Whales Home > About Antarctica > Animals > Whales What is a whale? Whales belong to a diverse group of mammals called Cetaceans. Whale research Learn how non-lethal research is increasing our understanding of the complexity of the marine food web. Baleen whales & fisheries interactions There is undisputed evidence of human over-fishing, but no conclusive evidence that whales negatively affect fishery yields. Blue whale Blue whales are the largest animals ever known to have lived on Earth. Killer whale Killer whales (or orcas) prey on fish, squid, penguins, seals, dolphins, porpoises, and even other whales. Minke whale Minke whales are one of the smallest species of baleen whales. Humpback whale Humpback whales grow to about 15 metres long. They communicate with their famous and beautiful song. Fin whale The fin whale grows to nearly 26 metres, making it the second largest whale. Sei whale Sei whales are possibly the fastest swimming baleen whales, having been clocked at 25km/h for an hour when chased by whalers. Southern right whale Southern right whales have a distinctly V-shaped blow. They may live to 60 or more years of age. This content was last updated 9 years ago on 26 April 2012.