Abstract Diversification of harvest portfolios can benefit resource users by providing increased flexibility to respond to regulatory, economic, and environmental pressures. These adaptations, while important for maintaining harvesting opportunities, can lead to conservation challenges by shifting effort to other species or habitats. Using semi-structured interviews with charter fishing captains (N = 52) and logbook data, we examined shifts in the diversity of target species portfolios in a major recreational fishery in Alaska over three decades. To understand the role of regulation in affecting what species charter captains choose to target, we contrasted harvest portfolios in communities from two regions with differing histories of regulation. Portfolio structure was dynamic, with the majority of respondents reporting changes in the number of harvested species, relative preference for different species, or both since the 1990s. Diversification emerged primarily as a result of increased retention of historically less-preferred species, such as rockfishes, sablefish, and Pacific cod. Patterns of rockfish retention in charter logbook data mirrored patterns in targeting reported by respondents. Southeast Alaska captains largely attributed portfolio diversification and shifts in species preferences to greater restrictions on harvest of a primary target species (Pacific halibut), while Southcentral Alaska captains identified shifting customer interests and declines in some target species as driving changes. Our findings suggest that avoiding unintended conservation impacts of single-species regulations requires broader recognition of the multispecies nature of recreational fishing in management. Understanding fisher behaviors, values, and motivations is essential, so that managers may better anticipate the responses of fishers to new regulations.

中文翻译：

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阿拉斯加休闲渔业的收获组合多样化和紧急保护挑战

摘要 采伐组合的多样化可以通过提供更大的灵活性来应对监管、经济和环境压力，从而使资源使用者受益。这些适应虽然对于保持收获机会很重要，但可能会通过将努力转移到其他物种或栖息地而导致保护挑战。使用对包机捕鱼船长（N = 52）和日志数据的半结构化访谈，我们研究了阿拉斯加主要休闲渔业中目标物种组合多样性在过去三十年来的变化。为了了解监管在影响物种特许船长选择的目标方面的作用，我们对比了来自监管历史不同的两个地区的社区的收获组合。投资组合结构是动态的，大多数受访者报告了自 1990 年代以来收获的物种数量、对不同物种的相对偏好或两者都有变化。多样化的出现主要是由于对历史上不太受欢迎的物种（如石斑鱼、黑鲈和太平洋鳕鱼）的保留增加。包机日志数据中岩鱼保留的模式反映了受访者报告的目标模式。阿拉斯加东南部的船长们主要将投资组合多样化和物种偏好的变化归因于对主要目标物种（太平洋大比目鱼）捕捞的更大限制，而阿拉斯加中南部的船长将客户兴趣的变化和某些目标物种的减少视为推动变化的原因。我们的研究结果表明，要避免单一物种法规的意外保护影响，需要更广泛地认识到管理中休闲捕鱼的多物种性质。了解渔民的行为、价值观和动机至关重要，这样管理人员才能更好地预测渔民对新法规的反应。