With their massive wingspans and high speed, albatrosses fly across the seas in search of food. That's why marine ornithologist Henri Weimerskirch of the French National Center for Scientific Research calls the birds the “sentinels of the sea" and is using them to survey the ocean for illegal fishing boats. Apparently, the operators of these vessels frequently turn off their automatic identification system (AIS) that broadcasts who they are and their location. From Katherine J. Wu's article in Smithsonian:
(Weimerskirch) and his colleagues have outfitted nearly 200 albatrosses with tiny GPS trackers that detect radar emissions from suspicious ships, allowing the birds to transmit the locations of fishers in the midst of illicit acts...
The range of these signals isn’t big enough to be reliably picked up by stations on shore, keeping the ships’ movements mostly discreet. Radar can be detected within a few miles of the vessel itself, however—as long as something, or someone, can get close enough...
Over the course of six months, the team’s army of albatrosses surveyed over 20 million square miles of sea. Whenever the birds came within three or so miles of a boat, their trackers logged its coordinates, then beamed them via satellite to an online database that officials could access and cross-check with AIS data. Of the 353 fishing vessels detected, a whopping 28 percent had their AIS switched off—a finding that caught Weimerskirch totally off guard.
image: "Wandering Albatross (Diomedea exulans) in flight, East of the Tasman Peninsula, Tasmania, Australia." by JJ Harrison (CC BY-SA 3.0)
