North Pacific humpbacks come to Alaska to feed on our sea's riches. Humpbacks are baleen whales. They have a plate of keratin, or baleen, attached to the upper jaw, which works like a strainer to catch their food. They have no teeth, so they can eat only the tiniest of seafood.
The waters around Juneau are rich in krill (shrimp-like organisms) and small baitfish, humpbacks' favorite food. Adult humpbacks may eat a ton of food per day.
Humpbacks migrate more than 3,000 miles from tropical waters, like Hawaii, to the cooler waters of Southeast Alaska in as few as 30 days.
Baleen whales do not live in family groups, but often gather into small feeding concentrations. Groups of humpbacks often cooperate in a feeding behavior known as "bubble-net feeding," a unique, spectacular activity. The whales circle a ball of krill, then surge up from underneath the ball to the surface, engulfing huge mouthfuls of the crustaceans.
There are about 13,000 humpback whales in the world today, 10 to 15 percent of the pre-whaling population. About 750 humpbacks visit Southeast Alaska during the summer months, a few of which stay year-round.
Revered king of the ocean and an important character in Northwest Native culture, the orca, or killer whale, is a skillful predator and will eat a variety of prey, including swimming moose and other whales. Orcas have attacked and killed great white sharks. There are, however, no documented attacks on humans in the ocean. They have no natural predators.
Males reach lengths of up to 25 feet and weigh up to nine tons, females up to 20 feet and eight tons. Males have dorsal fins up 6-feet-tall, differentiating them from females, which have shorter, more curved dorsal fins.
Orcas live in family units called pods and usually remain with their pod for life. Each pod has its own "language" or dialect.
Orcas are broken down into two basic sub-groups: residents, which feed primarily on fish, and transients, which feed on marine mammals. Resident pods are usually much larger, often seen in groups called super pods, which may have 150 members. Transient pods are normally groups of five to 10 animals.
Orcas are nomadic, often traveling as far as 100 miles a day. They may be seen in one area for a month, then disappear for several weeks.
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