The anticipation is palpable aboard the Boaventura II as the yacht departs Rio de Janeiro at sunrise. Once the vessel clears the Cagarras Islands, rocky outcrops situated just three miles off Ipanema beach, passengers gather at the bow, scanning the horizon. They do not have to wait long before the excitement begins. “Eleven o’clock!” someone calls out, as a pod of bottlenose dolphins appears, playfully diving in and out of the water. Moments later, two distinct spouts of vapour hanging in the air signal the primary objective of the excursion: a group of humpback whales.
This experience has become a bucket-list moment for many, heightened by the spectacular backdrop of Rio’s jungle-cloaked mountains. Such sightings have become increasingly common as Brazil’s humpback whales return to the shores of the Atlantic metropolis. This year, a whale has even been repeatedly spotted within Rio’s Guanabara Bay. These sightings, numbering at least 18, are a first and have sparked significant speculation among experts that humpbacks are reclaiming areas they occupied centuries ago.
“You can’t put a price on this show. It’s pure magic,” says the yacht’s skipper, Theo Andrade, co-founder of the tour agency ROC Sail. After working on whale-watching expeditions around breeding grounds further north, Andrade established his own operation in Rio to share these encounters. Luciane dos Santos, a 53-year-old passenger, is fascinated by the gentle giants and took a day away from her busy life running a drinks wholesaler in the hopes of catching a glimpse of them. “I’m amazed at how a 50-tonne animal can perform such a beautiful leap that leaves everyone spellbound,” she remarks.
She was not disappointed by the encounter. “I feel a sense of fullness – it’s truly a gift from nature,” says Dos Santos, after a morning spent admiring six humpbacks performing their aquatic ballet. Humpbacks have historically travelled along the Brazilian coast between June and November, migrating from feeding grounds near South Georgia and the Sandwich Islands in the South Atlantic to the warmer, shallower waters of the Abrolhos Bank for breeding and calving.
The history of these whales in the region is marked by tragedy. Indiscriminate hunting, recorded as early as 1780 in Rio by the artist Leandro Joaquim, who painted scenes of whales being chased and harpooned in Guanabara Bay, decimated the population by the time a global ban on commercial whaling was implemented. “At the end of the 1980s, fewer than 1,000 individuals were counted in this Brazilian group. Today, there are nearly 30,000,” says Thiago Ferrari, director of the Amigos da Jubarte (Friends of the Humpback) conservation project. Other estimates suggest the population may be closer to 35,000.
While Brazilian waters host several species, including the once-endangered southern right whale and Bryde’s whale, the 15-metre-long humpback remains the star of the show due to its acrobatic performances. Liliane Lodi, a marine biologist with the Ilhas do Rio (Islands of Rio) research project, first registered a humpback whale in the city’s waters in 2014. Since then, the number of sightings has soared, bringing both joy and new challenges to the region.
“Rio de Janeiro is an area of passage; it’s a migration route,” Lodi explains. “However, we have already registered behaviour that is typical of breeding grounds, rather than passage areas.” This shift includes the spotting of newborn calves, displays of competitive behaviour between males, and recordings of haunting whale songs. These observations suggest that the whales are increasingly using the area for more than just transit.
To manage this influx, the Amigos da Jubarte non-profit organisation offers free training courses in partnership with local authorities. They have already certified about 20 agencies for cetacean watching in Rio, including ROC Sail. Having a researcher onboard is considered fundamental for healthy, sustainable, and orderly whale-watching tourism. During trips, biologists like Bueno monitor the activity, ensuring skippers follow best practices, such as maintaining a distance of at least 100 metres and limiting observation time to 30 minutes per group.
“Surveying the number of individuals allows us to track population growth and individual behaviour,” says Bueno, who meticulously records data during every excursion. Despite these efforts, the environment remains precarious. “Fishing, tourism, large ships, chemical pollution and noise pollution, these are all challenges and threats,” she adds. The cumulative impact of human activity is a primary concern for those monitoring the recovery.
The challenge lies in ensuring that the booming tourism industry does not undermine the conservation gains. “For a whale, it doesn’t make much difference that one operator follows best practice if the others aren’t doing so,” Lodi notes. As the humpbacks continue to return to the waters of Rio, the balance between economic opportunity and the protection of these massive, majestic creatures remains a delicate, ongoing negotiation. The report also notes that “It’s very sociable when it wants to be,” says Lodi, who enlisted the help of citizen scientists to study the animal. The report also notes that clipboard in hand, Bueno answers tourists’ questions, advises the skipper to ensure that he follows best practice – such as keeping at least 100 metres from the whales and never spending more than 30 minutes near the sam. The report also notes that before revealing the underside of their fluke as they dive back underwater, the majestic mammals surface to breathe with an unhurried chuff. The report also notes that as elsewhere, indiscriminate hunting – recorded as early as about 1780 in Rio by the artist Leandro Joaquim, who painted scenes of whales being chased and harpooned in Guanabara Bay – had decimated the population by the time a global ban on commercial whaling took effect in 1986. The report also notes that as well as a new source of tourism revenue during the winter, such collaboration between science and leisure is one of the reasons advocates believe Rio’s budding whalewatching industry can be a tool for conservation. The report also notes that mariana Bueno is an environmental sciences student employed by ROC Sail to accompany each whalewatching outing on the Boaventura II. The report also notes that clipboard in hand, Bueno answers tourists’ questions, advises the skipper to ensure that he follows best practice – such as keeping at least 100 metres from the whales and never spending more than 30 minutes near the same individuals – and writes down details of every sighting. The report also notes that these behavioural surveys then serve as the basis for formulating laws and rules.”.
