Fishing

Study contains good news for bluefin tuna

 

Research shows that using different fishing gear could eliminate the bycatch of bluefin tuna in their Gulf spawning grounds.

scocking@MiamiHerald.com

A research scientist at Nova Southeastern University Oceanographic Center is in the home stretch of a pilot study showing that substituting two types of fishing gear for pelagic long-lines might eliminate the bycatch of severely overfished bluefin tuna in their northern Gulf of Mexico spawning grounds.

The preliminary findings of David Kerstetter and several graduate students are important because bluefins are the priciest and most exploited fish. Their stocks have plunged over the past several decades despite strict international management measures. The northern Gulf is one of a few spots where bluefins are known to reproduce, and many are caught accidentally by commercial long-line fishermen targeting yellowfin tuna and swordfish. To make matters worse, the 2010 BP oil spill might have taken out large numbers of bluefin larvae because it occurred in the middle of the spawning season.

Kerstetter, who has extensive experience with the commercial buoy gear fishery for swordfish in southeast Florida, wanted to find out whether substituting that equipment — as well as commercial “greenstick” gear — for miles of baited surface hooks in the Gulf would result in less bycatch of bluefins and other species such as sea turtles and billfish. So, for the past year, he and several graduate students have been working with four commercial fishing boats to switch from long-lines in the Gulf.

Buoy gear consists of a floating, lit-up marker attached to a mainline with one or two branch lines, each with a baited hook. When a fish strikes, it pulls the buoy across the surface, alerting the fishermen to retrieve it. Greenstick gear consists of a pole mounted amidships trolling a mainline behind the boat that holds five to 10 “drop lines” baited with plastic squid that skip across the surface. When a fish bites the baits, the mainline breaks away from the greenstick and is retrieved by a hydraulic winch. Both systems are tended immediately when a fish hits, while pelagic long-lines have up to 40 miles of baited hooks dangling just beneath the surface that might not be hauled back until long after hooked fish or other species are dead.

After 150 fishing days beginning in March 2012 using greenstick equipment to target yellowfins and buoy gear for swords, Kerstetter said his group observed more than 16,000 pounds of yellowfin and more than 3,000 pounds of swordfish landed — without a single catch of bluefin tuna, sea turtles or marine mammals. Small numbers of other species were caught — including wahoo, dolphin, blackfin tuna, white marlin and blue marlin — with nearly all released alive, Kerstetter said.

The preliminary findings from the study, which will go on for several more months, emerge as NOAA Fisheries is poised to propose a rule to reduce bluefin tuna bycatch.

Kerstetter says it might be possible for commercial fishers to make more money catching fewer fish using the alternative gear.

“You don’t need as much crew, or boat or gear,” he said. “You can land fewer fish and make the same or more money doing it because the product quality is higher.”

Read more Outdoors stories from the Miami Herald

  •  
 <span class="cutline_leadin">Timing:</span> West Palm Beach resident Kacie Herrick, 29, finished last year’s Boston Marathon about 40 minutes before the first bomb went off.

    Boston Marathon

    South Florida runners return to Boston for emotional marathon

    In what is sure to be an emotional day, several locals are back in Boston to finish, or finish how they wanted to last year before terrorists struck.

  •  
Steve Kantner prepares to release a grass carp estimated at 12-14 pounds that he caught on fly rod in the C-11 canal in Davie.

    OUTDOORS

    Flyfishing for carp a ‘berry’ good time

    Fort Lauderdale author and fly fisherman Steve Kantner idled slowly west on the grassy, linear park swale between Orange Drive and Griffin Road in Davie on a recent weekday afternoon, examining the broad, leafy ficus trees lining the banks of the C-11 canal.

  • Notebook

    Measures by Wildlife Commission target invasive lionfish

    The Florida Fish and Wildlife Conservation Commission, meeting last week near Tallahassee, stepped up the battle against the spread of invasive lionfish. Commissioners gave preliminary approval to draft rules that would prohibit importation and development of aquaculture of lionfish; permit divers using rebreathers to harvest the venomous exotics; and expand opportunities for spearfishing tournaments to target lionfish.

Get your Miami Heat Fan Gear!

Join the
Discussion

The Miami Herald is pleased to provide this opportunity to share information, experiences and observations about what's in the news. Some of the comments may be reprinted elsewhere on the site or in the newspaper. We encourage lively, open debate on the issues of the day, and ask that you refrain from profanity, hate speech, personal comments and remarks that are off point. Thank you for taking the time to offer your thoughts.

The Miami Herald uses Facebook's commenting system. You need to log in with a Facebook account in order to comment. If you have questions about commenting with your Facebook account, click here.

Have a news tip? You can send it anonymously. Click here to send us your tip - or - consider joining the Public Insight Network and become a source for The Miami Herald and el Nuevo Herald.

Hide Comments

This affects comments on all stories.

Cancel OK

  • Marketplace

Today's Circulars

  • Quick Job Search

Enter Keyword(s) Enter City Select a State Select a Category