Listening stations helping to evaluate red tide effect on Sarasota Bay

A network of listening stations in Sarasota Bay, Florida, is letting scientists hear how red tides affect marine life.

Underwater, Florida’s Sarasota Bay is a cacophony of frying bacon, clacking typewriters, knocking wood. But in August 2018, an unrelenting algal bloom known as a red tide swept across the bay. The algae produced a neurotoxin that stifled the bay’s snapping shrimp, toad fish, bottlenose dolphins, manatees, and other noisy denizens. Within days of the bloom, the water hushed.

Right away, scientists picked up on the sudden quiet, thanks to two solar-powered recording devices. These were the first in a network of passive acoustic listening stations—PALS, for short—set up in 2017 to eavesdrop on the bay’s undersea comings and goings. First conceived to monitor dolphin acoustics, the PALS network is enabling scientists to explore all manner of effects on the marine soundscape.

Now, a new study shows how the PALS can help scientists rapidly detect ecological changes during harmful algal blooms.