The waters off Pico and Faial are the classic grounds. The channel between the two islands has the deepest water closest to shore and is the preferred base for the spring migration; Pico's whaling museums and the lookout system give the context for what you are watching.

Sperm whales are resident year-round and are the archipelago's signature animal — social groups of females and calves at the surface between dives, and the tail fluke going vertical as they descend. Numbers rise in summer.

The spring passage in April and May is when the great migratory baleen whales come through: blue whales — the largest animals that have ever existed — along with fin and sei whales, feeding on the spring plankton bloom. This is a genuinely short window and the reason many people book specifically for those weeks.

The year-round dolphins include common, bottlenose, striped, Risso's and spotted, often in large fast pods, and several operators run in-water swims with them under permit.

The islands themselves add Cory's shearwaters nesting in the cliffs in their tens of thousands, calling eerily at night, and the endemic Azores bullfinch on São Miguel — one of Europe's rarest birds, found only in the Pico da Vara laurel forest.

Practicalities

São Miguel, Pico, Faial and Terceira all run whale trips; Pico and Faial are the specialists' choice. Direct flights reach São Miguel from Lisbon and several European cities, with inter-island flights and ferries onward.

Whale watching is regulated: boats must approach from behind at low speed, keep at least 50 metres away — more from mothers with calves — and no more than three boats may be near a group at a time, for a limited period. Choose an operator with a biologist aboard; the difference in what you learn is substantial.