Mylossoma albiscopum · Serrasalmidae · omnivore
A small, silver pacu from the Amazon várzea, one of the best-selling fish in Amazonas markets. It eats fruit and seeds and nibbles small hooks.
Also called: pacu-manteiga, pacu-comum, pacu, pacu-branco
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.
Disc-shaped pacu that lives in whitewater rivers and in the várzea lakes and channels of the Amazon. It eats fruit, seeds and insect larvae, and enters the flooded forest during the flood. Spawning is prolonged, with two peaks during the rise. It is one of the most important species in Brazilian Amazon commercial fishing. Until 2018, all Amazonian pacu-manteiga were called Mylossoma duriventre; the revision of the genus separated two very similar Amazonian species, M. albiscopum and M. aureum, which reach the markets together. On a small hook with fruit or dough, it fights well for its size.
Tall, disc-shaped, very compressed and silver body; the belly has a keel of spines (serrilha). Small head and short snout, with crushing teeth, without the cutting teeth of piranhas. Dark spot on the gill cover, missing or faint in M. aureum. Much smaller than the pacu and tambaqui.
Whitewater rivers and várzea lakes of the Amazon basin (Solimões-Amazonas, Madeira, Purus, Juruá). In the Tocantins-Araguaia the pacu-manteiga is another species, Mylossoma unimaculatum, and in the Pantanal the pacu-peva is M. duriventre.
Habitat: Várzea lakes, paranás, channels and flooded forest in the flood; river channel during migration.
native to the basins
states
Amazonas, Pará, Amapá, Acre, Rondônia, Roraima
In falling water and the dry season (August to November in central Amazonia) the fish concentrates in lakes and channels. In the flood it disappears into the flooded forest. There is a closed season from Nov 15 to Mar 15 in several states.
Daytime. Feeds during the day, most active in the early morning and late afternoon.
Cold snaps (friagem) shut down activity for a few days.
Stable pressure helps.
Little known effect.
Light rain doesn't bother it.
A falling lake concentrates the school.
Wary: approach quietly.
Little effect.
Shallow to mid-water, 0.5 to 3 m.
natural baits
accessories
Bait on the float, close to the vegetation on the bank. Strike quickly: it nibbles and lets go.
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 (Ordinance GM/MMA 1.667/2026). ICMBio assessed the related species M. aureum and M. duriventre; we found no national entry under the name M. albiscopum.
In AM, AC, PA and AP the pacu (Mylossoma spp.) is in Annex II of the ordinance, with fishing prohibited from Nov 15 to Mar 15. Under art. 2 of the ordinance, anglers fishing with a handline or pole, line and hook are exempt from this ban, unless a stricter state rule applies; during the period the angler's limit is 5 kg + 1 fish.
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: 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
Small, hardy fish: remove the hook in the water and release it.
Fatty, tasty meat. Grilled over coals, fried or in caldeirada; very common at Manaus markets.
Length-weight relationship W = a·Lb (a = 0.02455, b = 3.0; FishBase). It's an average: a fat or lean fish can vary by 10% to 20%.
estimated weight
—
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.
