Florida officials are finding dead dolphins washed up on beaches. The mammals show signs or trauma, gunshot or stab wounds. They suspect part of the problems stems from people feeding wild dolphins. They warn people not to feed the animals. Good advice!
I grew up in Daytona Beach, Florida. The natives knew better than to feed seagulls.
The same scenario applies in an urban setting. Opportunists will flock to a free lunch. This upsets the local ecology.