Extinction. Rebirth. Resilience. All of these things can be said about the hardy little plant, Seabeach Amaranth, that lives on Assateague Island. In fact, this unassuming low-lying vegetation is one of the unique species endemic to our Coastal Bays. Seabeach Amaranth is native to the sandy Atlantic barrier islands along nine of the states on the Atlantic Ocean. It can be found as far north as Massachusetts and as far south as South Carolina.
While it doesn’t look like much, looks can be deceiving. Its small reddish stems and waxy, wrinkly leaves can be easily overlooked. But for four months, the petite yellow flowers and seeds, which are produced on the underside of the plant, are ready. And what are they ready for? Dispersal! The Seabeach Amaranth’s habitat isn’t where you’d normally find plants to begin with. It needs open and sparsely vegetated areas like those found on our barrier islands. These barrier islands have low plant diversity which is a necessary component for the success of the Amaranth. More specifically, it can be found on the upper beach areas, where dunes begin to rise away from the splashing waves.
How does Seabeach Amaranth succeed in such a dynamic environment? It’s due to something called overwash. Overwash is when ocean water rushes across islands during periods of high water and wind. When hurricanes and storms hit the islands, they reduce and eliminate other plants, and in doing so, it creates new habitat for plants to grow. These intense weather events disperse the seeds of the Amaranth. As the sand is deposited on the island’s interior, it covers up large areas of vegetation, which creates the prime habitat for amaranth so it can grow without competition. This needs to happen as amaranth can be easily outcompeted by more aggressive plants. Not only does overwash help the amaranth, but amaranth helps the island. By trapping sand with their roots, these plants help initiate dune formation and create habitat for other plants like sea oats and beach grass. They also provide ideal nesting environments for traveling birds like the Least Terns, Caspian Terns, and Piping Plover on Assateague.
In 1993, Seabeach Amaranth was listed as threatened on the US Endangered Species List. At the time, it was no longer found in six of the nine states that had previous populations due issues like overdevelopment and the stabilization of barrier islands. When it was added to this list, there were no known plants along Maryland’s coast. The last time that Seabeach Amaranth was found on Assateague was in 1967, which makes the discovery of a population on the northern end of the island in 1998 a wonderful surprise. This small population was the needed invitation to begin restoration efforts.
Restoration can be a difficult process, and the ups and downs of the re-establishment of the Seabeach Amaranth is a great example. Efforts have been somewhat successful, but have also been plagued by high mortality rates of plantings. Today, the range of plants is somewhere between 500 – 600 individuals. As the species grows at one of the lowest points on the continent and lowest points on the barrier islands, it lends insights into the effects of sea-level rise. Though they are small and seem to be fragile, their fierce resilience to one of the most dynamic environments makes them a marvel of the Coastal Bays.