Global Conservation Program, Wildlife Conservation Society, Bronx, New York, United States of America.
PLoS One. 2014 Apr 16;9(4):e94667. doi: 10.1371/journal.pone.0094667. eCollection 2014.
This is the first assessment of catch rates for the legal, artisanal green turtle, Chelonia mydas, fishery in Caribbean Nicaragua. Data were collected by community members, monitoring up to 14 landing sites from 1991 to 2011. We examined take levels, and temporal and spatial variability in catch rates for the overall fishery, by region, and community using General Additive Mixed Models (GAMMs). More than 171,556 green turtles were killed during the period, with a mean estimated minimum 8,169±2,182 annually. There was a statistically significant decline in catch rates overall. Catch rates peaked in 1997 and 2002, followed by a downward trend, particularly from mid-2008 to the end of the study period. Similar downward trends were evident in both study regions. Community specific catch rate trends also indicated declines with decreases ranging from 21% to 90%. Decrease in catch rates in Nicaragua is cause for concern even though the principal source rookery at Tortuguero, Costa Rica, shows an increase in nesting activity. Explanations for the apparent discrepancy between the increasing trend at Tortuguero and decreasing catch rate trends in Nicaragua include: i) an increase in reproductive output, ii) insufficient time has passed to observe the impact of the fishery on the rookery due to a time lag, iii) changes in other segments of the population have not been detected since only nesting activity is monitored, iv) the expansive northern Nicaragua foraging ground may provide a refuge for a sufficient portion of the Tortuguero rookery, and/or v) a larger than expected contribution of non-Tortuguero rookeries occurring in Nicaragua turtle fishing areas. Our results highlight the need for close monitoring of rookeries and in-water aggregations in the Caribbean. Where consumptive use still occurs, nations sharing this resource should implement scientifically based limits on exploitation to ensure sustainability and mitigate impacts to regional population diversity.
这是对尼加拉瓜加勒比地区合法的、手工捕捉绿海龟（Chelonia mydas）渔业渔获率的首次评估。数据由社区成员收集，于 1991 年至 2011 年期间监测了多达 14 个上岸点。我们使用广义加性混合模型（GAMM），按区域和社区，分别检验了总体渔业、以及渔获率的渔获水平和时空可变性。在此期间，共捕杀了 171556 只绿海龟，估计每年平均有 8169±2182 只。渔获率总体呈下降趋势，具有统计学意义。渔获率在 1997 年和 2002 年达到峰值，随后呈下降趋势，特别是 2008 年年中至研究期末。两个研究区域均呈现出类似的下降趋势。社区特定的渔获率趋势也表明，下降幅度从 21%到 90%不等。尼加拉瓜渔获率下降令人担忧，尽管哥斯达黎加特鲁希略主要的繁殖地筑巢活动显示出增加的趋势。尼加拉瓜的渔获率下降趋势与特鲁希略繁殖地增加的筑巢活动之间存在明显差异，原因可能是：i）繁殖输出增加；ii）由于时间滞后，还没有足够的时间观察渔业对繁殖地的影响；iii）由于仅监测筑巢活动，因此尚未检测到其他群体的变化；iv）广阔的尼加拉瓜北部觅食区可能为特鲁希略繁殖地的大量海龟提供了避难所；和/或 v）在尼加拉瓜海龟捕捞区发生的非特鲁希略繁殖地海龟的贡献超出预期。我们的研究结果强调了需要对加勒比地区的繁殖地和水域聚集区进行密切监测。在仍然存在消费性利用的地方，共享这一资源的国家应实施基于科学的捕捞限制，以确保可持续性并减轻对区域种群多样性的影响。
