The Sanibel-Captiva Conservation Foundation reported that Karenia brevis – the organism that blooms into red tide – recently was documented during water sampling in nearby areas.

According to the SCCF, research scientists from the Marine Lab collected water samples on a short cruise on Oct. 15 to the lower Caloosahatchee, San Carlos Bay and into the Gulf of Mexico. The results indicated that Karenia brevis was present at all sites sampled.

The maximum concentration was 880,000 cells/liter, found two miles offshore of Tarpon Bay Road Beach. Levels higher than 100,000 can result in fish kills and respiratory irritation in humans.

Since September 2018, the SCCF Marine Lab has been systematically sampling the Caloosahatchee and Gulf for nutrients, phytoplankton and water quality. A total of nine trips have been completed, with one more planned, under a National Science Foundation RAPID grant to study harmful algal blooms.

The grant is intended to investigate how the intensity of red tide blooms is “related to nutrients in freshwater releases from Lake Okeechobee, a large inland lake in south-central Florida that is managed for flood prevention,” SCCF reported. The research will contribute to the lack of “strong scientific evidence to support the connection between the red tide and Lake Okeechobee water releases.”

The project’s aim is to provide water quality data prior to and throughout major freshwater releases. The data will provide insight into cause-and-effect relationships between the releases and HABs.

Dr. Natalie Nelson, with NC State University, and Dr. Ed Phlips, with the University of Florida, are project collaborators on the grant with Dr. Eric Milbrandt, director of the SCCF Marine Lab.

Marine Lab researchers were planning to do a more expansive cruise next week into the Gulf from North Captiva to Sanibel, according to the SCCF.