Ringing the dinner bell.
Researchers often use sound-emitting tags to keep track of fish, but are these devices drawing in predators? According to a study recently published in The Proceedings of the Royal Society B, acoustic fish tags may serve as a “dinner bell” to predators like grey seals. The study, which was conducted by researchers at the University of St. Andrews in Scotland, suggests that grey seals naturally hone in on the “pings” emitted by these tags, which could prove not only detrimental to the fish, but also impact the research that tags are being used for.
“Research agencies worldwide invest significant resources in acoustic tagging studies to assess fish stocks and determine survival rates,” the study stated. “As acoustic tags could make a fish more vulnerable to predation, tagging can lead to erroneous conclusions in such studies.”
In their experiment, researchers set up a maze of 20 foraging boxes in a pool. Half of these boxes contained a fish with a tag and the other half a fish with no tag. The researchers then let 10 seals into the maze and found that the predators consistently visited the boxes with a tag more than those without.