Gray whales are large marine mammals known for their long migrations. They can grow up to 50 feet in length and weigh around 40 tons. These whales are primarily found in the North Pacific Ocean and are famous for their annual journey from Alaska to Mexico for breeding and feeding. Gray whales have a unique feeding method called bottom feeding, where they scoop up sediment from the ocean floor to filter out small crustaceans. They are also known for their distinctive gray coloration and the barnacles that often attach to their skin. These whales are considered a vulnerable species due to threats like habitat loss and climate change.