosted windows, and others have been torn down to make way for half-a-million dollar homes. But some cottages retain their elegant beach character and a few of the residents have successfully resisted upgrading their free, natural cooling systems for air conditioning.

The main hub of social activity on Tybee Island was the Tybrisa Pavilion and the old and new Tybee Hotels (the first one burned), popular gathering sites at the south end of the beach. When the palm-lined Tybee highway was opened on June 21, 1923, linking Tybee with Thunderbolt, a new era was ushered in. In the 1920s and 1930s, Tybee Island was one of the busiest seaside resorts in the Southeast.

Butler Avenue at one time had a train running down the middle of it, with a turntable rail yard at the end near 17^th Street. The steam engine would drop its passenger cars, be turned around, then push the passengers back to Savannah. The Tybee Highway replaced the train tracks, and Butler became a wide, palm-lined, divided road. But the palms were cut down to make way for parking spaces on either side of the street, which added to municipal coffers but took away from the attractiveness of the avenue.

With the boom in population and recreation coming to all of America's shorelines, prosperity in the form of real estate development has had its effect on working class residents. Locals will quickly tell you a story of how a house and lot purchased for $15,000 only 20 years ago sold last week for over $300,000. One island native, Michael Bart, says Tybee Island has changed more in the last 10 years than the previous 50, with property taxes on a steady march upward. Because of the desirability of the beach, developers are staying busy with redevelopment on the island, tearing down older structures and filling in with new. Today, the sound of hammers and saws competes with the cries of seagulls as Tybee Island continues to change.

The Tybee Visitor Center and TAG Shop is found at US 80 and Campbell Avenue on the right as you approach Tybee's beaches. This is a good place to stop and inquire about lodging and events on the island, shop in the knick-knacky TAG Shop (Tybee Antiques and Gifts) that features local arts and antiques, buy some ice cream or baked goods, or purchase some fresh vegetables at a small farmers' market. It is open 7 days a week, 9–5. Phone (800) 868-2322 or (912) 786-5444.

Tybee Island's Natural Features

Ecologically, Tybee Island would be a great place to earn a Ph. D. on the effects of development to a barrier island. Barrier islands are very impermanent geological entities. The sand is always on the move, leaving to go somewhere else or arriving from somewhere else. Tybee Island is no different and the struggles the island has gone through to literally hold its ground are instructive for all barrier island communities.

Despite its small size and overdevelopment, Tybee Island surprisingly still has threatened loggerhead sea turtles nesting on its beaches—as many or more than St. Simons Island, another developed island. In 1998, three brave turtles nested on Tybee Island compared with a solitary individual on St. Simons Island. Not that this is anything to brag about, when considering historic numbers that probably reached the several hundreds before Europeans came to the coast. (Cumberland and Little Cumberland islands lead the Georgia coast with a combined 10-year average of 242 nests a year.)

Tybee Island's natural beach sand is not as fine and white as that of the beaches of the Gulf of Mexico because of Tybee Island's high organic mix and the quantity of rough dark granite in its sand. Beach sand on the Atlantic and Gulf coasts generally consists of three components: fine minerals, crushed seashells (calcium carbonate), and detritus from other dead organisms, including marine plants and animals. Low wave energy on the Georgia coast prevents heavy deposits of calcium carbonate and the sand grains found on the beach are rougher, due to a lack of rounding from wave energy.

The higher the quartz content, the finer and whiter the beach sand, such as you find near Grayton Beach, Florida. When you hear the sand squeak under your feet, that's the angular, translucent crystal of quartz rubbing together. This quartz has been brought down to the beach from the Appalachians. In essence, you are walking on the Blue Ridge Mountains when you are walking on a southeastern Atlantic or Gulf of Mexico beach. Some beaches, such as ones near St. Augustine and in the Bahamas, have a high calcium carbonate component and when viewed with a hand lens will be revealed as crushed sea shells.

Sand on a barrier island beach does not stay in one place for long. Wind, rivers, tides, and currents all play a role in growing, shaping, and destroying barrier islands. Tybee's mineral components have, over the millennia, come from the Appalachian Mountains via the Savannah River drainage. A mix of quartz and granite gives the beach a gray color. The black streaks are pulverized granite, washed down from the mountains.

The Savannah River has historically been a contributor to Tybee's beaches. But at least three major impoundments or dams trap sediments upstream from Tybee Island, keeping natural sediments from adding to the shoreline. Also, a deep channel cut, or trench, is maintained by the U.S. Army Corps of Engineers for the Savannah River Harbor, allowing large commercial freighters access to the Port of Savannah. This 42-foot-deep trench, which left to natural forces is 24 feet deep, traps southward-moving sands from South Carolina, preventing the natural renourishment that sustains and helps create the beaches. As the trench fills, dredging operations collect the sediments and move them to official Savannah Harbor Ocean Dredge Material Disposal Sites (ODMDS). The sediments, totaling 7 million cubic yards a year, are not all beach compatible. Some of them are, however, which leads some people to argue that the sandy component should be deposited on Tybee.

The bottom line is that Tybee Island, like many barrier islands in the U.S., has been losing beach, especially at the northeast end, as prevailing currents, tides, and winds have moved sand southward from the island. Take a walk north on the beach at high tide from the Tybee Pier and you will run into trouble as you pass Third Street on your left: you run out of beach. Over the years, officials have built more than 100 beach-trapping structures of different degrees of effectiveness in an ongoing effort to stop the island from losing its beach. In 1941, a sea wall was constructed along the length of Tybee on the eastern side from the north to the south end.

To help the situation, the U.S. Army Corps of Engineers periodically pumps sand from offshore "borrow" sites and transports it to eroding areas, a stopgap measure that costs usually a million dollars a square mile. Local governments pay approximately 5 percent, state and county taxpayers pitch in about 30 percent, and the federal government pays the rest. The Tybee beaches have been renourished several times. In 1975–1976, with the northeastern end in trouble from erosion not unlike it is today, a major renourishment project was launched to build up 3 miles of beach with sand from nearby shoals. Today, another round of renourishment is in the works, possibly from materials dredged from the Savannah River as it is deepened.

Beach renourishment changes the mix and look of the beach. Occasionally, beachcombers can find hardened clay balls washed up on the beach. These were created when renourishment operations pumped clay up on the beach, and waves rolled it into small, rounded, bricklike aggregate stones. Beach renourishment has a negative effect on burrowing sea life in the littoral zone, which in effect is buried alive when sand is pumped up on the beach.

Older strategies that employed sea jetties or groins to hold sand in place prove eventually to be disastrous. These structures, which run perpendicular to the shore, interrupt the normal littoral drift of sand and sediments, essentially robbing Peter to pay Paul, depriving down-coast areas of natural replenishment and causing erosion. This damming of the natural flow of the river of sand eventually causes severe erosion either in front or behind the jetty. Sea walls, which run parallel to the shore, protect structures directly behind them, but deflect and increase wave energy that eventually undercuts the structures and causes erosion. On the southern end of Tybee, beyond the seawall, there used to be 15-foot high dunes. After the renourishment project, the dunes washed away for 30 feet behind the seawall. Controlling barrier islands is unpredictable and some beaches grow despite of these structures.

As the sand builds up, pioneering plants that can tolerate salt spray, exposure to the sun, and tenuous soil conditions start to colonize an area. They trap blowing sand and eventually create a dune. As the dune stabilizes, a greater diversity of plants develops, with some plants on the exposed top of the dune (sea oats) and others in the more protected, moister bottom. On Tybee Island, a young Holocene island (4,000–5,000 years old) the best natural dunes are found on the North Beach area and in the Mid-Beach area around 10^th Street.

In the long run, barrier island beach-holding strategies can only have a temporary effect. Statistically, the Georgia coast should experience six major hurricanes a century. In the 1900s, Georgia has been lucky and not experienced even one, making homeowners and developers somewhat overconfident about their real estate investments. In the nineteenth century, the Georgia coast was hit by six major hurricanes. The most destructive was the hurricane of Aug. 27, 1881, which completely submerged Tybee Island under a 20-foot storm surge, destroying most of the island. Ominously, most experts believe it is only a matter of time before another one lands on the coast.

Bird-watching on Tybee Island

The North Beach area has traditionally seen the greatest variety of species, but new development has decreased sightings of shy species. Regardless, the north end is a stop on the Colonial Coast Birding Trail established by the Georgia Department of Natural Resources.

Seen at the north end, as well as on the rest of Tybee's beaches, have been Wilson's plovers in the summer, and during winter red knots, pectoral sandpipers; royal, sooty, Caspian, Sandwich, and gull-billed terns; black skimmers, dunlins, and piping and semipalmated plovers. Occasionally seen in summer flitting through tree canopies on the northern end are painted buntings and yellow-billed cuckoos, and in winter various warblers are uncommon visitors, including the orange-crowned. Common on the beach are ring-billed gulls, brown pelicans, black skimmers, and boat-tailed grackles. During the winter, migrating species are seen in the air heading south in their V-shaped formations. Rock jetties attract ruddy turnstones and purple sandpipers. The interior creeks on the western side are home to the American oystercatcher, which feasts on the exposed oyster beds at low tide. Dunlins and black-bellied plovers are seen here as well.

Information is from this site:  http://www.epa.gov/owow/estuaries/kids/about/index.htm

What is an Estuary?

An estuary is a body of water formed where freshwater from rivers and streams flows into the ocean, mixing with the seawater. Estuaries and the lands surrounding them are places of transition from land to sea, and from freshwater to saltwater. Although influenced by the tides, estuaries are protected from the full force of ocean waves, winds, and storms by the reefs, barrier islands, or fingers of land, mud, or sand that surround them.

• Barrier island. Refers to a long, narrow island running parallel to the mainland, built up by waves and currents and protecting the coast from erosion by surf and tidal surges.

Why Are Estuaries Important?

The sheltered waters of estuaries are home to countless plants and animals that like to live in water that is part fresh and part salty. Examples include horseshoe crabs, ospreys, manatees, mangroves, and seagrasses. Hundreds of fish and shellfish, such as scallops, shrimp, and salmon, live in estuaries at some point in their life. Estuaries protect water quality by filtering out dirt and pollution. In addition, estuaries and the land surrounding them are places where people live, sail, fish, swim, and bird watch. As a result, estuaries are often the centers of our coastal communities.

Information is from this site: http://www.mbgnet.net/salt/sandy/indexfr.htm

A Barrier Island - Bald Head Island

The What's It Like Where You Live? team visited Bald Head Island to do some explorations and shoot some videos. Along the way, they wrote this report:

Barrier Islands
Bald Head Island is a barrier island. To understand life on Bald Head Island, you must understand what is meant by barrier islands. 

Barrier islands are separated from the mainland by bodies of water that vary in size, from small estuaries to huge bays and sounds. 

Most of the barrier islands in the United States are found off the coast of North Carolina, South Carolina, and Florida. 

 A barrier island serves as a buffer or "barrier" between the coast and the sea. That means that they must experience not only tides, winds, and waves, but big storms and hurricanes, too.

These forces cause barrier islands to have a constant changing environment. The islands erode in one area, but build up in another. 

On barrier islands you will find several distinct zones. Each zone has special plant and animals that have adapted to the unique conditions.

Beaches
Beaches on barrier islands are sandy.

Dunes

Sand dunes are big mounds of sand behind ocean beaches. The dunes closest to the ocean are called primary dunes. The dunes behind the primary dunes are called secondary dunes. Dunes can occur in places other than barrier islands. Dunes protect barrier islands from wind, waves, and storms, just like barrier islands protect the mainland from the very same forces! 

Sea Oats are one of the few plants that will grow on primary dunes. The roots of sea oats hold the sand in place. The leaves stop and collect blowing sand. 

Without sea oats, dunes would be destroyed by storms, floods and wind. The name comes from the seeds on the top of the plant, which look very much like oats! 

Beach grass, like sea oats, grows on Bald Head Island. It looks like clumps of green grass and can be as high as three feet tall. It has long, thin, green leaves. When Beach Grass is planted on a dune, grains of sand collect around the plant as sand blows over the beach. The sand that gathers at the base of the plants stimulates more plant growth. The plant growth also stabilizes the sand dune and helps keep it from blowing away.

Maritime Forests
Trees are bent by the wind and salt spray and have a distinctive wedge shape. They have adapted to the harsh environment and have become salt-tolerant to survive. 

Trees and bushes you might find on Bald Head Island include live oak, loblolly pine, slash pine, yaupon holly, and red cedar.

Estuaries - Where Rivers Meet the Sea

An estuary is a partially enclosed body of water where incoming seawater is mixed with fresh water coming from the land. Examples of estuaries include bays, sounds, salt marshes, mangrove forests, mud flats, swamps, inlets, and sloughs.

Estuaries provide a transition from fresh water to salt water. A small disturbance in the habitat can have serious repercussions. Because of the difference in density between fresh and salt water, salt water will move into the estuary along the bottom, while fresh water will flow downstream to the ocean along the surface. This causes a layered condition.

Life in an Estuary
Life in an estuary is an interesting and diverse mix of land and sea creatures, and some animals. Mammals, birds, fish, reptiles, shellfish, and plants all interact in this ecosystem to create some very complex food webs. Birds are very common in estuaries because of the abundance of fish, worms, crabs and clams. The feeding is easy in an estuary. Inside the soil, sediment sand and mud are lots of microscopic bacteria. These lower level creatures thrive because of the plentiful decaying plant matter. Plants thrive because of the nutrient rich soil and the available water.

Many marine organisms depend on estuaries at some point during their development. Some fish only use estuaries at certain times of the year, while others use the natural protection for the laying of eggs. Most commercially valuable fish and shellfish spawn, nurse, or feed in estuaries.

Influence of Tides
Like other coastal communities, estuaries are dramatically influenced by tides. During the day time, when the tide is out, many aquatic creatures retreat into protective postures. Clams can close their shells, worms stay underground, while other creatures sleep. The change in temperature, the exposure to air and the vulnerability of being active during daytime are all reasons why some creatures are only active at night. Of course, some animals, like birds, are active during the low tide daytime because the supply of food is easier to get to.

At night when the tide returns the estuary comes alive. The returning sea water floods and submerges creeks, salt marshes, mud flats, mangroves, and estuaries. The water brings protection from predators. Many estuary creatures become active only at night.

A Water Filtration System
Rivers often contain lots of sediment, nutrients and pollutants. Estuaries remove sediments and nutrients before they reach the ocean. Otherwise, valuable top soil and nutrients would be flushed into the open seas where they could not be used again.

Flood & Storm Control
Estuaries act as natural buffers between the land and the ocean. Porous, resilient salt marsh soils and grasses absorb flood waters and dissipate storm surges. Like barrier islands, they protect the mainland and people from the brunt of heavy storms. Estuaries help protect human lives, upland animals, and real estate.