Euthynnus affinis

Mackerel Tuna | Black Skipjack Tuna | Bonito | Dwarf Bonito | Eastern Little Tuna | False Albacore | Kawa Kawa | Lesser Bonito | Little Tuna | Little Tunny | Oceanic Bonito | Wavy-back Skipjack | Yaito Bonito
Euthynnus affinis
Euthynnus affinis, Maldives, Photo: Rick Stuart-Smith


Temperate Australasia, Tropical Indo-Pacific


Stout torpedo-shaped, silver body, dark blue upper back, and patch of wavy mackerel-like markings on upper rear body.


Max Size: 100 cm

Sea Temperature Range: 19.9-30.6°C

Depth: 0-200m

Habitat Generalization Index: N/A

Also referred to as the SGI (Species Generalisation Index), this describes the habitat niche breadth of the species. Species with values less than 15 are found in a relatively narrow range of reef habitat types (specialists), while those over 25 may be found on most hard substrates within their range (generalists). Learn more here.

Conservation and Rarity

IUCN Status: Least Concern

Occurrence: Rare (0.8% of sites)

Occurrence describes how often the species is found on surveys within its distribution. It is calculated as the % of reef sites surveyed by RLS divers across all the ecoregions in which the species has been observed

Abundance: Few (5 per transect)

Abundance is calculated as the average number of individuals recorded per RLS transect, where present.

Edit by: Joe Shields