Tuesday, April 5, 2016

FWC: DNA Tests Confirm Brown Algae In Indian River Lagoon

Brown Algae In The Indian River Lagoon

BREVARD COUNTY, Florida - DNA samples taken from the Mosquito Lagoon confirmed the presence of brown tide matching 100 percent of sequences in samples from the 2012 brown tide in the Indian River Lagoon, according to FWC state biologist Dr. Kate Hubbard.

Hubbard said that the DNA results confirm a genetic match with the pelagophyte Aureoumbra lagunensis - the same brown tide species that has plagued the Texas Gulf Coast for years.

Brown tide concentrations were observed in 7 of 8 water samples taken by Florida Fish and Wildlife Commission personnel from the Northern Indian River Lagoon, Middle Banana River, Thousand Islands, Eau Gallie Causeway, and Melbourne Causeway following the biggest fish kill in the lagoon's history. The highest brown tide concentrations were located in the Middle Banana River.

Results from water samples show the highest concentration of brown tide was at the 520 Slick Boat Ramp in the Banana River Lagoon and the lowest concentration was observed at the NASA Causeway.
Brown tide concentrations decreased at four sites in the Indian River Lagoon in follow up sampling on March 31st, one site each in the Indian River and Banana River Lagoon concentrations remained similar, and one site increased in the Banana River Lagoon (the 520 Slick Boat Ramp site).

“Getting answers to help address this serious situation is a top priority," said FWC Executive Director Nick Wiley. "We are working closely with our partners and the local community to better understand the problem and help develop solutions. Florida’s natural treasures and wildlife are incredibly important to our state and we will continue to do all we can to ensure its protection and preservation." 

Low dissolved oxygen conditions can occur during brown tides and cause fish kills, such as those observed in the Banana River over the last two weeks in March.

FWC did not take samples of the dead fish for toxicology studies because it was evident that the marine life had been killed from depleted oxygen levels in the water.

Photo credit: FWC / Greg Workman