Research dives deep to understand climate impacts on whales

A world-first research project aims to understand how ocean changes influence the recovery of whale populations in the southern hemisphere.

An international team of researchers from six countries including Australia aim to create a model for whale distributions under future climate-change scenarios and investigate changes influencing population status and conservation of humpback whales.

Professor Brendan Mackey, Director of the Griffith Climate Change Response Program and Co-Director of the Whales and Climate research

Professor Brendan Mackey, Director of the Griffith Climate Change Response Program and Co-Director of the Whales and Climate research, said the five-year research program would establish a fundamental understanding of how changing ocean conditions were influencing the recovery of humpback whale populations.

“The project will develop adaptation scenarios for advancing whale conservation policies and programs,” Professor Mackey said.

“Climate change is drastically altering ecosystems and our oceans are experiencing fast changes, affecting all marine life.”

He said the project will also lead to an improved understanding of the whales’ contribution to ocean productivity by fertilising the upper layers with their nutrient-rich waste and provide greater insight into the role they play as climate engineers, driving carbon out of the atmosphere and trapping it on the ocean floor.

The project comprises climate scientists, marine ecologists and oceanographers from Griffith University, South Africa’s Stellenbosch University, University of Cape Town and Cape Peninsula University of Technology, the Smithsonian Tropical Research Institute in Panama, the Universidade Federal do Rio Grande (Brazil), Pontific Catholic University of Ecuador and the CEQUA Foundation (Chile)

Griffith University with the Climate Change Response Program is leading the project, contributing expertise in coupled ocean modelling, whale movement and biology, climate change impacts, and natural resource management and conservation policy.

Dr Olaf Meynecke, a key whale researcher at the Griffith Centre for Coastal Management and manager of the project.

Whale researcher and manager of the project Dr Olaf Meynecke said many whale populations are in the process of recovering following over-exploitation by the whaling industry. However, whales are now facing another human-made problem, climate change.

“The latest research on whales and climate change around the world show increased strandings, entanglements, reduced calving and migration shifts which have partially been attributed to ocean warming,” Dr Meynecke said.

According to Professor Ken Findlay from the Cape Peninsula University of Technology, the project breaks new ground combining historic long-term datasets with future scenarios for multiple whale populations and regions in the Southern Hemisphere.

“The combination of these different data sets represents a powerful tool to understand changes in whale distributions, and will validate our models in this area,” said Professor Marcello Vichi, the leader of the modelling team from the University of Cape Town.

Professor Alakendra Roychoudhury of Stellenbosch University suggest that long-term and seasonal observations in the Southern Ocean have been vastly unexplored.

“A lack of such baseline data can skew climate models, creating uncertainties. For example, we recently used seasonal carbon dioxide fluxes to show that the Southern Ocean is behaving quite differently to what was previously thought based on climatology and satellite data alone,” said Professor Roychoudhury.

Diagram showing role whales and their nutrient rich faeces play in mitigating climate change and increasing ocean productivity.

The research teams from Brazil, Chile, Ecuador and Panama will investigate detailed movement of the South American west coast humpback whale population. During the austral summer, these populations migrate to feeding grounds in the cold waters of southern Chile and Antarctic Peninsula.

“The western Antarctic Peninsula has been experiencing a drastic increase in warming and there is strong evidence that this warming is affecting the whales’ ecosystem,” said Professor Eduardo Secchi, Federal University of Rio Grande.

“Our research assesses the effect this change is having on whale distribution and their recovery after the long period of exploitation in the first half of the 20th century.”

With the breeding season upon us, multiple research cruises are scheduled for the feeding and breeding grounds of target populations in Antarctic and coastlines of Australia, Africa, and South America, with migration models and project information available at the Whales and Climate Program.

/University Release. The material in this public release comes from the originating organization and may be of a point-in-time nature, edited for clarity, style and length. View in full here.