World’s Worst Invaders article of ‘special significance’

Our invasions meta-analysis “Do invasive species perform better in their new ranges?” has been selected for F1000Prime and was recommended as an article of ‘special significance’ by Mark Lonsdale and Hazel Ruth Parry.

“This is a major study, using a rigorous meta-analysis to provide a very rare test of one of the assumptions of invasion biology – that invasive species perform better in their introduced range than the native range. The study is very valuable because it is surprising how rarely this assumption has been tested – indeed, the authors point out that they were not able to find comparative data for 60% of species labelled as the world’s worst invaders. They found that while half of the species tested were indeed performing better in their introduced ranges, for the other half, there was no obvious difference.

In truth, the idea that the impact of invasive species is felt through their size, greater fecundity, or greater abundance is just part of the picture: some species have an impact by simply introducing a novel life-form into a system in sufficient abundance (not necessarily greater than that in their native range) to make a difference to ecosystem function in the new range (e.g. Gamba grass in northern Australia, which has modified the fire regime to one of later, hotter fires {1}). It is also worth noting that the graphical presentation in the paper (as natural logarithms of the introduced range performance over the native range performance) visually underplays some of the substantial differences in performance shown by some of the species here.

The authors rightly call for more international research networks and partnerships to build data on invasive species from the native range. This is long overdue.”


1. Testing the grass-fire cycle: alien grass invasion in the tropical savannas of northern Australia. Rossiter N, Setterfield S, Douglas M, Hutley L. Divers Distrib 2003 May; 9(3):169-176; DOI: 10.1046/j.1472-4642.2003.00020.x