Spinosaurus are excellent fishermen. They are like and all Terran vehicle. They can cover alot of open ground and a good bit of water. Not recommended for deep ocean exploits as jelly fish wil sting and stun them , they'll drown in the time it takes to wake up. They're good at clearing a path for a base and can carry alot like a T-Rex. Good at harvesting prime regular and fish meat and trophies for the obelisk.
To be strictly honest the spinosaur is one of the best mounts in game if you are even wble to obtain one be sure to make it a high level one they are very squishy at first so go around killing small dinos before attacking big prey
When in water, the spino can move without using stamina, this means that in a fight, if you run into a deep water source, you don't need to worry about stamina if you need to retreat. Has an oxygen bar so you can't dive forever sadly, very fast in water though.