Silky and oceanic whitetip shark populations are heavily depleted in the Western and Central Pacific Ocean. It was thought that much of the population decline was due to bycatch in commercial longlines. A new study from the Secretariat of the Pacific Community (SPC), however, reveals that these sharks aren’t being caught accidentally; some fishermen are specifically targeting them.
Dr. Shelton Harley, Principal Fisheries Scientist in SPC’s Oceanic Fisheries Program, explained that these results were both unexpected and exciting.
“We knew that almost all the longline catch of these species was caught by boats targeting tuna but, when we analyzed the data collected by independent Pacific Island fisheries observers, we discovered that a lot of the sharks were being caught on special lines with wire traces and shark bait attached to the floats on the longlines,” Dr. Harley said in a news release. “In fact, these lines took up to half of all silky and oceanic whitetip sharks captured on the observed longline trips.”
These special shark lines are not only catching silky and oceanic whitetips, but other species of concern, such as hammerhead and tiger sharks.
The good news is that this problem is more easily solved than if population decline was due to bycatch alone. A statement from the Pacific Islands Forum Fisheries Agency (FAA) Deputy Director-General Wez Norris notes that “if it was accidental bycatch then it might be a difficult problem to solve, but here we see that the main problem is these appropriately named ‘shark-lines’.”
The FFA will call for a ban of these shark lines at the Western and Central Pacific Fisheries Commission meeting this coming December.
To learn more:
- Read the full news release: The best way to protect heavily depleted shark populations? Stop trying to catch them!
- Check out this short piece from Radio New Zealand: Sharks targeted, not bycatch.
Copyright © 2014 by Marine Science Today, a publication of Marine Science Today LLC.