“Baby birds have to be fed every 15 minutes.”
I have many nesting boxes for my bluebirds and watch cardinals, finches, titmouses, wrens, nuthatches, etc nesting on my property in the shrubs and trees. Often the parents leave the nests for long periods of time - even up to several hours. I also have chimney swifts nesting inside my fireplace chimney every year and most of the feeding takes place from 7 pm to 1 am in intervals of about an hour. There is a short period of feeding again in the morning and then nothing for the rest of the day. So this idea that baby birds must eat every 15 minutes is a lot of bunk. As long as they get enough nutrition over the course of the day, they will do fine.
My experience is different than yours. I’ve rehabbed young ‘uns and found I had to feed them every 15 minutes. It’s not an *idea*...it’s a fact. Ref: Bird Ambulance/Arline Thomas also Care of the Wild & Furred/Mae Hickman and Maxine Guy