The European trade ban on wild birds reduced invasion risks

Abstract

International wildlife trade is a major source of current biological invasions. However, the power of trade regulations to reduce invasion risks at large, continental scales has not been empirically assessed. The European wild bird trade ban was implemented in 2005 to counter the spread of the avian flu. We tested whether the ban reduced invasion risk in two European countries, where 398 nonnative bird species were introduced into the wild from 1912 to 2015. The number of newly introduced species per year increased exponentially until 2005 (in parallel with the volume of wild bird importations), and then sharply decreased in subsequent years. Interestingly, a rapid trade shift from wild-caught birds to captive-bred birds, which have lower invasive potential than wild-caught birds, allowed the maintenance of bird availability in markets. Our results demonstrate the effectiveness of a trade ban for preventing biological invasions without impacting the ability to meet societal demands.