Most birds are omnivores, eating both vegetation and meat of some kind.
Edited to add: Birds will eat what is available so I suspect this is occurring because more meat and less vegetation is presently in their environment.
In Canada, our wild birds tend to be more carnivorous during the spring, summer, and fall when insects are plentiful. The ones that don't go south become more vegetarian during the winter as that is what is most plentiful. For birds of prey, they will usually feast on whatever is available as well, but tend to stick predominantly to a meat diet such as mice, small animals, birds, etc.
