Galeocerdo cuvier · Galeocerdonidae · predator
One of the largest predatory sharks, with a short snout and dark stripes that fade with age. In Brazil it is not a threatened species, but the right thing is to release it: it grows slowly and has few pups per year.
Also called: tubarão-tigre, tintureira, jaguara, cação-tigre
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.
Reading the weather across 3 global models and 31 simulations…
Each card shows the day's index (0 to 100) and, below it, a strip with the index for each hour, from 0h to 23h. from poor to excellent.
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.
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.
The tiger shark lives in tropical and temperate seas worldwide, over the continental shelf, around oceanic islands, reefs and estuary mouths, and makes forays into open sea. In Brazil it occurs along the whole coast, especially in the Northeast, where it has been studied for decades because of the incidents at Recife. It hunts mostly at night and eats almost anything: fish, other sharks, rays, turtles, birds, squid and even trash. It exceeds 5 m and hundreds of kilograms. In sport fishing it appears on deep bottom boat trips with large baits and in catch-and-release tournaments in the Caribbean and Mexico. It is not on the national list of threatened species, but its global assessment is Near Threatened: what matters for the angler is a short fight and release in the water.
Very short, wide snout, almost square from above, huge mouth. Gray to brown back with dark vertical bars and spots, strong in juveniles and faded in large adults. Tail with a long, pointed upper lobe and a low keel on the caudal peduncle. Wide, serrated teeth, shaped like a rooster's comb. The bull shark also has a short snout, but it is plain gray without stripes, and has a taller first dorsal fin.
Along the whole Brazilian coast, most common from the Northeast to the Southeast and at oceanic islands such as Fernando de Noronha. In the western Atlantic it ranges from the USA to Uruguay, including the Caribbean and the Gulf of Mexico; in the Pacific, from California to Peru.
Habitat: Continental shelf, reefs, shoals, oceanic islands, estuary mouths and ports; makes forays into open sea.
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
Estimate: it occurs year-round in the tropics. In Recife, a long-term study recorded more tiger sharks near the coast from January to March and from June to September, with a drop from October.
Night and twilight. Hunts mostly at night and at dusk; by day it usually stays deeper and farther from the beach.
Warm-water species: in water below about 20 °C it becomes less active and moves away.
Little direct effect.
Dark nights and new-moon nights tend to be the busiest near the coast.
Turbid rain water attracts prey to river mouths; the tiger hunts well in dirty water.
Not applicable at sea.
Not very sensitive; it often follows boats and the smell of fish.
Rough seas hinder bottom boat fishing.
Spring tides move prey at estuary mouths and reef channels.
From the surface to about 140 m most of the time; it can go down to hundreds of meters.
natural baits
accessories
Fishing for release only. With a circle hook, don't set the hook: let the line tighten. Bring the shark alongside the boat as fast as possible, without bringing it aboard, and cut the cable close to the mouth if the hook is deep. Never fish for shark from a beach where there are bathers.
Summary of the regulations we found, with the source for each. Rules change; before keeping or transporting fish, check with the state environmental agency.
Conservation: Not on the national list (Portaria GM/MMA 1.667/2026). Global assessment: Near Threatened (IUCN, Aug 10, 2018). The general rules of recreational fishing and the finning ban apply.
In Brazil, finning is prohibited (cutting off the fins and discarding the body). Every shark or ray landed must arrive with its fins attached to the body; it is prohibited to carry on board an animal without fins or with loose fins, and to transfer sharks between vessels. It applies to any shark that may be kept.
In recreational sport fishing in Mexican saltwaters, the limit for sharks is one specimen per angler per day, which counts as five toward the total limit of ten fish. Fish caught in sport fishing may not be sold. Catch and release does not count toward the limit: prefer releasing.
In 2021 Colombia stopped considering sharks and marine rays a fishery resource and began treating them as a hydrobiological resource; the recitals of Decree 281/2021 state that they may not be extracted for commercial or sport purposes, and the decree created an environmental protection plan. Later AUNAP rules dealt with incidental catch in artisanal fishing; we did not check the consolidated text. When in doubt, release it into the water.
Do not lift it out of the water or drag it on the sand: the weight of the body injures the organs. Short fight; release it alongside the boat with the shark in the water and cut the cable close to the mouth if the hook cannot be removed. Never put your hand near the mouth or hold it by the gills.
Not recommended: large sharks accumulate mercury in their flesh, and the 'cação' sold in Brazil mixes threatened species. Release it.
Length-weight relationship W = a·Lb (a = 0.00724, b = 3.09; FishBase (estimativa bayesiana para a família e o formato do corpo, comprimento total)). It's an average: a fat or lean fish can vary by 10% to 20%.
estimated weight
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The seasonal weights (months), time of day and 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 field experience of anglers and guides. The months indicate the time of year when the angler usually finds the species near the coast, not a catch season. They are not official data or measurements made for this species and may vary by region and year. Legal rules appear in the rules section, with the regulation and link.
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.
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:
Your location is saved only on this device and feeds the forecast, the map and the "today" on the home page.
