Fish Tagged For Research Become Lunch For Gray Seals

sciencehabit writes: When scientists slap an acoustic tag on a fish, they may be inadvertently helping seals find their next meal. The tags — rods a few centimeters long that give off a ping that can be detected from up to a kilometer away — are often used to follow fish for studies on their migration, hunting, or survival rates. Researchers working with 10 gray seals (Halichoerus grypus) who were captive for a year have now reported that the animals can learn to associate the pings with food. If the findings hold true in the wild, the authors warn, they could skew the results of studies trying to analyze fish survival rates or predation.