Algae blooms have taken their toll on the Indian River Lagoon, and the Florida Fish and Wildlife Conservation Commission is finally taking an aggressive approach toward helping the ailing estuary.
Researchers with the state agency are using a new approach to more quickly detect and track algae blooms in the lagoon, which runs 156 miles from Jupiter north to New Smyrna Beach and makes up 40 percent of Florida’s east coast.
On a good day, the river offers terrific fishing for snook, sea trout, redfish, jacks and tarpon, as well as commercial clam and oyster farming. But algae blooms can make the river seem like a desert, with smelly, brown water and few signs of life.
In 2012, a bloom wiped out virtually all the seagrass in the Indian River from Melbourne to Vero Beach. The lush grass flats that supported everything from shrimp and crabs to the aforementioned gamefish disappeared, and so did most of the fish. About the only fishing to be had in that region is around spoil islands and isolated patches of seagrass.
The algae blooms are fueled by lawn fertilizer, sewage and storm runoff that ends up in the river. Flood control canals that dump fresh water into the lagoon after heavy rainstorms also enable algae growth by lowering salinity levels.
This year, the FWC established a flow-through monitoring program that analyzes water quality while the FWC research vessel is traveling throughout the lagoon. In the past, researchers had to collect water samples and examine them back at a laboratory. The flow-through system pumps surface water through instruments that measure its salinity, temperature and chlorophyll fluorescence, which is an indicator of algae. The information then is integrated with GPS coordinates to create maps of the river that show where algae blooms are located.
The real-time data allows researchers to sample blooms as they are noticed. At select stations, researchers collect samples to be analyzed for the amount and diversity of algae, a program that is done in partnership with the St. Johns River Water Management District and the University of Florida.
Besides quickly detecting algae blooms, it is hoped the information will help identify the causes of the blooms, ultimately leading to better management strategies for the river and the return of its seagrass and fish.
The FWC also is trying to figure out what causes algae blooms along the Gulf coast. Scientists at the agency’s Fish and Wildlife Research Institute are conducting a time-series monitoring project to discover when, where and under what conditions algae blooms occur. The project collects data at relatively uniform intervals over long periods of time at five sites from St. Petersburg to Clearwater. Each week, scientists gather water samples and measure their salinity, temperature, dissolved oxygen, pH and nutrient concentrations, as well as the types and amounts of algae. Ideally, the project will allow scientists to better understand how ecosystems change through time and are influenced by climatic events such as an El Niño.
As scientists learn more about algae blooms, they might be able to use the information to identify environmental conditions favorable for blooms, which may aid in bloom forecasting.