Data from: Identifying links between the biodiversity impacts and monetary costs of alien birds

This dataset accompanies a published paper (Evans et al. 2023) which aims
to identify links between the biodiversity impacts and monetary costs of
alien bird species. In this paper we used mixed-effects models to test:
(1) whether alien bird species with severe biodiversity impacts also had
high monetary costs; (2) whether specific types of biodiversity impacts
were associated with high monetary costs; and (3) whether certain factors
caused alien bird species to have both severe biodiversity impacts and
high monetary costs. This dataset includes all data used for the analysis,
including biodiversity impact scores and monetary costs for each alien
bird species, and the variables tested for their influence on these
biodiversity impacts and costs. Please refer to Evans et al. (2023) for
details on the methods used. The abstract to the published paper follows.
Alien species can be damaging to native biodiversity, human well-being and
the economy. Identifying the complete range of impacts they cause, and the
ways that these impacts are connected, may inform the prioritisation of
management actions to mitigate impacts. Using datasets on the biodiversity
impacts and monetary costs (damage and management costs) of alien birds,
we aimed to establish whether species with the most severe biodiversity
impacts also had the highest costs; whether types of biodiversity impact
were associated with high costs; and whether specific factors associated
with alien species are linked to both damaging biodiversity impacts and
high costs. We identified a positive relationship between a specific type
of biodiversity impact (predation) and costs, possibly because predation
by alien birds can be severely damaging to native species and therefore
attracts management actions. However, predation impacts are likely to
occur more frequently and to be easier to identify than some other impact
mechanisms such as hybridisation and transmission of diseases, and they
are therefore likely to be more frequently managed, and hence to have
costs. We identified a specific species characteristic (generalism) to be
associated with severe biodiversity impacts and high costs, probably
because generalist species have greater opportunity to cause impacts,
whether they be on biodiversity or the economy, or both. We also found
widely distributed alien birds to be associated with high costs, probably
also because these species have greater opportunity to cause impacts.
Management interventions that prevent the introduction of both predatory
and generalist alien bird species, or that reduce their geographic
distribution at early stages of invasions, may have significant
biodiversity and economic benefits.