Humpback whales came close to extinction after being hunted for their oil and meat by whaling ships well through the middle of the 20th century. Commercial whaling of humpback whales was first regulated in 1946, by the International Convention for the Regulation of Whaling. In 1966, the International Whaling Commission prohibited commercial whaling of humpbacks. In 1970, they were listed as endangered under the Endangered Species Conservation Act. Recently, NOAA Fisheries announced that endangered humpback whales in nine of 14 newly identified distinct populations segments had recovered enough that they didn’t warrant listing under the Endangered Species Act. They said international conservation efforts to protect and conserve whales over the past 40 years had proved successful for most populations. Four of the distinct population segments are still protected as endangered, and one is now listed as threatened.
Humpback whales live in all major oceans from the equator to sub-polar latitudes. They weigh between 25-40 tons and are up to 60 feet in length. Their diet consists of krill, plankton and small fish; they can consume up to 3,000 pounds of food per day. The whales travel great distances during their seasonal migration, the farthest migration of any mammal. The longest recorded migration was 11,706 miles, with a trek from American Samoa to the Antarctic Peninsula. In the summer they are found in high latitude feeding grounds, such as the Gulf of Maine in the Atlantic and Gulf of Alaska in the Pacific. In the winter, they migrate to calving grounds in subtropical or tropical waters, such as the Dominican Republic in the Atlantic and the Hawaiian Islands in the Pacific. The humpback is a favorite of whale watchers for their aerial displays such as breaching where they jump out of the water, or slapping the surface with their fins, tails or heads.
The whales face many threats. They can become entangled in fishing gear, either swimming of with it or becoming anchored. Inadvertent ship strikes can injure or kill humpbacks. Whale watching vessels may stress or even strike the whales. Aquaculture, fisheries, and shipping channels, may occupy or destroy humpback whale aggregation areas. Recreational use of marine areas, including resort development and increased boat traffic, may displace whales that would normally use that area.
This new designation does not mean that whales will go unprotected. Humpback whales that breed in Central America in the winter and feed off California and the Pacific Northwest in the summer are among those that will remain on the endangered list because their population is estimated at only about 400 whales. Whales that breed of Mexico and feed off California, the Pacific Northwest and Alaska will be listed as threatened. There are about 3,200 of the whales in this group. In Alaska, there will be a mix because they have whales that breed in Hawaii and Mexico but also those that spend the winter in waters around Okinawa and the Philippines. These whales are endangered, and number only about 1,000.
“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.”
Picture courtesy of NOAA
