fish kill

Nearly two years after an unprecedented die-off of endangered smalltooth sawfish in the Florida Keys, scientists are still investigating conditions that caused the deaths and how to better predict and prevent future outbreaks. “We're gonna probably have this tax on the sawfish population indefinitely," a marine biologist told WLRN.

One sawfish died and three were reported in distress in waters around the Florida Keys in April.

This winter's deaths come nearly six months after a mysteriously ailment linked to toxic algae killed more than 50 endangered sawfish around the Florida Keys.

In a report Tuesday, the Florida Keys Wildlife Research Institute said no new sawfish deaths have been reported since June. But exactly what caused the startling behavior remains unknown.

Wildlife officials said after more than three weeks of care at Mote Marine Lab in Sarasota, the sawfish — brought in after first-of-its kind rescue — was euthanized as its condition deteriorated.

Florida Fish and Wildlife Conservation Commission officials hope they are seeing decreased incidents of what are described as “erratically spinning fish” and smalltooth sawfish deaths in the Florida Keys.

With the cause still unknown, the number of rare dead sawfish in the Florida Keys rose to 40 this week, while officials say over 50 species have been affected. But a rescued fish pulled from waters off Cudjoe Key earlier this month is recovering under veterinary care.

Records obtained by WLRN from the Florida Fish and Wildlife Conservation Commission show state staff scrambling to respond to an alarming number of sick and dead sawfish, with as many as seven reports on a single day. As of March 20, 27 have been confirmed dead.

Sawfish, and about 30 other species of fish, are turning up sick and dying in the Lower Keys as questions mount over what's causing it. As word and worries spread, scientists are yet to find a smoking gun.

The number of reports of dead or dying endangered sawfish has risen to 39, with 15 bodies retrieved for testing, state wildlife officials said Tuesday.

Scientists say the fish kill that started in November and spread among dozens of species is unlike anything they've seen before.

Satellite images of red tide blooms in the Gulf of Mexico and modeling from within the water column will then be combined with a foodweb model to estimate mortality rates of different fish species.