title: Sexual maturity cycle and spawning of Greenland halibut Reinhardtius hippoglossoides in the Davis Strait.
abstract: Female sexual maturation cycle and the main spawning time of Greenland halibut Reinhardtius hippoglossoides in the Davis Strait were studied through regularly collected samples during 1 year starting in spring 2003. Samples were collected from the southern slope of the Davis Strait Ridge between Canada and Greenland in the depth range 1000-1500 m. Female sexual maturation was described using different approaches: gonado-somatic index, visual macroscopic maturity stage index, histological microscopic maturity index and oocyte diameter measurements. A significant increase in the gonado-somatic index was seen from September onwards until February with a maximum estimated value of 18%. The proportion of mature fish increased from December until March. At the same time, the proportion of females with a low gonado-somatic index also increased from February, indicating that spawning had occurred and females were recovering. Oocyte diameter distribution revealed a leading cohort development during autumn through to December to February. A coupling between sexual maturity and fish condition was seen for females in maturing condition indicating a steady build up of stored energy in the liver from June to November.
authors.affiliation: Møreforsking AS Marin, PO Box 5075, Larsgården, N-6021 Alesund, Norway. agnes@mfaa.no
authors.forename: A C
authors.initials: AC
authors.lastname: Gundersen
authors.forename: C
authors.initials: C
authors.lastname: Stenberg
authors.forename: I
authors.initials: I
authors.lastname: Fossen
authors.forename: B
authors.initials: B
authors.lastname: Lyberth
authors.forename: J
authors.initials: J
authors.lastname: Boje
authors.forename: O A
authors.initials: OA
authors.lastname: Jørgensen
mesh_terms: D000818:Animals; D002170:Canada; D005260:Female; D005432:Flounder / Q000502:physiology*; D006116:Greenland; D009865:Oocytes / Q000502:physiology; D010053:Ovary / Q000502:physiology; D012098:Reproduction; D012741:Sexual Maturation