Turtle Grass

Common Name: Turtle Grass
Scientific Name: Thalassia testudinum

Family: Hydrocharitaceae - aquatic plants
Class: Angiospermae - flowering plants

Conservation status: Least concern, population stable
Sighting: Very frequent, all over Biscayne Key

Turtle grass is the first thing you'll find when you snorkel in Key Biscayne. It is specially abundant in Bill Baggs Cape Park, starting a few feet from the shore. Also in Crandon park, as soon as the sand starts to get covered by green, that is mainly Turtle Grass.
After a strong storm, you will also find large amounts of turtle grass leaves in the seashore, creating a brown dam, in same cases up to a couple feet high.  

As you can read in the links, turtle grass is actually a flowering plan, growing from a rhizome. The name comes form the Green turtle (Chelonia mydas), that feeds on the grass, although is a natural habitat for many animals, and feeds multiple herbivorous fishes of the florida waters, some of which eat the algae that grows in their leaves, rather than the seaweed itself. And of course, manatees graze turtle grass!

Although it looks uneventful, almost boring, if you look carefully, you can discover a variety of creatures hiding in the beds of turtle grass. Starting with other seaweeds and algae, sponges, crabs, conchs, and many different solitary swimming fishes, like pufferfishes. 

In the Crandon park area, turtle grass grows large, specially in the shallow waters on the left of the main beach, by the natural park protected areas.

The interface between the higher beds of turtle grass and the clear sand , like the one in the picture at the right, are also great areas to see all sorts of fish, hiding in the dark shadows created by the turtle grass. If you are patient and quiet, once your the shock for your presence is over, small and larger fishes will start swimming out of the shadows, making for a great beginner snorkeling experience.