9368 - Laserfiche WebLink

Home Browse Search

overlapped in the 200-280 mm range. Some yearlings were the same size (340-380 mm) as their uplake counterparts. If forage remains limited and striped bass are restricted to a plankton diet, then even two-year-old fish overlap in size with yoy. Migration or differences in behavior results in discrepancies in growth among individual fish. Faster growing striped bass were frequently shorter lived than slow growing fish. Long-lived trophy fish greater than 15 pounds typically show a first growth ring from scale analysis that corresponds to small size (100-200 mm) at annulus formation. Conversely, fish noticeable larger than siblings from the same cohort often show first growth rings that indicate a size larger than 250 mm at first annulus formation. A 250-mm striped bass has a scale that measures 65-70 mm at a magnification of 24 times. These fast growing fish do not often persist longer than 5 or 6 years. Only a small number of individuals live longer than 6 years with the majority of the population succumbing to natural mortality or sport harvest before that time. striped bass over 20 pounds consistently show an initial growth ring that corresponds to relatively small size at first annulus formation and consistent growth each year thereafter. still the 575 mm fish has a scale radius of 200 mm (24 X magnification) regardless of how old it is. FOOD HABITS Lake Powell striped bass preferred threadfin shad over any other food item available. When shad were not readily available striped bass adults ate crayfish as a secondary food source (Table 4) while juvenile striped bass consumed zooplankton (Table 5). Other fish species were eaten only occasionally. In years when shad were limited in open water striped bass were forced to consume alternate prey. The schooling nature of striped bass makes them extremely proficient at feeding in open 14