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Macroalgae Study Continues at Refuge

April 20, 2022

SCCF’s Marine Lab has focused on water quality and seagrass habitat conditions in J.N. “Ding” Darling National Wildlife Refuge for more than a decade. Our lab facility was built in partnership with Ding Darling and the U.S. Fish and Wildlife Service (FWS).

Together, we are working every year to document the conditions and observe the marine flora that so many wading birds, fish, and other wildlife depend upon. Refuge biological technician Avery Renshaw has provided assistance in sampling nine locations throughout the refuge. At each transect, a quadrat is used to estimate the macroalgae percent cover.

The macroalgae are collected and returned to the lab for processing. The goal of the project is to document macroalgae, which is an indicator of the nutrient condition of the estuary. Too much algae means that there is too much nitrogen in the water. While J.N. “Ding” Darling has a pristine watershed, the refuge is affected by the high nutrient flows from the Caloosahatchee and Lake Okeechobee. The appearance of a carpet-like green algal species, Caulerpa fastigiata, near Wildlife Dive in 2018 has contributed to an increasing trend in macroalgae biomass in the refuge.

There are typically 5-10 species at each location, which are carefully sorted (this year with the help of volunteers), identified, and weighed. The results will be compiled in an anuual briefing to the U.S. FWS. 

Photo by Shane Antalick


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