When scientists study humpback whales near Antarctica, their job is made considerably easier by the animals themselves who swim alongside boats in curiosity.

In recent years, this task has become even easier.

That’s because humpback whales are making a significant comeback after being pushed to the point of extinction, according to the New York Times.

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Throughout much of the 19th and 20th centuries, humpback whales were relentlessly hunted. By 1980, humpback populations were estimated to be 10% of their pre-hunting levels.

When the magnitude of the humpback crisis was realized, countries began banning whaling, enforcing multinational treaties against their slaughter.

Since then, populations have recovered, the New York Times reports.

A team of scientists led by Ari Friedlaender, a researcher at the University of California Santa Cruz, went to verify this claim.

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Between 2010 and 2016, they used darts to collect small samples of skin and blubber from humpbacks around the Western Antarctica Peninsula.

DNA sequencing was employed to ensure that the samples came from unique animals.

More than 60% of the females tracked had high progesterone levels, a sign of pregnancy, which suggests that the whales are reproducing at a rapid pace.

It’s a tale that defies the prevailing trend in conservation news.

Many scientists believe that climate change is precipitating the 6th wave of mass extinction.

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In a study published in the Proceedings of the National Academy of Sciences, a team of researchers argue that a “biological annihilation” is underway that represents a “frightening assault on the foundations of human civilisation.”

“The situation has become so bad it would not be ethical not to use strong language,” Gerardo Ceballos, lead author of the study, told The Guardian.

The team studied species across the animal kingdom and found that billions of regional populations have been lost and that 50% of all individual animals have died in recent decades.

Humpback whales are not immune to these broader ecological trends.

The species depend on tiny krill, an animal that’s being affected by both new forms of fishing and the rise of climate change.

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Krill feed under ice sheets, so as ice melts, krill have fewer places to find food. Similarly, as ice melts, massive trawling boats have new opportunities for harvesting krill.

If krill species plummet and disappear, then entire marine ecosystem would collapse, according to the Guardian.

But for the time being, humpbacks are on the upswing and that’s cause for celebration.

Global Citizen campaigns on the United Nations’ Global Goals, which call on countries to protect ecosystems. You can take action on this issue here.