The Impact of Condition on Reproduction in Flemish Cap Cod

نویسنده

  • George R. Lilly
چکیده

The impacts of fish condition on reproduction have not been examined previously for Flemish Cap cod. It is known that a substantial portion of female cod skipped spawning during the late-1970s and 1980s (Walsh et al., MS 1986) and it was speculated that this might be as a result of poor condition. The purpose of this paper was to determine if there is a relationship between condition and maturity in Flemish Cap cod, both male and female, and to determine if there was a relationship between condition and the probability of spawning in female cod. There was no significant effect of relative body condition (Kr) on the probability of being an adult for either male or female cod. For males there was also no significant effect of relative liver condition (LKr) on the probability of being an adult. For female cod there was a significant effect of LKr on the probability of being an adult, after accounting for the effects of age and length. However, LKr accounted for only a small portion of the deviance (1%) compared to the deviance accounted for by the combined effects of age and length (69%). There was no significant effect of Kr on the probability of spawning in adult females, however there was a significant impact of LKr with females with higher LKr having a greater probability of spawning.

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تاریخ انتشار 2004