Stay in the know about wildlife, water quality, and ecosystems on Sanibel and Captiva Islands and in Southwest Florida
Cold Snap Similar to Snook Die Off in 2010
In the winter of 2010, the region around Sanibel experienced a cold snap intense enough to kill great numbers of semitropical aquatic life. Over the past week, SCCF’s River, Estuary, and Coastal Observing Network (RECON) once again captured similar temperatures, and scientists have documented marine life fatalities.
Water temperatures are now rising but remain below 60 degrees (F).
“Hopefully, this cold event will end soon, and the die-off of creatures will subside,” said SCCF Research Associate Mark Thompson.
“Currently, the beaches are littered with invertebrates, such as the 9-armed sea star, sea cucumbers, urchins, hermit crabs, stone crabs, tunicates, and many others. Folks have also noted several species of cold-stunned sharks, jacks, midshipmen, blennies, and batfish, to name a few.”
However, reports of die-offs are nowhere near 2010 levels.
Extensive Fish Kills & Cold Stunning of Sea Turtles
In 2010, Thompson and his colleagues at the SCCF Marine Lab documented dead goliath grouper in Clam Bayou, masses of floating dead snook throughout Pine Island Sound, and numerous other fish and invertebrates that died due to extreme cold.
SCCF’s sea turtle team received many calls related to cold-stunned loggerheads floating in the vicinity.
From Jan. 3-19, 2010, the local water temperatures were in the 40s and 50s for over two weeks, causing a massive snook die off — estimated at millions of fish statewide.
The Florida Fish and Wildlife Conservation Commission (FWC) was forced to ban snook fishing for four years to allow the population to recover.
Similar Water Temps Now
This year, RECON has recorded similar water temperatures around Sanibel. Currently, the temperature has been between 47 and 60 for about one week.
“The lowest temperature recorded in 2010 by our RECON monitoring system was 46,” said Thompson. “Snook are in danger when water temperatures drop into the 50s. A temperature of 50 or below becomes lethal to snook. They will seek warmer waters, but when temperatures plunge regionwide, they may not be able to find sanctuary.”
Snook fatalities were not observed by SCCF scientists this week. And, the sea turtle team has not received reports of any cold-stunned turtles.
But a walk this week on Sanibel beaches demonstrated the effects of low temperatures on local marine life, as pictured below.
Check out real-time water temperature monitoring at RECON>>>
Take a beach walk with our marine science educators to learn what’s washing up>>>