Brevetoxin is a powerful irritant that attacks part of the nervous system, specifically the diaphragm, which controls breathing. The persistent algae blooms observed in Florida Bay since 1991 are typically caused by a far less toxic blue-green algae. These green algae blooms are not considered a direct threat to manatees. There were approximately three thousand manatees in Florida waters this winter with half the population located on the east coast and half on the west coast. Last winter the manatee population in Everglades National Park fluctuated between 100 and 200 individuals with 6 to 31 individuals observed in Florida Bay over the course of the year.
Manatees frequently migrate great distances and return to a favorite spot.
Any, or even all of the manatees found in park waters, could be in the wrong place the next time something like this occurs. This is reason for concern. These animals do not reproduce very quickly. Our focus must turn to the overall health of the natural habitat for all manatees. A healthy population is more likely to withstand future die-offs of this magnitude.