Research into the foraging behaviour of insects seeking patchy resourses, particularly in response to different densities and arrangements of host plants. Approaches include field experiments with cabbages and cabbage white butterflies, Pieris rapae; ragwort and its herbivores, as well as computer simulations of movement paths.

Collaborators: Phil Lester, Marcus Frean, William Kunin

Students: Marc Hasenbank, Jim Barritt, Cornelia Blaga, Yvonne Fabian

The Argentine ant was first recorded in New Zealand in 1990 near Auckland. Since that time it has rapidly spread through the northern half of the North Island. How much further will it spread and what are the factors that might limit its distribution? What effects will it have on indigenous ant species and other invertebrate biodiversity?

Fig 1. from Hartley et al. (2006) Ecology Letters.

Global distribution of Argentine ants against a backdrop of mean daily temperature of the coldest month (excluding urban records).

Collaborators: Phil Lester, Richard Harris