Carcharhinus altimus · Carcharhinidae · predator
Robust, grey shark of the shelf edge and upper slope, rare in shallow water. Near Threatened worldwide; it appears in deep bottom fishing in the Caribbean and the eastern Pacific.
Also called: tubarão-narigudo, bignose shark, tiburón baboso, tiburón narizón, Knopp's shark
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 bignose shark is a heavy, cylindrical-bodied shark that reaches 3 m and nearly 170 kg. It lives near the edge of continental and island shelves and on the upper slope, usually at 80 to 220 m, but has been recorded from 12 to 810 m. Rare in shallow water, it stays near the bottom at shelf breaks and walls, and juveniles may appear at 25 m. It eats bony fish, other sharks, rays and cuttlefish. The female gives birth in alternate years, with 1 to 13 pups (average 9). It is caught incidentally and for fishmeal, liver oil and leather. FishBase lists it as a sport fish, but it is rare on the line. The FishBase country list does not include Brazil.
Cylindrical, heavy-bodied shark, grey with no visible marks and white below. Large, long, broad snout with long nasal flaps. Tall, well-marked ridge between the dorsal fins; large, straight dorsal and pectoral fins, with the inner corner of the pectorals darkened. Upper teeth triangular and serrated. It resembles the barriga-d'água (C. plumbeus) and the dusky shark (C. obscurus), both protected in Brazil. The tall ridge between the dorsal fins and the broad snout are clues, but confirmation requires a trained eye: when in doubt, release it.
Circumglobal, in tropical to temperate waters of the Atlantic, Pacific and Indian oceans. The FishBase country list does not include Brazil. Caught in the Caribbean (Cuba, the Bahamas, Trinidad and Tobago, Venezuela, Colombia, Nicaragua, Panama, Mexico) and in the eastern Pacific (Costa Rica, Ecuador, Peru).
Habitat: Edge of continental and island shelves and upper slope, near the bottom at breaks and walls; juveniles may appear at 25 m.
Estimate: present year-round in deep waters; FishBase cites births in August and September in the Mediterranean and in September and October off Madagascar.
Any time. Lives deep, usually 80 to 220 m, where daylight matters little; no defined time (estimate).
Not very sensitive: lives where the water is colder and more stable.
Little known direct effect.
Little known effect.
No effect in deep water.
Not applicable at sea.
Not very sensitive to noise at the surface.
Rough seas make it hard to keep the boat over the deep fishing spot.
Strong current moves the baits and may attract the shark.
Usually 80 to 220 m; recorded from 12 to 810 m.
natural baits
accessories
It comes up from the bottom exhausted: release it quickly, with the animal in the water. Check the ridge between the dorsal fins and the snout: it looks almost identical to other grey sharks protected in Brazil, such as the barriga-d'água and the dusky shark; when in doubt, release it.
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: IUCN global assessment: NT (A2d, 14/02/2020). Does not occur in Brazil according to the FishBase country list; Brazilian rules apply if it is hooked in Brazilian waters.
In Brazil, finning is banned: catching sharks and rays and keeping only the fins, discarding the body (art. 3). Sharks and rays landed must arrive with all fins naturally attached to the body; carrying an animal aboard without fins or with loose fins, and transferring sharks and rays between fishing vessels, is prohibited. This applies to any species that may be retained.
In recreational sport fishing in Mexican marine waters, the limit for sharks is one fish per angler per day, which counts as five toward the total limit of ten fish (item 4.9.1 b). Fish over the limit must be returned alive to the water (item 4.9.5), and recreational catch may not be sold (item 4.11). Fish that are released do not count toward the limit: prefer to release it.
In 2021 Colombia stopped treating marine sharks and rays as fishery resources and began treating them as hydrobiological resources. 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 addressed incidental catch in artisanal fishing; we did not check the consolidated text. When in doubt, release them into the water.
Executive Decree 9/2026 (art. 19) bans, throughout the national territory and in sport, recreational, or tourism fishing, the catch, retention, handling for recreational purposes, use, and landing of sharks and rays (subclass Elasmobranchii). If one is hooked by accident, it must be released immediately, without taking it fully out of the water and without unnecessary handling. It is also prohibited to promote them as targets in tournaments (art. 19) and to sell the catch (art. 20). The decree takes effect six months after its promulgation on June 10, 2026 (art. 40), around Dec 10, 2026, and repeals Resuelto ADM/ARAP 002/2012 (art. 39). Confirm the date with ARAP.
The official fishing guide of the Bahamas states that shark fishing is not allowed, that sharks have been protected since a 2011 amendment, that they may only be taken under special permits for very specific purposes, and that a shark hooked in any fishing must be released unharmed. The page does not cite the number of the rule.
Keep the fight short and release with the shark in the water. Cut the wire leader flush with the mouth if the hook is deep; a barbless circle hook often releases on its own. Do not hold it by the gills or tail, and revive it facing into the current before letting go.
Used for fishmeal, liver oil and leather (FishBase). Sharks retain urea in their flesh: bleed and gut it quickly. As it is Near Threatened and is confused with protected species, prefer to release it.
Length-weight relationship W = a·Lb (a = 0.00372, b = 3.08; FishBase (relação peso-comprimento bayesiana, estimativa da própria espécie)). It's an average: a fat or lean fish can vary by 10% to 20%.
estimated weight
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The season factors (months), the time of day, and the sensitivities (cold, pressure, moon, wind, rain, tide, strong light, murky water, and noise) are editorial estimates by the app, based on the literature cited below and on field experience of anglers and guides. They are not official data or measurements made for this species and may vary by region and year. Closed seasons and legal rules appear in the rules section, with the standard and link. The months indicate when anglers usually find the species near the coast, not a catch season.
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.
