Ruby-throated hummingbirds are solitary. Adults of this species typically only come into contact for the purpose of mating, and both males and females of any age aggressively defend feeding locations within their territory. The aggressiveness becomes most pronounced in late summer to early fall as they fatten up for migration. This is important because, as part of their migration, they must fly across the Gulf of Mexico - a feat which long confounded scientists, as a 500 mile, non-stop flight over water would seemingly require a caloric energy that far exceeds an adult hummingbird's body weight of 3 grams. However, researchers discovered the tiny birds can nearly double their body mass in preparation for their Gulf crossing. The additional mass, stored as fat, provides enough energy for the birds to achieve this amazing flight.
Typically found in deciduous and pine forests and forest edges, orchards, and gardens.