Domestic Cats (Felis catus) and European Nature Conservation Law—Applying the EU Birds and Habitats Directives to a Significant but Neglected Threat to Wildlife

Abstract

Free-ranging domestic cats (Felis catus) impact biodiversity through predation, disturbance, competition, disease and hybridisation. Scientific knowledge regarding these impacts has recently increased. This article interprets the European Union (EU) Birds and Habitats Directives (Nature Directives) in light of this knowledge. The outcome indicates that various obligations in the Directives, particularly concerning Natura 2000 sites and the generic protection of birds and other species, have significant implications for the management of free-ranging domestic cats. Regarding (unowned) stray and feral cats, these must be removed or controlled when they pose a threat to protected species and/or sites. Regarding (owned) pet and farm cats, the Nature Directives require EU Member States to ensure that letting cats roam free outdoors is forbidden and effectively prevented. Current practice across the EU does not yet conform to these requirements. Whereas the article identifies and assesses various factors that may explain this compliance gap, legally valid justifications appear absent.

Domestic cats and their impacts on biodiversity: A blind spot in the application of nature conservation law

“…The same applies with regard to all other Annex IV species vulnerable to domestic cats’ impacts, and also to ‘all species of naturally occurring birds in the wild state in the European territory of the Member States’ (Birds Directive, Article 1). The occurrence of native birds across the full extent of EU member states’ territories supports the far‐reaching conclusion that all EU member states are presently legally required to ensure that letting cats roam free outdoors is forbidden and effectively prevented (Trouwborst & Somsen, ). It should be noted, furthermore, that the possible exceptions in the Birds and Habitats Directives offer little scope for derogating from the required prohibitions (Trouwborst & Somsen, ).…”

“…To provide a cat example, feral cats pose a threat to the endangered Zino's petrel Pterodroma madeira at its remaining breeding sites on Madeira (BirdLife International, ). As these sites have Natura 2000 status, there is no doubt that EU law requires the Portuguese authorities to keep up the current cat trapping programme there or to otherwise prevent predation by cats (see further Trouwborst & Somsen, ).…”

“…As an interpretive analysis of the Directives in light of CJEU case law shows (Trouwborst & Somsen, ), the Court's broad interpretation of the term ‘deliberate’—as encompassing unwanted but accepted side effects—brings the act of allowing domestic cats to roam free within the scope of the various prohibitions. For instance, western green lizards Lacerta viridis/bilineata and agile frogs Rana dalmatina are listed in Annex IV of the Habitats Directive, and are distinctly prone to predation by domestic cats (Mori et al, ).…”

“…As will be recalled, the scope of various obligations—and therefore the degree of (non‐)compliance—partly hinges on what is ‘possible’, ‘feasible’ and/or ‘appropriate’. While the EU law obligations discussed above do not provide authorities with discretion in any of these regards, the reasons why they are nevertheless not fully complied with may also revolve around considerations of possibility and appropriateness (Trouwborst & Somsen, ). It seems helpful for present purposes, therefore, to identify and concisely assess such considerations.…”

“…Theoretically, conflict could also arise with other international obligations, although this appears unlikely. Even a dedicated pet welfare treaty like the 1987 European Convention on the Protection of Pet Animals indicates that ‘nothing in this Convention shall affect the implementation of other instruments for the protection of animals or for the conservation of threatened wild species’ (Article 2(3); see also Trouwborst & Somsen, ).…”