The Outer Fall area in the central Gulf of Maine is believed to be a mating ground for the endangered North Atlantic right whale, but it’s not always hospitable to humans. On a recent trip, steep swells jostled the research boat Endeavor.
The miserable conditions, though, were exactly what whale-detecting robots being tested on the voyage were built to beat.
The torpedo-shaped underwater robots, called gliders, can read calls from four types of endangered whales and relay their locations in real time. And they can do it in weather too harsh for the plane and boat surveys now used to find whales.
On a three-week trip between November and early December, the gliders developed by the Woods Hole Oceanographic Institution located nine right whales. The robots also led the Endeavor into an area where researchers were able to observe the whales firsthand, once the waters calmed.
‘‘The system worked, quite frankly, beyond my expectations,’’ said WHOI scientist Mark Baumgartner.
The gliders are primarily about protecting whales, since knowing where the whales are can help regulators devise rules that prevent fatal human contract, such as ship strikes.
The robots aren’t new, but their ability to recognize whales almost instantly is.
In 2005, they were deployed in the Gulf of Maine carrying recorders scientists needed to retrieve and listen to before they could figure out what whales the glider had found. Seven years and about $1 million later, the gliders boast a processor that so far recognizes a total of 15 of the distinctive calls made by four types of endangered baleen whales: right, fin, humpback, and sei.
A second after hearing the call, the glider identifies the whale it thinks it heard and surfaces every two hours to transmit the data, Baumgartner said.
Scientists can react to the data and direct the gliders to a wide range of locations during the five weeks they can stay at sea. That mobility is an advantage over an existing system.
The gliders can’t replace planes and boats because they can’t replace human observation. The right whales, for instance, are tracked individually, and that’s impossible without a person to identify the animals by distinctive, hardened patches of skin on their nose and jaw.
The North Atlantic right whale has a population of around 550, and no one wants to push it to extinction.