These are Julia butterflies and they have been photographed drinking the tears from turtles in Ecuador. These butterflies like to drink tears from other animals to get some of the nutrients and salt that they need. This is a form of mud-puddling, the adorably named behavior of finding a liquid source of nutrients (usually sodium or amino acids) and drinking it up. Butterflies are well known for it and it usually happens on soil but some are more resourceful and will even be attracted to an animal's sweat or tears.