Researchers have found a new way to decrease the number of hammerhead sharks accidentally killed by longline fishing gear.
Hammerhead shark populations have declined by about 89 percent over the last two decades, primarily due to illegal poaching and accidental bycatch.
Scientists have determined that creating a mild electric field around fishing lines can be successful at keeping some sharks–specifically sharks that use electrically sensitive organs, like the hammerhead–away from the lines.
They create this electric field by attaching rare-earth lanthanide metals (neodymium and praseodymium) to the fishing fear instead of lead weights. The only problem with this method is that lanthanide metals dissolve fairly quickly in water and they are expensive.
The good news is that according to the new study, test lines in Hawaii caught less than half as many scalloped hammerhead pups as lines that didn’t have a surrounding electric field.
To learn more
- Find the full study, published in the journal Fisheries Research, here: The effects of a lanthanide metal alloy on shark catch rates
Copyright © 2012 by Marine Science Today, a publication of Marine Science Today LLC.