Oligosarcus jenynsii · Acestrorhamphidae · predator
The branca is a large-toothed fish of the rivers and lagoons of Rio Grande do Sul, also present in Uruguay and Argentina. It eats other fish and is mainly of commercial use.
Also called: branca, lambari-bocarra, saicanga, tambica, dientudo, pike characin
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 branca is of the family Acestrorhamphidae and reaches 31 cm, weighing up to 330 g. It lives in streams, rivers and lagoons of the coastal areas and interior plains of Rio Grande do Sul, as well as Uruguay and Argentina. It is a freshwater fish that moves within rivers and feeds on other fish. It is part of the region's commercial fishing, but rarely shows up on the line of rod anglers.
Essential profile. Identification, where it occurs and rules, with data from FishBase and the cited regulations. Season, time of day, technique and bait are added once we have a good source for the pike characin (branca); in the meantime, see the similar species.
Spindle-shaped, silvery body with a large mouth and teeth showing, as the Spanish name dientudo indicates. It reaches 31 cm and is a fish predator, which sets it apart from the lambari-do-rabo-vermelho (Psalidodon fasciatus), which has a red tail, is much smaller (up to 17 cm) and also eats meat and other foods.
In Rio Grande do Sul, in coastal areas and the interior, also occurring in Uruguay and Argentina.
Habitat: Streams, rivers and lagoons of fresh water, in coastal areas and the interior plains of Rio Grande do Sul.
native to the basins
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 Brazilian national list (Ministerial Ordinance GM/MMA No. 1.667/2026).
We found no species-specific rule beyond the region's general rules.
Allowed: Recreational fishing from shore, or from a boat without motor. Only handline or rod, line and hook, one gear per angler, up to 5 kg. Prohibited in floodplain lakes, within 1,500 m of dams, within 500 m of confluences, and in stretches listed in the rule (e.g., Turvo River).
Source: IN IBAMA nº 193/2008
Allowed: Recreational fishing from a boat or from shore, with a single hook, one gear per angler, up to 5 kg.
Source: IN IBAMA nº 197/2008
The teeth are strong: use pliers to remove the hook, hold it carefully and release it quickly.
Length-weight relationship W = a·Lb (a = 0.00912, b = 3.12; 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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Essential profile: size, length-weight, depth, countries and conservation come from FishBase and the cited regulations, and the texts were written from those sources. Season, time of day, sensitivities, technique and baits and lures are not included yet, because we did not find a good source for this species.
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.
