AudioDateDownLeftRightUpCloseReportGallerySettingsGiftLanguageGridListMapMenuPhotoPlayPlusSearchStarUserIconVideo

Red Crossbill

Loxia curvirostra

Order:
Passeriformes
Family:
Fringillidae
Sections
  • Authors: Adkisson, Curtis S.
  • Published: Jan 1, 1996
Listen

Free Introduction Article Access

The Introduction Article is just the first of 11 articles in each species account that provide life history information for the species. The remaining articles provide detailed information regarding distribution, migration, habitat, diet, sounds, behavior, breeding, current population status and conservation. Each species account also includes a multimedia section that displays the latest photos, audio selections and videos from Macaulay Library’s extensive galleries. Written and continually updated by acknowledged experts on each species, Birds of North America accounts include a comprehensive bibliography of published research on the species.

A subscription is needed to access the remaining account articles and multimedia content. Rates start at $5 USD for 30 days of complete access.

Subscribe Now

Already a subscriber? Sign In
Enlarge
Figure 1. Distribution of the Red Crossbill in North America.

This species also breeds in Europe, Asia, and northern Africa. In North America, Red Crossbills breed occasionally outside the mapped range. During nonbreeding periods, this species disperses irregularly south of the distribution shown.

Enlarge
Adult male Red Crossbill head detail, Grand Forks, BC, 13 March.

Crossbills are easily distinguished from all other North American birds by their crossed elongated bill tips. These are used to pry open cones from which they extract the seed. The following is a link to this photographer's website: http://www.flickr.com/photos/mikewiz/., Mar 14, 2013; photographer Mike Wisnicki

© Cornell Lab of Ornithology
Enlarge
Adult male Red Crossbill, San Mateo Co., CA, 3 May.

Typical male plumage. Bill size and depth varies among the different types of Red Crossbills. Bill size generally correlates with the kind of seeds these types prefer; larger billed birds can open stronger cones (e.g., pine), whereas smaller billed birds prefer softer cones (e.g., fir). The following is a link to this photographer's website: http://www.flickr.com/photos/ganesh_j/., May 04, 2013; photographer Ganesh Jayaraman

© Cornell Lab of Ornithology
Enlarge
Adult female Red Crossbill, San Mateo Co., CA, 3 May.

Female Red Crossbills have yellowish tones, but typically have plain grayish throats. Males often have red or yellow throats. The following is a link to this photographer's website: http://www.flickr.com/photos/ganesh_j/., May 04, 2013; photographer Ganesh Jayaraman

© Cornell Lab of Ornithology

Red Crossbills inhabit southern taiga forests from Alaska to Newfoundland, and montane coniferous forests south to Georgia in the Appalachians, Arizona, New Mexico, northern Mexico, and the Sierra Nevada of California. Wandering birds can reach the southern states, where breeding has occurred. The species also occurs in the pine forests of Central America.

The Red Crossbill shows considerable morphological and vocal variation, and classification of the species into races has been as diverse as the many authors involved. Recent progress in the classification of this diversity is the identification of eight discrete types of Flight Calls north of the Mexican border, calls that may play a major role in maintaining reproductive isolation among the groups. These call types may represent discrete species; they are, at least, nomadic populations that are usually reproductively isolated from all other crossbills.

The nomadic movements characteristic of most of these forms are driven by the variable nature of cone production over most of North America. Individual Red Crossbills of various call types may be found far from their usual haunts, sometimes feeding on atypical food sources.

Morphological variation in bill and body size appears to be part of a suite of adaptations for different species and sizes of cones in most forms of this crossbill.

Red Crossbills breed mainly when a group finds an adequate mature cone crop of the appropriate type. In some places more than two call types may breed simultaneously, with little interbreeding, and they may breed repeatedly until food is depleted below a level of profitable foraging. Even though crossbills are often said to breed in all months of the year, a recent study of one call type shows that breeding ceases, even in the presence of a bumper crop, when autumn day length becomes shorter than about 12 hours. Then, after the annual molt, breeding can resume in late December or January at day lengths of 10.5 hours.

Recommended Citation

Adkisson, Curtis S.. (1996). Red Crossbill (Loxia curvirostra), The Birds of North America (P. G. Rodewald, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America: https://birdsna.org/Species-Account/bna/species/redcro

DOI: 10.2173/bna.256