million fertilized eggs were collectedfrom this spawn.Spawning behavior is displayed incobia broodstock tanks quite frequently,but it becomes more active on the day ofactual spawning event. Hydration ofoocytes can be observed in maturedfemales as early as 11 AM (late spring)as evidenced by extended area along theposterior abdomen. Spawning, the timewhen the female(s) release oocytes intothe water column, occurs consistentlyshortly after sunset. In their prespawningritual, often several male cobiacan be seen literally trying to push theswollen female(s) out of the water. Fishare kept in spawning condition bymaintaining tank temperatures between25 and 28˚C. According to Arnold et al.(2002), 24-26°C is considered ideal forcobia in Texas and they may ceasespawning at temperatures between 28and 30°C. Similar maturation systemsare used in Texas for holding andspawning cobia broodstock (Kaiser andHolt 2005). Other personal observationsindicate that at lower latitudes such as S.Florida, Mexico, and Brazil, spawningsalso occur in the 28-30°C range. InPuerto Rico and Mexico, cobia stockedin both submerged and floating cages forgrow-out are often observed spawningnaturally.
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