Fisherman, Marcos Carramao de Farias, spotted a baby dolphin trapped in a plastic bag off the coast of Sao Paulo, Brazil. After he and a fellow angler helped free the dolphin, it gives a happy little dance in the water that can easily be interpreted as an ecstatic "thank you."
In Laguna, Brazil, dolphins herd fish toward fishermen on the beach and then signal them when to toss their nets. The dolphins then get to feast on the fish that are not caught. This is an untrained behavior and has been going on since the mid 1800's.
In a story that can be adapted for another Flipper sequel or reboot, rescuers are trying to save a dolphin that's stranded in wetlands along the California coast. It's difficult to tell whether the dolphin just doesn't know how to get back to the open waters of the ocean, or if it's trying get a plum role in an episode of How I Met Your Mother.