Here is a Rudy throated fact sheet. No "pairs" hanging out or migrating together.
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How do they reproduce?
Ruby-throated hummingbirds are probably polygynous (one male mates with many females). However, mating behavior has not been studied very well in this species. It is also possible the each female mates with many males.
Males return to the breeding area in the spring and find a territory before the females arrive. When the females return, males try to attract them by performing courtship displays. When a female enters a male’s territory, the male fluffs out his red-throat feathers and begins harassing the female. He may also perform a “dive display” by diving over and over above the females head. If the female perches, the male starts flying back and forth in front of her very quickly. During this display, the male's wings can beat up to 200 times per second. If the female is receptive to the male, she may give a “mew” call and assume a solicitous posture with her tail feather cocked and her wings drooped. After a male and female copulate, they do not stay together. The male searches for another female to copulate with and the female builds the nest and raises the chicks alone. (
Robinson, et al., 1996)
Mating System
The female chooses a nest site and builds a nest. She builds the nest near the tip of a branch. Females usually chose a spot that is above an open area and shaded by leaves. The nests are made of plant material, spider webs, bud scales and pine resin. The outside of the nest is decorated with lichens.
When the nest is finished, the female lays 2 eggs. She incubates the eggs for 10 to 14 days. The chicks are helpless when they hatch, and must be kept warm by the female. The chicks leave the nest when they are 18 to 22 days old. The female keeps feeding them until they are 22 to 25 days old.
These birds probably breed the next year when they are 1 year old. Ruby-throated hummingbirds can raise up to three broods each year. (
Robinson, et al., 1996)
