Will they increase, decrease, or stay the same

If the raccoon population decreases then that would mean that the duck population would go up because there will be less things eating them. And if the duck population goes up then the frog population would go down because their would be more ducks to eat them. The owl population might not be affected though because that doesn't effect the if there are more ducks or not, but it might make them increase because they would have more food and might not be fighting with the raccoons for food.

Explanation:

I could be wrong. Best of luck with your future questions!