Red Tide is back in SW Florida

My title is a bit misleading. Florida red tide (blooms of the toxic dinoflagellate alga Karenia brevis) has actually been skulking around west and southwest Florida since last summer. But because of the wind and current patterns it has mostly stayed to our north and offshore... until now.

Karenia brevis blooms are tricky to understand and predict because they usually start far offshore, fueled by nutrients from deep water currents that brush along the "continental shelf" of west Florida. But when winds and currents bring the blooms closer to shore, they interact with nutrient sources from the land; the flow from polluted rivers and runoff. There is a growing scientific consensus that while Florida's red tides may not be *initiated* by pollution, they are definitely worsened by pollution.

As paddleboarding marine biologist I'm out in the water a lot, so I get a lot of reminders of what's at stake; what we have to lose if we don't get our pollution under control and tamp down these red tides. For example, last week when paddleboarding around Lover's Key the water was relatively clear and I saw a cute little bonnethead shark swimming along over the sand. Today, paddling the same route with a friend, there were dead fish floating everywhere and a stench was in the air; a mix of rotting fish and the aerosolized "brevitoxins" of the red tide bloom. When we paddled over the same patch of sand where I'd seen the baby shark last week, there it was again, or another one about the same size, freshly dead.