Abstract
Invasive pests threaten food security and devastate ecosystems. A
universal problem in the management of such species is that small
populations can easily evade detection. This makes identifying new
incursions challenging and also complicates efforts to eradicate or
contain established populations. If invasive populations exhibited
strong Allee effects, such that small populations tend towards
extinction, then many of the issues associated with detecting small
populations could be avoided; these populations would go extinct without
intervention. Of course, invasive species rarely exhibit a strong Allee
effect, but new genetic technologies mean that it is conceivable to
impose one. Here we consider whether genetic Allee effects could be used
to control invasive species. We examine the simple situation of founder
establishment to test this idea. We use numerical and individual-based
modelling to examine the fate of founder populations sampled from a
larger core population containing a genetic load. Analysis of the effect
of various load and population parameters reveal that a genetic load can
dramatically reduce the establishment probability of small populations,
across a wide range of parameter space. A sterile effect is
substantially more effective than a lethal effect, but X-linkage has
minimal benefit over an autosomal load. Founder population extinction is
readily seen with less than one hundred loci when other load and
population parameters are constrained within realistic ranges. Our
findings suggest that driving a genetic load into a population may be a
means of making that population less invasive and easier to contain and
eradicate.