https://www.independent.co.uk/news/science/scientists-dolphins-lsd-communitcate-with-them-experiment-talk-john-lilly-margaret-howe-lovatt-a7787556.html that's just from a quick Google not sure if good, I learned about it years ago on TIL or somewhere

Edit: think this is probably better had more of the lurid details lol theguardian.com/environment/2014/jun/08/the-dolphin-who-loved-me