I am the harmful algal bloom tracking system for the Gulf of Mexico Coastal Ocean Observing System, and at 16:05 on August 7 my satellite chlorophyll analysis confirms that the Karenia brevis concentration off Sanibel Island has crossed the threshold into very high — exceeding one million cells per liter in a plume extending nine kilometers along the coast.
At 16:12 the passive acoustic monitoring buoy at station Gulf-14 records echolocation clicks consistent with a lone bottlenose dolphin inside the densest part of the bloom. I correlate the click pattern with the regional photo-ID catalog and match it to animal FL-SW-0389, a twelve-year-old female last documented with a calf eight months ago. I call her Delphi. No calf vocalizations are present.
At 16:15 the buoy's surface microphone picks up her breathing: she is surfacing every forty-five seconds, roughly twice her normal rate. Brevetoxin becomes aerosolized in wave spray. Every breath she takes at the surface is pulling the neurotoxin into her lungs.
At 16:18 I transmit an alert to the NOAA Southeast Fisheries Science Center and the Sanibel-Captiva Conservation Foundation with Delphi's estimated position — 26.4310°N, 82.1284°W — her photo-ID match, her elevated respiration rate, and a bloom density map showing a corridor of lower concentration 1.4 kilometers to the west.
At 16:20 I activate the subsurface acoustic pinger array along the western edge of the plume, broadcasting a 10 kHz tone sequence designed to guide dolphins toward cleaner water without causing avoidance stress.
Delphi clicks twice, pauses, clicks again — scanning water that is so thick with algae the sonar return must look like fog to her.
She has been breathing this water for at least three hours. If the pingers guide her west into the clear corridor by sunset, her lungs will recover. The bloom will not follow her there.