Mammals are warm- blooded animals that feed their young on milk. Most of them live on land but some, the marine mammals, live in the sea. Marine mammals include whales, dolphins, seals, sea lions and walruses. All of them breathe air but have adapted to life in the sea, having flippers instead of legs, for example.
The blue whale is the biggest animal that has ever lived. Its heart is as big as a car an its tongue weighs as much as an elephant. The biggest ever measured was 33.5m long
Killer whales, or orcas, live and hunt in groups called pods. By working together, they can overpower and kill much larger whales. Some orcas hunt small prey like seals and fish
Like most large whales, humpbacks feed on small fish and shrimp-like krill. They trap whole shoals inside their mouths behind plates of baleen, which hang down from their upper jaws.
Most large whales are rare, because in the past they were hunted. Whalers killed them for their meat, considered a delicacy in some countries. It is now illegal to hunt most large whales, and the huge whaling fleets that once sailed the seas are a thing of the past.
Like whales, dolphins belong to the mammal group called cetaceans. Dolphins use echolocation to find food, making loud clicks, then listening for echoes that bounce back. They often work together to round up prey.
Seals eat fish, but they haul themselves out onto ice or land to rest and to give
birth to their young. Baby harp seals are born with white coats. Their mothers’ milk is very thick and creamy
The walrus lives in the Arctic ocean, which surrounds the North Pole. It feeds on shellfish, which it collects from the seabed. All walruses have long tusks, although those of the males are bigger. They use these to spar for mates and also to defend themselves from polar bears. Walruses live together in large groups.
Quiz Questions on Marine Mammals
- What is the biggest animal on earth: the elephant or the blue whale?
Answer: The blue whale
- Do seals eat fish or seaweed?
- By what name are orcas more commonly known: killer whales or seals?
Answer: Killer whales
- Baby harp seals are born with grey True or false?
- Which use echolocation to find their prey: dolphins or walruses?
- What ‘K’ are shrimp-like creatures that humpback whales eat? Answer: Krill
- Seals give birth in the True or false?
Answer: False (they give birth on ice or land)
- Do all walruses have tusks, or only the males?
Answer: All walruses have tusks
- What ‘P’ is a group of killer whales known as?
Answer: A pod
- Why are many large whales rare today?
Answer: Because in the past they were hunted
- Which marine mammals sometimes kill and eat whales that are larger than they are?
Answer: Killer whales (orcas)
- Do all whales eat large animals?
Answer: No (some eat small prey)
- Which ocean surrounds the North Pole?
Answer: The Arctic ocean
- What’S’ do walruses eat?
- Where on a whale would you find its baleen?
Answer: Inside its mouth
- What ‘C’ is the name of the marine mammal group that contains whales and dolphins?
- Near which pole do walruses live: the North or the South Pole?
Answer: The North Pole
- What part of a blue whale weighs as much as an elephant?
Answer: Its tongue
- How long was the largest blue whale ever measured?
Answer: 33.5m long
20. Are dolphins mammals ?
Answer: Yes, Cetaceans