The Ocean is very, very large... bigger than all the land. Whales are very big, but the biggest ones are only about as big as a house, and other kinds are smaller than that, so the Ocean, which is much, much bigger than that can fit them just fine.
There is no ocean that has the most whales all year. Because whales migrate, at certain times of the year the Indian ocean or the Southern ocean will have the most whales. The most species of whales are found in the Southern ocean.
Deep ocean is the whales favorite habitat.
No whales prefer open ocean, not caves.
the Atlantic Ocean
Orcas, also known as killer whales, are the main predators of whales in the ocean ecosystem.
megalondon's eat anything in the ocean that can fit into there or that they can see moving for example: whales any species of fish turtles
blue whales live all over the world (but in the ocean of course)
Blue whales are normally found in the sunlight zone, which is the uppermost layer of the ocean.
Killer whales stay in the ocean.
There are whales in the ocean off the coast of Alaska.
The only whales that do not live in the ocean, are the ones found in captivity. Killer whales (or Orcas as they are commonly known), and Beluga whales are common in theme parks.
Grey whales might not fit into the new habitat, although they have been there as recent as the 1700's. They have been extinct there, and new species might have replaced their absence.