Scientists are investigating a phenomenon in the Florida Keys where over 30 species of fish, including endangered sawfish, are spinning uncontrollably and dying. While some researchers point to record-high levels of the neurotoxin-producing algae Gambierdiscus, others cite "off-the-charts" ocean heat. A separate study found that 100% of bonefish tested in the area contained traces of human pharmaceuticals, including opioids and antidepressants.

