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We examined differences in angling vulnerability among black crappies Pomoxis nigromaculatus, white crappies Pomoxis annularis, and their naturally produced hybrid offspring in Weiss Reservoir, Alabama, USA, during spring and fall of 1992 and 1993. Proportions of crappie phenotypes (determined by starch-gel electrophoresis) in the reservoir were estimated from trapnet and electrofishing collections. We collected angled crappies from local resort owners and crappie tournaments during spring and fall 1992 and 1993 to determine relative proportions of crappie phenotypes in angler catch. The proportion of black crappies caught by anglers was higher (P < 0.05) and the proportion of white crappies caught by anglers was lower (P < 0.05) compared to their proportions in trapnet and electrofishing catches from the reservoir. Although first-generation (F1) hybrids recruited to the minimum harvestable size (254 mm total length) earlier than either parental, these fish were not overly abundant in angler catches compared to their abundances in the reservoir. In fact, we found that in the fall of 1992 F1 hybrid crappies were less abundant in angler catches compared with their abundances in the reservoir. Black crappies were more vulnerable to angling than the other phenotypes, yet the proportion of this species did not decrease over time, likely because of moderate rates of crappie exploitation in Weiss Reservoir. Results of this study suggest that stocking of hybrid crappies for sport fishing purposes may not be as beneficial as once thought because they do not always contribute to the sport fishery relative to their abundance. |
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