Eastern bluebirds can live for 6 to 10 years. The record lifespan for a bluebird was 10 years and five months. However, a majority of bluebirds die within their first year of life. Starvation and freezing can threaten young bluebirds, but most threats come from other animals, including humans. Natural predators of eggs and nestlings can include eastern chipmunks, flying squirrels, American black bears, fire ants, and raccoons. Bluebirds of all ages (including adults) are threatened by rat snakes, racers, and American kestrels. Introduced species such as European starlings, house sparrows and domestic cats pose a major threat to bluebird nests, as well, with the cat being a serious predator of adult bluebirds and the other birds being competitors for nesting sites. Non-nesting adults face predation with all native species of falcons, owls, and most varieties of hawks (particularly in the Accipiter genus). When approached by a predator, males make a song-like warning cry. If a male is not present, a female will begin to sing, hoping to attract a protective male back to the territory. Both males and females also flick their wings and warble when predators are nearby, but losses are often heavy when a persistent predator finds their nest.
Copyright © 2016-2018 Animalia Life | All rights reserved