There are eight creatures in total that you will need to encounter throughout Submerged.
All bar one of the creatures are in the water with the only land creature being one of the creatures that is stalking Miku throughout the game.
1.Dolphins are hard to miss and will most likely follow you around (annoying you)
2.Flying Fish are the little ones, you'll see these in group
3.Whale that jumps out the water (found near the compass North of the map) or on the outskirts of the city
4.Manta Ray5.Pelicans can be found sitting on top of the water
6.Human like creatures, you may need to use the telescope to capture these guys as you won't get close to them and can only see them when attempting to go for packages.
7.Whale: I've seen this swimming a lot near the "home" location on the map, pretty sure it's the most common whale
8.Whale Shark. Easily identifiable by its fin. Mostly around the outskirts of the city
Most should come up as seen when you get close but you can use the telescope if need be.
You can see which animals you are missing by looking in your journal in game.*The Human like Creatures are missable, if you don't get them throughout the Story they will not appear in Explore mode, all animals will however*