Oncorhynchus tshawytscha, commonly known as the Chinook salmon, is a species of fish found in the North Pacific Ocean and rivers that flow into it. This species is notable for its large size, with adults typically weighing between 10 to 50 pounds, and can grow up to 58 inches long. They are recognized for their distinctive coloration, which varies from blue-green on the back to silver on the sides, with black spots on their upper body. Chinook salmon are anadromous, meaning they are born in freshwater, migrate to the ocean, and return to freshwater to spawn. They play a crucial role in the ecosystem, serving as a food source for various predators, including bears and eagles. Their life cycle is vital for the health of both aquatic and terrestrial environments.