Energetic variability in toothed whales and relationships with a changing marine environment
Vicki Hamilton

Authors

Vicki Hamilton¹, Karen Evans^1,2 and Mark Hindell¹

1. Institute for Marine and Antarctic Studies, University of Tasmania, Private Bag 129, Hobart, Tasmania 7001, Australia
2. CSIRO Marine and Atmospheric Research, GPO Box 1538, Hobart, Tasmania 7001, Australia

Abstract

Information on the biology of many marine mammal species in the Southern Hemisphere is sparse. The importance of addressing and identifying environmental change issues, such as the impacts of a changing climate on the distribution of species and prey resources, and the capacity for adaptation by marine mammals is recognised. To this end, there is a need for long-term cetacean environmental datasets for use in modelling studies for identifying interactions between management advice and the effects of variability in the marine environment. Here we describe a project that aims to provide insights into aspects of the responses of marine mammal species to climate mediated variation in the marine environment, and how these responses might vary into the future under changing climatic conditions. Using marine mammal teeth as multi-decadal archives of ecological information, relationships between variability in the marine environment and tooth growth, as an indicator of energy available for growth, and isotopic composition, as a reconstruction of past diet in marine mammals will be examined. Initially focusing on three pelagic cetacean species: the sperm whale (Physeter macrocephalus), the long-finned pilot whale (Globicephala melas) and the short-finned pilot whale (Globicephala macrorhynchus), this project will incorporate investigations of both taxonomic and geographic variability regionally across Australia and more broadly across the Southern Hemisphere. Statistical models developed will be used to investigate how future projections of oceanic conditions may influence energetic intake in each species and the potential for adaptation of these species under changing environmental conditions.