Wetlands, Marshes and Swamps

Eel Creek

The nature trail at Sagamore Hill boasts multiple ecosystems from dense forest to the coastline of Cold Spring Harbor. In between the forest and coast, there is one of the few remaining salt marshes on Long Island known as Eel Creek. Theodore Roosevelt and his family spent many days down by Eel Creek enjoying the various flora and fauna that called it home.






Eel Creek is home to many wading birds, shorebirds, songbirds, and birds of prey. They include Great Blue Herons, Great Egret, Greater Yellowlegs, Belted Kingfish, Snowy Egret, Mallards, Black Ducks, Bald Eagles, and Osprey. It is also home to fiddler crabs, blue crabs, oysters, and mussels. Dune grasses of Eel Creek include both Saltwater (Smooth) Cordgrass, Saltmeadow Cordgrass, American Beach Grass, Little Bluestem, Goldenrod, and Sea Oats.

Salt marshes are the most productive ecosystems in North American because of their cyclical ability to protect, absorb, and transform. These marsh areas collect nitrogen from watershed and carbon from fossil fuel waste before they dangerously enter the nearby body of water; the marsh also converts these and other organic matter into nutrients that are vital for plants and organisms living in and above its soils.

Salt marshes contain bacteria, phytoplankton, and fungi that break down organic material such as dead leaves and grass that fall from the dense brush alongside them. During autumn, salt marshes are most productive given the large deposits of fallen leaves. First, these microorganisms break down the organic material so it can be absorbed by detritovores, or organisms that feed off dead organic matter such as clams, oysters, and mollusks. Then, these detritovores act as filters for nutrients essential to larger predators living in marsh areas such as crabs and shorebirds.

The ebb and flow of water with high and low tide allow for excess matter to be cleaned and new matter to be processed. During low tide, when the channels are drained, mussels will appear and there will be small holes in the mud. Crabs, such as the fiddler crabs, continue to dig these holes to feed on the algae and bacteria beneath. Then, when the tide rises, these larger holes allow for more oxygenated water and nutrients to flow deeper into the ground. When the high tide fills the channels, minnows, killifish, and other small fish swim inside providing additional food sources for shorebirds and wading birds.

Salt marshes are also made up of sturdy grasses and hardy plants. Due to the harsh environment of heavy winds, waves, saltwater, and direct sunlight, few plants can survive. Therefore, the plants that do are vital to the survival of the marsh. These plants have adapted to live in this environment with waxy coatings to repel water or thin leaves to bend and withstand heavy winds.

Dune grasses and marsh plants, such as American beach grass, cordgrass, and glasswort, act as anchors for the sand so it stays in place and gradually builds into dunes. Many of these grasses have intricate underground stem systems which spread roots horizontally, known as rhizomes. With these rhizomes in place, sands, sediment, and algae collects which creates dunes. These dunes then protect inner areas of the shoreline from destruction from harsh winds and large waves, allowing the salt marsh to continue to exist.

Even though adaptable, salt marshes are fragile and extremely suspectable to human impact. When dunes and their grasses are disturbed, they cannot protect the inner areas and channels from rising tides and powerful storms which could, in turn, disrupt food cycles and cause native fauna to not return. Therefore, it is important to stay on trails and not walk in protected areas. Remember to be stewards of your public lands when enjoying the nature trail at Sagamore Hill.