Seagrass Ecosystem of Lignumvitae Key

Meadow of Turtle Grass

In the Lignumvitae Key Management Area there is over 10,000 acres of seagrass habitat that are protected inside park waters. While the seagrass flats may not look like much to the casual observer, seagrass ecosystems are some of the most productive in the world and are vital to the Florida Keys ecosystem. Below are some fun seagrass facts you can use to impress your friends:

  • There are three types of seagrass most common in the Florida Keys, these are turtle grass, shoal grass and manatee grass.
  • Seagrass are flowering plants. The flowers are pollinated by the movement of the water over the grass beds. Recently scientists have discovered that small marine crustaceans also help to pollinate the flowers. Acting like bees, the tiny marine creatures carry sticky pollen grains on their backs as they visit the flowers to feed. Seagrass can also reproduce vegetatively, by spreading underground stems called “rhizomes.”
  • A diverse array of sea creatures live in the seagrass ecosystem. These include manatees, sea turtles, stingrays, crabs, snails, starfish, anemones and countless fish species. Many of these animals are experts at camouflage. Snorkelers must move slowly and be very patient to catch a glimpse of the creatures living in and among the blades of grass.
  • Seagrass is very important commercially, in fact, 70% of commercially important fish utilize seagrass ecosystems at some point in their life.
  • Seagrass helps keep water clear. The rhizomes hold bottom sediments in place and the blades help to trap fine sediments from the water column.

In Lignumvitae Key Botanical State Park, the seagrass ecosystem is one of the park’s greatest natural resources. To reduce impacts of propellers on the seagrass flats, all seagrass areas under 3 ft deep in state park waters are closed to combustion motors. However, anglers can still access the flats by tilting their motor up and polling into the shallows.

If you are planning to boat in the Islamorada area, refer to a navigation chart or GPS to plan your trip. Use the marked boating channels to travel inside the park water to help protect the precious seagrass ecosystem.