SALVADOR, Brazil — The humpback whale population off Brazil's coast has grown roughly 27-fold since commercial whaling ended, driving a surge in whale-watching tourism along the Bahia and Espírito Santo coastlines. The rebound represents one of the most striking marine recoveries in the South Atlantic.

The western South Atlantic humpback population, which feeds in Antarctic waters and breeds off Brazil, fell to a few hundred animals by the 1950s after decades of industrial whaling. Researchers with the Instituto Baleia Jubarte, based in Caravelas, Bahia, have documented a rebound to tens of thousands as the whales return to the Abrolhos Bank each austral winter.

The recovery has reshaped local economies during the July-to-November breeding season. Boat operators around Praia do Forte and Vitória report rising bookings, while tour guides say sightings of mothers and calves near the Abrolhos Marine National Park have become routine, attracting both domestic and foreign tourists.

Marine biologists cautioned that the growing traffic of tourist vessels requires stricter oversight to avoid disturbing the animals. Ibama, Brazil's environmental agency, has promoted approach guidelines that limit how close boats may travel and how long they may remain near the whales.

Researchers framed the rebound as evidence that the 1986 international moratorium on commercial whaling delivered measurable results decades later. Continued monitoring will be needed to track the population as it approaches pre-whaling levels.