While 18 species have been reported in the Reserve, snakes are rarely seen by visitors (many snakes are mainly nocturnal). The four species that are most likely to be seen are the southern Pacific rattlesnake, gopher snake, kingsnake, and striped racer. The latter two are relatively easy to identify: the kingsnake is black with (usually) yellowish annular bands (in some specimens the bands are replaced by longitudinal stripes); the striped racer is a slender snake, dark brown to black, with a thin, well-defined longitudinal stripe on each side (note: the striped racer resembles the two-striped garter snake except that the latter’s stripes aren’t so well defined). The coloration and pattern of the gopher snake are similar to that of the southern Pacific rattlesnake. When threatened, it mimics rattlesnake behavior by coiling, shaking its tail in the brush to make noise, and expelling air to make a hissing sound. But the gopher snake has the small head and round eye pupil typical of non-venomous snakes. Learn to recognize the rattler to avoid snakebites.
Past snake surveys in selected parts of the Reserve indicated that there were up to 18 species here. The UC San Diego survey found only 8. It is probable that at least a few more species are still in the Reserve but in such small numbers and in such restricted locations that their sightings are very rare. The species caught during the survey in order of decreasing abundance are the striped racer, San Diego gopher snake, Southern Pacific rattlesnake, Western ringneck snake, Calif. kingsnake, night snake, Western yellow-bellied racer, and the two-striped garter snake. The striped racer, also called the Calif. whipsnake, constituted half the specimens caught in the survey. But as its name suggests, it moves rapidly, so it is seen less often than several lesser abundant species. The ringneck snake is very localized and is unlikely to be seen, and the last three are here in such small numbers that they are also unlikely to be observed.
Keeping in mind that snakes are not often observed in the Reserve, the Southern Pacific rattlesnake and the gopher snake are the species most likely to be seen, followed by the Calif. kingsnake and the striped racer. Brief descriptions of these are given below.
Southern Pacific Rattlesnake: The colors vary from somewhat bright to dull, depending on the time since shedding. The main pattern consists of brown to blackish blotches separated by yellowish borders. Key features, characteristic of rattlesnakes, are a head considerably larger that the body and rattles on the tail. Lengths observed in the Reserve are usually up to about 3 feet, although this species can be longer.
Gopher Snake: The gopher snake somewhat resembles the rattlesnake in color and pattern, and it will even mimic the rattlesnake when threatened by coiling, shaking its tail in the brush, and hissing. But it is quite harmless. It differs from the rattlesnake by having a head about the size of its body, a round eye pupil, and of course no rattles. Specimens up to 4 feet and longer have been seen here.
Kingsnake: The most common form has a black body with yellow bands, but ones with brownish bodies are also found here. Sometimes the bands, which can also be white, are replaced by longitudinal stripes or even a combination of bands and stripes. The coloration and patterns are so distinctive that this snake is readily identified. Lengths up to 3 feet and more are here.
Striped Racer: This is a long, slender snake with a black to dark brown color on top and distinguished by a thin yellow to whitish longitudinal stripe on each side. The underside from the vent to the end of the tail is rose colored. Lengths up to 4 feet have been seen here. This snake, which is diurnal, normally moves very rapidly when approached, so visitors usually just see a tail disappearing into the vegetation. While on a docent walk one time, this writer encountered a striped racer by the side of the trail. The snake, which appeared healthy, stayed by the trail giving the visitors time to see it up close, with even the rose color under the tail being visible because of the way it was lying on the ground. This was a very unusual viewing of this species.
To put snake observations into perspective, this writer saw (excluding the reptile survey) only about 6 rattlesnakes and only several kingsnakes and striped racers during several hundred walks over seven years. So visitors should not be disappointed if they don’t see snakes during a visit to the Reserve. – John Carson
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