B.R. Moon 1987 Species Account Sidewinder (Crotalus cerastes) 10 April Kelbaker Road 3.5 miles north of highway 66 (National Trails Highway), San Bernardino county, CA. We found a large adult sidewinder crossing the pavement in early evening in sandy, low shrubby habitat. It rattled and sidewound across the road as we walked up to it after passing it in the car. 1840 PST. 3/4 full moon out at dusk.