Mysterious, New Ailment Kills Manatees off of Florida Coast

A red tide has swept near southwest Florida, killing a record number of manatees and other marine animals. Yet it's not only this algal bloom that has affected the manatee population. State biologists have also found that a mysterious ailment is wiping out these gentle giants.

Red tides are famed for their destructive qualities. They're caused by blooms of the algae, Karenia brevis, and are named "red tides" for the distinctive red-brown hue that they give to ocean waters. The algae produce neurotoxins which are deadly to fish, sea turtles, birds, marine mammals and even humans if they consume enough fish or breathe enough of the toxins in the air.

Yet now, a new ailment has affected manatees off of Florida's east coast. Since last July, about 55 manatees have died of similar symptoms in the Indian River Lagoon area with about half of them perishing in just the last month. Despite the efforts of biologists, though, officials have been unable to determine what the cause is.

Manatees are currently endangered. Slow-moving animals that frequent the warm waters around Florida, they were once hunted for their hides, oil and bones. Because of this, their numbers have declined drastically over the past century. However, they are now a protected species; unfortunately, these sea cows face other threats.

Could it be a red tide? Most likely it isn't. There is currently no red tide bloom on the East Coast. In addition, the winter hasn't been very cold, which rules out temperature as being a factor for killing off more than a few manatees.

Instead, biologists suspect that the manatee deaths are connected to back-to-back blooms of a different kind of harmful algae that has stained the Indian River Lagoon a brownish color. This new kind of algae has wiped out about 31,000 acres of sea grass--a primary food source for manatees.

So far, no sick manatees have been recovered, and most of them don't appear to have starved. Instead, it seems that many of the mammals have gone into shock and drowned after eating algae. It's possible that with the lack of sea grass to eat, the animals have turned to less healthful sources of food.

Currently, more investigation is needed to determine the exact cause of death. Yet with manatees facing pressures from boats, habitat destruction and fishing nets, they will need all the help they can get.