| Popis: |
Trade-offs in energy allocation between growth and reproduction can result in variations in reproductive potential in fish with differing growth patterns. Spawning biomass is often used as a proxy for reproductive potential on the assumption that fecundity is directly proportional to body weight. We examined variations in the reproductive potential of Atka mackerel Pleurogrammus monopterygius by studying the effect of differential growth and condition patterns on fecundity, atresia, and egg energy. Fecundity and egg energy were determined for fish from two geographic areas, Seguam Pass and Amchitka Island, Alaska, and compared with those of fish held in captivity. These Atka mackerel showed distinct differences in growth and condition, with weight at length and length at age being the highest among captive fish, intermediate among fish from Seguam Pass, and lowest among fish from Amchitka Island. Realized fecundity showed that on average captive fish spawned seven batches, fish from Seguam Pass s... |
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