Although people have long been fascinated by the behaviour of animals, the formal discipline of animal behaviour–ethology–is actually relatively new, dating to the work of Konrad Lorenz in Austria in the 1930s. The application of ethological principles and methods to the study of animal welfare is even newer. Behavioural data can offer insight into the potential impacts of human activity, such as tourism and fishing, on marine mammal populations and it is, therefore, necessary for understanding short-term and long-term changes at population levels for various Delphinidae species. Cetacean behaviours are divided into two different classes: long duration behaviours or states, in which the most common measure is the duration of this behaviour, and behavioural events, short duration behaviours in which the most common measure is the occurrence of each event.

Delphinus delphis leaping (behavioural event) photo by G. Pietroluongo.

The aim of this project is to classify the main behavioural states and events of the Aegean cetaceans, with a particular focus on a population of Common dolphin (Delphinus delphis) with a high site fidelity to Samos waters. The study area is located in the Aegean Sea, mostly in the North of Samos Island. This part of the island is rich in cetacean species but hasn’t been studied as much as in other areas around the Mediterranean Sea and, especially for the common dolphin, the behavioural data available is very poor. Furthermore, we will try to match the different behavioural states to the dolphins’ whistles collected by the Bioacoustics Team, in order to understand if the whistles’ frequency changes during specific behaviours.

BORIS screen

 

During the sightings from the boat, we record videos with a Sony Handycam camera, which are analysed
in order to understand all the states and events that
were seen and highlight the main group state as well as every single event spotted. Then the videos are
analysed with BORIS software, a tool used to help us in
determining the duration of the states and the occurrence of the events.

Video recording during a sighting, photo by L. Kessler

Up to date, we have analysed videos from June 2017 to June 2018, meaning we have gathered one year of data. Thanks to the bioacoustics team, we have been able to match the main behavioural states to the dolphins’ whistles from August 2017 to June 2018.

Sara Moscatelli, UNIVPM, università politecnica delle Marche, IT.