Shifting sands

Dynamic and beautiful, barrier islands naturally migrate inland, always changing shape on both ends in an everlasting dance with the sea. The Atlantic Barrier Island System starts at Plum Island, Massachusetts, and continues all the way to the southernmost tip of Florida and the Florida Keys, wrapping around the west coast of the state and then running northwest to Texas along the Gulf of Mexico. This barrier island system is one of the longest and most extensive in the world.

Barrier islands are long, narrow stretches of land separated from the mainland by salt marshes and lagoons, running parallel to the mainland coast. These islands are loved by wildlife and people alike, and are especially prized for their beauty and recreational opportunities. Estuaries, or salt marshes, provide critical habitat for juvenile aquatic species, as well as for commercial and recreational fishing. The beaches provide residents and visitors with lots of summer fun, spring picnics and many wonderful winter walks on the beach.

From the ocean to the estuary, there are several features typical of barrier island anatomy. Starting offshore, large sandbars first encounter the energy of Atlantic swells. Next, the beach zone is where wave action occurs, causing both sand accumulation and erosion, depending on the size of the waves. Behind the beach are the primary sand dunes, which are the least stable. This is where the sea oats, railroad vine, rabbit briar and cacti grow. On Amelia Island, we protect this fragile ecosystem with more than 40 boardwalks to the beach so human access does not destroy the dunes. The secondary and tertiary dunes are not protected, and it is rare to find them intact or undeveloped on our island, Fort Clinch State Park being the exception. Up and over the tertiary dunes, we reach the back side of the island, where waters are calm, fiddler crabs are abundant in the mudflats and oysters grow. Looking out to the west, we see the extensive salt marsh that spreads out in a sea of green and gold beyond the island.

Barrier islands are an exciting place to live; there is a lot of action. Throughout the year, the beaches regularly change shape, shifting with the longshore currents, wind, rain and tides. Wave action from hurricane swells and nor'easters also erodes them, driving inlet migration and sand spit growth. These islands are the natural shock absorbers for the mainland, constantly under assault.

Modern humans seem to want things to stay the same, but on a barrier island, change is inevitable. We can live on migrating islands successfully with community planning, preparedness and understanding their science. Indigenous residents lived on these islands for thousands of years and knew how to roll with the punches. They did not build permanent structures of concrete and were able to adapt to the shifting shorelines, something modern humans have a very hard time with.

With so much development on Amelia Island, we are running out of room to be flexible or move out of the way of natural events. Like coastal towns all over the country, we clearly need a buffer zone; we can no longer justify building so close to dynamic water systems like coastlines and rivers. Science, lived experience and observation over time tell us otherwise. Buffer zones can give the environment room to do what it naturally does: change.

Most residents on Amelia Island would prefer the movement to stop, but that is not how barrier islands work; they are temporal as sand travels from one island to the next. That is why jetties were built to protect the entrance of the St. Marys River that separates Amelia Island from Cumberland Island National Seashore. The Trident ballistic missile submarines enter and leave Naval Submarine Base Kings Bay, in Georgia’s salt marsh. Sand gets trapped on the Cumberland side, and the deep channel dredged between the islands stops the natural migration of sand from Cumberland Island to Amelia Island. This causes beach erosion on our island and starves it of sand.

A day trip to Georgia’s Cumberland Island National Seashore or Little Talbot Island and Big Talbot Island state parks in Jacksonville, Florida, is a great way to see intact barrier islands. We are so fortunate to be surrounded by these gorgeous, peaceful and unique places.

I used to love to visit a stand of old pine trees on Big Talbot Island’s northern shore, but they no longer exist. In my short 26 years in Florida, I have seen a lot of natural change on our local barrier islands, and lots of change caused by humans.

Trying to make an impermanent shoreline permanent will only be temporary and expensive, as Mother Nature continues to force change on us. I believe humans will become more creative, resilient and intelligent when rising to the challenges we face. We can embrace or resist changing conditions, but we cannot stop them. With rising sea levels, we have added insult to injury. We may want to start cooperating and find innovative ways to work with the forces of nature, not against them.