Abstract

Despite the global scale of gillnet bycatch, universal measures that effectively reduce bycatch of seabirds in gillnets have not been found. Bycatch in coastal gillnet fisheries is an ongoing threat for several seabird species. Strategies to reduce seabird bycatch in gillnet fisheries were evaluated, focusing on the effectiveness of time-area fishing restrictions and gear-switching to meet seabird conservation objectives, ensure fisher acceptance, and avoid unintended consequences. A review of case studies showed that variations in the spatial and temporal distributions of target and non-target species may cause a mismatch between time-area regulations and high bycatch, but consideration of bycatch species behavior can help define effective fine-scale spatial and temporal measures. The potential for meeting conservation objectives through gear-switching is promising, with some further development needed for successful application. Combining measures (e.g., time-area fishing restrictions, gear-switching, visual and acoustic deterrents) may be feasible in some regions, if fine-scale spatial and temporal information about the overlap of seabirds and gillnet gear is available. A holistic approach to reduce seabird bycatch in gillnets, including understanding of seabird biology, habitat preference, and feeding ecology combined with information about fishing activity, target species, and socioeconomic impacts provides a framework to develop mitigation measures.

摘要

尽管刺网兼捕的规模在全球范围内，但尚未找到有效减少刺网中海鸟兼捕的通用措施。沿海刺网渔业的副渔获物对几种海鸟物种构成持续威胁。评估了减少刺网渔业中海鸟兼捕的策略，重点关注时区捕鱼限制和渔具转换的有效性，以实现海鸟保护目标，确保渔民接受并避免意外后果。对案例研究的回顾表明，目标和非目标物种的空间和时间分布的变化可能导致时间区域规定与高兼捕之间的不匹配，但考虑兼捕物种行为有助于定义有效的精细尺度空间和时间措施。通过齿轮切换实现保护目标的潜力是有希望的，需要进一步开发才能成功应用。如果可以获得有关海鸟和刺网渔具重叠的精细尺度空间和时间信息，则在某些地区可以采取联合措施（例如，时区捕鱼限制、渔具转换、视觉和听觉威慑）。减少刺网中海鸟兼捕的整体方法，包括了解海鸟生物学、栖息地偏好和觅食生态学，结合有关捕鱼活动、目标物种和社会经济影响的信息，为制定缓解措施提供了一个框架。视觉和听觉威慑）在某些地区可能是可行的，如果可以获得关于海鸟和刺网渔具重叠的精细尺度空间和时间信息。减少刺网中海鸟兼捕的整体方法，包括了解海鸟生物学、栖息地偏好和觅食生态学，结合有关捕鱼活动、目标物种和社会经济影响的信息，为制定缓解措施提供了一个框架。视觉和听觉威慑）在某些地区可能是可行的，如果可以获得关于海鸟和刺网渔具重叠的精细尺度空间和时间信息。减少刺网中海鸟兼捕的整体方法，包括了解海鸟生物学、栖息地偏好和觅食生态学，结合有关捕鱼活动、目标物种和社会经济影响的信息，为制定缓解措施提供了一个框架。