The Florida Keys lost sponges—and several functions with them
WHAT THE EVIDENCE SAYS
Comparing Florida Keys hardbottom surveys from 2002 through 2018, researchers report 66% lower sponge abundance and 34% lower species diversity; declines also occurred outside documented lethal cyanobacterial blooms. Additional site surveys and experiments implicate lost sponge function in filtration, settlement substrates, underwater sound and changing sediment conditions.
WHY IT MATTERS / OUR READ
The mapped seafloor habitat can retain its category after the organisms that make it function have declined. Monitoring should test water filtration, larval settlement, acoustic conditions and substrate rather than stop at habitat cover.
CAVEATS / UNCERTAINTY
Some functions are inferred through separate experiments or extrapolations, not measured as a long historical time series. Multiple coastal pressures prohibit attributing all change to one cause.
SOURCE
Frontiers in Marine Science — Butler, 30 October 2026
View original evidence ↗
Hardbottom comparisons connect depleted sponge habitat with changed soundscape, bottom conditions and filtration.
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