This article is the second installment of a series we are writing about the many unique species of fish in the Florida Keys. At Main Attraction, we believe the more you know about the fish you are targeting, the better you will be at catching them!
Learning interesting facts about the incredible species that live in the waters of the Florida Keys helps anglers develop a greater respect for their quarry and make well-informed decisions on whether or not to keep or release a fish. This week we will learn about the Blackfin Tuna. Our Captains have been catching Blackfin Tuna for many years in the Florida Keys and their knowledge has helped us write this article. This article is a result of information gathered from their experiences and some research of publicly available information to corroborate their anecdotal evidence.
Thunnus atlanticus commonly known as Blackfin Tuna can be found throughout the western Atlantic. Blackfin is the smallest in the Tuna family reaching lengths of about 40 inches and weight of 46lbs. In the Florida Keys, we can often catch Blackfin Tuna in the 20-30lb range when the conditions are right, and our live wells are full of live bait. Our Captains know the larger Blackfin Tuna usually stay deeper in the water column while the smaller ones are closer to the surface. The technique used to catch the larger ones is to throw free swimming bait in the water to raise the schools of large Tuna near the surface and then present baited hooks. When this technique is not an option simply trolling the surface for smaller Blackfin Tuna can be very effective. You can read more about our Blackfin fishing techniques here.
The Blackfin Tuna is built for speed. They have the typical hydrodynamic streamlined tuna body that resembles a football. They can reach speeds up to 46mph and they can maintain this speed even as they are flying through the air! Tuna swim fast and eat aggressively. They feed by straining the water for smaller prey and by chasing down and engulfing larger prey. Our Captains and clients have witnessed Blackfin Tuna chasing and eating flying fish many times. Blackfin Tuna will eat a wide variety of fish and also enjoy eating squid, shrimp, and crabs. Blackfin travel in schools not only to hunt more effectively, but also as a protective measure. Blackfin Tuna are also known to travel and school with Skipjack Tuna in the Florida Keys.
From a young age, a Blackfin Tuna must learn to avoid being eaten by sea birds, Dolphinfish (Mahi), Skipjack Tuna, and even its own species. Speed is the key here, and once they are larger, they must avoid being eaten by the Blue Marlin, an apex predator capable of reaching speeds of 80mph. A freshly caught live Blackfin Tuna can be used as an irresistible bait for a large Marlin if there is one in the area. Large Sharks weighing several hundred pounds will often follow our boats as we catch Blackfin Tuna and it is not uncommon for one to get “Sharked” as a client reels it in.
Blackfin Tuna have a maximum lifespan of around 5 years. It takes them 2 years to reach sexual maturity, in comparison to the 3 months it takes a Mahi. Blackfin have been seen by both fishing Captains and researchers over the past few decades as a plentiful and sustainable food source. The Blackfin Tuna currently enjoys a conservation status that is currently of low concern and a stable population. Over the last couple of years, some Captains in Florida have observed reduced numbers in areas where the Blackfin Tuna is commonly known to frequent. This has prompted Florida Fish and Wildlife to introduce a bag limit in federal waters and to reduce the daily bag limit in state waters to 2 fish per person, or 10 fish per vessel whichever is greater. (at the time of writing this article) Main Attraction sees this as a purely preventative measure to help ensure the population remains strong in Florida for generations of anglers to come. We can see first hand there are many Blackfin tuna still out on the Marathon Humps and appreciate efforts to keep such a wonderful fishery stable. Even with the reduction in how many Blackfin boats can take on one fishing trip, that is still plenty of meat for a great day of fishing!
The Blackfin Tuna is absolutely delicious, especially eaten fresh. In the Florida keys, locals make sushi with it, or simply slice it thin and eat it raw. Fresh caught Blackfin tuna is also the main ingredient in a local favorite called Tuna Nachos. This dish consists of fried wonton wrappers topped with fresh seared tuna, and all the sushi-related fixins you might want, soy sauce, ginger, wasabi mayo, etc. Blackfin Tuna can also be smoked to make a delicious Florida Keys style Fish Dip or a tasty Tuna Fish Salad.
A good tip for Anglers to know when catching a Tuna in the Florida Keys is to bleed it out immediately upon catching it. Tuna fight hard and swim fast, when you first boat them their heart is pumping extremely fast. By cutting the main artery under their gill plates halfway between the throat and mouth the blood will pump out of the flesh quickly. This makes the meat a much higher quality for eating raw. Once the main artery is snipped with a knife or scissors the tuna should be placed in a very cold icy brine where it will bleed out. In the Florida Keys, some fishermen believe the height of flavor for raw consumption is after 3-6 hours of sitting in an icy briney bath.
If you plan to reserve a Tuna for cut bait do not bleed it out! The flesh and the gills will hold a lot of scent, which would be irresistible to many inshore predators like Tarpon and Sharks scavenging for food in the shallow waters of the Florida Keys in the mornings and evenings.