the right time
to be on the water
Choose the place and the species. The index, from 0 to 100, combines weather, sun, moon and tide with each fish's habits. Up to 28 days, with each day's confidence.
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hour by hour
slide your finger or mouse over the chart to see each hoursee hour-by-hour table
why this index at —?
choose the day
the fishing month at a glance
what's the best window for the crew?
Choose how many fishing days. We compare each stretch by its average index, discount days with a warning or closed season, and show the 3 best.
trend for the coming weeks
Line: the middle value of 31 simulations of the American GEFS model. Band: where 8 out of 10 fall. Narrow, firm trend; wide, high uncertainty.
everything about the bigeye tuna
how to recognize it
Robust, torpedo-shaped body, dark metallic blue back, iridescent blue stripe along the flank of the live fish, and whitish belly. Large eye. First dorsal fin dark yellow, second dorsal and anal fins pale yellow, finlets bright yellow with a black edge. In adults, moderately long pectorals; in juveniles, as long as those of the white albacore but with a rounded tip. Differs from the adult yellowfin tuna by the absence of yellow sickle-shaped fins and by its larger eye.
Also called: albacora-bandolim, bandolim, patudo, albacora-olho-grande, atum-cachorra
don't confuse with:
where found
open on the large mapWhere to look: Open sea and slope; adults below the thermocline by day, near the surface at night; juveniles in schools around floating objects.
Open sea along the whole coast, over the slope and beyond.
coast
states
Amapá, Pará, Maranhão, Piauí, Ceará, Rio Grande do Norte, Paraíba, Pernambuco, Alagoas, Sergipe, Bahia, Espírito Santo, Rio de Janeiro, São Paulo, Paraná, Santa Catarina, Rio Grande do Sul
famous destinations
when to fish
best season
Present all year in open sea; recreational fishing depends on the sea and on associated schools.
best time of day
Dawn and dusk. Rises late in the afternoon and at night; by day it stays deep, within reach only of heavy jigs.
what affects the bigeye tuna
cold and cold fronts
Lives in cold water below the thermocline; surface cold matters little.
atmospheric pressure
A cold front brings rough seas.
moon
Full-moon nights change the depth at which it hunts.
rain
Not very sensitive.
water level
Follows the thermocline and the fronts.
noise
Not very sensitive in open sea.
wind
Rough seas prevent going out.
tide
No significant tide in the ocean; current is what matters.
depth
50 to 400 m by day; shallower at night.
how to fish
lures
- 200 to 400 g jigs
- large lipped plugs
- silicone squid
natural baits
- whole squid
- live bait (bonito, mackerel)
tip from an angler
On platforms and fishing boats, respect the safety zones and fish drifting on the outside; work the jig at the depth the sonar shows.
- rod
- stand-up 50 to 80 lb; jigging PE 5 to 8
- spinning / baitcasting reel
- 50 to 80 lb trolling baitcaster or 14000 to 20000 spinning reel
- line
- braided PE 5 to 8 or monofilament 50 to 80 lb
- leader
- fluorocarbon 100 to 150 lb, 2 to 3 m
- hook
- circle 9/0 to 12/0; assist hooks 7/0 to 9/0
accessories
- fighting belt and harness
- bicheiro
- luvas
catch and release
A long fight wears the tuna out a lot: if you are going to release it, shorten the fight, don't lift it out of the water, and release it with the boat moving, head first.
rules for the bigeye tuna
Rules change; before keeping or transporting fish, check with the state environmental agency.
We found no species-specific rule beyond the region's general rules.
Conservation: Not on the national list (Portaria GM/MMA 1.667/2026); the category is the IUCN global assessment (VU, 2021). The Atlantic stock is managed by ICCAT. We have not found a federal minimum size for recreational fishing. IUCN global: VU · vulnerable.
how much it weighs without taking it out of the water
estimated weight
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how we calculate
Length-weight relationship W = a·Lb (a = 0.01318, b = 3.03; FishBase (estimativa bayesiana, comprimento total)). It's an average: a fat or lean fish can vary by 10% to 20%.
more about the bigeye tuna
The bigeye tuna, or albacora-bandolim (patudo), is a large tuna of tropical and subtropical oceans, with big eyes adapted to low light. Adults spend the day in deep, cold waters below the thermocline and rise to near the surface at night; juveniles form schools at the surface, alone or mixed with yellowfin tuna and skipjack tuna, often around floating objects. It eats fish, squid, and crustaceans, by day and by night. The fatty flesh is among the most prized for sashimi. In Brazil it is caught by pelagic longline and, now and then, in recreational offshore jigging and trolling. The Atlantic stock is managed by ICCAT, and the species is Vulnerable in the IUCN global assessment.
Family: Scombridae · predator
fun facts
- The big eye is an adaptation for hunting in low light, below the thermocline.
- Can exceed 2 m and 200 kg.
in the kitchen
Red, fatty flesh, among the most prized for sashimi; bleed and chill it quickly.
similar species
sources and references (8)
The season weights (months), the time of day and the sensitivities (cold, pressure, moon, wind, rain, tide, strong light, murky water and noise) are the app's editorial estimates, based on the literature below and on the field experience of anglers and guides. They are not official data nor a measurement made for this species, and they may vary by region and year. Closed seasons and legal rules appear in the rules section, with the norm and a link.
- scientific FishBase — Thunnus obesus (ficha da espécie)Names, distribution, biology, length-weight relationship and references. Page checked on October 13, 2026.
- official Portaria GM/MMA nº 1.667, de 27 de abril de 2026 — Lista Nacional Oficial de Espécies da Fauna Ameaçadas de Extinção (peixes e invertebrados aquáticos)Most recent national list. The species is not on it (search by scientific name in the text published in the DOU, checked on October 13, 2026).
- official ICMBio/SALVE — Ficha de Thunnus obesus (avaliação nacional do risco de extinção)ICMBio national assessment, published in 2025. DOI checked on Crossref.
- scientific IUCN Red List — Thunnus obesus (avaliação global: Vulnerável, VU, 15/01/2021)Global assessment. Link given on the FishBase entry (Red List, version 2025-2).
- scientific Collette, B. B.; Nauen, C. E. (1983). FAO species catalogue. Vol. 2. Scombrids of the world. FAO Fisheries Synopsis 125(2). Roma: FAO.
- technical ICCAT Manual, cap. 2.1.2 — Bigeye tuna (Thunnus obesus). International Commission for the Conservation of Atlantic Tunas.Biology and fishery of the species in the Atlantic.
- scientific Carpenter, K. E. (org.) (2002). The living marine resources of the Western Central Atlantic. Vol. 3: Bony fishes part 2 (Opistognathidae to Molidae). FAO Species Identification Guide for Fishery Purposes. Roma: FAO.Scombridae chapter (Collette, B. B.), cited by FishBase for the species.
- scientific Figueiredo, J. L.; Menezes, N. A. (2000). Manual de peixes marinhos do sudeste do Brasil. VI. Teleostei (5). São Paulo: Museu de Zoologia da USP. 116 p.Printed work; the URL is the bibliographic record on FishBase, which cites this work for the species.
how we calculatewhere each number comes from
The weather comes from three independent global models, cross-checked hour by hour: when they agree, confidence goes up; when they diverge, the band between them shows on the chart. Beyond 16 days, we use the GEFS ensemble of 31 simulations: if 20 of the 31 predict rain, the chance of rain is 65%. Sun and moon are calculated astronomically, with no uncertainty.
The index adds up, weighted for each species: time of day (species curve anchored to real sunrise and sunset), moon (transits, rise and set, phase), pressure (3 h trend and 24 h swing), water temperature (in rivers, estimated from air temperature; at sea, estimated by an ocean model), wind, rain, clouds, tide and the month in the species' cycle.
sources for this lookup
how accurate the forecast is
Accuracy measured in the reference project (4 regions, 93 days, forecast vs. observed): maximum temperature is off by 0.6 °C on average the next day and 1.7 °C at 7 days; rain of 5 mm or more is detected 76% of the time the next day and 57% at 7 days. Detection isn't everything: the false alarm rate isn't published here yet, and 93 days in 4 regions is still a small sample. We now also measure every day, at the app's destinations: