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Title: Fishing regulations, sexual dimorphism, and the life history of harvest
Freshwater recreational fisheries regulations are a vital tool for achieving social and ecological fisheries objectives. However, angler behavior and fish biology may interact to influence regulation efficacy in unexpected ways. We combined models of fish growth and angler behavior to explore how angler behavior interacts with fish life history to shape the probability of fish harvest given capture across ages, life-stages, and sexes of walleye (Sander vitreus). Compared to females, males grew more quickly as juveniles, matured earlier, and reached smaller maximum sizes. Male walleye were therefore vulnerable to harvest for more of their reproductive lives than females because males spent more time at sizes where anglers were very likely to harvest them. We suggest that restricting harvest of large individuals in sexually-dimorphic species may favor the survival of large, reproductive-aged females. Moreover, we show that combining models of fish growth and harvester behavior can provide insights into how harvest affects fish with complex life histories over the course of their lives.  more » « less
Award ID(s):
1735362
PAR ID:
10319746
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Canadian Journal of Fisheries and Aquatic Sciences
ISSN:
0706-652X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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