Meeting Abstract

10.2  Saturday, Jan. 4 08:15  Selective cannibalism: “Don’t eat me, I’m infectious!” PULPITEL, T.J.*; SIMPSON, S.J.; PONTON, F; University of Sydney, N.S.W, Australia; University of Sydney, N.S.W, Australia; University of Sydney, N.S.W, Australia tamara.pulpitel@sydney.edu.au

Uncovering the links between nutrition, cannibalism and locust migration has been a major step forward in developing a better understanding of the biology and population dynamics of the Australian plague locust, Chortoicetes terminifera. Limiting resources within crowded migratory bands often leads to mass cannibalism, where locusts seek to satisfy protein and salt deficiencies by turning to an alternative nutrient source; each other. As with most predator-prey interactions vulnerable locusts, whether young, small or injured, are generally first to fall victim to cannibalism. While such victims are easy to catch, targeting the weak may not always be the safest way of obtaining a meal. As with any food item, locusts must assess food quality prior to consumption of their conspecifics. Indeed, victims harbouring pathogens or disease may impose a higher risk of infection to the cannibal. Our research investigated whether cannibalistic locusts have the capacity to discriminate between fungal infected and non-infected victims. In a series of experiments, we used the acridid-specific fungus, Metarhizium acridium to identify whether starved locusts strategically avoid potential infection during cannibalism, while simultaneously satiating their protein appetites. This work gives a new appreciation of the costs associated with pathogen transfer through cannibalism. With a new grasp on how locusts weigh these infection costs against nutritional gain, we will present how cannibalism in locusts has facilitated our understanding of insect immune function and behaviour as well as implications for the management of this destructive pest species.