Dolphins don't need a calendar to celebrate—but we do! National Dolphin Day, on April 14, reminds us to appreciate these smart and downright fascinating marine mammals. From leaping through waves to chatting in clicks and whistles, dolphins are all about social life. They often travel in pods and love to check out passing boats whenever they get the chance. But pollution and overfishing threaten their survival, and they need our help. National Dolphin Day is a chance to learn, take action, and—if you're lucky—see these creatures in their natural habitat.

Take the Atlantic spotted dolphin—the star of today's image—known for the spots on its body, which multiply and become denser with age. You'll find them in the warm temperate and tropical waters of the Atlantic, hunting fish in coordinated groups. Their speed and agility make them efficient hunters—and a thrill to watch. The United States is home to several species, including the bottlenose, common, Risso's, and spinner dolphins. Each species helps maintain the ocean's balance, highlighting the need to conserve their habitat.