Modern man doesn’t scavenge for food. French fries don’t need to be hunted and doughnuts won’t run away. Just look around. There’s a Krispy Kreme or a McDonald’s on every corner!
And all this food means a lot of waste. Go to any public park or look outside any restaurant and you’ll find a ton of discarded food strewn about.
Leftover junk food isn’t nutritious and the chicks of urban crows are smaller and deficient in protein and calcium, compared to crows living in rural areas. Suburban crows eating natural food grow up bigger and stronger.
Here’s the problem. Crows are opportunists and scientists suspect they’ll feed their young with whatever is easier to find and cities are hotbeds for scraps of junk.