Identifying the Yellowfin Tuna

Catching Yellowfin Tuna

Yellowfin tuna are well known for their physical beauty and powerful swimming, however, the similar appearance across the different varieties of tunas can lead to some confusion over identification. The albacore, bigeye, bluefin and yellowfin tuna are all football shaped and have a streamline body with shimmers of silver on their sides and darker colorations by their dorsal. The yellowfin has a dark blue dorsal surface while it can appear brownish in the water. True to their name, the yellowfin tuna have yellow in their fins and a shiny, golden yellow along their sides but coloration alone won’t allow you to correctly identify the different species of tuna. A key feature to identify a yellowfin tuna is the length of their pectoral fins. Each species has a particular “design” to their pectoral fins that identifies them: The yellowfin’s pectoral fin reaches the beginning of their second dorsal fin while the albacore pectoral fin always goes beyond the start of the second dorsal and the bluefin pectoral fin never reaches the second dorsal fin. The combination of color and pectoral fin size should give you a clear identification in most cases.

Size of the Yellowfin

Yellowfin tuna grow faster than the bluefin tuna, but do not reach the large size of their giant cousin. The largest yellowfin tuna on record was 388 lbs. And was caught in Mexico in 1977. The growing cycle for a yellowfin tuna 8-10 pounds at one year, age 2 about 35 lbs. and at 3 years old about 75 pounds. By 4 years old a yellowfin will averages about 130 lbs and can on average get as large as 200 lbs.

Angling and Handling Tips

Yellowfin tuna are one of the most challenging species to catch with a rod and reel during your tuna fishing charter. Their large size and high capacity for exercise can result in broken tackle if you are poorly prepared. Trolling and chumming are the primary methods used by anglers, but there are many tips for catching Yellowfin Tuna. Trolling involves creating a flashy presentation of multiple lures trolled in the boat wake while moving along at 7-8 nautical miles per hour. Single hook lures with plastic skirts are a common offering and chains or spreader bars of lures are an option to increase the visual attraction. Green is a popular color for yellowfin tuna. The idea is to have a pattern of lures that splash, wiggle and sparkle enough to trick the fish into thinking it is attacking a group of agitated baitfish. Chumming involves introducing a baited hook to yellowfin tuna while the boat is drifting or anchored. Cut pieces of common bait fish are tossed in the water around the baited hook to attract tuna.

Tackle Needed

Both methods use similar fishing tackle. Yellowfin typically range between 30-80 pounds, so use high quality 30, 50, or 80 pound-class reels, rods and line to fish for these beauties. Yellowfin that exceed 100 pounds are matched well with the 80 pound class gear. Lighter tackle can be used and is gaining popularity, but you better be prepared for a fight if you want to land a 150 lb. yellowfin tuna with 30 pound class tackle. Once you’ve hooked a yellowfin, rods are transferred to the angler wearing a gimbal belt and/or back harness. This allows for a “stand-up” fish fighting technique. A good position for an experienced angler but one that can quickly fatigue an inexperienced angler faced with a large tuna. The excitement generated in the cockpit as multiple yellowfin tuna strike and rip line off the reels is the highlight of sport fishing for yellowfin tuna.

Catching Yellowfin is Exciting

Tunas will fight to the end to get away so, if you are planning to release your catch, keep the fish in the water if possible while you remove the hook. Try to avoid bruising or cutting the tuna during boat side handling. If the tuna is fatigued, swim the fish along for a few minutes while the boat is in gear to allow the fish to “catch its breath” (release carbon dioxide and make up oxygen debt). If you’re planning to boat the tuna, be sure to bleed and chill the fish as soon as possible. Fresh yellowfin is a delight to eat and a 40 pound fish can feed a lot of people. Raw Yellowfin doesn’t have the same reputation as bluefin tuna sashimi, but don’t pass it up if you like sashimi. And marinated yellowfin steaks on the grill are a fantastic.

Louisiana’s Yellowfin Tuna

Yellowfin tuna is an abundant tropical tuna found throughout the Gulf of Mexico but caught most often off the shores of Louisiana. Yellowfin tuna are considered a single species in all oceans. However, the relationships between distinct seasonal aggregations of yellowfin within ocean basins are not well described. In the western Atlantic Ocean, fisheries have developed to target aggregations of yellowfin tuna in the Gulf of Mexico, Caribbean Sea, and along the Continental Shelf and slope waters from Hatteras to Cape Cod. Much larger harvests occur at fishing grounds in the east Atlantic. Yellowfin are exposed to fisheries in Massachusetts only off the south side of Cape Cod, where seasonal warming and Gulf Stream influences allow yellowfin to range over the Continental Shelf to forage during the summer.

So with yellowfin tuna fisheries around the world what makes the Louisiana’s yellowfin fishery so unique? Well just about everything, from environment to tuna behavior.

North America’s largest river flows out against Gulf Stream eddies (the Loop Current), and these currents meet above deep nearshore canyons along a shelf margin that is littered with FADs (oil rigs). Yellowfin tuna recreational catches out of Louisiana on a day charter fishing trip can, at times, resemble what you’d see on a Pacific long-range tuna trip off Mexico.

But one thing that really stands out is the lengthy season: You can catch yellowfin tuna off southeast Louisiana all year. Whether anglers are live-bait fishing with pogie fish, chumming by shrimp boats or natural bottom features, or throwing topwater lures near surface-feeding whale sharks, there’s always action available.

Clues about the yellowfin tuna’s life history in the Gulf of Mexico tell their story from adults in spawning condition, day-old larvae caught during surveys, juvenile tunas just months old, and multiyear tag returns from adults recaptured in almost the exact same area they were released. The data suggests that some yellowfin tuna might spend a whole lifetime in the Gulf of Mexico. Perhaps not the picture you’d expect for a highly migratory species?

In response to the importance of the Gulf of Mexico yellowfin tuna to Louisiana-based user groups and the lack of biological information, the Louisiana Department of Wildlife and Fisheries (LDWF) began a comprehensive yellowfin-research program.

Tagging Tuna

A light stalk of the tag protruding from the tuna’s abdomen and a green-and-white conventional tag near the dorsal fin are what tells a sport fisherman that the tuna he just caught has a computer in its belly. The type of tagging operation being done by the LDWF in the Gulf of Mexico requires that these fish be re-caught and reported for the data to be recovered from the tag. And while a 2 percent recapture rate might not justify a large investment in an internal-tagging project, LDWF biologists knew that the local recapture rate was closer to 10 percent based on conventional tags deployed on yellowfin as part of the Louisiana Cooperative Fish Tagging Program. So based on the hope of a slightly higher recapture rate in the region and that offering a $200 gift-card reward would incentivize participation, LDWF began tagging yellowfin in 2013 with internal and pop-off satellite tags in the north-central Gulf. For a more detailed understanding of the tagging process for the yellowfin tuna in the Gulf of Mexico check out the article by Brett Falterman, Program Manager at LDWF.

Recreational Fishery Regulations

Both the recreational and commercial fisheries for yellowfin tuna are regulated by the National Marine Fisheries Service (NMFS). Click here for more information, or call 1-888-USA-TUNA.