Hypophthalmichthys nobilis · Xenocyprididae · omnivore
Bighead carp, with an enormous head, raised in fish farms and released into pay lakes. It filters plankton, exceeds 40 kg and rarely bites ordinary hook bait: the secret is the dough that breaks apart.
Also called: carpa-cabeçuda, carpa-cabeça-grande, cabeçuda
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.
Native to China, it was brought to Brazil for fish farming, in polyculture with other carps, and is now common in pay lakes; it also turns up in açudes (small dams) and reservoirs. It lives filtering plankton, mainly zooplankton, in mid-water and at the surface, with long, numerous gill rakers; that is why it rarely takes bait the traditional way. It grows very large: FishBase records up to 146 cm standard length and 40 kg. To spawn in the wild it needs long, warm rivers with strong current, and FishBase does not consider it established in Brazil: stocks come from captive breeding. Even so, it has been caught outside the tanks, such as in the Patos Lagoon estuary (RS). Releasing it into a river, reservoir or lake without a licence is an environmental offence.
Huge head, about a third of the body, eyes low, below the mouth line, and a large upturned mouth, with no barbels. Small scales. Dark grey body with large, irregular black blotches on the flank, pale to yellowish belly and a keel of scales between the pelvic fins and the anus. The silver carp is pale, unspotted, with a keel from the throat; the common carp has barbels and large scales.
Exotic, native to China. Raised in fish farms and released into pay lakes, açudes and reservoirs; listed as exotic in the rules of GO (Araguaia-Tocantins, Paranaíba and São Francisco), PR and MS, and already caught in Mirim Lagoon and the Patos Lagoon estuary (RS).
Habitat: Pay lakes, açudes, ponds and reservoirs; mid-water and surface.
introduced in
states
São Paulo, Paraná, Rio Grande do Sul, Minas Gerais, Goiás, Mato Grosso do Sul
Warm months, when plankton grows and it feeds more. In southern and southeastern winter it stays on the bottom and feeds little.
Daytime, with peaks at dawn and dusk. Feeds by day, most active early and late in the afternoon; on hot days it rises to the surface.
Water below about 18 °C cuts feeding.
Cold fronts knock the bite down; warm, stable days are best.
Little effect.
Cold rain slows activity; summer rain may activate it.
Not very relevant at pay lakes.
Wary of noise on the bank.
Wind pushes plankton and concentrates fish on the downwind bank.
Surface and mid-water, 0.5 to 2 m.
natural baits
accessories
Soft dough that releases a cloud in the water, with the chuveirinho hidden inside. It sucks in the cloud: set the hook when the float sinks slowly and let it run on the first run.
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: In its native range, the global IUCN assessment is Data Deficient (DD, September 2, 2010).
In Goiás, the bighead carp is on Annex II of the state rule in the Araguaia-Tocantins, Paranaíba and São Francisco basins: exotic species may be collected, killed and transported with no size or quantity limit. The same rule bans releasing exotic species into natural environments.
Source: IN Semad-GO nº 17/2026, art. 5º, art. 7º, § 5º, and Annex II
In the inland basins of the Paraná, the bighead carp is on the list of non-native fish with permitted catch and exempt from size rules, and the ordinance bans releasing captured non-native fish.
Source: Portaria IAT nº 650/2025, art. 3º, § 1º, and Annex II
In MS carp (all species) are on the list of exotic, allochthonous and hybrid species whose specimens may be added to the angler's bag limit, subject to the closed season.
Source: Decreto estadual MS nº 15.166/2019, art. 7º (as amended by Decreto nº 15.375/2020)
Introducing an exotic species, a hybrid or a fish outside its natural range without a technical opinion and licence is a federal environmental offence. This includes releasing fish from a tank, pay lake or aquarium into a river or reservoir.
Source: Lei federal nº 9.605/1998, art. 31, and Decreto federal nº 6.514/2008, art. 25
At a pay lake, follow the house rules. Outside it, don't take it to another water body; in Paraná, releasing non-native fish is banned.
White, tasty flesh with intramuscular bones; the large head is used in broths.
Length-weight relationship W = a·Lb (a = 0.00977, b = 3.1; FishBase). It's an average: a fat or lean fish can vary by 10% to 20%.
estimated weight
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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.
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.
