2025-12-02 スウォンジー大学
Swansea Universityらが2025年に発表した研究では、アマゾン西部・中流ジュルア川流域において、現地漁師が持つ世代を通じた「伝統的知識（ローカルナレッジ）」と地域漁業の共同管理制度（コミュニティ・コ・マネジメント）が、世界最大級の淡水魚 ピラルク (Arapaima gigas) の持続可能な漁獲・保全において非常に有効であることを示しました。研究では、2011～2022年に13 の保護湖と19 の非保護湖で収集されたデータを元に、これら湖が地理的に連結するネットワークと魚の個体群動態モデルを構築。漁師が選んだ保護湖は、モデルに基づく最適戦略と比べて遜色なく、過剰漁獲の抑制と資源の保全に貢献していたことが明らかになりました。この成果は、伝統知識と定量的生態モデルを統合し、持続可能な自然資源管理の新しい枠組みを提示するものです。
＜関連情報＞
- https://www.swansea.ac.uk/press-office/news-events/news/2025/12/study-proves-how-local-knowledge-enhances-the-sustainability-of-interconnected-fisheries.php
- https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2664.70213
地域の知識は相互に関連した漁業の持続可能性を高める Local knowledge enhances the sustainability of interconnected fisheries
Carine Emer, Miguel Lurgi, Sérgio Timóteo, João Vitor Campos-Silva, Shai Pilosof
Journal of Applied Ecology Published: 01 December 2025
DOI:https://doi.org/10.1111/1365-2664.70213
Abstract
- Local knowledge (LK) refers to the ancestral understanding that Indigenous Peoples and local communities have developed over centuries through trial-and-error and hands-on management of natural resources. LK may provide valuable insights for biodiversity conservation and human well-being. However, its effectiveness remains under-explored at large scales, especially where multiple communities manage ecosystems. One example is fisheries, which form complex, interconnected networks where fish move across spatial boundaries between managed areas. Fisheries are critical for food security and income, yet face threats from overharvesting. Fisheries Co-Management (FCM)—a partnership between local communities and governments—leverages LK. However, the value of LK in designing protection strategies remains unclear.
- Using a process-based dynamical model parameterized with empirical data, we evaluated FCM strategies for pirarucu (Arapaima gigas) fisheries, which form a metapopulation network of protected and unprotected lakes in the Brazilian Amazon. We combined our metapopulation model with LK, fish biology and network theory to assess how lake protection, fishing quotas and illegal fishing impact pirarucu population abundance at the riverscape scale.
- By analysing 13 FCM-protected lakes and 18 unprotected lakes, we contrasted six hypothesis-driven management strategies against the current one, which is based on LK. In all strategies, protected lakes support higher pirarucu populations and buffer against increased fishing pressure, while unprotected lakes face population collapse due to the lack of fishing regulations. While a strategy that provides the best outcomes in terms of metapopulation persistence was based on pirarucu carrying capacity, the currently applied FCM strategy closely matched its efficacy.
- Synthesis and applications. Our modelling approach allows managers to compare alternative conservation strategies under different socio-ecological scenarios, highlighting trade-offs and guiding investment of effort and resources. While immediately valuable for pirarucu management in the Middle Juruá, the framework scales across tiers of applicability, each requiring progressively greater model adaptation: from supporting FCM in other Amazonian regions (with minimal adjustment), to adaptation for other riverine fisheries and ultimately to broader socio-ecological systems. In this way, we provide both system-specific insights and a flexible tool for advancing sustainable management of natural resources across contexts.
