Although whalers may no longer be a major threat to the animals’ survival, right whale populations continue to be decimated by encounters with ships in overly trafficked waters. In fact, collisions between the two now account for nearly 1/3 of all reported whale deaths according to biologist Regina Asmutis-Siver of the Massachusetts based Whale & Dolphin Conservation Society. This is especially frightening when you realize that only 500 right whales remain in the wild.
While human whale watchers have traditionally been employed to keep a lookout for the behemoths and warn ships of their approach so they can (hopefully) avoid contact, the method is far from reliable.
“They may be the size of a school bus, weighing 40-80 tons, but spotting whales in the vastness of the open oceans is like trying to find a needle in a haystack,” commented Mark Baumgartner of the Woods Hole Oceanographic Institute. As a result, WHOI has begun using a pair of 6-foot long, torpedo-shaped robot gliders to locate the whales by listening to them “sing” in the Bay of Fundy between Maine, New Brunswick and Nova Scotia.
The gliders first record the sounds the whales, then use the information to create a spectrogram, which is almost like virtual sheet music that visually represent what it’s hearing, which is then transmitted to shore-based computers so that the scientists can quickly map out the whales’ location while they are still within range. Once they are located, they can then notify ships to reduce their speed and proceed with caution.
While high tech listening buoys perform similar duties in the shipping lanes that run through the Stellwagen Bank National Marine Sanctuary near Boston, the new gliders have the advantage of being mobile (rather than stationary) and can continue to travel and transmit the sounds every two hours for 4-5 weeks on end before their batteries need recharging. Another advantage is that these underwater robots are also equipped with a wide range of environmental sensors that record temperatures and salinity in the marine areas, and estimate algae population levels that can provide scientists with a “crude sense of how much zooplankton the whales are feeding on in each location.
“As a result, the gliders have an enormous capacity to not only help us understand where the whales are, but why they are there,” exclaimed Baumgartner.
For a related article see http://www.examiner.com/article/whales-to-be-given-right-of-way-san-fran...