When gray whale moms and their newborn calves head to the Alaskan feeding grounds, the calves play around and do other interesting things like solicit nursing. Here we see half of the mom's tail flukes in the air. If you look closer, to the right, you'll see "junior's" tail fluke tip too.
From 2018 04-15 SB Coast
Humpback tail flukes. From the HappyWhale database: Stump, CRC-12083 has been known since 2005, appearing to be a yearling when first photographed during the SPLASH project, and has been seen many times since by Channel Islands National Marine Sanctuary naturalists. Thought to be a female, she was seen with a calf in 2013 and 2014, thought to be mother of Top Notch.