scaled herring
Harengula jaguana · Dorosomatidae · forage fish
Menhaden of coastal and estuarine schools, from the eastern United States to southern Brazil. It is fished on a small scale and goes to market fresh or canned.
Also called: savelha-cascuda, sardina jaguana, sardineta jaguana, cascarua, scaled herring
- maximum
- 21 cm
- depth
- 1–5 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 scaled herring
who is the scaled herring
Sardine of the family Dorosomatidae, which forms schools in coastal waters over mud and sand bottoms, often near estuaries and brackish or hypersaline lagoons. It reaches 21 cm, and the common size is around 12 cm. It usually lives at 1 to 5 m depth and can go down to 22 m. It goes to market fresh or canned. It is often confused with Harengula clupeola, with which it shares nearly its whole range.
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 scaled herring; in the meantime, see the similar species.
fun facts
- Juveniles enter Guanabara Bay in May and leave in December or March, when they measure 7.5 to 8 cm.
identification
Slender silvery body with a deep belly: the lower profile is much more curved than the upper. It has no orange or red spot on the edge of the gill cover, and the dorsal-fin tip is not dark. To tell it apart from Harengula clupeola, which lives alongside it and looks similar, look at the belly and the spot: clupeola has a yellow or orange spot on the gill cover and a slimmer belly.
where found
In Latin America, it ranges from Brazil to Argentina and Uruguay, and also to the Caribbean, Colombia, Mexico and Venezuela, in coastal waters and estuaries.
Habitat: Shallow coastal waters and estuaries, from 1 to 5 m, over mud and sand bottoms.
coast
rules for the scaled herring
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.
No danger to the angler. As it is small, it usually ends up as bait or at market. If returned, release it promptly.
in the kitchen
It goes to market fresh or canned, on a small scale.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.00871, b = 3.07; 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: Harengula jaguana (ficha da espécie)Size, length-weight, depth, habitat, distribution, biology, and IUCN status. Page checked on Oct 13, 2026.
- scientific FishBase: nomes populares de Harengula jaguanaNames 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: