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.
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hour by hour
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why this index at —?
choose the day
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 atlantic spanish mackerel
how to recognize it
Fusiform, silvery body covered in small scales, with about three rows of round to oval spots, orange in life. The first dorsal fin is black at the front and at the rear edge. The lateral line slopes gradually to the tail base. The king mackerel (cavala, S. cavalla) loses its spots as an adult and has a sharply dropping lateral line; the cero (S. regalis) has a dark band on its flank. FishBase warns that the sororoca (S. brasiliensis), the Pacific sierra (S. sierra) and the eastern Atlantic species (S. tritor) are often confused with this one: check the fish's origin.
Also called: sororoca-do-golfo, sierra, Atlantic Spanish mackerel, Spanish mackerel
don't confuse with:
where found
open on the large mapWhere to look: Open water of the coastal zone, between 10 and 35 m, in schools that migrate along the coast and follow sardines and anchovies. Larvae stay at the surface, in water of 19.6 to 29.8 °C.
It does not occur in Brazil. In Latin America, FishBase places the species on the Mexican coast of the Gulf of Mexico, up to Yucatán, and also lists Cuba, Jamaica and Puerto Rico; but the distribution text in the same entry stops at Yucatán and says the sierra is often confused with the sororoca and the Pacific sierra, so records from the islands call for caution. Outside the region, it ranges from Canada and Cape Cod to Florida, and does not occur in the Bahamas.
when to fish
best season
Migratory species: the school moves back and forth along the coast with water temperature and with the bait. We found no published fishing-season calendar for Mexico, Cuba or the other islands; the app's weights are estimates, and the best guide is warm, clear water with sardines at the surface.
best time of day
Daytime, with peaks at dawn and dusk. Hunts by day, most active at dawn and late afternoon, when bait schools rise near the surface.
what affects the atlantic spanish mackerel
cold and cold fronts
Below about 20 °C the school moves away from the coast; the range FishBase gives for the species is 20 to 30 °C.
atmospheric pressure
A cold front with rough seas scatters the bait and knocks out fishing for a day or two.
moon
Small effect; big tides concentrate bait at points and bay mouths.
rain
Little effect in open sea; murky water from a river or lagoon pushes the school away.
water level
Doesn't apply at sea. The equivalent is bait at the surface and clear water.
noise
An engine over the school makes it sink; approach from outside and cast at the edge.
wind
Light chop hides the line; strong wind makes it hard to see birds and feeding frenzies.
tide
At bay mouths and channels, the tidal current gathers bait and sierra.
depth
From the surface to about 35 m, following the bait.
how to fish
lures
- metal spoons, 10 to 30 g
- metal jigs, 20 to 40 g
- jigheads, 1/4 to 1/2 oz, with silicone or feather tail
- small mid-water plugs
natural baits
- live sardine or anchovy
- sardine or squid strips
- shrimp
tip from an angler
Reel in fast without pauses: sierra strike bait that is trying to escape. When birds are diving, stop the boat short of the school and cast to its edge.
- rod
- 6'6" to 7'6", fast action, 10 to 20 lb
- spinning / baitcasting reel
- spinning reel 3000 to 4000, with smooth drag and good line capacity
- line
- braided line 15 to 30 lb
- leader
- fluorocarbon 30 to 40 lb or fine steel wire 20 to 30 lb, 30 to 45 cm (the teeth cut thin line)
- hook
- single hook 1/0 to 3/0 on natural bait; small treble hooks on spoons and plugs
accessories
- long-nose pliers
- luvas
- insulated cooler with ice
catch and release
Use long-nose pliers, since the teeth cut, and hold the fish with a wet hand or a cloth. It tires quickly and suffers out of the water: unhook it with the fish in the water if you can, and release it promptly.
rules for the atlantic spanish mackerel
Rules change; before keeping or transporting fish, check with the state environmental agency.
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 details
In recreational sport fishing in Mexican federal waters, each angler may keep up to 10 marine fish per day, with at most 5 of the same species. Sierra is not among the species reserved for sport fishing (marlins, sailfish, swordfish, sábalo, roosterfish and dorado, up to 50 nautical miles from shore, item 0.3 of the rule) nor among those with their own limit (billfish, sharks, pescada, sábalo, dorado, roosterfish and baya), and it has no quota of its own. Fish over the limit are released alive, and sport-caught fish may not be sold.
Conservation: The species does not occur in Brazil and so is not on the national list (Portaria GM/MMA 1.667/2026). We found no specific conservation rule in the countries where it is fished.
how much it weighs without taking it out of the water
estimated weight
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how we calculate
Length-weight relationship W = a·Lb (a = 0.00776, b = 3.03; FishBase (relação peso-comprimento bayesiana, estimativa da própria espécie)). It's an average: a fat or lean fish can vary by 10% to 20%.
more about the atlantic spanish mackerel
The sierra, which we call sororoca-do-golfo here, is a Spanish mackerel of the northwestern Atlantic: it ranges from Canada and Cape Cod to Miami and along the Gulf of Mexico coast to Yucatán. It does not occur in Brazil, where the similar spotted mackerel is the sororoca (Scomberomorus brasiliensis). It lives in the coastal zone, between 10 and 35 m, in water of 20 to 30 °C, and migrates in large schools along the coast. It mainly eats sardines and anchovies, with some shrimp and squid. It matures at around 40 cm and the maximum recorded age is 5 years. Fishing methods include trolling, casting spoons and jigs, drifting live bait and, in some fisheries, using planes to locate the schools.
Family: Scombridae · predator
fun facts
- The genus name, Scomberomorus, combines Latin scomber (mackerel) with Greek moros (fool), according to FishBase.
- In some fisheries, planes are used to locate sierra schools, which migrate over long distances.
- The maximum recorded age is 5 years and maturity comes between 25 and 51 cm: the species grows and reproduces quickly.
in the kitchen
Sold fresh, frozen or smoked, and prepared fried, grilled or baked, according to FishBase. Ciguatera has been reported for the species: in reef areas, follow local health advice.
similar species
sources and references (5)
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: Scomberomorus maculatus (ficha da espécie)Size, length-weight relationship, depth, habitat, distribution, biology, cited fishing methods and IUCN status. Page checked on Oct 13, 2026. The country list (Cuba, Jamaica, Puerto Rico, Mexico) comes from FishBase itself; the distribution text stops at Yucatán.
- scientific FishBase: nomes populares de Scomberomorus maculatusNames by country and language.
- scientific IUCN Red List: Scomberomorus maculatus (avaliação global: Pouco Preocupante, LC, 10/11/2022)Global assessment. Link given on the FishBase profile (Red List, version 2025-2).
- scientific Collette, B. B.; Nauen, C. E. (1983). FAO species catalogue. Vol. 2. Scombrids of the world. FAO Fisheries Synopsis 125(2). Roma: FAO.Main FishBase reference for the species (description, distribution and confusion with other mackerels).
- official DOF: Modificação da NOM-017-PESC-1994, para regular a pesca deportivo-recreativa em águas de jurisdição federal do MéxicoText signed on Oct 14, 2013. Reserves species for sport fishing (item 0.3), daily limits at sea (4.9.1), catch and release of excess fish (4.9.5), and a ban on selling the catch (4.11). Text checked on Oct 13, 2026; the DOF publication date does not appear in the consulted text. The daily limit was confirmed only for Mexico; for Cuba, Jamaica and Puerto Rico we did not confirm species-specific rules.
how we calculatewhere 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: