Most populations of humpback whales are no longer on the United States endangered species list thanks to international conservation efforts, the National Oceanic and Atmospheric Administration announced Tuesday.
Four decades of national and international initiatives to protect and conserve the marine mammals have helped nine of 14 humpback population segments rebound from historically low levels.
"Today's news is a true ecological success story," said Eileen Sobeck, assistant NOAA administrator for fisheries.
"Whales, including the humpback, serve an important role in our marine environment. Separately managing humpback whale populations that are largely independent of each other allows us to tailor conservation approaches for each population."
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After commercial whaling severely reduced populations, the US listed all humpback whales as endangered in 1970. Today, just four whale groups remain on that list, and one is now listed as threatened.
The International Whaling Commission's whaling moratorium imposed in 1982 -- which remains in effect -- played a crucial part in the comeback, NOAA said.
The US Marine Mammal Protection Act that protects marine mammals within US waters still applies to all humpback whales, regardless of endangered status.
The MMPA prohibits the killing of certain marine mammals in US waters and by US citizens on the high seas, and bans their importation into the United States.
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