The whale had been seen earlier in the day floating near beaches in Rio’s western zone before ocean currents carried it to São Conrado.
Local authorities responded to the scene, but the cause of death has not yet been confirmed.
Humpback whales are regularly spotted along the coast of Rio between June and November, with peak sightings from July to September.
Each year, about 25,000 humpbacks migrate roughly 4,000 kilometres from Antarctic feeding areas to breeding grounds off northeast Brazil, mostly around the Abrolhos region, known for its coral reefs and marine biodiversity.
