I cant get an interaction for dolphins on the bouy despite them swimming around it

When you see them swimming, try clicking the dolphins themselves. This works most of the time, you should see an option "Call Over Dolphin". It doesn't always show on the first click but keep persisting, it'll show up :)

Edit: In fact, it looks like it's the swimming fish directly beneath the buoy that you click.

https://i.imgur.com/x5sW8OK.png


https://i.imgur.com/szDkubC.jpg