September 11, 2023 — Students at the University of New England are studying how low-level electrical impulses might be used to repel sharks, a method they hope will protect fishermen’s valuable catch as well as the sharks that too often die trying to steal it.
If the concept proves itself in the field, the students hope to develop a long-lasting, affordable device that recreational and commercial fishermen can add to their lines to stop shark bycatch without hurting their chances at reeling in a halibut in the waters off Maine, or a tuna off Hawaii.
“Fishermen see sharks as a nuisance,” said junior Clayton Nyiri, a marine science major who is running the recreational fishing side of the project. “They’ll steal your bait and, if they can, your fish, too. They’ll swallow the hook whole, so you have to replace it. … All that trouble, but no commercial value.”
The National Oceanic and Atmospheric Administration and National Sea Grant College Program fund research projects like this to protect the economic value of lucrative fisheries, and to protect shark species that are vulnerable to overfishing in part because they are often inadvertently caught by commercial fishermen.
Since 1970, the number of oceanic sharks and rays has declined by 71% because of an 18-fold increase in fishing pressure, including both targeted and accidental catches, putting three-quarters of the species at risk of global extinction, according to a 2021 study by an international team of shark researchers.
Pelagic longliners, which can suspend thousands of individual fishing lines and baited hooks off a main fishing line that can run for miles behind a boat, pose a bycatch threat to several kinds of overfished Atlantic sharks, including scalloped hammerhead, dusky, sandbar and blacknose.