Abstract Wildlife hunting for commercial products has been responsible for decline of many large vertebrates around the globe. An Amazonian example of this worldwide trend is the use of caiman and dolphins as bait for the piracatinga catfish fishery. While it is a controversial issue in Amazonia conservation, there is no data on key biological aspects, such as age and sex, of those animals illegally hunted for bait. This lack of data complicates understanding of the true impact of bait-hunting on the targeted species. In this study, we present results of one year of participatory monitoring of bait-hunting in 12 communities in the Mamiraua Sustainable Development Reserve (MSDR), Brazilian Amazonia, during which participants recorded aspects of hunting activity and biometric data of animals used as piracatinga bait. The piracatinga fishery at MSDR has distinct spatial and seasonal patterns, being concentrated close to distribution centers and intensifying during the dry season. Adult male black caiman is the main bait used by fishermen, but viscera of commercial fish provide a potential alternative bait source for the piracatinga fishery. All recorded bait hunting was for caiman, none for dolphins. Despite the predominant use of caiman as bait, MSDR caiman populations remain the largest within the species' distribution. We suggest that informal management of caiman conducted by MSDR residents has guaranteed regional sustainability of the piracatinga fishery. In a broader context, the current study highlights the potential for participatory research with local populations in formulating well-informed decisions for the conservation of natural resources and economic alternatives focused on the conservation of human-natural systems.

中文翻译：

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当捕食者成为猎物时：基于社区的对鲶鱼捕捞的凯门鳄和海豚的监测以及对亚马逊人类自然系统的更广泛影响

摘要 对商业产品的野生动物狩猎是全球许多大型脊椎动物数量减少的原因。这种全球趋势的一个亚马逊例子是使用凯门鳄和海豚作为 piracatinga catfish 渔业的诱饵。虽然这是亚马逊流域保护中的一个有争议的问题，但没有关于那些被非法猎杀诱饵的动物的关键生物学方面的数据，例如年龄和性别。缺乏数据使得对诱饵狩猎对目标物种的真正影响的理解变得复杂。在这项研究中，我们展示了在巴西亚马逊河马米拉瓦可持续发展保护区 (MSDR) 的 12 个社区进行为期一年的诱饵狩猎参与式监测结果，在此期间，参与者记录了狩猎活动的各个方面以及用作海盗诱饵的动物的生物特征数据. MSDR 的海盗渔业具有明显的空间和季节性模式，集中在配送中心附近，并在旱季加剧。成年雄性黑凯门鳄是渔民使用的主要诱饵，但商业鱼的内脏为海盗渔业提供了潜在的替代诱饵来源。所有记录的诱饵狩猎都是针对凯门鳄，没有针对海豚。尽管主要使用凯门鳄作为诱饵，但 MSDR 凯门鳄种群仍然是该物种分布中最大的种群。我们建议由 MSDR 居民对凯门鳄进行的非正式管理保证了海盗渔业的区域可持续性。在更广泛的背景下，