• Blue whale (Balaenoptera musculus);
• Fin whale (Balaenoptera physalus);
• Sei whale (Balaenoptera borealis);
• Bryde's whale (Balaenoptera edeni);
• Humpback whale (Megaptera novaeangliae);
• Minke whale (Balaenoptera acutorostrata).

Although most whale species have been heavily exploited in the North Atlantic, stock identity, migration routes and calving grounds in this ocean are still poorly known.

There is also little information regarding trophic relations, processes influencing the ecology of the whales and the threats posed by human activities.

  In the past few years the development of regular cetacean research and the expansion of commercial whale watching demonstrated that the Azores is in the path of the northern migration of at least part of the populations of several rorqual species, during Spring and Summer.

All the six rorqual whale species present in the North Atlantic have been recorded in the Azores and five of them occur yearly (Bryde's whale is a tropical species that seems to be occasional in the Azores). 

During their stay in the Azores, rorqual whales are seen feeding and there is some evidence that it may be associated with topographic features such as the slope of the islands and seamounts.

Rorqual whales are an important group of predators, and their biomass consumption is considerable. Although substantial uncertainty exists concerning the degree to which whales influence the structure and dynamics of ocean ecosystems in top-down ways, these influences must be sizable and may be reflected throughout all the trophic levels (Springer et al. 2003). The processes influencing the ecology of rorqual whales are still poorly understood but seem to be related to prey availability and proper breeding habitat.

To answer some of these questions the Great Whales Satellite Telemetry Program was established, focusing on three of the rorqual species that are seen in the Azores: Blue whale (Balaenoptera musculus), Fin whale (Balaenoptera physalus) and Sei whale (Balaenoptera borealis).

The Great Whales Satellite Telemetry Program is part of a wider program for the study of the habitat use of pelagic great predators developed by the Department of Oceanoraphy and Fisheries (DOP) and the Centre of IMAR of the University of the Azores and aims to gain insight into the processes influencing rorqual ecology in the North Atlantic, through the understanding of how these animals use their habitat.