Species › Global · Open Ocean & Worldwide › Blackfin Tuna

Saltwater

Blackfin Tuna

Thunnus atlanticus · Blackfin, Football tuna, Bermuda tuna

Water temp
72–82°F
Peak season
Mar–May, Nov–Dec
Best light
Daytime
IGFA record
50 lb 1 oz (22.71 kg)
Blackfin Tuna (Thunnus atlanticus 215085116.jpg)

Photo: Ryan Watson · CC BY 4.0 · via Wikimedia Commons

OverviewWhere & WhenHow to CatchGearRegulationsRecordsForecastCatches

Overview

Blackfin tuna have a dark blue-black back, a gold or bronze band along the side, dusky finlets with little or no yellow, and relatively long pectoral fins. Most weigh 5 to 20 lb and the largest approach 50 lb. They are a western Atlantic species found from Massachusetts to Brazil, including the Gulf of Mexico and Caribbean, with the heaviest concentrations around the Florida Keys, the Bahamas, Venezuela and the Louisiana oil rigs.

Blackfin feed on small fish, squid and crustaceans, often crashing bait at the surface at dawn and dusk and mixing with skipjack and small yellowfin. They hold on humps, shelf drop-offs, wrecks and rigs where current piles up bait. Marathon and Islamorada's offshore humps are the classic fishery and have produced every recent record. For anglers without a long-range boat, blackfin deliver a genuine tuna fight on 20–30 lb gear, and few fish top them for sashimi.

Typical size5–20 lb (2–9 kg); 20–30 in
Trophy30 lb+; 40 lb+ is a potential record
Table fareExcellent — dark red meat ideal for sashimi, poke and searing

How to catch

Live-baiting the humpsAnchor or drift up-current of a hump and fish live pilchards, threadfins or ballyhoo on 5/0 circle hooks and 40 lb fluorocarbon, either free-lined or on a light kite. Chum with live bait to pull the school to the surface, then feed a hooked bait into the frenzy.
Vertical jiggingDrop 60–150 g speed or slow-pitch jigs to the bottom of the marked bait and rip them back at high speed. Blackfin usually hit within the first 20 cranks. Use a short, parabolic jigging rod and 30–40 lb braid.
Trolling small feathers and plugsPull 4–6 inch feathers, cedar plugs and small skirted lures at 6–8 knots along color changes and rips, with a couple set far back on a long-rigger line. A bird teaser ahead of the lure improves hookups on spooky fish.
Chunking at nightAround Gulf rigs and under lights, drift cut sardine or bonito chunks in a steady chum line and free-spool a hooked chunk back with the slick. Let the fish run before engaging the reel; a 3/0–5/0 circle hook does the rest.

Gear

Rod7' medium-heavy spinning or 5'6"–6' jigging rod, 20–40 lb class
Reel5000–8000 spinning or 20–30 lb class lever drag
Line30–40 lb braid with a 30–50 lb fluorocarbon leader

Lures

Metal speed jigsSmall skirted trolling luresCedar plugsFeather jigsTopwater poppers for surface schools

Baits

Live pilchardsThreadfin herringBallyhooCut bonito or sardine chunksSquid

Regulations

US anglers need a state saltwater license, and a federal HMS angling permit is required to fish for any Atlantic tuna from a private boat. Blackfin have no federal size or bag limit at present but some states set their own, so check before keeping a limit.

Records

IGFA all-tackle world record: 50 lb 1 oz (22.71 kg) — Off Miami, Florida, 2024 (Robert Kowalski). State and regional records are kept by each fish & wildlife agency.

Frequently asked

How do you tell a blackfin tuna from a small yellowfin?

Look at the finlets: blackfin finlets are dusky with at most a faint yellow tinge, while yellowfin finlets are bright yellow with black edges. Blackfin also show a bronze or gold band along the side and have a darker, almost black back. Yellowfin grow far larger, so anything over 50 lb is not a blackfin.

What is the best time to catch blackfin tuna in the Florida Keys?

Late fall through spring, roughly November to May, when cooler water concentrates bait on the Marathon and Islamorada humps. Dawn is prime, with fish busting on the surface for the first hour of light, and a strong east-flowing current on the humps turns the bite on at any time of day.

Bite forecast — Blackfin Tuna

Recent catches

Posted by anglers on the live map, filtered to Blackfin Tuna.

Pin: