Blackfin Tuna (Thunnus atlanticus) aren’t as popular as their blue and yellow-finned kin but are a fun fish to fight and a pretty tasty fish to put on the table. Since their meat doesn’t keep for a long time, they’re not usually found on restaurant menus. So the best way to taste the lean meat of a bluefin tuna is to catch it yourself. This article will help you recognize this fish, find where it lives, choose the right bait and lures, and decide which tasty recipe to try. Let’s get into the world of fishing blackfin!
What is a Blackfin Tuna?
With so many types of tuna out there, how can you tell which is which? Of course, most anglers will be happy with a tuna on the line, regardless of which species it is. But, when you really enjoy the fight of a blackfin, it helps to know how to repeat the experience. Also, some species have restrictions, depending on where you’re fishing. It’s always good to know what you’ve got so you aren’t caught unaware by the authorities. Blackfin have several easy to find features that help distinguish it from the crowd.
Blackfin are the smallest in the Thunnini family, a group of fish that includes albacore, yellowfin, and bluefin. Their average length is about three feet and their average weight is 45 pounds. They have the typical torpedo-shaped body of their close relatives, with little bronze finlets that run from the dorsal and anal fins back to the tail. Along their upper body, they have a dark, almost black stripe that fades into a yellow-brown stripe at the midpoint. The belly is silvery gray, sometimes iridescent. Some of this coloration, especially the more colorful areas, fades when the fish dies. The tailfin is shaped like a crescent. Their mouths point upward and the eyes rest behind the tip of the nose. Their small scales cover the entire body.
They spawn off the Florida coast beginning in April and continuing through most of the year. In the Gulf of Mexico, the spawning period is a little shorter, lasting from June through September. They like to do their spawning in the deep water off the coasts of Florida and Brazil. Blackfin spawn multiple times during the season. The females can lay upwards of 500,000 eggs each time she spawns. Females can start to spawn when they reach 19 inches and males when they reach about 21 inches long. If they don’t get eaten by a marlin, a dolphinfish, or a skipjack, they can live to age five and beyond. Aside from their underwater predators, blackfin tuna are also eaten by seabirds like terns, frigate birds, and wedge-tailed shearwaters.
For a comparison of the different tuna fishes, check out Fish Anywhere.
Where to Find a Blackfin Tuna
As the old saying goes, there are a lot of fish in the sea. They don’t exactly post their whereabouts on Facebook either. Honestly, that would probably take some of the fun out of fishing. For many anglers, the hunt is more satisfying than the catch. Local guides and boat operators are generally good sources of info when searching for a specific type of fish. Lots of tech exists that will help you penetrate the surface of the water and locate schools of fish too. But, even with those resources, you’ll have to know where to start. Here are some tips on finding blackfin tuna.
Blackfin is an Atlantic marine fish that occupy a large swath of water from Massachusetts all the way down to Rio de Janeiro. These fish move around a lot, performing long migrations throughout their range as the weather changes. Warm weather will draw them away from the equator, cold weather will bring them closer. The direction will change depending on which hemisphere they’re in, which makes the equator a good reference point. They’re normally found past the Continental Shelf on the seaward side. Blackfin prefers clean waters at around 70 degrees.
Following the bait is always a good rule when it comes to carnivorous fish and blackfin chasing is no exception. Although they don’t hang around structures on their own, they’ll head over to them to find food. Their diet of shrimp, crabs, and squid means they frequent areas with a lot of these creatures about. Following a shrimp boat is a great strategy that saves you a lot of time. Let them spend their money on tech! A shrimp boat is a lot easier to spot than the shrimp are. Bluefin know this trick too, so they hang out behind these boats to snap up the leftovers. Oil rigs are another highly visible place where the bluefin’s prey congregate.
Barring either of those options, reefs and floating jetsam can be great places to find bluefin. They’ll feed all up and down the water column, sometimes at depths of 1,000 feet. But, they’re a shy fish, so they don’t spend time at the surface during the daytime unless it’s an overcast day. Look for them at the surface in the early morning and after dusk. During the brightest parts of the day, they’ll be in the lower depths.
For Florida-specific blackfin tuna tips, see this Sport Fishing Magazine article.
Best Bait for Blackfin Tuna
Blackfin tuna will go after live bait far more often than cut bait or lures. When fishing blackfin with live bait, it’s a good idea to use what the fish are already eating in whatever area you’re in. Their diet doesn’t vary much with the region, since they go where the food is, but there might be something that’s working particularly well for anglers in a certain spot. Talk to the locals to see what’s working. These fish eat smaller fish, shrimp, crabs, amphipods (shell-less crustaceans), and stomatopods (mantis shrimp). If you’ve ever fished skipjack, the blackfin feed right alongside them, sometimes in mixed schools. You can also have success with ballyhoo, herring, minnows, or bonito strips dressed with fluorescent hula skirts or trolling feathers.
Trolling is the most common blackfin tuna fishing method and a lot of anglers lay out a chum slick to bring them near the boat. You don’t want to satisfy the fish’s hunger with chum though, so keep the pieces small. Think of it as an appetizer for what’s on your hook. A chum grinder will help get the pieces the right size. You can get one on Amazon for under a hundred bucks. Chumming and chunking are more effective in the early morning and at dusk, rather than in the heat of the day. Once you’ve stirred up their appetite, it’s time to start dropping your bait.
Using an outrigger, keep your speed around eight knots. You want your bait to sink down in the water, so higher speeds will require you to add sinkers or weight to your line. Plus, if you’re churning up a lot of white water, these relatively shy fish will be unlikely to get near the boat. A spinning rod is your best option as far as rods go. Add about 40 feet of light fluorocarbon leader and a small hook. 1/0 and 3/0 sized hooks work great. Your main line should be a 20-pound fluoro.
One important note on fishing bluefin in Florida: In July of 2019, the Florida Fish and Wildlife Conservation Commission voted to create a recreational limit on blackfin catches. While there’s no size limit to the fish you can keep, the catch limit is two per person or 10 per boat, depending on which is higher. You do not need a federal permit for blackfin.
For more on Florida’s recreational limits, check out this Billfish article.
Best Lures for Blackfin Tuna
If you don’t want to deal with the mess and hassle of live bait, some lures work well too. Generally, anything that mimics a small, shiny baitfish is good or go for squid-like sparkly lures. Bring a variety of lures out with you and experiment to see what the fish are biting on that day. Keep in mind also that bluefin tuna lures will attract other types of tuna and game fish too, so be prepared to fight a bigger fish than you bargained for.
A few specific suggestions for hard lures: A Berkley Cutter 90+ in black silver or Skeletor Vapor colors; a Shimano Topwater Orca in clear silver, or a MirrOlure She Pup in chrome/blue black are all solid. These are the shiniest color options, but all but the Shimano come in a variety, so you can match the hatch.
If you want to try soft baits, go for Berkley’s Gulp! Alive! Minnow, the Savage Gear Swim Squid, or this Squidy soft lure from Walmart. For some tuna-specific skirts, look for the JAW Tuna Buster in blue silver or UV green, the Williamson Tuna Catcher Kit, or the Islander Flasher series in chrome w/blue/white or chrome w/pink/white colors.
Best Recipes for Blackfin Tuna
Depending on where it’s caught, blackfin tuna can be eaten right out of the water. It’s a popular sashimi fish. However, it doesn’t store for long, so you’ll need to eat it as soon as possible. The flavor is similar to other tuna, but bluefin is lean, so a lot of the fatty flavors in other fish will be absent here.
Once caught, you need to bleed it and ice it right away. Make a deep incision underneath both pectoral fins. Then, either cut off the tail or cut a ring around it. Stand the fish up on its head and let it bleed out. Once that’s done, store the fish in an ice/saltwater bath until you get to the kitchen. Cleaning a blackfin is just like a yellowfin or bluefin.
Now that you’ve cleaned up your catch, it’s time to decide how to cook it or not cook it. Table and Hearth has a great recipe for Soy Lime Blackfin Tuna Ceviche if you want to go the raw route. If you’ve never had ceviche before, it’s pretty amazing and really brings out the flavor of the fish in a way the cooking does not. Technically, ceviche isn’t raw, the acidity of the citrus juices cures the fish and changes its texture. If you’re nervous about preparing ceviche yourself, try this Barbecue Seared Blackfin Tuna recipe from Suwannee Rose. It includes an avocado sauce and slices of fresh mango. Yum!
Regardless of how you fish it or prepare it, blackfin is great fun to catch and delicious to eat. It’s often under-appreciated among the tuna fishes, but it’s worth going after. Be safe, good luck, and have fun!
Also, check out: How to Catch a Mackerel