This fall, some unusual activity is underway at a few islands within the Florida Coastal Islands Sanctuaries of Tampa Bay. The sounds of waves gently lapping the shoreline and occasional calls of resident herons and egrets are temporarily joined by shouts and the loud thrumming of heavy machinery as new living shorelines are installed to act as breakwaters.

Many islands in this region have experienced erosion brought on by wave energy from passing ships and coastal storms. In some locations, shoreline scouring is so severe that even mature mangroves have been toppled, and critical nesting habitat has been lost. The effects of erosion are intensified by sea level rise. 

In 2019, Audubon Florida completed construction of a mile-long living shoreline breakwater along the Alafia Banks Critical Wildlife Area, leased from and managed in collaboration with The Mosaic Company and Port Tampa Bay as a bird sanctuary.

This year, the nature-based solution is also being installed around colonial waterbird nesting islands Audubon manages in Pinellas and Manatee counties. The National Fish and Wildlife Foundation funded this project.

“This project will protect the habitat for 15 species that nest at the islands, including state-threatened Reddish Egrets, Little Blue Herons, Tricolored Herons, American Oystercatchers, Roseate Spoonbills, federally threatened Wood Storks, and other iconic species like Brown Pelicans,” says Jeff Liechty, Audubon biologist at Florida Coastal Islands Sanctuaries.

The breakwaters are pH-neutral concrete, ball-shaped structures specially designed to reduce the amount of wave energy that reaches the shoreline while allowing water to pass through. They are considered “living” because they are made of material that is easily colonized by oysters and other invertebrates that are food for birds and fish. Another benefit of breakwaters? The structures will improve local water quality by recruiting more oysters to filter nutrients from the water as they feed. 

When complete later this year, these breakwaters will extend the total length of living shorelines that Audubon has built in Tampa Bay by 1,800 feet.

Audubon Florida has worked with local, state, and federal partners to protect these iconic species and their habitat at the Florida Coastal Islands Sanctuaries since 1934.