Phractocephalus hemioliopterus · Pimelodidae · predator
A strong, unmistakable catfish with a red tail and yellow band. Heavy fighter, sought after in rivers and pay lakes.
Also called: pirarara, bagre-de-cauda-vermelha
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 redtail catfish (pirarara) is one of Brazil's most beautiful and powerful catfish, with a broad head covered in bony plates, dark back, yellow band and red tail. It lives in rivers, lakes and channels of the Amazon and Araguaia-Tocantins, near logs, rocks and pools. It is omnivorous and opportunistic: it eats fish, crabs, fruit and whatever falls into the water. It fights with brute force and tries to dive into submerged timber and rocks. It is much sought in catch and release on rivers such as the Araguaia, and also in pay lakes in the Southeast, where it does well. Large ones exceed 40 kg and need heavy tackle.
Impossible to confuse: dark grey to black back, strongly contrasting lateral band and cream-yellow belly, red tail and part of the dorsal fin. Broad, flat head with bony plates. The jau is brown and mottled, without a red tail. The piraíba is uniformly grey. The dourada has a golden body and grey head.
Amazon and Araguaia-Tocantins basins. Very common in pay lakes in São Paulo, Minas Gerais and Goiás, from fish farming.
Habitat: Pools, channels, backwaters with logs and rocks, floodplain (várzea) lakes and flooded forest during high water.
native to the basins
states
Amazonas, Pará, Mato Grosso, Tocantins, Rondônia, Acre, Roraima, Amapá, Goiás, Maranhão
Dry season, June to October, in rivers. In a pay lake it produces all year, best in the warm months.
Night and twilight. Most active from late afternoon until dawn; in murky water it also feeds during the day.
In Southeast pay lakes, cold water slows activity.
Moderate effect.
Dark nights and new moon tend to be better.
Little effect; repiquete can trigger feeding.
Low water concentrates them in pools.
Not very sensitive.
Little effect.
Bottom of pools and channels; moves to the shallows at night.
lures
natural baits
accessories
The first seconds decide it: hold firm to pull the redtail catfish out of the logs or rocks before it finds a hole to hide in.
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).
Until Dec 31, 2028, redtail catfish caught in rivers of Mato Grosso may not be transported, stored or sold. Recreational anglers may only practice catch and release.
Source: Lei estadual nº 12.434/2024 (MT), arts. 19-B and 19-C of Lei 9.096/2009
In Tocantins the redtail catfish may only be kept between 80 and 120 cm.
Source: Portaria NATURATINS/GABIN nº 47/2026 (annexes amended by Portaria nº 105/2026)
Transport, storage and sale are fully prohibited for 5 years from Jan 1, 2024 for: cachara, caparari, dorado, jaú, matrinchã (Brycon spp.), pintado/surubim (Pseudoplatystoma spp.), piraíba, piraputanga, pirarara, arapaima (pirarucu), trairão and peacock bass (tucunaré, Cichla spp.). For recreational anglers: catch and release only. These 12 species may not even be eaten on site, since the 2 kg or 1 fish limit excludes the art. 19-B list. The law cites jaú as Zungaro zungaro; we also include the Pantanal jaú (Z. jahu) out of caution. The list may still change: § 2 (exotic and predatory species), § 3 (review through study) and the 3-year assessment planned for 2027. A TJMT news report of Jun 2, 2026 confirms the 12 prohibited species. The STF denied a preliminary injunction in the ADIs against the law in 2024; we found no merits ruling.
Source: Portaria Naturatins nº 47/2026, Annex I, as amended by Portaria nº 105/2026
Source: INIs MPA/MMA nº 12/2011 (Araguaia) and 13/2011 (Tocantins), minimum size annexes
Allowed: Sport and guided fishing only in reservoirs, catch and release with barbless hooks (no keeping, transporting or eating). Subsistence: up to 5 kg per day, for household consumption only.
Allowed: All fishing modalities are prohibited in rivers, including catch and release (Law 9.096/2009, art. 19-A). Exceptions: subsistence fishing from shore (3 kg or 1 fish, no transport or sale) and scientific fishing. Law 13.159/2025 now allows licensed sport fishing in UHE/PCH hydropower reservoirs, natural lakes and border rivers, subject to a scientific study and a license from the environmental agency. We have not confirmed whether these licenses are already being issued.
Allowed: Recreational fishing only in reservoirs, with handline, rod, or spinning or baitcasting reel. Fish may only be eaten on site, not transported. Competitions prohibited. Subsistence: 3 kg + 1 fish. State rules (GO and TO) may be stricter.
Allowed: Recreational fishing only in reservoirs, with on-site consumption. Subsistence: 5 kg + 1 fish. State rules may be stricter.
Allowed: In 2025/26: catch and release with barbless hooks and recreational fishing card; subsistence fishing on foot or from a rowboat, with simple pole or handline.
Source: Portaria Naturatins nº 244/2025 (2025/26 season); INIs MPA/MMA nº 12 and 13/2011
Allowed: The same recreational-angler exceptions as in Portaria 48/2007 apply (handline or rod, 5 kg + 1 fish), unless a stricter state rule applies.
Source: Portaria IBAMA nº 48/2007
Allowed: Recreational anglers with handline or rod, line and hook are outside the Annex II prohibitions, with a bag limit of 5 kg + 1 fish, unless a stricter state rule applies.
Source: Portaria IBAMA nº 48/2007
Allowed: Subsistence fishing only.
Source: Portaria IBAMA nº 48/2007
Allowed: See the exceptions in Portaria 48/2007 and the state rules for each bank.
Source: Portaria IBAMA nº 48/2007
Watch out for the spines on the pectoral and dorsal fins. Support the whole body, keep it in the water and avoid hanging a large fish by the mouth.
In the Amazon many people avoid the meat, considered "reimosa" (strong-tasting) and fatty. It is a fish to release.
Length-weight relationship W = a·Lb (a = 0.00912, b = 3.07; FishBase (bayesiano, espécie + forma do corpo da família)). 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.
