Actinopteri (ray-finned fishes) > Trachichthyiformes
(Roughies) > Trachichthyidae
Etymology: Hoplostethus: Greek, hoplon = weapon + Greek, stetho, stethion = brest; literal = to prick a little breast (Ref. 45335).
Environment: milieu / climate zone / depth range / distribution range
Marine; bathypelagic; oceanodromous (Ref. 51243); depth range 180 - 1809 m (Ref. 6390), usually 400 - 900 m (Ref. 3583). Deep-water; 3°C - 9°C (Ref. 36694); 65°N - 56°S, 84°W - 168°W
Western Atlantic: Gulf of Maine (Ref. 4784) [in error according to Moore (Fishes of the Gulf of Maine, in press), should be off northern Nova Scotia]. Eastern Atlantic: Iceland to Morocco; Walvis Bay, Namibia to off Durban, South Africa. Indo-Pacific: south-central Indian Ocean and New Zealand. Eastern Pacific: Chile (Ref. 27363). Several stocks may exist as suggested by distinct spawning sites and seasons.
Length at first maturity / Size / Weight / Age
Maturity: Lm 37.0, range 18 - 32.5 cm
Max length : 75.0 cm TL male/unsexed; (Ref. 36696); common length : 40.0 cm TL male/unsexed; (Ref. 4181); max. published weight: 7.0 kg (Ref. 36697); max. reported age: 149 years (Ref. 3680)
Inhabits deep, cold waters over steep continental slopes, ocean ridges and sea-mounts. Shallow range of usual occurrence from Ref. 27121. Appears to be dispersed over both rough bottoms and steep, rough grounds where it feeds on crustaceans and fish. In New Zealand, the main prey include mesopelagic and benthopelagic prawns, fish, and squid, with other organisms such as mysids, amphipods and euphausiids occasionally being important (Ref. 9072). Juveniles feed mainly on crustaceans (Ref. 27075, 27076). Grows very slowly and is one of the longest lived fish species known. Based on parasite and trace-element analyses, orange roughy is a sedentary species with little movement between fish-management zones (Ref. 27089). Little is known of the larvae and juveniles which are probably confined to deep water (Ref. 27088). The fishery targets sporadically formed dense spawning and non-spawning aggregations. Marketed fresh and frozen; eaten steamed, fried, microwaved and baked (Ref. 9988). Because of severe overfishing the species has been listed as threatened by the Australian Government in 2006.
Orange roughy are synchronous annual spawners (Ref. 7030). They form dense spawning aggregations over sea hills and slopes. Eggs and sperms are shed into the water at the same time. Individual males appear to spawn over a 1-2 week period and females spawn for up to 1 week. Little is known of the larvae and juveniles.
Maul, G.E., 1986. Trachichthyidae. p. 749-752. In P.J.P. Whitehead, M.-L. Bauchot, J.-C. Hureau, J. Nielsen and E. Tortonese (eds.) Fishes of the north-eastern Atlantic and the Mediterranean. UNESCO, Paris. Vol. 2. (Ref. 4784)
IUCN Red List Status (Ref. 123251)
CITES (Ref. 123416)
Threat to humans
Fisheries: highly commercial
Estimates based on models
Preferred temperature (Ref. 115969
): 3.5 - 8.4, mean 6.6 °C (based on 754 cells).
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.02239 (0.01605 - 0.03122), b=3.08 (2.99 - 3.17), in cm total length, based on LWR estimates for this species (Ref. 93245
Trophic level (Ref. 69278
): 4.3 ±0.1 se; based on diet studies.
Resilience (Ref. 120179
): Very Low, minimum population doubling time more than 14 years (K=0.04-0.06; tm=5-33; tmax=140; Fec=10,000).
Prior r = 0.06, 95% CL = 0.04 - 0.10, Based on 3 stock assessments.
Vulnerability (Ref. 59153
): High to very high vulnerability (73 of 100) .