I got some of the creatures blocked in, easy peasy. Specifically a turtle and an octopus. I have yet to block in the Whale.
I also consulted Noah Kentworthz on a workflow in Houdini on schools of fish involving a POP sim with a sphere to use to attract the points as well as an offset that made the geometry wiggly like fish. Thus, creating a school of fish without animating or rigging, which is a huge boon for our production I feel. After that, I just have to figure out how to keep the fish from colliding with eachother.

