ridge scaled rattail
Macrourus carinatus · Macrouridae · predator
A slope grenadier of the South Atlantic, from Uruguay to Chile, caught at great depths. It is of no interest to sport fishing.
Also called: granadeiro-carenado, granadero, ridge scaled rattail, grenadier
- maximum
- 100 cm
- depth
- 500–800 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 ridge scaled rattail
who is the ridge scaled rattail
A fish of the family Macrouridae, with an elongated, tapering body, that lives near the bottom of the continental slope, between 500 and 800 m deep. It reaches 100 cm. It occurs in subantarctic and temperate waters on both sides of South America, from Uruguay to Argentina and Chile, and also in the Falkland Islands, South Africa and New Zealand. Uruguay also calls it granadero. It has commercial use: Argentina exports it to the United States under the name granadero. It is not a target of rod fishing.
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 ridge scaled rattail; in the meantime, see the similar species.
identification
Elongated body, brown to straw-colored, with the fins and the inside of the mouth darker, sometimes almost black. It has large eyes and a short, blunt snout. The underside of the head has scales, to a varying degree. In the same region, Macrourus whitsoni tends to be darker, dark brown, and lives deeper, between 600 and 1,500 m.
where found
In Latin America it occurs in Uruguay, Argentina and Chile, in waters of the South Atlantic and South Pacific.
Habitat: Continental slope, 500 to 800 m deep.
rules for the ridge scaled rattail
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.
The dorsal fin spines are not dangerous. Ascending from very deep water causes barotrauma, so release it carefully.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.00282, b = 3.18; 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: Macrourus carinatus (ficha da espécie)Size, length-weight, depth, habitat, distribution, biology, and IUCN status. Page checked on Oct 13, 2026.
- scientific FishBase: nomes populares de Macrourus carinatusNames 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: