I was going to wait till tomorrow to post this- but I couldn't wait! I loves me some green hair girls! I hope you do too. It makes sense though, mermaids wouldn't want to eat their fish friends so they would eat lots of green kelp- thus turning their hair green. I did the topless thing (which I still feel guilty about) because it also seemed the most "natural" look for a mermaid. Having that blue marker run dry actually worked out this time! I like the effect.
PS. Optional story: I did her thinking and twirling her hair as an homage to my buddy/mentor, the great Disney animator Mark Henn- who animated about half of the Ariel scenes in the film. I remember going to see the first trailer for Mermaid (it was playing in the screening room for the animation tour in FLorida soon after we got there for the opening of the studio) and it was the first time we had seen it. Because Mark finished his animation on Mermaid and got onto a plane to move to Florida, it was the first time he was seeing some of his scenes in color. The scene where she overhears Eric saying he is going to marry Ursula/princess, and Ariel hides behind the pillar, breathing hard and nervously flicking her hand and then fitting with her hair came on and I was blown away! It was Mark's animation and one of the best scenes in the film. I went on and on about it and he kept watching it over and over saying he wished he had made some changes to it. He loved it and hated it at the same time. Anyway, he invented the whole nervously fitting with her hair thing. He used it again, later, with Jasmine too.