my neighbors rollers, left to free fly mostly, used to eat insects, chase mice, and eat a lot of road kill, till the female got hit by a car. i originally assumed they were eating tiny bugs off the insides of carcasses but they turned out to be eating the meat. as they were getting chick feed and laying pellets, parakeet food, wild bird seed, and corn, rice tortilla ect does that inciates that something was till missing from diet for them to be eating animal protiens, esspecially when trying to nest it seemed? id never noticed pigeons doing any of this before when worked with pigeons in non pet thing, besides bugs, but then even mostly ants ect.
