The Pyrrhuloxia is a permanent resident of open desert scrub in the southwest-ern United States and northern Mexico. The closely related Northern Cardinal (Cardinalis cardinalis) overlaps most of the Pyrrhuloxia's range, although the cardinal is found in wetter habitats. The life histories of these 2 species have many similarities, and their vocalizations are difficult to distinguish.
The social behavior of the Pyrrhuloxia changes between breeding and nonbreeding seasons. In fall and winter, this species often forages in mixed flocks, hunting for seeds. In Texas and Arizona, flocks begin to break up in late February and early March, when males become aggressive, establish territories, and attract mates. A male establishes and maintains a territory by patrolling around the territory boundary, singing at prominent perches, and chasing intruders. Territorial behavior continues until the end of the breeding season in late summer. Where both Pyrrhuloxias and Northern Cardinals breed, territories of the 2 species may overlap, and no interspecific conflicts have been observed.
Young Pyrrhuloxias leave the nest well before growth is complete, and the fledgling period can be as long as a month before the young become fully independent and join feeding flocks.
The Pyrrhuloxia is uncommon to fairly common in suitable habitat throughout its range. In the United States, population densities are higher in Texas than in southern Arizona and New Mexico. Half a century ago this species was reported as common to abundant in some places. Habitat loss throughout its range has reduced the population.
The common name Pyrrhuloxia is derived from combining of the names of 2 bird genera, Pyrrhula (bullfinches) and Loxia (crossbills), which are derived, respectively, from the Greek words pyrruos, meaning “flame-colored or red,” and loxuos, meaning “crooked” ( Gruson 1972 ).
Most of our knowledge of the behavior and breeding ecology of the Pyrrhuloxia comes from the work of Patrick J. Gould ( Gould 1961 , Gould 1961 ) in Arizona and Roger R. Wilke ( Wilke 1995 ) in Texas.