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 primarily feed on small organisms like amphipods, which they filter from the ocean floor using their baleen plates. Every year, gray whales migrate between their feeding grounds in the Arctic and breeding grounds in Baja California. This journey can cover over 10,000 miles, making it one of the longest migrations of any mammal. Gray whales are also known for their unique gray coloration and the barnacles that often attach to their skin.