Pacific whitesided dolphin beaks, the front edge of their dorsal fins, and their flukes and flippers are all dark. Pacific whitesided dolphins have a unique bicolored dorsal fin. All dolphins, including the Pacific whitesided dolphin, have strong eye muscles that can change the shape of the eye lens in order to focus in both air and water. Dolphins can recognize some colors and their pupils can adjust to light and dark changes in their environment. Dolphins have a well-developed sense of hearing and navigate their environments through echolocation .
Dolphins have very sensitive skin, which is easily damaged but also heals quickly.
Pacific whitesided dolphins are known to consume hake, anchovies, squid, and sardines. Pacific whitesided dolphins mate during the late summer and early fall. Female dolphins can bear a calf every two years but generally give birth every three years. No one really knows the average life span of a Pacific whitesided dolphin however, it is believed to be anywhere between 36 and 40 years. Pacific whitesided dolphins are sometimes preyed upon by killer whales , are caught incidentally in drift nets and gill-nets, and some countries harvest them for food.