Long Island Sound, including New Haven Harbor, is an estuary where fresh and salt water meet, and at Lighthouse Point Park its forest, tidal marsh, rocky coast, sandy beach, and underwater habitats support a wide variety of life. The intertidal zone, covered at high tide and dry at low tide, is home to plants and animals adapted to both salt water and dry air, including Irish moss, rockweed, sea lettuce, hermit crabs, tiny shrimp, periwinkles, and Atlantic dogwinkles that bore through barnacle and mussel shells with a radula and digest them with enzymes. Some of the earliest scientific research on the intertidal zone was conducted by Addison E. Verrill, Yale University’s first professor of zoology and a curator at the Peabody Museum of Natural History, who studied the New England coast in the late 19th century. In the Sound’s waters live lobsters, clams, scallops, starfish, kelp, and fish such as northern and striped sea robins, tautog, bluefish, scup, menhaden, butterfish, striped bass, and winter flounder, whose left eye gradually moves to the right side of its head as it matures and whose flat body and mottled coloring help it blend into the bottom. Horseshoe crabs, animals little changed for 350 million years and more closely related to spiders than to crabs, come onto the beach in late spring to breed. Where Morris Creek empties into the Sound, a tidal marsh shelters mussels, crabs, fish, snails, and shrimp, provides foraging areas for birds, foxes, and muskrats, buffers the coastline during severe storms, serves as a nursery for many small fish and other organisms, and filters contaminants from the water, though invasive Phragmites australis crowds out native marsh plants. The park’s oak-hickory forest is especially important during fall migration as a resting place for birds flying thousands of miles. Along the rocky shoreline, gulls crack open hard-shelled mollusks by dropping them on rocks, while least terns, common terns, roseate terns, and double-crested cormorants fish along the shore and in the water.