Are Slow Boats Bigger Threat for Grazing Sea Cows?
Guess what, boaters? A researcher at Florida Atlantic University says that motoring slowly through designated manatee protection habitats may put the meandering sea cows at greater risk of getting hacked up by your boat's motor. Says Dr. Edmund Gerstein, the university's director of marine mammal behavioral research: "In turbid waters where there is no visibility, slow speeds actually exacerbate the risks of collisions by making these boats inaudible to manatees and increasing the time it takes for a boat to now travel through manatee habitats."
Sounds like 20 years of laws forcing boaters to drive slowly through manatee zones might have done more harm than good. Oops!
You see, unlike dolphins -- which use sonar to navigate -- manatees rely on their passive listening skills to get around. But boats mostly emit low frequency sounds that manatees have trouble hearing. That explains why after being hit once (and in some cases 50 times), the animal doesn't know to get out of the way the next time. They can't see OR hear our darn boats. Last year, boats killed 73 manatees in Florida bays and inland waterways.
Good ole Dr. Gerstein has a solution for this problem. He has been testing an alarm that emits a high-frequency signal at a NASA wildlife refuge. And he's happy to report that each and every time a boat approaches a manatee with the alarm sounding, the manatee scoots away. For comparison, without the alarm, the manatees only tried to avoid the boat 3% of time. Ouch!
Manatees aren't the only mammals prone to collisions with boats for auditory reasons. Apparently ocean freighters frequently take out great whales in the open seas.
So what are you waiting for, Dr. Gerstein? Get those mammal alarms on the market already!-- Amy Guthrie