Composition is fine and it is a very unique take on the challenge theme. DOF in this image is great. It would be a better image if you could have had some light coming from the front on the left side to better illuminate the bird, bowl and front of the holder for a more even lighting distribution.
I like the bringing of a subject into the food competition. I'd have like to have seen more of the food itself though. That said it's hard to make it apetising for a human...
This might be a recipe for bird food, so maybe it meets the challenge. Since the category is food, I think I would like to see more of the food and less of the water bowl and side of the feeder.