Marcelo E. Lagos, Craig R. White & Dustin J. Marshall
Invasive organisms often share characteristics that make them successful. Traits such as rapid growth and short generation times are classic ‘weedy’ adaptations that can make them successful outside their natural habitats. Given that invasive species often display ‘fast’ life histories, they may have relatively higher metabolic rates, but systematic tests across taxa are lacking. We compared metabolic rate across several sessile invasive and native invertebrates from marine habitats near Melbourne, Australia. We also investigated the influence of body shape (erect versus flat species) on the metabolic rate of these species, since growth form can also affect metabolic rate. For species with an erect growth form (for example tubeworms, solitary sea squirts and arborescent bryozoans), we found an effect of invasive status on mass-specific metabolic rate. Invasive species had much higher mass-specific metabolic rates than native species and this was particularly pronounced for organisms with smaller body masses. Given that smaller-bodied invasive organisms are typically ‘fugitive’ species, a higher metabolic rate may allow a faster pace of life, enhancing their capacity to invade and reproduce in newly created disturbed habitats.
Image caption: Bugula flabelata, one of the species used in this research inside metabolic chambers.