It happens. The bird was just looking for an easy meal to survive. The same reason I don't plant things in the yard wildlife would destroy. That happy median thing. I learned these things when I was landscaping new home yards. You install new plants and the wildlife come in over night and destroy all your work......Brother-in-law had a beautiful backyard koi pond years ago. It was so elaborate it was on some Atlanta pond tour for awhile. Stocked with fish in the $200 and up range.
His pride and joy. He would drink his morning coffee gazing upon it’s serene beauty.
One morning, he looks out, there’s a blue heron swallowing fish. Took a few days, but that bird cleaned out over a thousand dollars worth of stock.