© 2025 WGCU News
PBS and NPR for Southwest Florida
Play Live Radio
Next Up:
0:00
0:00
0:00 0:00
Available On Air Stations

FGCU Researcher Reveals The Cause Of Red Tide During Lecture Series Speech

Andrea Perdomo
/
WGCU
Dr. William Mitsch at the first Moon Light on the Marsh Distinguished Lecture Series event of 2019, spoke about his research findings about the cause of red tide on Jan. 10.

During the height of this past summer’s toxic algae bloom, a team of researchers from Florida Gulf Coast University took water samples from the Gulf of Mexico, the Caloosahatchee river and Lake Okeechobee to try and identify a common source of pollution.

The samples were sent to a lab across the country for an isotopic analysis of their nitrogen compounds which FGCU lead researcher Dr. William Mitsch said is "a way of sort of tracing the source of pollution to where its happening."

Mitsch announced the test results during a lecture series discussion last night at the Everglades Wetland Research Park in Naples. 

“Take it to the bank," Mitsch said. "Red tide is mostly caused on our coastline by nitrate fertilizer.”

Mitsch said the highest reading for nitrates came from the Caloosahatchee River sample.

The second highest reading came from collected rainwater, which Mitsch said could explain how nitrates end up in the Gulf, where they feed the red tide algae present in the water.

“It could be polluted rainfall that’s causing red tide," Mitsch said. "Or at least accelerating it, or maybe starting it.”

Mitsch said he and his team will continue their research on toxic algae and water quality.

Andrea Perdomo is a reporter for WGCU News. She started her career in public radio as an intern for the Miami-based NPR station, WLRN. Andrea graduated from Florida International University, where she was a contributing writer for the student-run newspaper, The Panther Press, and was also a member of the university's Society of Professional Journalists chapter.
Trusted by over 30,000 local subscribers

Local News, Right Sized for Your Morning

Quick briefs when you are busy, deeper explainers when it matters, delivered early morning and curated by WGCU editors.

  • Environment
  • Local politics
  • Health
  • And more

Free and local. No spam. Unsubscribe anytime.

More from WGCU
  • A local public transit program is being called a success, after two years of a trial run.LeeTran said the ULTRA On Demand Transit program is working, and may be expanded.
  • The boardwalk connecting Florida Gulf Coast University’s South Village residential area to the academic core is temporarily closed to pedestrian use from dusk to dawn. The closure is due to an act of vandalism that damaged the lighting system, creating hazardous conditions overnight.
  • FGCU graduate 22-year-old Zoey Carter walked for her mother Wednesday.Jessica Carter -- her mother -- died at age 49 from breast cancer. “I'm walking here today in honor of my mom. She passed away last year after battling breast cancer for four years," she said. "We came here together two years ago, and she did the walk. So I'm finally back, just in her honor.” Zoey Carter fought back tears but gathered the strength to attend the Making Strides Against Breast Cancer Walk. She joined along with several thousand Southwest Floridians, awash in a sea of pink, at Paradise Coast Sports Complex in Collier County.