redtail triggerfish
Xanthichthys mento · Balistidae · forage fish
Triggerfish that forms schools over reefs and near oceanic islands in the eastern Pacific, with a red tail in males. It is harmless to anglers.
Also called: peixe-porco-de-cauda-vermelha, puerco de cola roja, redtail triggerfish
- maximum
- 30 cm
- depth
- 6–130 m
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…
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hour by hour
slide your finger or mouse over the chart to see each hoursee hour-by-hour table
why this index at —?
choose 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.
the fishing month at a glance
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.
everything about the redtail triggerfish
who is the redtail triggerfish
Triggerfish of the family Balistidae, with a short, deep body, which forms schools over reefs at the edge of drop-offs, mainly near oceanic islands and coastal reefs. It occurs from Mexico to Colombia and Chile, at depths of 6 to 130 m, and reaches 30 cm. It feeds on zooplankton. Males hold territory for spawning and care, but not for feeding. Only females care for the eggs, and both parents guard the site. It is taken commercially, and also for aquariums.
Essential profile. Identification, where it occurs and rules, with data from FishBase and the cited regulations. Season, time of day, technique and bait are added once we have a good source for the redtail triggerfish; in the meantime, see the similar species.
identification
Short, deep body. Males are straw-yellow, with each scale outlined in black, forming a checkerboard, and the tail is red with a neon-blue band near the edge. Females have the checkerboard on a slate-gray to bluish background, with the tail also bluish. Balistes polylepis, from the same coast, reaches 76 cm, much more than the 30 cm of this species.
where found
Occurs in the eastern Pacific, from Mexico to Colombia and Chile, near reefs and oceanic islands. The species also lives in other parts of the Pacific, such as Hawaii and southern Japan.
Habitat: Reefs and drop-offs, in schools near the bottom and in the water column, from 6 to 130 m.
rules for the redtail triggerfish
Summary of the regulations we found, with the source for each. Rules change; before keeping or transporting fish, check with the state environmental agency.
We found no species-specific rule beyond the region's general rules.
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.
Harmless to anglers. Hold it by the body and release it quickly.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.02692, b = 2.91; FishBase (relação peso-comprimento bayesiana, estimativa)). It's an average: a fat or lean fish can vary by 10% to 20%.
estimated weight
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sources and references
Essential profile: size, length-weight, depth, countries and conservation come from FishBase and the cited regulations, and the texts were written from those sources. Season, time of day, sensitivities, technique and baits and lures are not included yet, because we did not find a good source for this species.
- scientific FishBase: Xanthichthys mento (ficha da espécie)Size, length-weight, depth, habitat, distribution, biology, and IUCN status. Page checked on Oct 13, 2026.
- scientific FishBase: nomes populares de Xanthichthys mentoNames by country and language.
similar species
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: