ABSTRACT
This chapter describes the California Chaparral and Oak Woodlands Ecoregion, which encompasses large portions of California, and extending south into Baja California, Mexico. The ecoregion contains black-tailed and mule deer (i.e., deer) subspecies with the former restricted to northwestern California. Most migration occurs in populations associated with the Sierra Nevada and San Gorgonio Mountain ranges in California. The climate is Mediterranean with generally mild temperatures but with seasonally pronounced cool, wet winters, and hot, dry summers with the exception of Arizona chaparral. Plant communities across the ecoregion vary with temperature, rainfall, and soil depth with the main growing season, and highest plant nutritional value for mule deer, in the early spring. Because rainfall primarily occurs during winter, summer through late autumn is the hardest part of the year for these mule deer. Deer abundance in California generally decreases from north to south except for exurban areas and riparian zones near agriculture where densities can be quite high. Limiting factors for deer in this ecoregion include loss of habitat quality from land conversion to agriculture and human infrastructure.
