“Our work shows that the most appropriate management strategy for a pest species may depend on the ecological and environmental context of the pest in question.”

It has both theoretical and applied ramifications, and may alter the way invasive species management is carried out for species that invade multiple continents or a broad range of habitat types.

The work synthesizes independent studies of the same invasive thistle in different parts of its invaded range, and uses recently developed theory to understand differences between the populations.

Our work shows that the most appropriate management strategy for a pest species may depend on the ecological and environmental context of the pest in question. Biocontrol management strategies that were successful elsewhere may not work in different environments. This may explain commonly-observed inconsistencies in the success of the same management strategies for the same species in different parts of its invaded range. We also provide a way to address such differences.

I was lucky enough to collaborate at different times with two research groups, one directed by Dave Kelly at the University of Canterbury in Christchurch, New Zealand, and the other by Andy Sheppard and Tim Woodburn at CSIRO in Canberra, Australia, that were independently working on the demography of this species.

I would have expected the two studies to show very similar results, but they didn’t. Working out the reason why led to this paper.

Stronger links between pest management agencies in different countries would be very desirable. Also this shows the applied value of formally evaluating, with mechanistic ecological studies, the success of biological control programs.