Azores delphis project was started in July 2020 with the overarching PhD of Fadia Al Abbar who is looking at "Social mitigation strategies of common dolphins" off the coast of Sao Miguel, Azores. Besides this PhD project we aim to understand more about the local population, site fidelity, and their interaction with whale-watching activities. We are using a drone, photo ID, acoustics, and land observations. Msc students and volunteers have played a large role in the data collection and in the data analysis. We have completed 1 feasibility study in 2020, 2 full fieldwork seasons in 2021 and 2022, and a supplementary field-season in 2023. We are currently in the data analysis phase of the project, and expect to have result in 2024/2025.
PhD Fadia Al Abbar 2020-Current
Common dolphins' (Delphinus delphis) social mitigation of tourism-induced disturbance
On the Azores, swimming with dolphins (SWD) in the wild is most often done with short-beaked common dolphins (Delphinus delphis). Swimming with common dolphins is unusual anywhere else in the world, because their high-activity state makes it a challenge. Therefore, the SWD effect on these larger gregarious groups remains understudied.
Additionally, the Azores may be a potential nursing ground, which makes them particularly vulnerable to disturbance. It is therefore important to study their population and age-class structure to identify the peak season of neonates and calves. Lastly, pods that have had long-term exposure to SWD activities may have found creative tactics to cope with disturbance.
What we currently know about the common dolphins in the Azores is that there is a behavioural effect of whale watching and swimming with dolphin activities done by Arianna Cecchetti. To read her PhD thesis click here.
However, the knowledge of the behaviour of common dolphins is still in its early stages, hence the start of this project, to learn and understand more.
Msc. thesis Bianca Vaz 2023
Delphinus delphis responses to whale-watching tourism: boat approach and swimming interactions in S. Miguel, Azores
Msc. thesis Anne Lodder 2022
Calculating the position and movement of common dolphins from moving drone videos
Msc. thesis Maria Rosas Corona 2022
The effect of tourist vessel manoeuvres on the behaviour of common dolphins (Delphinus delphis) with mother-calf pairs in São Miguel Island, Azores, Portugal.
Msc. thesis Luana Clementino 2021
Tourism-induced communication changes in common dolphins of the Azores
Msc. thesis Anne Grundlehner 2021
An aerial perspective on pod organization in common dolphins (Delphinus delphis): calves as a risk-related variable?
Prior to this project, Laura Gonzalez and Fadia Al Abbar set up a common dolphin photo ID catalog at Futurismo Azores Whale Watching.
Photo ID of common dolphins is quite a challenging task and a public catalog has not been created for the Azores archipelago yet. Dolphins aggregate in large numbers, some of them do not present any mark on their fin to be distinguished from each other, and such marks can be hard to detect, especially from a picture of fast swimming dolphin taken from a moving vessel! However, several studies (e.g Hupman 2016, Pawley et al., 2018) have proven photo-ID of common dolphins using markings and pigmentation to be successful.
Due to the use of an opportunistic platform (whale-watching boats), we chose to focus on collecting data on individuals with obvious markings that we called “highly identifiable individuals”. These have been defined as a category of “highly distinctive nicks/notches” and/or “high pigmentation” of the left side of the dorsal fin. The photos have been collected between 2018 and 2019.
Preliminary results show a presence of common dolphins year-round, with larger groups in summer months. Several “highly identifiable individuals” have been re-sighted in the months of July and August 2018. These results may indicate a return-rate of certain common dolphins within the same season around São Miguel. This method of analyzing only the “highly identifiable individuals” aims to improve the data collection of the common dolphins by concentrating the effort on obvious individuals from an opportunistic platform, as there is limited time spent with the species.
We will continue to collect and analyze the photo ID of common dolphins in the next years, see the link below to read our preliminary results of the published poster at the World Marine Mammal Conference in Barcelona, Spain.