Abstract To effectively tackle the challenge of biological invasions through targeted strategies and mitigation measures, managers and policy makers require adequate reporting and flow of information. For this reason, the European ‘Natura 2000’ network of protected areas, which is the main conservation tool of the European Union, is supported by a standardized database. All threats to biodiversity are supposed to be reported in sufficient detail through that database. We compared the reported threats by ‘invasive non-native species’ in the Natura 2000 database with the actual cumulative impacts of invasive alien species on marine habitats in the Mediterranean using the CIMPAL index (Cumulative IMPacts of invasive ALien species). CIMPAL estimates cumulative impact scores on the basis of the distributions of invasive species and ecosystems, and both the documented magnitude of negative ecological impacts and the strength of such evidence. We showed that the threat of invasive alien species is substantially under-reported in the official documentation. Specifically, among the 1455 marine sites of the network, no threat was officially reported in one third of the sites. The threat of biological invasions was only reported in 154 sites, despite negative impacts by invasive alien species being predicted for 98% of all sites when using CIMPAL. In fact, in the subgroup of sites where no threats have been officially reported, the impacts predicted by CIMPAL were the highest. Such, inadequate and insufficient reporting of threats in the Mediterranean marine Natura 2000 sites presents a significant obstacle to the flow of accurate information needed to support conservation policies and marine management.

中文翻译：

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生物入侵的威胁在欧洲自然 2000 网络的海洋保护区中代表性不足

摘要 为了通过有针对性的策略和缓解措施有效应对生物入侵的挑战，管理者和决策者需要充分的报告和信息流动。因此，作为欧盟主要保护工具的欧洲“自然 2000”保护区网络得到了标准化数据库的支持。应该通过该数据库足够详细地报告对生物多样性的所有威胁。我们使用 CIMPAL 指数（外来入侵物种的累积影响）将 Natura 2000 数据库中“外来入侵物种”报告的威胁与外来入侵物种对地中海海洋栖息地的实际累积影响进行了比较。CIMPAL 根据入侵物种和生态系统的分布估计累积影响分数，以及记录在案的负面生态影响的程度和此类证据的强度。我们表明，官方文件中严重低估了外来入侵物种的威胁。具体而言，在该网络的 1455 个海洋站点中，三分之一的站点没有正式报告威胁。尽管在使用 CIMPAL 时预测 98% 的所有站点都会受到外来入侵物种的负面影响，但仅在 154 个站点报告了生物入侵的威胁。事实上，在没有正式报告威胁的站点子组中，CIMPAL 预测的影响是最高的。这样的，