Estuaries and Seagrass: Function, Importance, and Protection

Brooke Saari
Sea Grant Extension Agent
Okaloosa & Walton Counties
bsaari@ufl.edu

Choctawhatchee Bay is one of the many natural resources we have here in Okaloosa and Walton County.  It is considered an estuary, which is a semi-enclosed body of water where freshwater and saltwater mix.  The salt content of the bay water varies from freshwater sources to the saltwater inputs, creating a mixture of freshwater and saltwater called brackish.  These areas are considered to be one of the most productive ecosystems in the world.  About 70% of Florida’s sport fish species spend the first part of their lives in estuaries. 

Choctawhatchee Bay is an estuary with salt marshes and submerged seagrass. Photo Credits: Brooke Saari

In Choctawhatchee Bay, one of the habitats that serve as the nursery grounds for many of these fish and other various organisms are seagrass beds.  Seagrasses are green plants that spend their entire lives submerged, and require light to live.  These areas serve many functions that have environmental as well as economic benefits.  Seagrass beds filter sediments by trapping them with their leaves to help maintain the clarity of the estuary.  These areas also provide shelter for many organisms and nursery grounds for the economically important sport fish.  Seagrasses also provide stabilization of the sediments through their extensive root systems, which provides a line of defense for the mainland during storm events through dissipating wave energies.  In addition to all of these functions the seagrass and many of its inhabitants serve as food, making these areas very important for the food chain. 

Many species utilize seagrass beds.

Though these habitats serve all of these beneficial functions, they are still fragile and declining worldwide.  The main threats to seagrasses are water quality degradation, sedimentation and propeller scarring.  There are ways for you to help these estuaries and its sensitive habitats.  Become aware, be a good steward, participate in clean-ups, and avoid sensitive habitat areas.  Choctawhatchee Bay is a wonderful area that we are lucky to have in our backyard.  The most important thing you can do for your natural resources is to learn about their uses, functions, and importance.  Knowledge is a very useful tool.