The Alameda Whipsnake (Masticophis lateralis), aka Striped Racer, is a colubrid snake of the California coast and foothills. It is 90–120 cm long, slender, with two yellowish stripes along its back, set against a dark brown or black back. It is fast-moving, diurnal, and an active forager. It is nonvenomous, but likely to strike if captured.
The Alameda whipsnake is known to utilize a wide range of habitat types including open desert, oak woodland, pine forest, chaparral, and associated open landscapes (Ortenburger 1928, Stebbins 2003). This species is represented by two subspecies: the chaparral whipsnake (M. l. lateralis) and the Alameda whipsnake (M. l. euryxanthus) (Stebbins 2003). The ranges of these subspecies are contiguous in the area of southern Alameda County, northern Santa Clara County, and western San Joaquin County, CA (Jennings 1983). The chaparral whipsnake has been reported to use woodlands, grasslands, scrublands, and riparian habitats (Ortenburger 1928, Swaim 1994, Alvarez, pers. obs.), and the Alameda whipsnake has commonly been reported as having a more specific association with chaparral and scrub plant communities as the habitat where it is most commonly found (Swaim and McGinnis 1992, Swaim 1994, USFWS 2002).
Whipsnakes are known to eat a variety of live animals including insects, lizards, snakes, birds, and small mammals (Stebbins 2003, Swaim 1994). They show a strong preference for lizards, which are captured by a grasp of the mouth (Swaim 1994). Whipsnakes grab their prey and swallow it alive. This species commonly moves over and through brush and trees in order to avoid predation and to capture prey. Swaim (1994) also observed the Alameda whipsnake moving into the top of scrub plants after emerging from nightly retreats to gain access to direct sunlight before the sunlight reached ground level.
As with many species and subspecies, taxonomic reclassification is an ongoing process, and differing sources often disagree. The genus Masticophis may soon be absorbed by the closely related genus Coluber, which contains the Racer (Coluber constricter).
The species is broken into two subspecies:
- Masticophis lateralis lateralis, or Chaparral Whipsnake
The Chaparral whipsnake is a common subspecies in California and northern Baja California, Mexico. The subspecies is often associated with broken (variable) habitat types that range from northwestern to extreme southern California and further south into Mexico.
- Masticophis lateralis euryxanthus, or Alameda Whipsnake
The Alameda whipsnake subspecies was first collected by Archie Mossman and later described by Riemer in 1954. The subspecies is considered threatened in the State of California. Its range is relatively small, and much of the subspecies' habitat is threatened by development. Researchers have conducted studies to better understand the use of different habitats by the Alameda whipsnake (Swaim 1994, Alvarez 2006, Alvarez et al. 2005).
- Masticophis lateralis USGS Western Ecological Research Center
- Alvarez, J. A. 2006. Masticophis lateralis euryxanthus (Alameda Whipsnake). habitat. Herpetological Review 37:233.
- Alvarez, J. A. 2005. A compilation of observations of Alameda Whipsnake outside of typical habitat. Transactions of the Western Section of the Wildlife Society 41:21-25.
- Jennings, M. R. 1983. Masticophis lateralis (Hallowel), Striped racer. Catalogue of American Amphibians and Reptiles. Society for the Study of Amphibians and Reptiles.
- Ortenburger, A. I. 1923. Whipsnakes and racers. Plimpton Press, Norwood, Massachusetts, USA.
- Riemer, W. J. 1954. A new subspecies of the snake Masticophis lateralis. Copeia 1954:45-48.
- Stebbins, R. C. 2003. A field guide to western amphibians and reptiles. Houghton Mifflin Company, Boston, Massachusetts, USA.
- Swaim, K. E., and S. M. McGinnis. 1992. Habitat associations of the Alameda whipsnake. Transactions of the Western Section of The Wildlife Society 28:107-111.
- Swaim, K.E., 1994. Aspects of the Ecology of the Alameda Whipsnake (Masticophis lateralis euryxanthus. Upublished Master's Thesis, California State University, Hayward. 140 pp.
- United States Fish and Wildlife Service. 2002. Draft recovery plan for chaparral and scrub community species east of San Francisco Bay, California, Portland, Oregon xvi + 306 pp.
- Masticophis lateralis lateralis - California Striped Racer californiaherps.com
- Masticophis lateralis euryxanthus - Alameda Striped Racer (Alameda Whipsnake) californiaherps.com
- USFWS Species Account United State Fish and Wildlife Service
- The Nature Conservancynl:Masticophis lateralis