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Over 1200 squids were captured by night lighting, trawling, or seining in the northern Gulf of Mexico for laboratory maintenance. Two types of recirculating sea water systems were designed and evaluated: a 2 m circular tank (1500 liter capacity) and a 10 rn long raceway (10,000 liters). Mean laboratory survival was: Loligo plei (12 to 252 mm mantle length, ML) 11 days, maximum 84 days; Loligo pealei (109 to 285 mm ML) 28 days, maximum 7 1 days; Loiiguncula brevis (27 to 99 mm ML) species-specific and were useful indices of the squids' condition. Key factors for lab oratory survival were (1) prevention ofskin damage, (2) tank systems with sufficiently large horizontal dimensions, (3) high quality water, (4) ample food supply, (5) no crowding, (6) maintaining squids ofsimilar size to reduce aggression and cannibalism, and (7) segregating sexes to reduce aggression associated with courtship, mating, and egg laying.

Over 2000 individuals of Lolliguncula brevis were collected from 1975 to 1979 in the northern Gulf of Mexico off the Texas coast; their growth and reproductive biology were analyzed by traditional fisheries methods (ELEFAN analysis of the length-frequency data). From 1994 to 1996, 112 squid were captured in Galveston Bay, near Galveston Island, Texas, and their age and growth determined by statolith increment analysis. The results were strikingly different between the two approaches. Length-frequency analysis of growth overestimated life span by a factor of three to seven times. Statolith increment counts, verified by laboratory growth validation experiments, indicate that this species is very short-lived, in the order of 100-200 days depending on temperature. A slight increase in temperature during the early stage of development can greatly shorten the life span. This study provides evidence that increased temperature during a squid's early growth period could markedly accelerate growth. Mature individuals occurred throughout the year, although there were many more mature males collected than females. Gonad growth and maturation in L. brevis appear to be associated more with size than with individual age. There is now compelling evidence that length-frequency analysis should be abandoned as a technique for determining squid growth.

Abstract. First culture results are presented from four major experiments (lasting up to 478 days) on the commercially important squid species, Lotigo forbesi Steenstrup, Details are provided on eggs, hatching, feeding, growth, survival, behaviour and sexual maturation. Best survival during the critical first 75 days was 15%. The hatchlings (up to 4 9 mm mantle length, ML) are the largest among the genus Loligo, and the largest squid grown was a male 155mm ML and I24g. First schooling was observed only 40-50 days post-hatching. Spawning was not achieved although males reached maturity, females had maturing ova and mating was observed. The largest giant axon measured was 425^l.m in diameter (from a female 130mm ML), a size suitable for most biomedical applications. Laboratory data suggest a 2-year life cycle compared to fishery data which suggest a 1-year cycle.

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