http://www.sciencemag.org/news/2020/01/seabird-cops-spy-sneaky-fishing-vessels

Researchers used wandering albatrosses like these to find fishing boats that may have been avoiding detection.

Sometimes fishing vessels vanish: Captains turn off beacons that broadcast their locations, leaving regulators wondering whether the boats are fishing illegally. Now, researchers have shown that albatrosses bearing small radar detectors can find these suspicious vessels—even in the middle of the open ocean. After a 6-month study with the large seabirds, the researchers estimate that more than one-third of vessels in the southern Indian Ocean are sailing undercover, confirming concerns about illegal or unreported fishing.