spotfin butterflyfish
Chaetodon ocellatus · Chaetodontidae · omnivore
Butterflyfish of shallow, clear-water reefs, with yellow or transparent fins, ranging from Florida to Brazil. It is an aquarium fish and rarely shows up on the line.
Also called: borboleta-amarela, isabelita amarilla, mariposa perla amarilla, spotfin butterflyfish
- maximum
- 20 cm
- depth
- 0–30 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
tap or drag on the chart to read each hour · on a keyboard, arrow keyssee 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 spotfin butterflyfish
who is the spotfin butterflyfish
Butterflyfish of the family Chaetodontidae, living on shallow, clear-water coral reefs, between 0 and 30 m, where it is usually common. It reaches 20 cm and matures near 14 cm. It occurs from Florida to Brazil. Larvae can be carried by currents northward, and juveniles have been seen as far as Massachusetts, USA, in summer. It pairs up for breeding and lays eggs in the water. At night, the body develops dark bands. In fishing it is almost always bycatch, and the species is valued in the aquarium trade.
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 spotfin butterflyfish; in the meantime, see the similar species.
fun facts
- At night, it develops dark bands on the body, according to the species description.
identification
White body with a black bar running through the head across the eye. In juveniles, a second black bar runs from the base of the soft dorsal fin to the base of the anal fin. The dorsal, tail and anal fins are yellow or transparent, and a narrow yellow band runs from the gill opening to the base of the pectoral fin. To tell it apart from Chaetodon sedentarius, which has a wide dark bar on the tail peduncle, look at the fin color and the yellow band.
where found
In Latin America it occurs on shallow reefs of Mexico, Cuba, Venezuela and Brazil, plus other Caribbean countries and the Guianas.
Habitat: Shallow, clear-water coral reefs, 0 to 30 m.
coast
rules for the spotfin butterflyfish
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 (Ministerial Ordinance GM/MMA No. 1.667/2026).
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.
It poses no danger to the angler. Being small, it should be handled with a wet hand and released quickly, without leaving it out of the water.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.0257, b = 3.02; 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
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: Chaetodon ocellatus (ficha da espécie)Size, length-weight, depth, habitat, distribution, biology, and IUCN status. Page checked on Oct 13, 2026.
- scientific FishBase: nomes populares de Chaetodon ocellatusNames by country and language.
- 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)The species is not on the list. Checked in the DOU of April 28, 2026.
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: