I Will Never Forget You by Tatsuya Miyanishi

A baby spinosaurus was looking for red berries near the ocean.  When a tyrannosaurus sees him, he looks like a pleasant little snack.  As he gets ready to eat him, there is an earthquake and they find themselves at sea...

Museyon and Net Galley let me read this book for review (thank you).  It will be published August 1st.

At the moment, the tyrannosaurus has lost his appetite and sets the spinosaurus down.  He's amazed at how many compliments the little gives him.  No one had done that before.  He finds out that spinosaurus' family is sick and he needs the berries to make them feel better. 

Just then, they get close enough to the spit of land that the tyrannosaurus grabs his friend and leaps over to it.  But there are no berries left, they were all on the tree on the newly made island.  The tyrannosaurus leaps back and tears the tree down.  Then he leaps again, but he doesn't make it.  He pushes the tree up on the land and tells the little one not to worry about him.  He sinks beneath the waves.

The little one was his very first friend and he wanted to help him.  He did.  The spinosaurus won't forget him.