What do we know about dolphins visiting the Tagus estuary?  – Here I’m

What do we know about dolphins visiting the Tagus estuary? – Here I’m

The project for the Observatório Golfinhos no Tejo, officially presented today, is installed at the Maritime Traffic and Safety Coordination and Control Center of the Port of Lisbon (VTS Tower), in Algés, in the municipality of Oeiras, district of Lisbon, a privileged place to detect dolphins visiting the estuary.

The views, which began in March of this year, aim to fill the lack of studies on the presence of these animals in the Tagus estuary, taking into account that reports of sightings have increased in recent times.

Researchers want to know “which species come here, whether they are always the same animals or others, what they come to do here and what attracts them to the estuary,” explained Ana Henriques, of the Associação Natureza Portugal (ANP), associate in Portugal of the World Wide Fund for Nature (WWF).

There are still no answers to these questions, nor will there be any soon, because it is first necessary to analyze and study models based on the data collected, pointed out Ana Rita Luís, of the Center for Marine and Environmental Sciences (MARE) of ISPA-Instituto Universitário, noting that it will take at least a year of data and observations to arrive at the results.

However, in 19 days of observation (140 hours with continuous view) the dolphins visiting the Tagus were sighted in 40% of the days. Common dolphins were detected in all of these daily sightings, but bottlenose dolphins arrived on one of the days, he added.

The data on the presence of cetaceans are collected through continuous observation by groups of (for now) 12 volunteers, from the privileged point which is the VTS Tower, also recording human activities and atmospheric conditions, among other factors.

The observation of the volunteers is completed by an acoustic sensor that allows to collect the vocalizations of the animals (each dolphin emits unique vocalizations) and also by direct observation, with the boat approaching the animals, activities that count on the collaboration of the Faculty of Sciences of the University of Lisbon (FCUL).

This approach to visiting dolphins will allow, for example, to better understand the distinctive physical characteristics of each member of the group, i.e. the shape of their dorsal fin, which is also unique and distinctive of each animal.

The Observatory is part of the wider initiative entitled Dolphins in the Tagus, launched in June 2021, as part of the Oceano Azul Foundation’s Training Program for Non-Governmental Organizations (OMG).

The project will also publish, on 4 July, a report that will gather existing knowledge about the estuary, currently dispersed by numerous reports and studies, focusing on its potential for dolphin visits.

The information gathered from the observations – which will take place at least until the end of 2022 – will be used for the development of academic theses, scientific articles and other popular science works, as well as serving as a basis for wider public disclosure, in particular to those who live in the metropolitan area of ​​Lisbon.

The project is carried out in collaboration with APL – Administration of the port of Lisbon, ANP | WWF, MARE – Center for marine and environmental sciences and ISPA – University institute of psychological, social and life sciences.