Blue Whale

General information
Quick Facts
Order Cetacea
Suborder Mysticeti
Family Balaenidae
Species musculus
Status Endangered
Weight 150 tons
Diet Primarily Krill
Length 90 ft (average)
Home All oceans

Where Do Blue Whales Live?

How Long is a Blue Whale?

The Blue Whale (Balaenoptera musculus), is the largest animal to have ever lived on Earth! Blue Whales are also one of the fastest whales. They can cruise at 10 mph and reach burst speeds of 30 mph. Blue Whales can reach a length of 90 to 110 feet and a weight of up to 150 tons (300,000 pounds). At birth calves are about 27 feet long and grow quickly consuming 100 gallons of milk a day. The diet of Blue Whales is made up of one of the smallest animals in the sea, krill. The whales engulf hundreds of gallons of water to strain the crustaceans through their baleen.

A Global Whale

Blue Whales are found in all the world’s oceans. There are distinct population areas around the globe of the Blue Whale with these groups sharing genetics and acoustic signatures. Within their group range, Blue Whales will seek warmer waters for breeding and calving and seek out colder areas for feeding. There are three main regions for the Blue Whale: North Atlantic, North Pacific, and the southern hemisphere. Areas that have distinct populations are the Sea of Cortez, Gulf of St. Lawrence, Southern Ocean, Indian Ocean, and California.

Since Blue Whales will inhabit the entire breadth of an ocean basin they must communicate over incredible distances. When the sea conditions are optimum whales can communicate over an entire ocean basin… as in the distance between Hawaii and California. The male Blue Whale demonstrates his “fitness” to females by having a loud and deep song. Females can determine and choose her mate by comparing these calls. Blue whales have the lowest frequency call of all the whales. Lower frequency sounds travel further in the ocean and can aid in maintaining social structures over vast distances.

Human Impact

The only predators of Blue Whales are humans and Orcas. In the 20th century alone there was over 300,000 killed due to whaling. The population is in recovery and averages 2,000 whales off California. In the southern ocean off Antarctica there only a few thousand whales, and thus they remain endangered. Blue Whales, along with other whale species, have been granted protection from commercial hunting by the International Whaling Commission (IWC) since 1946.

Conservation Information

Whalers began hunting blue whales after the invention of harpoon guns. The pre-whaling population of blue whales quickly fell from about 350,000 to 1,000 in the 1920s. Blue whales became so scarce by 1966 that the International Whaling Commission declared blue whales a protected species worldwide. The Endangered Species Act also protects blue whales.

The present population worldwide is estimated to be 15,000 whales; with 2,000 of these living in CA coastal waters. This is the largest concentration of blue whales.