Non-toxic blue-green algae at Robinson Preserve

Non-toxic blue-green algae at Robinson Preserve
Non-toxic blue-green algae is present at Robinson Preserve, according to DEP. - Florida Department of Environmental Protection | Submitted

BRADENTON – Non-toxic blue-green algae is present at Robinson Preserve, according to today’s report from the Florida Department of Environmental Protection (DEP).

Filamentous cyanobacteria (Lyngbya-like) was found on Monday, June 10, according to the report.

Non-toxic blue-green algae at Robinson Preserve
Non-toxic blue-green algae is present at Robinson Preserve, according to DEP. – Florida Department of Environmental Protection | Submitted

The same type of blue-green algae was first found locally in Holmes Beach waters on Thursday, May 9 in Anna Maria Sound at Key Royale and in the Intracoastal Waterway south of Grassy Point, and in Palma Sola Bay near San Remo Shores.

No toxins have been detected in any of the blue-green algae samples collected in Manatee County through Friday, June 14, according to DEP.

The two algae species found in Manatee County waters are not the same species that has plagued Lake Okeechobee, microcystis aeruginosa, according to DEP.

Of eight sites tested statewide from June 7-13 by DEP, one – in Hillsborough County – was positive for toxins.

Blue-green algae can be blue, green, brown or red and emit a foul, rotten egg odor caused by the production of hydrogen sulfide gas, according to DEP, which advises staying out of water where algae is visible as specks, mats or water is discolored pea-green, blue-green or brownish-red. Additionally, pets or livestock should not come into contact with the algal bloom-impacted water, or the algal bloom material or fish on the shoreline.

Even non-toxic blooms can harm the environment by depleting oxygen levels in the water column and reducing the amount of light that reaches submerged plants, according to DEP.

The growth of blue-green algae typically increases in the spring and summer months when water temperatures and daylight hours increase.

Red tide report

No significant red tide is forecast in Manatee County waters through Monday, June 17, according to today’s Florida Fish and Wildlife Conservation Commission (FWC) report.

Background concentrations of red tide were found in water samples off Mead Point at Robinson Preserve in Bradenton on Tuesday, June 11, according to the report.

Background concentrations of the algae that causes Florida red tide, Karenia brevis, have no discernable effects on people or marine life, according to the FWC. However, in very low concentrations and above, red tide cells emit a neurotoxin when they bloom that can cause shellfish closures and respiratory irritation in people, especially those with asthma, COPD or emphysema. In low concentrations and above, red tide can be deadly to marine life.

No fish kills were reported this week.

Scientists say that salinity, currents, temperature and light play a part in the formation of red tide blooms, as do nutrients from Florida’s natural phosphate and limestone deposits, Caribbean seawater brought to Florida’s west coast on the Loop Current, the Mississippi River, Saharan dust blown across the Atlantic Ocean to Florida’s waters, and fertilizer and animal waste runoff.

To help keep algae growth at bay, Florida law bans the use of phosphorus and nitrogen fertilizers during the rainy season, June 1 through Sept. 30.

Report algae blooms to DEP at 855-305-3903 or online. Report fish kills to FWC at 800-636-0511.