Not all of man's activities are great for the manatee, of course, and recreational boating is among the most problematic. Manatees generally float just beneath the surface of the water, making them vulnerable to collisions with boat hulls and propellers, which account for about a quarter of manatee deaths every year. Manatees have recently been reclassified in Florida as a "threatened," rather than "endangered" species, causing concern among conservationists who argue that the manatee's slow rate of reproduction still can't keep up with the rate of human-related and natural deaths that happen every year.
The final cool fact, with a great sound effect that follows: Most of the long bones in a manatee's body, particularly the rib bones, do not produce marrow and as a result are very dense. Scientists believe these heavy bones act as ballast for the manatee...but why would such a big critter need that extra weight? One theory is that their all-veggie diet fills them up with a lot of gas, which could cause them to be overly buoyant (remember they like to float just under the surface, or sometimes even hang out on the bottom), so the dense bones balance that out. And all that gas does, eventually, have to come out.
With that thought, the final sound clip, courtesy of the Save the Manatee Club, whose very cool website has lots of other fun facts about the manatee. Be sure to play it to the very end!
Article by Sarah Horton.
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