Hummingbirds face climate-related welfare threats from phenological mismatch — when flower bloom timing shifts independently of hummingbird migration schedule.
Hummingbird welfare is existentially dependent on flower timing: arriving migrants that find no nectar sources must rapidly move on or risk starvation. The energy economics are extreme — hummingbirds maintain the highest body temperature of any bird and must eat their own body weight in nectar daily. Phenological mismatch driven by climate change creates a welfare crisis for migrants arriving into a landscape whose flowers have advanced beyond their schedule. Supplementary feeders and later-blooming native plants provide welfare insurance during the mismatch period.