slender thread herring
Opisthonema bulleri
Pacific thread herring, with a spindle-shaped body, less abundant than the others of its genus in the region. It is taken in subsistence fishing.
Also called: sardinha-de-fio-esguia, arenque de hebra, machete del norte, pinchagua, slender thread herring
- maximum
- 20 cm
- depth
- 0–50 m
who is the slender thread herring
A sardine of the family Dorosomatidae, with a spindle-shaped, compressed body and the long filament at the end of the dorsal fin, a trait of the genus. It reaches 20 cm, and its common size is 18 cm, measured without the tail. It forms schools and lives from Baja California, Mexico, to Peru, in coastal and shelf waters down to 50 m. It is the least abundant of the genus's sardines in the eastern Pacific. It eats crustaceans and pteropods, small planktonic snails. It is taken in subsistence fishing, almost always together with other thread herrings.
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 slender thread herring; in the meantime, see the similar species.
fun facts
- It is the least abundant of the genus's sardines in the eastern Pacific.
identification
Spindle-shaped, compressed sardine with the long filament at the end of the dorsal fin, a trait of the genus. In the same region, the Pacific thread herring (Opisthonema libertate) and the middle thread herring (Opisthonema medirastre) are of the same genus and look alike; among the three, the safe separation is by gill rakers, which are fewer in this species. The middle thread herring also has a dark spot behind the gill slit and a yellow band on the flank.
Loading the next 7 days…
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.
Essential profile: the index uses a general fish model (weather, sun, moon and tide), without a season or time of day specific to this species.
where found
From Baja California, Mexico, to Peru, in coastal Pacific waters.
Habitat: Coastal and shelf waters, in schools, down to 50 m deep.
rules for the slender thread 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.
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.
Harmless. It almost never shows up on the line; it is a fish with delicate skin that goes into subsistence nets: handle it with a wet hand.
in the kitchen
It is caught in subsistence fishing, for local consumption.
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.00871, b = 3.06; FishBase (relação peso-comprimento bayesiana, estimativa)). It's an average: a fat or lean fish can vary by 10% to 20%.
estimated weight
—
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: Opisthonema bulleri (ficha da espécie)Size, length-weight, depth, habitat, distribution, biology, and IUCN status. Page checked on Oct 13, 2026.
- scientific FishBase: nomes populares de Opisthonema bulleriNames by country and language.
