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
slide your finger or mouse over the chart to see each hoursee hour-by-hour table
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 graytail skate
how to recognize it
Skate with a flattened body, broad disc and thin tail set apart from the disc, like the other skates of the family. The tail is greyish, and the Spanish name (austral lija) refers to its rough skin. It lives at much greater depths than the shelf skates of the same region, between 94 and 585 m, so you have to fish deep to find it.
Also called: raia-lixa-austral, raya austral lija, graytail skate, austral ray
We don't have tips on season, bait or technique for this species yet.
where found
open on the large mapWhere to look: Sea floor, between 94 and 585 meters deep, from Uruguay to the Southern Ocean.
Southeast Pacific and Southwest Atlantic, from Uruguay to Patagonian Argentina, including the Falklands and the Southern Ocean. It does not occur in Brazil.
rules for the graytail skate
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.
IUCN global: EN · endangered.
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 = 0.00562, b = 3.13; FishBase (relação peso-comprimento bayesiana, estimativa pelo gênero e formato do corpo)). It's an average: a fat or lean fish can vary by 10% to 20%.
more about the graytail skate
The austral lija skate is a skate of the family Arhynchobatidae, with a flattened body and a disc formed by the pectoral fins. It reaches 49 cm. It lives near the bottom in deep water, between 94 and 585 m, from Uruguay to Patagonia, in the Falklands and in the Southern Ocean, from the Scotia Arc to the South Shetland Islands and the Antarctic Peninsula. It is oviparous, and the egg cases have horn-like projections on the shell. It turns up in commercial fishing and is endangered. It does not occur in Brazil.
Family: Arhynchobatidae · predator
sources and references (2)
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: Bathyraja griseocauda (ficha da espécie)Size, length-weight, depth, habitat, distribution, biology, and IUCN status. Page checked on Oct 13, 2026.
- scientific FishBase: nomes populares de Bathyraja griseocaudaNames by country and language.
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: