Description as at the source:  
Personal headcanon as I’m trying to get back into the groove of drawing, sorry I’ve hit a serious slump. I see people redesigning the mane cast and other characters all the time design wise, but not often genetically, and I don’t just mean height and weight or species.
 
I like to see Coloratura as part hippogriff, a very weak amount in her blood stream as I imagine she would still look pony enough to come off as completely earth pony. It’s barely noticible on land, asides from fluffier ears, an excess of feathers around the chest, shoulders and back and sort of feather tips. However, in the water, she is almost completely sea pony. I decided against putting her cutiemark on the sort of dorsal fin on her tail, as it always looked silly to me in canon, and opted instead to use the colors from her cutie mark to liven her scales and feathers. Her necklace is not the sort of (transformation shell pearl necklace thing?) most hippogriffs wear, instead just an old gift from her camp days with applejack. In my headcanon, those necklaces are not really the key to their transformations but just common hippogriff accesories, as they change from seapony to birdpony based on how submerged in air or water their bodies are.