Caranx ignobilis
Giant trevally | Barrier Trevally | Big-headed Jack | Black Ulua | Giant Kingfish | Giant Ulua | Lowly Trevally | Yellowfin Jack | Yellowfin Trevally
Distribution
Tropical Indo-Pacific
Description
Robust body, steep head, and large mouth. Can rapidly turn on vertical silver bar markings or change to dark form. Row of large dark scutes from the tail base, with upturn in lateral line clearly visible in front. Easily confused with C. papuensis (Brassy Trevally) which has a white-margined lower tail lobe.
Information
Max Size: 170 cm
Sea Temperature Range: 16.8-31.3°C
Depth: 0-188m
Habitat Generalization Index: 5.88
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: Not Evaluated
Occurrence: Infrequent (6.4% 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 (4 per transect)
Abundance is calculated as the average number of individuals recorded per RLS transect, where present.
Edit by: RD Stuart-Smith, GJ Edgar, AJ Green, IV Shaw. 2015. Tropical Marine Fishes of Australia. Reed New Holland