spottedhalibut,usinghistologicalandmorphometricmethodsandradioimmunoassay.Inaddition,weanalyzedtherelationshipbetweenthegonadosomaticindex(GSI),conditionfactor(CF),hepatosomaticindexHSI),sexsteroidlevelsandtemperatureorphotoperiod.Oocytedevelopmentwasasynchronousandthehalibutexhibitedbatchspawningbehavior.Wedividedoocytegrowthinsexuallymaturefemalesintofivephases.Similarly,theovarianmaturationcyclewasdividedintofourstages.,HSI,andCFallincreasedpriorto,orduringthepeakphaseofvitellogenicgrowthcorrespondingtogonaddevelopment.TheGSIwaspositivelycorrelatedwithHSIandCF.Temperaturehadagreaterinfluenceongonadmaturation(GSIandHSI)thanphotoperiod.ThelevelofserumestradiolbegantoincreaseinNovemberandpeakedinJanuary,thereafterdecreasingtoarelativelylowleveluntilthefollowingreproductivecycle.ThelevelofserumtestosteronepeakedinOctober,twomonthsearlierthanofthepeakinestradiol.Wefoundapositiverelationshipbetweenthelevelsofestradiolandtestosterone.Bothtemperatureandphotoperiodhadasignificantpositiveeffectonlevelsofserumestradiol,whichwasalsopositivelycorrelatedwithGSIandHSI.Inaddition,temperatureandphotoperiodhadasignificanteffectonHSIandCF,respectively.Ourresultsprovideinsightintothephysiologicalandendocrinemechanismscontrollingtheannualreproductivecycleofcaptivefemalespottedhalibutbrood.Inaddition,ourobservationsprovideguidanceforbroodstockprogramsandforthedeterminingtheoptimaltimingforhormoneinducedspawning.