1. Centre for Research into Ecological and Environmental Modelling; University of St Andrews; The Observatory, Buchanan Gardens St Andrews Fife KY16 9LZ UK
2. Statistics in Ecology, Environment and Conservation; Department of Statistical Sciences, and African Climate and Development Initiative; University of Cape Town; Rondebosch 7701 South Africa
3. Sea Mammal Research Unit; Scottish Oceans Institute; University of St Andrews; St Andrews Fife KY16 8LB UK
4. Centre for Invasion Biology; Department of Botany and Zoology; Stellenbosch University; Stellenbosch South Africa