Marlin, black and blue, caught in hot water

STATEWIDE — Three marlins weighing almost 1,500 pounds combined and caught off the San Diego coastline in a one-month span received a fair share of media attention in September and October. Warmer waters meant more marlin being caught in local waters. What best practices should anglers be aware of whenever a billfish is biting at the other end of the line? A marine life scientist and game fish conservationist provided some perspectives of how everyone can enjoy marlin fishing without depleting the species.

Black-and-Blue Battles

An angler recently shared photos of marlin brought into Oceanside, joining a growing list of billfish captured within U.S. waters and weighed in at shore. The marlin hauled into Oceanside late last month reportedly weighed 510 pounds. Another angler weighed his marlin catch at Shelter Island in San Diego in late September; it tipped the scale at 662.2 pounds. A third marlin was caught on Oct. 13 near the 9 Mile Bank and reportedly weighed-in at 315 pounds. Total weight: 1,487 pounds.

At least two of the anglers said the marlin they caught could not be released, what with one already dead when it was reeled aboard and the other, in his judgment, on the verge of flat-lining.

“The 500- to 600-pound marlin often survives just fine if the correct (heavy) tackle is used,” said Alayna Siddall, a science director at Sportfishing Association of California. “The most damage is done when they are fought on light gear and handled too long for photographs. The larger the marlin the more important it is to get the fish released quickly.”

Jason Schratwieser, the International Game Fish Association’s (IGFA) conservation director, said marlin might die after a long fight but the billfish can be quite resilient.

“After a long fight marlin may sometimes die but just because the fish has faded coloration and is sluggish doesn’t mean it’s a gonner,” Schratwieser said.

He shared a story of a marlin caught in a tournament and left for dead that actually survived.

“Years ago in a tournament we caught a marlin that came up completely brown in color and the captain declared it a dead fish. The mate and I thought otherwise and spent 10 minutes reviving the fish by slowly moving the boat forward so that water could run over the marlin’s gills,” Schratwieser said. “In a few minutes time, the fish’s color came back and it began to beat its tail. We tagged that fish with a satellite tag that reported that the fish survived for over 100 days until the tag popped off.”

Using the right type of bait and tackle and making an effort to revive caught marlin could help save the fish species, Schratwieser added

“In general minimizing fight time, using circle hooks with bait and taking the time to revive exhausted fish are some of the best things you can do,” Schratwieser said.

Both Schratwieser and Siddall say El Niño conditions contributed to the existence of marlin in U.S. waters.

“Most marlins are tropical species and the warm waters associated with El Niño have allowed blue marlin (especially) to expand their range temporarily into southern California waters,” Schratwieser said.

Low Abundance of Marlin

Worldwide marlin populations are low, spawning federal legislation to protect billfish. IGFA initiated a billfish preservation program called “Take Marlin Off The Menu” while The Billfish Foundation advocates marlin conservation with an annual International Tag and Release Competition.

Schratwieser testified about marlin stock assessments before the House Natural Resources Subcommittee on Fisheries during deliberation of the Billfish Conservation Act, which was signed into law by Pres. Barack Obama in 2012 and prohibits commercially caught billfish (marlin, sailfish and spearfish) from being imported into the United States.

“Marlin stocks worldwide are not faring well due to commercial overfishing,” Schratwieser told The Log. “Most stocks that have been adequately assessed are either in an overfished condition and/or experiencing overfishing. Some species such as black marlin, spearfish and Pacific sailfish have never even had formal assessments so their health is unknown.”


Every marlin battle is unique. There is no hard-and-fast way to ensure all anglers fully enjoy the pursuit of a marlin before releasing the billfish into the water.

Both IGFA and The Billfish Foundation actively promote anglers using proper catch-and-release techniques with caught marlin.

A caught marlin, when properly handled, have a high chance of survival when released, according to Siddall.

“Catch-and-release is usually the best option when it comes to marlin. These are long-lived, beautiful species that we want to have the opportunity to catch for generations to come,” said Siddall, who studied fisheries at Scripps Institution of Oceanography. “We know that when striped marlin are caught and handled properly, fisheries research has shown that they generally have high survival, so the best option is catch-and-release whenever possible.”

Schratwieser said a vast majority of marlin released by recreational anglers continue navigating the ocean.

“Catch-and-release recreational fishing poses little threat to marlin populations. Studies have demonstrated 85 percent or more of marlin caught by recreational anglers survive,” Schratwieser said.

The Marlin Club in San Diego reported 32 marlins were caught by recreational anglers between July 31 and Sept. 26; 23 of them were released.

A Fighting Chance to Survive

How a marlin is caught influences its chances of surviving upon release. The position of the marlin in relative position to the boat and how long the billfish is held in water are vital factors to survivability.

“Striped marlin sometimes appear non-releasable, but if you give them a chance they usually swim away just fine. The most important thing is to hold the fish alongside the boat by the bill, leave the body completely in the water, remove the hook or jig, hold it in the water for 10-20 seconds if necessary to revive while the boat moves forward at very slow speeds, and then let go and let the fish swim away,” Siddall said. “Another important thing is to use a rod, reel and line class heavy enough to bring the fish to the boat as quickly as possible.”

Anglers battling marlin for hours or photographing the catch for extended amount of time negatively impact the billfish’s chances of surviving a catch.

“Long fight times, poor handling and taking too much time for photographs all lead to high post-release mortality, especially on bigger marlin such as large stripers, as well as blues and blacks,” Siddall said. “However, marlin can recover from lengthy battles, so the best thing to do is to give the fish the benefit of the doubt, and release the fish.”

Looking Ahead

What steps are currently being taken to formally protect marlin?

“The short answer is not nearly enough,” Schratwieser said. 

“The U.S. has taken a big leadership role to protect billfish. Commercial harvest and sale of Atlantic billfish has been banned since 1989 and commercial long-line vessels have to use circle hooks which helps increase the survival of marlin that are caught and released,” Schratwieser said. “Recreational anglers fishing billfish tournaments in the Atlantic also have to use circle hooks, which dramatically cuts down on post release mortality.”

Enactment of the Billfish Conservation Act of 2012 also helped but more work still needs to be done, Schratwieser added.

“Unfortunately, marlin is a highly migratory species that frequently cross oceans and boarders,” Schratwieser said. “As such, strong international conservation measures are needed to ensure that these species don’t decline further.”

Conserving black and blue marlin in U.S and Mexico waters means more anglers will have the opportunity to experience billfish action, Siddall added.

“We hope everyone gets a chance to get on the water and experience catching these amazing fish,” she said.

Leave a Reply

Your email address will not be published. Required fields are marked *