Lambaris in public reservoirs (nationwide)
01/11 to 28/02
Closed season for tambiú (yellowtail lambari) and redtail lambari in public reservoirs nationwide.
Source: IN IBAMA nº 51/2004
fishing forecast
lake tetra
Astyanax lacustris · Characidae · forage fish
Freshwater
The bamboo-pole fish. Many people's first fish, universal live bait and fried riverbank snack.
Also called: lambari, lambari-do-rabo-amarelo, tambiú, piaba
- common size
- 8–13 cm
- maximum
- 16 cm
- common weight
- 0.0–0.1 kg
- record/max.
- 0.1 kg
- depth
- 0.1–2 m
- ideal water
- 22–28 °C
fishing forecast
the right time
the right time
to be on the water
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…
0—
index Score from 0 to 100 for the fishing conditions of each hour. It reads weather, sun, moon, tide and the species' habits. It doesn't promise fish: it tells you when the water is on your side. 0–24 poor · 25–44 fair · 45–64 good · 65–84 very good · 85–100 excellent.
today
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confidence —
confidence How much you can trust the weather forecast for the day. It drops with distance and when the models disagree. It is not the chance of catching fish.
models and trend Up to 16 days, three global weather models (the European ECMWF, the American GFS and a high-resolution blend) read hour by hour; when they disagree, the light band on the chart widens. Beyond that it's a trend: 31 runs of the American GEFS model. Confirm when it's 1 week out.
window Consecutive hours with the index near the day's peak and no danger alert. It is the time to have the bait in the water.
hour by hour
tap or drag on the chart to read each hour · on a keyboard, arrow keyssee hour-by-hour table
why this index at —?
next 7 days
chart: bar height = day's index · line = variation between models · striped = trend · fainter = less confidencechoose the day
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.
4-week calendar
the fishing month at a glance
plan a trip
what's the best window for the crew?
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.
trend for the coming weeks
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 species
everything about the lake tetra
overview
who is the lake tetra
Small schooling characin, found in rivers, streams, lagoons and reservoirs of the Center-South. Eats just about anything: insects, seeds, algae and scraps. It is the first fish for many anglers, caught with a bamboo rod, quill float and dough. For sport anglers it is the live bait most used for trahira, peacock bass, golden dorado and black bass. It breeds several times a year and grows fast, so it holds up well to fishing pressure. Caught in quantity, it becomes the classic fried lambari. Follow local rules on catching and transporting live bait.
fun facts
- Raised in fish farms for sale as live bait and as a snack.
- Until 2016 the species was known as Astyanax altiparanae.
how to recognize it
identification
Small silver body with a greenish back. Long dark spot behind the head (umeral) and a dark spot at the base of the tail. Caudal fin yellow to orange. Other lambaris (red-tail, bocarra) have red tails or a bigger mouth. Piraputanga juveniles have red fins.
distribution
open on the large map where found
Upper Paraná, Pantanal and São Francisco: rivers, streams, lagoons, reservoirs and small farm ponds.
Habitat: Vegetated banks, slack water, small beaches, streams and reservoirs; schools near the surface.
native to the basins
ParanáParaguay (Pantanal)São Francisco
states
São Paulo, Minas Gerais, Goiás, Paraná, Mato Grosso do Sul, Mato Grosso, Bahia
when to fish
best season
time of yearbest: Oct–Mar
JanFebSeaAprMayJunJulAugSepOctNovDec
Spring and summer. In winter the schools go deeper and slower.
best time of day
Daytime. Active all day; most aggressive in the morning and late afternoon.
what affects the lake tetra
sensitivity The little bars show how much each factor affects this species. Five full: it feels it a lot.
sensitivity The little bars show how much each factor affects this species. Five full: it feels it a lot.
cold and cold fronts
Cold days scatter the school.
atmospheric pressure
Little effect.
moon
No significant effect.
rain
Light rain doesn't matter.
water level
Small effect; look for slack water.
noise
Tolerant; the chum holds the school.
wind
Wind makes it hard to see the float.
depth
Surface, 1 m.
how to fish
- rod
- bamboo or telescopic rod, 2.5 to 4 m
- spinning / baitcasting reel
- optional; line tied to the tip of the rod
- line
- monofilament 0.18 to 0.20 mm
- leader
- optional
- hook
- #14 to 18, midge type
lures
- micro jig 1/64 oz
- small dry fly
natural baits
- flour dough and cornmeal
- chopped worm
- bread
- insect larva
accessories
- quill or stick float
- chumbinho
- chum of fine cracked corn or bran
tip from an angler
Chum with fine cracked corn and cast the float into the middle of the school. Set the hook on the first dip, with a short wrist flick.
ready-made kit
first fishing trip (cheap beginner kit)
For anyone who's never fished and wants a simple kit for a pay lake, lake, reservoir or calm river, with natural bait.
guidefirst fishing trip: from zero to the water's edge
For anyone who has never fished: license, where to go, a cheap kit that works, how to rig a bobber line, how to bait the hook and what to do when the fish bites.
guidefishing with kids: safe, simple and fun
How to take a child fishing without scares: life jacket and supervision, hook and spine safety, gear that won't tangle, how to keep the fun going, and what the law says about licenses for minors.
rules for the lake tetra
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: Formerly called Astyanax altiparanae.
piracema closures in the basins where the species lives
Spawning closure (piracema) in the Paraná River basin
01/11 to 28/02SPPRMGGOMSDF
Allowed: Recreational fishing only for non-native species and hybrids (peacock bass, tilapia, black bass, carp, croaker, etc.; piauçu remains prohibited), with handline, simple pole, or rod with spinning or baitcasting reel, up to 10 kg + 1 fish. In rivers, from shore only; in reservoirs, from a boat or from shore. Prohibited: floodplain lakes, aquatic-animal bait, within 1,500 m of dams and waterfalls, and within 500 m of confluences. Tournaments only in reservoirs and only with non-native species.
Source: IN IBAMA nº 25/2009
Spawning closure (piracema) in Minas Gerais (state rule)
01/11 to 28/02MG
Allowed: Only exotic or hybrid species, 3 kg + 1 fish per day, with handline, rod, simple pole, or spinning or baitcasting reel. Nets prohibited. Keep the minimum distances from dams and reservoirs.
Source: Portarias IEF nº 154/2011 (São Francisco), 155/2011 (East) and 156/2011 (Grande/Paranaíba)
Closed season in Goiás (state rule)
01/11 to 28/02GO
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.
Spawning closure (piracema) in the Pantanal of Mato Grosso do Sul
05/11 to 28/02MS
Allowed: Subsistence fishing by riverside residents and authorized scientific fishing. Decree 15.166/2019 (art. 11, §5) allows catch and release only in February and only in the channels of the Paraguay and Paraná rivers. For the rest of the period, not even catch and release is allowed. Check the Imasul portaria for each season.
Source: Decreto estadual MS nº 15.166/2019, art. 11; IN IBAMA nº 201/2008
Spawning closure (piracema) in Mato Grosso (all basins)
01/10 to 31/01MT
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.
Spawning closure (piracema) in the São Francisco River basin (rivers and reservoirs)
01/11 to 28/02MGBAPEALSEGODF
Allowed: Recreational fishing from a boat or from shore with handline, rod, spinning or baitcasting reel, up to 5 kg + 1 fish. Prohibited within 1,000 m of dams, waterfalls and rapids, and within 500 m of confluences. Floodplain lakes have a longer closed season (see next item).
Source: Portaria IBAMA nº 50/2007
São Francisco: floodplain lakes
01/11 to 30/04MGBAPEALSEGODF
Allowed: No fishing in the floodplain lakes during the period.
Source: Portaria IBAMA nº 50/2007
catch and release
catch and release Releasing the fish alive, quickly and with a wet hand. During a closed season it isn't always allowed: what the regulation says applies.
catch and release Releasing the fish alive, quickly and with a wet hand. During a closed season it isn't always allowed: what the regulation says applies.
Fragile fish: wet your hand before picking it up and release it quickly.
in the kitchen
A whole fried lambari, crispy, is a classic riverbank snack.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.01862, b = 3.07; FishBase). It's an average: a fat or lean fish can vary by 10% to 20%.
estimated weight
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sources and references
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.
- scientific FishBase — Astyanax lacustris (ficha da espécie)Names, distribution, biology, length-weight relationship and references. Page checked on October 13, 2026.
- official Portaria GM/MMA nº 1.667, de 27 de abril de 2026 — Lista Nacional Oficial de Espécies da Fauna Ameaçadas de Extinção (peixes e invertebrados aquáticos)Most recent national list. The species is not on it (search by scientific name in the text published in the DOU, checked on October 13, 2026).
- official ICMBio/SALVE — Ficha de Astyanax lacustris (avaliação nacional do risco de extinção)National assessment by ICMBio, published in 2023. DOI verified on Crossref.
- scientific IUCN Red List — Astyanax lacustris (avaliação global: Pouco Preocupante, LC, 07/11/2018)Global assessment. Link given on the FishBase entry (Red List, version 2025-2).
- scientific Lucena, C. A. S.; Soares, H. G. (2016). Review of species of the Astyanax bimaculatus "caudal peduncle spot" subgroup sensu Garutti & Langeani (Characiformes, Characidae). Zootaxa 4072(1).Treats A. altiparanae as a synonym of Astyanax lacustris (checked in the abstract).
- scientific Súarez, Y. R.; Silva, E. A.; Viana, L. F. (2017). Reproductive biology of Astyanax lacustris (Characiformes: Characidae) in the southern Pantanal floodplain, upper Paraguay River basin, Brazil. Environmental Biology of Fishes 100: 775–783.
- scientific Ota, R. R.; Deprá, G. C.; Graça, W. J.; Pavanelli, C. S. (2018). Peixes da planície de inundação do alto rio Paraná e áreas adjacentes: revised, annotated and updated. Neotropical Ichthyology 16(2): e170094.Annotated list of species of the upper Paraná River, indicating native and non-native ones. Open access; species name checked in the text.
similar species
how we calculate
where each number comes from
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.
sources for this lookup
how accurate the forecast is
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: