They were slaughtered for their blubber, and nearly wiped out in Brazil. Decades later, humpback whales are making a comeback.

• In the 1980s, thousands of humpback whales were slaughtered in Brazil for their blubber.
• After legal protections were introduced, they started repopulating, Reuters reported.

Humpback whales have made a comeback in Brazil decades after been nearly wiped out and slaughtered for their blubber, Reuters reported.

A few decades ago, a population of only 300 to 500 humpback whales survived in the country, scientist Jose Truda Palazzo, who works at the Humpback Whale Institute in the state of Bahia, told the news agency.

But in the 1980s, legal protections were put in place to prevent further killings, and since then, the whales have repopulated, with population size having grown to about 30,000 in 2022.

Many of the creatures are going back to their original breeding grounds along the coast, Palazzo added.

The population growth in humpback whales should be taken as a good sign for marine conservation not only in Brazil, but worldwide, Palazzo said.

"It shows that if we can do effective protection for marine species, most of them will recover," he said.

The effort to track the whale population is supported by "citizen scientists," non-professionals with a passion for science who support the work of the scientific community.

In the South-East of Brazil, the project "Baleia a Vista" was founded in 2015 by volunteers with the aim of reporting whale sightings.

"People became crazy, it's like an addiction. You became addicted to seeing the whales. This is my case," Julio Cardoso, one of the founders of the projects, told Reuters.