Answer:
Here.
Explanation:
Dinosaurs, despite living thousands or millions of years ago, behaved like modern day animals (instinct wise).
One possibility is that the land/sea dinosaur could have migrated or moved away from their suitable living spaces in hopes of finding food, space, shelter, water ect. The Bering Straight is a perfect example of 2 land masses joining together and acting as a bridge for animals/dinosaurs to cross.
Another is the ocean itself. Over the course of decades, fossils in the ocean could have easily drifted over from one land mass to another, and got stuck in it's resting place whenever the sea level drops.
