South American sea lions are generally of medium size, with adult males can reach the length of more than 2 meters and females can reach the length of 1.6 to 1.7 meters. North American sea lions are one of the largest of the sea lions. They gentle and like to gather together. They can form a large group of thousands in the wild beach area. Their vision is poor, but their hearing and smell are very sensitive. Sea lions are black when they are born and can live an average of more than 20 years. Sea lions are very social animals, and they have a variety of communication methods. They hunt in the sea during the day, occasionally climb to the shore to bask in the sun, and sleep on the shore at night. They have no permanent resting place except the breeding season, and generally rest in places with plenty of food. They eat a lot, so they spend most of the day hunting to satisfy their voracious appetites, and they usually feed on fish, squid, jellyfish.