This overview of the roles of alien species in insect conservation
brings together information, evidence and examples from many parts of
the world to illustrate their impacts (often severe, but in many cases
poorly understood and unpredictable) as one of the primary drivers of
species declines, ecological changes and biotic homogenisation. Both
accidental and deliberate movements of species are involved, with alien
invasive plants and insects the major groups of concern for their
influences on native insects and their environments. Risk assessments,
stimulated largely through fears of non-target impacts of classical
biological control agents introduced for pest management, have provided
valuable lessons for wider conservation biology. They emphasise the
needs for effective biosecurity, risk avoidance and minimisation, and
evaluation and management of alien invasive species as both major
components of many insect species conservation programmes and harbingers
of change in invaded communities. The spread of highly adaptable
ecological generalist invasive species, which are commonly difficult to
detect or monitor, can be linked to declines and losses of numerous
localised ecologically specialised insects and disruptions to intricate
ecological interactions and functions, and create novel interactions
with far-reaching consequences for the receiving environments.
Understanding invasion processes and predicting impacts of alien species
on susceptible native insects is an important theme in practical insect
conservation.
