A stunned onlooker captured a once-in-a-lifetime moment when she spotted a dog swimming out to sea and playing chase with a wild dolphin. Marcella Williams, 49, couldn’t believe her eyes when she saw the pooch off the coast, swimming in circles as it chased a dolphin's fin. According to Marcella, who lives in Belize City, Belize, she had been searching for fishing bait around 10 miles away from her home when she heard a dog barking out in the waters. Looking off the coast near Gallow's Point, Marcella then saw the dog's head bobbing, swimming around as it circled the dolphin. To Marcella's surprise, the dolphin seemed to enjoy the unique interaction, too. She then captured the moment on video to show her two children – before later posting it on social media so her friends and family could also witness the moment which immediately went viral.