Seagrasses serve as a habitat and shelter for reef animals such as juvenile conch and lobsters and some fishes. They also provide food for many herbivorous reef fish and sea turtles. Their interwoven stems and roots serve as filters for the seawater, trapping and filtering large amounts of fine sediment. They provide sediment stabilization and seagrasses also help to prevent beach erosion by slowing down wave action.
Most of St. Maarten's seagrass beds were destroyed by hurricanes Luis and Marilyn in September 1995. The grass beds recovered over time but are under pressure from threats such as dredging, anchoring, nutrient and sediment load and other forms of pollution.
Seagrasses can be found at Simpson Bay, Great Bay, Little Bay and Simpson Bay Lagoon. There are seven types of seagrasses, three of which are found locally: paddle grass, manatee grass and the most common, turtle grass so called because it is the staple diet of the Green sea turtle.