Changes in the daily variability of high and low temperatures in certain regions may stress wild bird populations. A new study of semi-wildish Zebra Finches demonstrates this. I have a post on the research here, at 10,000 birds. Have a look!
Every pilot knows that it's easier to get a plane into the air on cold days — shorter takeoff runs — because cold air is denser than warm air. I wonder how this would affect birds. Would they need more food as the mean temperature of the air they fly in climbs?