Offshore pelagic · Saltwater
Yellowfin tuna
Thunnus albacares
Native, highly migratory epipelagic tuna of tropical and subtropical oceans worldwide; in US Atlantic waters it ranges the Gulf of Mexico, southeastern Caribbean, and up the coast, moving across entire ocean basins. Purely oceanic, not landlocked or introduced.
Also called ahi.
- Offshore
- Regulated context
- 4 of 4 overlays reviewed
- Reviewed 2026-08-27
Before you target this fish
Regulated context — check the rules for the exact water
Where this applies Atlantic Highly Migratory Species (HMS) fishery, US Atlantic and Gulf of Mexico state and federal waters, managed under the 2006 Consolidated Atlantic HMS FMP and internationally by ICCAT.
The reviewed context, unedited
Vessels must hold a valid HMS Angling or HMS Charterboat/Headboat permit to fish for Atlantic yellowfin (and bigeye, albacore, or skipjack) tuna. Recreational minimum size is 27 in curved fork length (jaw tip to tail fork), with a bag limit of 3 fish per person per day/trip. Yellowfin cannot be retained if a hammerhead or oceanic whitetip shark is aboard or has been offloaded from the vessel. The 2024 ICCAT-informed stock assessment found Atlantic yellowfin not overfished and not subject to overfishing. Confirm current size, bag limit, and permit requirements before fishing.
Rules for this fish change at a state line and sometimes inside one. Check the ones that apply to the exact water you are standing on before you act on anything here — this record is biology, not permission.
Take this somewhere
This page is the record. The reading is what happens when you add water, a season and a temperature to it — that is where the families below get ranked against each other instead of just listed.
Those three links carry the fish and nothing else. No conditions were declared on this page, so none travel, and the link says so rather than sending an empty reading.
The half nobody publishes
What this record does not know
Everything else on this page comes from a named agency or peer-reviewed source. This is the other side of that: the questions a reviewer went looking for an answer to and came back without, and the fields the record leaves empty because filling them would mean guessing.
It is here rather than at the bottom because a page that only shows what it knows is easy to read as a page that knows everything. For Yellowfin tuna there are 12 of them.
Named by a reviewer
9Somebody looked for this and wrote down that they did not find it.
- Behaviour
The tagging study's diel-depth and thermal-preference figures come from one specific tagged population; a broader cross-population synthesis was not found.
Cold-front / barometric-pressure response with primary-source support.
Angling-pressure response with primary-source support.
- Identification
A single average-adult-length or typical-weight figure was not found in the acceptable sources reviewed; only the maximum size (about 400 lb) and minimum legal size (27 in CFL) are sourced.
Distinguishing traits from blackfin tuna, a smaller Western Atlantic lookalike commonly encountered alongside yellowfin, were not sourced in this review and are omitted rather than guessed.
- Forage
A quantified prey-species breakdown (e.g. specific baitfish or squid species) for the western Atlantic population was not found.
Seasonal or ontogenetic diet-shift detail beyond the juvenile mixed-schooling note was not found.
- Season
A month-by-month US Atlantic/Gulf recreational-fishery presence calendar was not found; only spawning-window timing and thermal/current-feature preference are sourced.
Winter habitat use/behavior was not specifically sourced for the western Atlantic population.
Absent from the record
3No reviewer wrote a gap here. The field is simply empty, which is its own answer.
- Water temperature
No agency or peer-reviewed temperature band for Yellowfin tuna was found that a review would accept. The reading runs without one rather than borrowing a number from a related fish.
- Identification
No reviewed image. A photograph is only in this catalog when an agency or a named creator labelled the subject, and nobody has cleared one for this species yet.
- Population context
No regional population profile is registered. The species-level reading stands on its own; it does not silently become a local one.
Where the record puts it
Water and range
Offshore
3 reviewed holding classes- Temperature break
- Current rip
- Open-water bait school
DepthStays mostly within the surface mixed layer: one peer-reviewed tagging study found tagged fish spent 97.6% of their time above 200 m, with a mean daytime depth around 74 m and a somewhat deeper mean nighttime depth around 94 m in that study population. Vertical movement is close to fully inhibited once water temperature drops below about 46°F (8°C).
Moving waterOceanic and highly mobile; a peer-reviewed habitat-suitability study found higher yellowfin habitat suitability associated with mesoscale eddies and current fronts, particularly warm-core (anticyclonic) eddy margins, where convergence concentrates prey and eddy-driven downwelling carries warm, oxygen-rich water to depth.
LightDiel vertical pattern documented by tagging: daytime and nighttime depth distributions track the deep scattering layer (roughly 40-100 m), consistent with feeding on the same vertically migrating prey layer both day and night, with somewhat deeper mean depths recorded at night in the reviewed study population.
Thermal band
Temperature
No reviewed temperature band
Nobody publishes a preferred or active temperature range for Yellowfin tuna that a review would accept. Borrowing one from a related fish would look like knowledge and behave like a guess, so the reading runs without it and says which parts of the answer that weakens.
How it uses water
Behaviour
A schooling pelagic species throughout its life history, not a solitary hunter.
An apex-level predator feeding on fish, squid, and crustaceans; peer-reviewed tagging found feeding patterns tracking the vertical migration of the deep scattering layer (roughly 40-100 m) both day and night. Diet capacity is not evidence of a current bait event.
Active both day and night, with a documented diel depth shift: mean daytime depth around 74 m versus a somewhat deeper mean nighttime depth around 94 m in one tagged population, following the deep scattering layer's migration rather than resting at night.
Temperature-driven behaviourPeer-reviewed tracking found the majority (about 71%) of horizontal movement occurring between 79-82°F (26-28°C), with a broader optimal/preferred range cited as roughly 68-84°F (20-29°C). Vertical movement becomes almost completely inhibited once water temperature drops below about 46°F (8°C), and tagged fish have dived into water as cold as about 39-41°F (4-5°C) on brief excursions -- a tolerance limit, not a preference.
Depth movementSpends the large majority of time (97.6% in one tagged population) above 200 m, within the surface mixed layer; briefly dives much deeper (in excess of 1,000 m in one recorded case) into water below 46°F, where vertical movement is sharply reduced.
Facing the currentHigher habitat suitability is associated with mesoscale current fronts and eddies, especially warm-core (anticyclonic) eddy margins, where convergence concentrates prey; one study also found seasonal use of cooler, nutrient-rich cyclonic-eddy water in summer, consistent with following productivity rather than temperature alone.
Spawning (conservation context)Batch spawner (roughly once every 3 days through the season) once mature at age 2-3, releasing 1-4 million eggs per event. Western Atlantic spawning timing differs by region: May-August in the Gulf of Mexico, July-November in the southeastern Caribbean (broad ocean-basin regions, not named sites). Spawning water and any staging concentration are conservation context only and are not described as holding water.
Where the general rule stops
- Retention is prohibited on any trip where a hammerhead or oceanic whitetip shark is aboard or has been offloaded -- a vessel-level rule, not a size or season rule, and easy to overlook.
What it can eat
Forage
- Small forage fish
- Larger prey fish
- Crustaceans
- Mollusks
An apex-level pelagic predator feeding on fish, squid, and crustaceans near the top of the food chain; peer-reviewed tagging found feeding activity consistent with tracking the deep scattering layer's vertical migration both day and night. Diet capacity is not evidence of a current bait event.
- Feeding style
- Opportunistic
- Feeding zone
- Pelagic
By life stage
- Young of year
- Juveniles school with skipjack and juvenile bigeye tuna, consistent with feeding on similarly small pelagic prey.
- Adult
- Adults feed on fish, squid, and crustaceans, with feeding activity tracking vertically migrating prey layers.
Diet capacity is not proof that a bait event is happening now; observed current forage still comes from a direct sighting, not from this dossier.
Through the year
Season
Early summer
- Where they sit
- Offshore water at mesoscale current fronts and warm-core eddy margins within the preferred thermal band.
- Temperature
- Within or approaching the roughly 79-82°F band associated with the majority of horizontal movement in reviewed tracking data.
What would count against it
- Assuming a fixed regional arrival date; a sourced calendar for this was not found.
Gulf of Mexico spawning season (May-August per NOAA) is underway; spawning water is excluded from holding-water guidance.
Summer
- Where they sit
- Offshore water at current fronts and eddy margins; one peer-reviewed study found seasonal use of cooler, nutrient-rich cyclonic-eddy water in summer alongside the warm-core eddy association.
What that changesChum-established drift and live-bait slow troll at a located current seam or temperature break; trolling spread to search open water between features.
What would count against it
- Treating a single day's surface activity as proof of sustained local abundance.
Gulf of Mexico spawning season continues (through August per NOAA); southeastern Caribbean spawning begins in July. Spawning water is excluded from holding-water guidance.
Fall
- Where they sit
- Offshore water at current fronts and eddy margins within the active thermal band.
What would count against it
- Assuming continued Gulf of Mexico spawning-related aggregation after the May-August window without a supporting source.
Southeastern Caribbean spawning continues into November per NOAA; spawning water is excluded from holding-water guidance.
Spawning · Early summer, Summer, Late summer, Fall
Batch spawner (spawns roughly once every 3 days through the season), releasing 1-4 million eggs per spawning event once mature (age 2-3). Western Atlantic spawning timing differs by region: NOAA gives May-August in the Gulf of Mexico and July-November in the southeastern Caribbean (broad ocean-basin regions, not named sites). Spawning water and any staging concentration are conservation context only, not holding water.
Recorded as conservation context. No spawning site, staging concentration or migration bottleneck is named anywhere in this catalog, because naming one is how a population gets fished out.
Telling it apart
Identification
What to look at
- Long, bright yellow second dorsal fin and anal fin, with a yellow stripe running down the side.
- Finlets are bright yellow with no black edging (versus bigeye tuna's yellowish finlets edged with a fine black line).
- Pectoral fins are short, thick, stiff, and blade-like, reaching only to about the base of the second dorsal fin (versus bigeye's longer, thinner, flexible pectoral fin that extends past that point).
- Body outline is elongated and narrow with a straight tail, versus bigeye tuna's deeper, thicker, rounded body outline.
- Fresh coloration shows a bright yellow mid-lateral band with a thin blue separation from the dark back; color fades quickly after death and should not be the only field mark relied on.
- Average adult length
- Not resolved to a single figure in reviewed sources; see gaps.
- Common angling size
- Recreational minimum retention size is 27 in curved fork length under Atlantic HMS rules; landed sizes above that vary widely by region and season.
- Typical weight
- Not resolved to a single typical-weight figure in reviewed sources; see gaps.
- Maximum documented
- Grows to up to about 400 lb.
- Longevity
- A comparatively short-lived tuna, with a lifespan of about 7 years.
What it gets confused with
- Bigeye tuna (Thunnus obesus)
- Bigeye tuna have finlets edged with a fine black line (yellowfin's are unmarked yellow), longer and more flexible pectoral fins extending past the second dorsal fin base, and a deeper, more rounded body outline than yellowfin's straight-tailed, elongated shape.
What follows from all of that
Presentation families
Offshore
Chum-established drift
Establish a scent trail and drift baits back through it at the speed the current is already moving.
- consistent trail
- unweighted or lightly weighted drop-back
- match the sink to the drift
- do not outpace the trail
What it asks of the tackle
- Depth control
- Low
- Sensitivity
- High
- Casting distance
- None
- Weight range
- Unweighted to 2 oz
- Cover resistance
- Low
- Line visibility
- Low
- Retie frequency
- Moderate
Live-bait slow troll
Move live bait just fast enough to cover water while it still swims naturally.
- barely-moving speed
- bait leads the boat
- let it swim
- drop back on a follow
What it asks of the tackle
- Depth control
- Moderate
- Sensitivity
- High
- Casting distance
- None
- Weight range
- Unweighted to 4 oz
- Cover resistance
- Low
- Line visibility
- Low
- Retie frequency
- Moderate
Trolling spread
Pull several baits at different distances and depths so one crosses a fish travelling through open water.
- stagger the spread
- match speed to the bait
- work the edge, not the middle
- turn on marks
What it asks of the tackle
- Depth control
- Moderate
- Sensitivity
- Low
- Casting distance
- None
- Weight range
- Trolling weights and heads
- Cover resistance
- Low
- Line visibility
- Secondary
- Retie frequency
- Low
Vertical jig
Work a compact bait up and down through a marked depth, basin, or timber pocket.
- stay over the target
- measured lift
- controlled drop
- watch slack
What it asks of the tackle
- Depth control
- High
- Sensitivity
- High
- Casting distance
- Vertical
- Weight range
- 1/8–3/4 oz
- Cover resistance
- Moderate
- Line visibility
- Low
- Retie frequency
- Moderate
What moves them for this fish
Reviewed rules that push particular families up when the conditions match. Each one names the conditions it needs and why it exists, so you can disagree with it.
Yellowfin habitat suitability is highest at mesoscale current fronts and eddy margins where convergence concentrates prey, so once a boat is on that seam, holding a scent trail or slow-trolled bait there fits better than continuing to search.
When
Offshore · Temperature break, Current rip
Moves up
Chum-established drift, Live-bait slow troll, Trolling spread
Reviewed 2026-08-30
Tagged yellowfin track the vertical migration of the deep scattering layer both day and night, feeding on that same prey band, so working a marked bait concentration through its depth fits better than a family with no depth control.
When
Offshore · Open-water bait school
Moves up
Vertical jig, Live-bait slow troll
Reviewed 2026-08-30
Where every sentence came from
Sources
Agency
NOAA Fisheries, Atlantic Yellowfin Tuna species page
Used for habitat, thermal band and presentation families; identification; behaviour; forage; season. Read 2026-08-30, next check 2026-11-27.
Agency
NOAA Fisheries, Atlantic Bigeye, Albacore, Yellowfin and Skipjack Tuna Recreational regulations
Used for habitat, thermal band and presentation families; identification. Read 2026-08-30, next check 2026-11-27.
Peer reviewed
Habitat and behaviour of adult yellowfin tuna (Thunnus albacares), Aquatic Living Resources
Used for habitat, thermal band and presentation families; behaviour; forage. Read 2026-08-30, next check 2026-11-27.
Peer reviewed
Mesoscale activity drives the habitat suitability of yellowfin tuna, Scientific Reports
Used for habitat, thermal band and presentation families; behaviour; season. Read 2026-08-30, next check 2026-11-27.
Synthesis
ISSF handbook for identification of yellowfin and bigeye tuna
Used for identification. Read 2026-08-30, next check 2026-12-13.
A source with no link predates the rule that one has to carry a URL. It is still a real citation and still checkable; it just takes a search rather than a click, and that is worth knowing before you rely on it.