A medium-sized snook of estuaries and rivers, with a concave head and protruding lower jaw, reaching about 56 cm. It strikes plugs and live bait near mangroves and channel mouths.
Also called: robalo-constantino, camurim (nome comum a vários robalos), robalo, tarpon snook, blackfin snook
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.
location
Sample location: choose yours to see the forecast for where you fish.
period
Reading the weather across 3 global models and 31 simulations…
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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
slide your finger or mouse over the chart to see each hour
see hour-by-hour table
why this index at —?
next 7 days
choose the day
chart: bar height = day's index · line = variation between models · striped = trend · fainter = less confidence
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 tarpon snook
overview
who is the tarpon snook
The robalo-constantino (tarpon snook, blackfin snook) is a medium-sized snook of the western Atlantic, from southern Florida, Mexico and the Antilles to Brazil. FishBase gives up to 56 cm and 1.5 kg, with the common size around 40 cm. It lives in coastal waters, estuaries and lagoons and enters rivers up to fresh water, where it prefers slightly salty water. It eats fish and crustaceans. It has a small-scale commercial fishery and FishBase records it as a sport fish. In Brazil, where it occurs from the North to the Southeast, it is one of the less well-known snooks, and like others of the genus it falls under the Espírito Santo and Bahia snook closed seasons.
fun facts
The English name, tarpon snook, is usually linked to the protruding lower jaw and head profile, which recall the tarpon.
It enters rivers up to fresh water, like the other snooks of the Atlantic.
The name blackfin snook, 'robalo de nadadeira preta', seems to refer to the dark fins.
how to recognize it
identification
Elongated, silvery body, compressed at the sides, with a concave head profile, large mouth and protruding lower jaw, reminiscent of the tarpon's and giving it its English name. The lateral line is dark and the fins are usually dark. Among river and estuary snooks it is medium-sized: larger than the robalo-espada (which rarely exceeds 36 cm) and much smaller than the robalo flecha. When in doubt, use counts from an identification guide.
Estuaries, mangroves, channels and lower rivers of the North, Northeast and part of the Southeast coast. Outside Brazil, it ranges from southern Florida and Mexico to the Antilles, the Caribbean coasts and northern South America.
Habitat: Estuaries, river mouths, mangroves, channels and soft-bottomed lagoons, in brackish or fresh water; enters rivers up to fresh water.
coast
North CoastNortheast CoastSoutheast Coastcoastal
calendar and clock
when to fish
best season
time of yearbest: Oct–Jan
JanFebSeaAprMayJunJulAugSepOctNovDec
The warm months, with rain and more brackish water, are best. In Espírito Santo and Bahia, snook fishing is banned from May to July; see the rules.
best time of day
Night and twilight. Most active at dusk, at night and at dawn, with the tide running.
weather, water and behavior
what affects the tarpon snook
sensitivity The little bars show how much each factor affects this species. Five full: it feels it a lot.
cold and cold fronts
Water below about 20 °C makes snook disappear from the banks; cold fronts knock fishing down.
atmospheric pressure
Stable pressure helps; a cold front brings rough sea and murky water and gets in the way.
moon
Moon phase and spring tides increase the current and activity at channel mouths.
rain
Light rain helps; heavy runoff leaves the water fresh and muddy and scatters the fish.
water level
Low river concentrates fish in the holes; high water spreads it through the mangroves.
noise
Very wary in clear water: approach by paddle or electric motor and keep your voice low.
wind
Strong wind ruins precise casts close to the mangrove.
tide
It is the main variable: a running tide, rising or falling, puts the fish in ambush at channel mouths and among the roots.
depth
Usually from 0.5 to 4 m, near roots, rocks and banks.
spinning reel 2500 to 3500 or low-profile baitcaster
line
braided line 10 to 20 lb
leader
fluorocarbon 20 to 30 lb, 60 to 100 cm (the gill cover edge of snook is sharp)
hook
hook no. 1/0 to 2/0 or small treble hook of the plug
lures
mid-water plug, 7 to 11 cm
8 to 10 cm shad on a 1/4 oz jig head
jerkbait
medium streamer on fly
natural baits
live shrimp
live sardine or anchovy
live small mullet
accessories
long-nose pliers
thin glove
polarized glasses
tip from an angler
Cast close to the mangrove roots and banks, with the current, and let the bait drift; the strike comes as it passes the edge of the shade.
what the law says
rules for the tarpon snook
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 (Portaria GM/MMA nº 1.667/2026). The snook closed season (Centropomus spp.) applies in Espírito Santo and Bahia.
Espírito Santo: snook closed season from May 1 to Jun 30
fishing prohibited from May 1 to June 3001/05 to 30/06ESSoutheast Coast
On the coast and in the inland waters of Espírito Santo, it is prohibited to fish for snook, white snook and camurim (Centropomus parallelus, C. undecimalis and Centropomus spp.) with any gear from May 1 to June 30. The robalo-constantino falls under 'Centropomus spp.'. Fishing competitions targeting snook are also prohibited from May 1 to August 31. Landing is tolerated until May 2.
fishing banned from May 15 to Jul 3115/05 to 31/07BANortheast Coast
On the coast and in the inland waters of Bahia, it is prohibited to fish for snook, white snook and camurim (Centropomus parallelus, C. undecimalis and Centropomus spp.) from May 15 to July 31. The robalo-constantino falls under 'Centropomus spp.'. Landing is tolerated until May 16, and transport, sale and processing of snook caught in the period are prohibited.
On the Caribbean coast of Nicaragua, the robalo-constantino (listed as bigbone snook) may not be caught below 30 cm total length; the same size applies to euryhaline fish of inland waters. The rule sets minimum catch sizes for fish and mollusks, without separating commercial from sport fishing in the section consulted.
Mexico (Gulf): the snook closed season from Jul 1 to Aug 15 does not mention this species
closed season from Jul 1 to Aug 15 for robalo blanco, robalo prieto and chucumiteconfirm with the agency
In federal waters of Tamaulipas, Veracruz, Tabasco and Campeche, the 2025 agreement bans fishing from July 1 to August 15 for robalo blanco (C. undecimalis), robalo prieto (C. poeyi) and chucumite (C. parallelus). The robalo-constantino is not mentioned. Since snooks look alike and share the same places, the safest course is not to fish for any snook in those waters and on those dates.
Mexico: up to 5 per species and 10 saltwater fish per day
5 specimens of the species per angler per day, within the limit of 10 saltwater fish
In recreational sport fishing in Mexican federal waters, each angler may keep up to 10 marine fish per day, no more than 5 of the same species. The robalo-constantino has no limit of its own in the rule. Fish above the limit must be returned alive to the water, and fish kept may not be sold. Anglers fishing from a boat need a Conapesca permit.
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.
The edge of the gill cover on snook is sharp: wet your hands, hold it by the lower lip or use pliers, without putting your finger in the gill. Take a quick photo and release it facing the current; the closed season prohibits keeping snook during the period.
in the kitchen
White, firm flesh, sold fresh; good baked, in moqueca or fried. It yields better fillets than the robalo-espada.
calculator
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.00851, b = 3.04; 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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sources and references
The seasonal 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, drawn from the literature below and from field experience of anglers and guides. They are not official data nor measurements 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. Common sizes and weights are ranges around the common length given by FishBase, with weight calculated from the length-weight relationship. The usual depth (0 to 10 m) is an editorial estimate: FishBase does not give a depth range.
scientificFishBase: nomes populares de Centropomus pectinatusNames by country and language. No popular Brazilian Portuguese name is recorded for the species: the app uses robalo-constantino (from the Spanish robalo constantino, Mexico and Nicaragua). Camurim is the general term for snooks in the Northeast.
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:
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