Could you please upload the save game? I can't reproduce it in 3.0.6.

Will do - svg uploaded, MoWin.svg.zip

There is an eel to the right. It attacks if I step next to it, but fails to chase me.

Exploring more in the cave, I found several other immobile animals, plus one mobile turtle.
Sharks / eels seem to be locked in place, turtles move, perhaps?

The monster memory for shark does not include "They ignore water.", where the turtle's description does.

Thanks! Yes, only sharks and eels were not moving. Fixed!