The importance of whale-watching in the Algarve: contributions towards an environmentally sustainable activity

• Main Author: Pestana, Rafaela Alexandra Pereira
• Other Authors: Eira, Catarina Isabel da Costa Simões
• Format: Master Thesis
• Language: English
• Published: 2022
• Subjects: Cetaceans; Whale-watching; Noise pollution; Sustainable management; Portugal; Balaenoptera acutorostrata
• Online Access: http://hdl.handle.net/10773/36408

Whale-watching (WW), has evolved exponentially around the world, becoming an economically important activity for various regions. Several researchers debate whether or not this progression in the activity is another possible disturbance or even a threat to cetaceans with both positive and negative arguments. On the southern coast of the Algarve, the study area of this work, there has been an increase in the number of companies and vessels doing this activity. In this study, reports made by whale-watching companies between the years 2007 and 2021 were analysed (n=92), as well as their licensing forms (n=401). However, a survey directed at whale-watching companies was also developed during the present study, due to the low number of available reports. In order to characterise the activity and the fleet of this region, several parameters were considered, including vessel types, number of sightings, observed species, number of trips, number of passengers and possible direct income of this activity in this region. In the Algarve, the majority of boats are Rigid-Hulled Inflatable Boat (RHIB), between 5 to 10 meters-long with a passenger capacity of 10 to 16 people. Fleet characterization is extremely important since different types of boats produce more or less noise. Cetaceans use vocalizations to communicate, navigate, and feed among other functions and therefore they are affected by noise pollution in the ocean. Therefore, it is necessary to understand what vessel type is the impacting possible for whale-watching observations. Data from the companies' reports revealed that common dolphins (Delphinus delphis) are the most frequently detected Odontoceti and minke whales (Balaenoptera acutorostrata) are the most often observed Mysticeti. This work allowed the detection of gaps and the definition of a list of necessary studies to characterize the whale-watching activity in southern Portugal and a list of recommendations to make this activity in Portugal´s mainland compatible with the protection of the target species. ...