Bamin

This species is distinguished with the following characters: second dorsal fin soft rays 14 (rarely 13 or 15) pectoral fin rays 16-18 (mode 17, rarely 15 or 19), pectoral filaments 4; poredlateral line scales 71-80 (mode 73); scale rows above lateral line 9-12, below 13-15 (14); vomer with deciduous tooth plates on both sides, except in juveniles (< ca. 7.0 cm SL); posterior part of maxilla deep, 3-4% of SL; short tooth plate extension onto lateral surface of lower jaw, 7-9% SL. Colour of upper sides of head and trunk with slight darkish silver tinge, becoming lighter in lower sides; anterior margins of first and second dorsal fins blackish, remaining parts translucent and slightly blackish, respectively; pectoral fin membranes vivid yellow in life, except in large specimens > ca 35 cm SL which is dusky yellow; pectoral filaments white; anterior margin of pelvic fin yellow and other parts white; base of caudal fin yellowish, other parts blackish (Ref. 41639, 57343).

Procerovum Infestation 1. Parasitic infestations (protozoa, worms, etc.)

Neoechinorhynchus Disease. Parasitic infestations (protozoa, worms, etc.)

In Australia, fish are males at 24-47 cm FL, hermaphrodites at 25-46 cm FL and females at 28-72 cm FL. On the northeast Queensland coast, most blue threadfin are females by 45-50 cm FL. Hermaphroditic blue threadfin develop fom 1-2-year-old fish, and females first appear as 2-3-year-old individuals (Ref. 28736). Male fish probably commence sex reversal immediately after spawning (ie about April-May) and this condition may persist until after the next spawning period (Ref. 28736). The progression from hermaphrodites to females is complete by the following season.There is little information on the larvae, although nursery areas are known to be lower estuaries, tidal swamps and lagoons, and shallows along the foreshores (Williams 1997).

Amphidromous. Refers to fishes that regularly migrate between freshwater and the sea (in both directions), but not for the purpose of breeding, as in anadromous and catadromous species. Sub-division of diadromous. Migrations should be cyclical and predictable and cover more than 100 km.Characteristic elements in amphidromy are: reproduction in fresh water, passage to sea by newly hatched larvae, a period of feeding and growing at sea usually a few months long, return to fresh water of well-grown juveniles, a further period of feeding and growing in fresh water, followed by reproduction there (Ref. 82692).

Dorsal spines (total): 9; Dorsal soft rays (total): 13 - 15; Analspines: 3; Analsoft rays: 14 - 16; Vertebrae: 25

Occur inshore (Ref. 75154). There is little information on the life cycle movements of threadfin salmon. Tagging programs (Ref. 28741) have shown that adult blue threadfin move long distances along the coastline for at least 150 km. Blue salmon form large schools in feeding and spawning habitats in coastal shallows (Williams 1997). Feed on prawns and fish (largely members of Mugilidae, Engraulidae, and Sciaenidae) with occasional polychaetes. Frequency of crustaceans to fish in the diet varies seasonally. Larvae (7-30 mm TL) feed mainly on copepods and mysids but also take shrimps and prawn larvae (Ref. 57343). Juveniles (31-60 TL) feed on prawns shrimps and mysids (Ref. 57343).

Adults occur mainly over shallow muddy bottoms in coastal waters. Also enter rivers (Ref. 3479, 6390, 11230). Juveniles found in estuaries. During winter, adults ascend the rivers. They usually form loose schools, although larger fish are more often observed in pairs or singly (Ref. 6390). Feed on prawns and fish (largely members of Mugilidae, Engraulidae, and Sciaenidae) with occasional polychaetes. Frequency of crustaceans to fish in the diet varies seasonally. Larvae (7-30 mm TL) feed mainly on copepods and mysids but also take shrimps and prawn larvae (Ref. 57343). Juveniles (31-60 TL) feed on prawns shrimps and mysids (Ref. 57343). Protandrous hermaphrodites. Marketed fresh, frozen, and dried or salted.

fisheries: highly commercial; aquaculture: commercial; price category: high; price reliability: reliable: based on ex-vessel price for this species