Data from: Restricting access to invasion hubs enables sustained control of an invasive vertebrate

Biological invasions often occur through expansion of satellite
populations that become established at ‘invasion hubs’. Invasion hubs can
result from random dispersal events, but frequently arise when invading
individuals actively choose habitats using cues that signify high-quality
environments where the fitness consequences are positive. Theoretical
studies suggest that targeted control at invasion hubs can effectively
suppress the populations and impacts of invaders. In arid Australia, small
dams that provide water for livestock function as invasion hubs by
providing an invasive vertebrate, the cane toad Rhinella marina, with
refuge from extreme aridity during the annual dry season. Toads are
attracted to dams and use them as stepping stone habitats from which they
disperse during rainy periods. Here, we ask whether sustained control of
this invasive vertebrate can be achieved by converting invasion hubs into
ecological traps. We did this by manipulating invasion hub habitats to
induce a mismatch between toads' habitat preference and the fitness
consequences of their habitat choice to cause high mortality. We
constructed fences to exclude toads from dams and maintained these fences
for 1 year. This period encompassed periods of dry and wet seasonal
climatic conditions. Our manipulation did not alter the attractive cues
for invading toads which died en masse while attempting to settle at
fenced dams that prevented toads from reaching water. Toad populations at
the fenced dams were suppressed by 1–2 orders of magnitude compared to
unfenced controls and procedural controls. Toad populations remained
suppressed for a year after exclusion. By excluding toads from dams, we
converted invasion hubs into ecological traps and effectively thwarted the
reinvasion of cane toads. Our research suggests that water exclusion
devices could be used to prevent toad invasion or to control cane toad
populations in arid landscapes colonized by toads. Synthesis and
applications. Our study demonstrates that sustained control of invader
populations can be achieved by restricting their access to invasion hubs.
Control of invasive species via elimination of invasion hubs could be
conducted reactively, to control established populations of invaders, or
conducted strategically, by rendering invasion hubs unsuitable for
colonization ahead of the invasion front to prevent further population
spread.