An adult male gray whale can grow to 14.6 m in length - that's longer than a city bus.
Females are slightly bigger.
Both males and females weigh up to 30,000 kg. These big animals eat large quantities of tiny animals. Scientists think an adult gray whale consumes about 1,200 kg of food per day. The main component of their diet is small, shrimp-like animals called amphipods that live on muddy ocean floors. Amphipods are tiny compared to gray whales.