It's a chill little game with a charming little seal :)
Suggestions:
- I don't think the game needs a "main menu", it could go straight into the game, with a bit of clear patch for the first 3 seconds so the player doesn't pop into an obstacle straight away
- The end menu is hard to read!
- Instead of having numbers on top of the fish, you could have different coloured fish, maybe a particle effect, to show which fish they are
- Could display the score/time in the game scene
- Adding a high score list would motivate people to play more
Overall a good start! Keep up the good work!