The US government is considering taking the humpback whale off the endangered species list in response to data showing the population of the massive marine mammal has been steadily growing in recent decades.

Known for their acrobatic leaps from the sea and complex singing patterns, humpback whales were nearly hunted to extinction for their oil and meat by industrial-sized whaling ships well through the middle of the 20th century. But the species has been bouncing back since an international ban on their commercial whaling in 1966.

"Humpbacks by and large are an example of a species that in most places seems to be doing very well, despite our earlier efforts to exterminate them," said Phillip Clapham, a senior whale biologist with the National Oceanic and Atmospheric Administration (NOAA).

The US government is required by law to review the endangered species status of an animal or plant if it receives "significant new information". The National Marine Fisheries Service, a NOAA agency, received results last year from an extensive study showing that the north Pacific humpback population has been growing 4-7% a year in recent decades.

Public comment is being accepted until 13 October on the upcoming review, which is expected to take less than a year. It is the first review for humpbacks since 1999.

A panel of scientists will then study the data and report on their analysis in late spring or early summer. It is unclear what the decision on delisting the humpback will be.

Some environmental groups are already opposing the possibility of a delisting.

Miyoko Sakashita, the ocean programs director at the Center for Biological Diversity, said that ongoing climate change and ocean acidification are emerging threats that may hurt humpback whales.

"Ocean conditions are changing so rapidly right now that it would probably be hasty to delist the humpbacks," Sakashita said.

Ralph Reeves, who chairs the cetacean specialist group at the International Union for the Conservation of Nature (IUCN), said the US should remove humpbacks from the list if populations have sufficiently recovered.

He said conservationists must "be prepared and willing to embrace success" if they're to maintain what he called a "meaningful" endangered species program.

"The whole process, the credibility of it, depends on telling people that things are really bad when they're really bad and telling people that they aren't so bad when they aren't so bad," Reeves said.

There are an estimated 18,000-20,000 humpbacks in the north Pacific, up from just 1,400 in the mid-1960s. A survey in the early 1990s of humpbacks in the north Atlantic showed the population at 10,600. The results of a follow-up to that study, expected by the end of the year, are likely to show this population has grown, too.

The global humpback population is estimated to be about 60,000, according to the Swiss-based Conservation of Nature union.