Oogenesis and the spawning pattern in Greenland halibut from the North-west Atlantic

Gametogenesis in Greenland halibut Reinhardtius hippoglossoides from the North-west Atlantic is not synchronous between individuals of the same population suggesting that the spawning season is not well defined. Differences in oocyte size–frequency distributions in prespawning, spawning and spent conditions suggest that Greenland halibut are capable of de novo vitellogenesis prior to and during spawning, indicating that the spawning pattern is not determinate. Greenland halibut may be capable of fast-tracking oocytes to maturity, whereby during the spawning season oocyte batches may be brought quickly through vitellogenesis so as to increase the fish's yearly reproductive output. 1999 The Fisheries Society of the British Isles