Jurisdynamic Taxon: The Florida Manatee

Thanks to the magnanimous nature of Gil Grantmore, I have been allowed to use my inaugural post to Jurisdynamics to name the West Indian manatee (Trichechus manatus latirostris) a Jurisdynamic taxon. Manatees are large, aquatic mammals whose face and body might be said to resemble an unusually elongated gray tuskless walrus with a protruding snout, smaller fins and no land capabilities. An average adult manatee measures approximately 9.8 feet in length and weighs between 800-1,200 pounds, though manatees have been known to weigh as much as 3,000 pounds. Interestingly, their closest biological relatives are two superficially dissimilar land mammals, the elephant and the hyrax. Indeed, manatees are believed to represent a unique evolutionary niche: they appear to have evolved into a solely aquatic animal from a wading, plant-eating animal. It is this unusual evolutionary connection which makes the manatee a creature of particular applicability to this blog.

The manatee is strictly herbivorous despite its girth, and a daily feeding for a manatee might consist of around 150 pounds of aquatic vegetation or, in captivity, vegetables such as lettuce and carrots. As one of the most endangered marine mammals in United States coastal waters, the manatee’s numbers are dwindling in many areas despite repopulation efforts. Manatee mortality is at its highest rate in 30 years, and only approximately 3100 manatees survive in the United States. These gentle giants have only one known “enemy” – the human. According to the Save the Manatee Club, the human danger to manatees comes in two primary variants: the negligent motorboater and the environmentally insensitive developer. However, manatees, at their peril, have also been forced to interact with still a third group of "dangerous" humans - legislators, lawyers and judges. Manatees are protected under the Endangered Species Act and are under the care of the U.S. Fish and Wildlife Services (and not the National Marine Fisheries Service like almost all other marine mammals, for better or worse). They have been the subject of federal and state litigation, and protection groups allege that quiet permits are being still given to developers in Florida to hunt them if they become inconvenient.

The manatee also appears to hold widespread crowd appeal, generating a following among technologists. A web-based open source gene evaluation and genome annotation tool carries its name. Appropriately, in the spirit of the idiosyncratic evolutionary position of the manatee, the tool allows biologists to view, modify, and store annotation for prokaryotic and eukaryotic genomes.

Manatees make nice gifts and are very friendly and petable swimming companions. The best time to go swimming with them in Florida is during the winter months when they congregate near hot springs. During the other months, they go wandering as far North as Hudson Bay, according to this article from the New York Times.

More reading is available from the Smithsonian and from Save the Manatee Club, whose spokesperson is Jimmy Buffet. The manatees pictured in this entry are Amanda and Ariel from Homosassa Springs.