FISHERY BULLETIN: VOL. 82, NO. 4 



from Kuwait in Kuronuma and Abe (1972:pl. 17), 

 a Japanese specimen in Masuda et al. (1975:79), 

 a Persian Gulf specimen in Randall et al. (1978: 

 212), a South African specimen in van der Elst 

 (1981:274), a Queensland specimen in Grant 

 (1982:pl. 325), and a 344 mm specimen from the 

 South China Sea in Kyushin et al. (1982:248). 



Biology. — Adults frequently undertake lengthy 

 seasonal longshore migrations (Lewis 1981). Mi- 

 grations occur along the entire eastern coast of 

 Queensland (McPherson 1981). Tongyai (1970:fig. 

 4) has mapped the migration route in the Gulf of 

 Thailand; from the Cambodian border in October 

 to the northernmost part of the Gulf of Thailand 

 in December to February, then south along the 

 west coast of the gulf in April. At least some 

 individuals are present year round in some areas, 

 e.g., Cambodia (Merceron 1970) and East Africa 

 (Williams 1964). Spawning apparently occurs 

 over a long period in some regions, e.g., October 

 to July in East Africa (Williams 1964), July to 

 December in Papua New Guinea (Lewis et al. 

 1974). Spawning times have been reported as 

 spring in Taiwan (Kishinouye 1923), October- 

 December on the Great Barrier Reef (Munro 

 1942), October to February, peaking in December 

 and January in Fiji (Lewis et al. 1983), May 

 to July in the coastal waters of Madras State 

 (Chacko et al. 1967), and December-February in 

 Madagascar (Fourmanoir and Crosnier 1964). 

 Munro (1942) described and illustrated the devel- 

 opment of artificially fertilized eggs and early 

 larvae from the Great Barrier Reef. Jones (1962) 

 described and illustrated five postlarvae and ju- 

 veniles (14.4-54.4 mm) from Vizhingam along the 

 coast of southern Kerala taken in shore seines 

 from February to June. The most complete larval 

 description is by Jenkins et al. (1984) of 62 larvae 

 (3.5-9.3 mm SL) from the shelf waters of the 

 Barrier Reef. Tongyai (1970) reported that juve- 

 niles 100-450 mm were taken in waters of high 

 turbidity and salinity in the Gulf of Thailand. 

 Juveniles were caught with dip nets in Papua 

 New Guinea waters in July, October, November, 

 and December (Lewis et al. 1974). Like other 

 species of the genus, S. commerson feeds primar- 

 ily on small fishes particularly anchovies such as 

 Anchoviella and Stolephorus and clupeids such 

 as Sardinella (South Africa — van der Elst 1981; 

 Madagascar — Prado 1970; Madras — Chacko et 

 al. 1967; Waltair, east coast of India— Rao 1964; 

 Vizhingam, southern India — Kumaran 1964; 

 Gulf of Manaar — Chacko 1949; and Cambodia — 



Merceron 1970). Other food items mentioned by 

 these authors include small carangids, Leiogna- 

 thus , squids such as Loligo, and penaeoid 

 shrimps. Feeding apparently takes place day and 

 night (Tongyai 1970). 



Interest to fisheries. — This species is taken 

 throughout its range by commercial, artisanal, 

 and recreational fisheries. Although it may be 

 present the year round, e.g., in the coastal water 

 of Madras State (Chacko et al. 1967), fisheries are 

 usually concentrated in some seasons, particu- 

 larly those with the best weather conditions for 

 fishing. Peak fishing seasons in some areas are 

 as follows: Taiwan — spring (Kishinouye 1923); 

 Great Barrier Reef — August to September (Grant 

 1978); Cambodia — the dry season, October to 

 April (Merceron 1970); Gulf of Thailand— Octo- 

 ber to May (Tongyai 1970); Waltair, northeastern 

 India — March-April, June-July, and December 

 (Venkata Subba Rao et al. 1981); Vizhingam, 

 southeastern India — September to April (Gopa- 

 lan Nayar 1958); and Malwan, south of Bombay 

 — February to March and October to December 

 (Kaikini 1961). There are important fisheries in 

 Fishing Areas 51, 57, and 71. The total catch 

 fluctuated between 63,290 and 79,047 t/yr in 

 1979-82 (FAO 1984). The five countries with the 

 largest reported catch in this period were Indo- 

 nesia, Philippines, Sri Lanka, Yemen, and Paki- 

 stan. The landings in Queensland were around 

 1,000 tons/yr during the mid-1970s but have 

 dropped to 730-770 tons in 1978-80 (McPherson 

 1981). The 1982 catch in Fiji probably exceeded 

 300 tons (Lewis et al. 1983). There is also an 

 important drift net fishery in India, but the catch 

 is not identified to species in the statistics. Drift 

 nets (gill nets) that are usually fished over night 

 appear to be the most important gear used for 

 S. commerson in Thailand, Malaysia, and India 

 (Tongyai 1970; Pathansali 1968; Kaikini 1961; 

 Chacko et al. 1967, respectively); other gear in- 

 cludes shore seines in Taiwan and India (Kishi- 

 nouye 1923; Gopalan Nayar 1958), trolling lines 

 in Taiwan, Malaysia, India, and East Africa 

 (Kishinouye 1923; Pathansali 1968; Dhawan et 

 al. 1972; Williams 1964, respectively). Hand lines 

 (bett-tok) baited with mackerel (Rastrelliger) 

 or squid (Loligo) and trotlines (bett-laak) with 

 spoons are also employed in the Gulf of Thailand 

 (Tongyai 1970). It is taken fairly commonly in the 

 inshore fishery along the Mediterranean coast of 

 Israel with trammel nets and occasionally with 

 purse seines (A. Ben-Tuvia 3 ). The yearly catch 



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