The European Natura 2000 (N2000) is the largest network of protected areas in the world. It was established to protect Europe’s most valuable and threatened species and habitats. While introduction pathways of invasive alien species (IAS) are strongly linked to human activities, they are not prohibited within N2000 sites, which makes them highly vulnerable to biological invasions. Nevertheless, very few studies have assessed the efficacy of the N2000 network to prevent the establishment and spread of IAS in protected sites. Evidence from the scarce available literature indicates that IAS are a serious threat to N2000 sites, especially those with high human accessibility. In this paper we examine the main legislative frameworks underlying the regulation of IAS in the European Union (EU) and explore their links to the EU Nature Directives that regulate the N2000 network. We then assess the extent to which these biosecurity legislative frameworks have successfully prevented IAS from entering, establishing and spreading in N2000 sites, by performing a top-down analysis at the EU, state and local levels; the latter is showcased by a case study in Spain, the country with the largest area under N2000. We conclude by discussing the regulatory aspects that need to be improved to address the IAS challenge to the N2000 network.

欧洲Natura 2000（N2000）是世界上最大的保护区网络。它的建立是为了保护欧洲最有价值和最受威胁的物种和栖息地。虽然外来入侵物种（IAS）的引入途径与人类活动密切相关，但在N2000站点内并没有禁止它们的引入，这使其非常容易受到生物入侵。但是，很少有研究评估N2000网络防止IAS在受保护站点中建立和传播的功效。现有文献不足的证据表明，IAS对N2000站点构成了严重威胁，尤其是那些人类可访问性较高的站点。在本文中，我们研究了在欧盟（IA）中对IAS进行监管的主要立法框架，并探讨了它们与监管N2000网络的欧盟自然指令之间的联系。然后，我们通过在欧盟，州和地方各级进行自上而下的分析，评估这些生物安全立法框架在多大程度上成功阻止了IAS在N2000站点中进入，建立和传播；后者是通过西班牙的案例研究来展示的，该国是N2000下面积最大的国家。最后，我们讨论了需要改进的法规方面，以应对IAS对N2000网络的挑战。通过在欧盟，州和地方各级进行自上而下的分析；后者是通过西班牙的案例研究来展示的，该国是N2000下面积最大的国家。最后，我们讨论了需要改进的法规方面，以应对IAS对N2000网络的挑战。通过在欧盟，州和地方各级进行自上而下的分析；后者是通过西班牙的案例研究来展示的，该国是N2000下面积最大的国家。最后，我们讨论了需要改进的法规方面，以应对IAS对N2000网络的挑战。