The Juniper Titmouse was split from the Oak Titmouse (B. inornatus) of the Pacific Coast (previously known as the Plain Titmouse) after completion of the TBBA fieldwork. Rather than being considered as members of the same genus as chickadees, the two groups are now considered only distantly related within the family Paridae.
Much of the data gathered on “Plain Titmouse” was obtained in California on the Oak Titmouse and extrapolated to Juniper Titmouse. While both species consume a variety of insects (particularly in summer) and seeds, one major difference is the consumption of pinyon nuts by Juniper Titmouse while its relative relies on acorns which are stored and retrieved when other foods are in short supply. Juniper Titmice are presumed to store pinyon nuts, but more study is needed (Cicero 2000).
DISTRIBUTION. During the 1987-1992 TBBA field work atlasers found 3 possible and 2 probable breeding records near the Guadalupe Mountains of Trans-Pecos Texas. Nesting was first discovered here in 1973, providing the first breeding record for this state. Reports of this species from other parts of west Texas are probably actually young Black-crested Titmice (B. atricristatus) which acquires its fully black crest as late as its second year after hatching, progressing through gray to dull brown tipped with gray (Oberholser 1974). The species has been reported from the Davis Mountains but breeding has not been documented there (Lockwood and Freeman 2004).
Outside Texas Juniper Titmice are resident in the intermountain western United States from southern Oregon and Idaho to southern Arizona and New Mexico (Cicero 2000).
SEASONAL OCCURRENCE. Juniper Titmouse is a year-round resident in the foothills of the Guadalupe Mountains (Oberholser 1974, Lockwood and Freeman 2004). In Arizona almost all Juniper Titmouse breeding activity occurs from April 20 to July 20 (LaRue (2005).
BREEDING HABITAT. In Arizona where nesting habitat has been quantified, 61% of nests were found in pinyon-juniper woodland and nearly 10% were in evergreen oak mixed with pinyon-juniper and nearly 10% in Great Basin grassland (LaRue 2005). In Colorado over 9% of nests were found in pinyon-juniper woodland (Levad 1998). This titmouse uses natural cavities, woodpecker holes or nest boxes in preference to excavating its own cavity, although the female may enlarge a hole in soft or rotten wood. The cavity is lined with hair, grass, shredded bark, moss and rootlets (Cicero 2000).
The female usually lays 6-7 (range 3-9) white or very lightly marked eggs which she incubates for 14-16 days while the male feeds her. Only one brood is raised per season. Brood parasitism has not been reported (Cicero 2000).
STATUS. Lockwood and Freeman (2004) describe Juniper Titmouse as locally common in the foothills of the Guadalupe Mountains. The North American Breeding Bird Survey observers found this species on 1 route in Texas at a level of <1 detection per year, far too little data for a trend estimate. The 104 routes on which this titmouse was detected in the United States produced a 95% confidence interval (There is a 95% chance that the actual population trend will be between these two numbers). of -4.6 to +6.0% population change per year for the period 1966-2004 (Sauer et al. 2005). Barring a catastrophic habitat change, such as a major fire, this apparently isolated population in the Guadalupe Mountains should continue to exist.
Text by Robert C. Tweit (2006)
Cicero C. 2000. Juniper Titmouse (Baeolophus ridgwayi). In The birds of North America, No. 4851 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
LaRue, C. 2005. Juniper Titmouse (Baeolophus ridgwayi). In Arizona breeding bird atlas.pp. 388-389 (T. E. Corman and C. Wise-Gervais, eds.), University of New Mexico Press, Albuquerque.
Levad, R. 1998. Juniper Titmouse (Baeolophus ridgwayi). In Colorado breeding bird atlas, pp. 352-353 (H. E. Kingery, ed.). Colorado Bird Atlas Partnership, Denver.
Lockwood, M. W. and B. Freeman. 2004. The TOS handbook of Texas birds. Texas A&M University Press, College Station.
Oberholser, H. C. 1974. The bird life of Texas. Vol. 2. University of Texas Press, Austin.
Sauer, J. R., J. E. Hines, and J. Fallon. 2005. The North American Breeding Bird Survey, results and analysis 1966-2004. Version 2005.1. USGS Patuxent Wildlife Research Center, Laurel MD (Web site, http://www.mbr-pwrc.usgs.gov/bbs).