The UK government's proposed Infrastructure Bill for England and Wales gives new powers to control or eradicate invasive, non-native species (see go.nature.com/kbkvtt). However, what constitutes such a species needs careful definition to ensure that any use of these powers is beneficial for conservation.

The draft bill defines non-native species as those that are “not ordinarily resident in, or a regular visitor to, Great Britain”. This definition covers past native species that are now extinct, species that may become naturally established under a changing climate, and species listed in Schedule 9 of the Wildlife and Countryside Act. That list contains native species, including some that have been reintroduced into the wild, such as the barn owl (Tyto alba), capercaillie (Tetrao urogallus), chough (Pyrrhocorax pyrrhocorax) and red kite (Milvus milvus). The legislation could also preclude future species reintroductions, a tool to counter biodiversity loss.

The current definition has serious implications for wildlife management. Once a species is classified as non-native, it can also be classified as invasive — and would therefore be subject to invasive-species legislation.

Proposed amendments to address these problems have been rejected. If the bill is passed in its present form, it could lead to an irreversible loss of native biodiversity.