These are what I use to gather fish meat, which is useful since they, amongst other things such as otters, only eat fish meat. It’s a must have when breeding them and other fish eating dinos. Simply swim off shore, stun any megs/mantas, eat them as they sit there helplessly, rinse and repeat.
Good mount fast and can swim. Many says it is one of the best cave mounts. But for me every cave has its best mounts. It is best for swamp caves. The reason why its not good is because it needs fish meat. You don't get fish meat available in all caves. Most you encounter are raw meat givers. You can increase lost health by feeding meat or non veg to the respective dinos. I am taking a very basic perspective of cave venturing scenerio. So you have to pack a lot of fish meat before going in or something else you can do for this. Or just take a good level meat eating mount.