This is enough for them to fly over the Gulf of Mexico, although most probably take the long route around to reach their Central American wintering areas. Hummingbird physiology can be even more impressive during migration, when these tiny birds (they weigh the same as a penny) build up fat reserves – sometimes almost doubling their weight – to fuel sustained flight.

At night, when they can’t forage, hummingbirds often go into torpor: lowering their body temperature so less heat is lost to the cooler evening air. If a human scaled their diet to that of a hummingbird they’d need to consume over 150,000 calories a day – that’s roughly 600 average energy bars. Hummingbirds have extremely high metabolic rates and need to feed almost constantly to fuel their active flying lifestyles. As a result, they’re doing what they’d do in “natural” conditions and defend a reliable source of food like their lives depend on it. You might think there’s plenty of nectar to go around, but hummingbirds didn’t evolve in a world where flowers had a seemingly-infinite supply like feeders do. When more than one hummingbird has located a good nectar source there’s likely to be a turf war of some kind, as more dominant individuals repeatedly chase others away from “their” feeder. Young have usually fledged by late July, resulting in a noticeable increase in numbers at feeders and gardens. Ruby-throated Hummingbird perched, by George Grzyb.įor such a small bird, Ruby-throated Hummingbirds have a lot of attitude, and are known to chase all manner of birds much larger than they are – including raptors! But most of their ire is directed toward other hummers – or perhaps the occasional pollinating butterfly or bee – and late summer is the perfect time to observe these little aerialists in all their pugnacious glory. Arguably, the Ruby-throated Hummingbird ( Archilochus colubris) is among the most well-known birds in eastern North America, right up there with chickadees, cardinals, Bald Eagles, and Canada Geese, and it is without doubt the smallest. Fall migration is here, and while many birders focus on the warblers, thrushes, and sparrows starting to wing their way south, there’s another popular migrant species that’s probably familiar to a lot more people – often from the comfort of their living rooms.

Ruby throated hummingbird