A new study has designed a prediction method to simulate the yearly southward migration of humpback whales, which could provide management authorities with greater awareness of altered migration routes in a changing climate.
Led by Griffith University, the study focused on the southern migration of humpback whale mums and calves between the Great Barrier Reef and the Gold Coast bay to develop a new modelling approach to predicting their movements.
“Humpback whales encounter a variety of environmental conditions during seasonal migration between polar feeding grounds and tropical breeding grounds,” said lead author Dr Jasper de Bie, from Griffith’s Coastal and Marine Research Centre.
“The relationships between environmental conditions and the whales’ migratory movements are largely unknown because there is a lack of oceanographic data coupled with the presence or absence of the whales.”
Dr De Bie and the team reproduced observed migration patterns from August to October 2017 by assessing how the sea depth, ocean currents and water temperatures impacted the whales’ movements.
The modelling further confirmed that the whales switched direction after Hervey Bay (a known resting ground), which appeared to align with the coastline.
“Our model provides a novel, suitable framework for simulating humpback whale migration, and an important first step in the development of predictive models of humpback whale behaviour,” Dr De Bie said.
“Developing such tools is increasingly necessary to predict how changing ocean conditions are likely to affect their distribution.”
The paper ‘Agent-based modelling of southward coastal migration by humpback whale mother-calf pods off eastern Australia’has been published in Marine Mammal Science.
