Solving a scientific mystery essential to conservation:
Where do whales go in winter?

Sperm whales and Mediterranean whales:
one of the last great scientific mysteries to be solved...

Whales and sperm whales have been the subject of sustained studies for a long time. Knowledge levels on these two species are high in some respects, but there is still a huge gap: where do these giants go and what do they do in winter? 
In general, whale and sperm whale research campaigns focus on the summer period, when whales are in the Ligurian Sea and weather conditions allow cetaceans to be monitored. We know, for example, that whales migrate North-South to the Ligurian Sea in summer. But 9 months of the life of large cetaceans are still completely beyond our knowledge.
However, the level of knowledge about these species with traditional techniques marks, through this significant gap, the failure of many years of effort, expeditions and research.

"Previous failures": 

For the detection and monitoring of large cetaceans, boats of a certain size are generally used, which allow work on the high seas with limited autonomy. This system is disproportionately expensive, inevitably intrusive and entirely dependent on weather conditions. Conducting intensive expeditions over two years, to obtain a time pattern, and to know life stories, for example, would trigger an enormous human cost and financial effort. A sperm whale expedition around the Balearic Islands costs about €14,000 per week. If we count at least two weeks of work, every other month, over a year, the overall budget is € 168,000. And all these efforts to obtain data of only 92 days (if the weather is favourable!!!!!).

A team of scientists at the forefront of their fields

Following this failure of knowledge in the Mediterranean, three world-renowned cetacean experts, pioneers in the study of fin whales and sperm whales, joined forces to conceptualize a study plan that avoids the obstacles encountered by their predecessors.
The idea seemed obvious to them to replace surface research with acoustic observation. 

  • Dr Luke Rendell is Professor of Biology at the University of Saint Andrews (UK).

  • Dr Manuel Castellote is a researcher at NOAA in Seattle (USA).

  • Dr Jose Maria Brotons is a bioacoustician and biologist specialising in cetaceans, Director of the Tursiops Association and former researcher at the General Directorate for Rural and Marine Affairs of the Balearic Islands (Spain). 

EAR : Ecological Acoustic Recording 

We have developed a solution to solve the great mystery of Mediterranean whales: Ecological Acoustic Recording (EAR). The acoustic behaviour of these large marine mammals allows them to be studied with precision, using autonomous recording instruments that are permanently immersed. In addition, they allow the identification and evaluation of the size of individuals in particular. 

L'EAR (Ecological Acoustic Recording) is an instrument designed for the periodic recording of underwater audio signals, and for storing them on a hard drive. Published scientific work based on EAR and the value of the data collected confirms that EAR is a powerful tool for studying cetaceans.

With a project to install up to 1,000 metres deep, 6 listening points permanently installed for 2 years, and 1 year of data analysis, we will finally be able to solve a mystery that has never been answered: where do Mediterranean whales hide in winter?

An international scientific impact

The results obtained will have a remarkable impact on the scientific community, as they will be published in at least four prestigious scientific journals, such as Marine Mammal Science, Marine Ecology Progress Series, Biological Conservation, Aquatic Conservation, Endangered Species Research, where members of the scientific team responsible for the project have already published.

In addition, the results will be presented at international scientific gatherings, such as the European Cetacean Society-ECS and the Society for Marine Mammalogy congresses. Furthermore, we will provide data to national and international institutions in charge of the conservation of Mediterranean cetaceans.

This study will have a highly significant and lasting impact on the knowledge and conservation of Mediterranean marine mammals. The Balearic Islands, the starting point for the deployment of EAR listening.