- Author: Robert J Keiffer
This is the time of the year when Northern Pacific Rattlesnakes (Crotalus oreganus oreganus) are venturing back to winter den sites... and most are already there. First year youngsters, such as this one, follow the scent trail of other experienced rattlesnakes in order to locate a den site. Research (not local research) has shown that once a individual rattlesnake uses a winter den site then it will return to that same site for subsequent winter denning.
It was just yesterday that I photographed this very small snake near a known den site on the UC Hopland Research & Extension Center. Young snakes this small only have a single "button" rattle on their tails ... which is so small and not connected to other rattle segments (yet) that no sound will emit when the tail is vibrated. Hence, these small snakes are not able to give much of a warning when disturbed. Many human rattlesnake bites are due to small fellows like this one ... many times biting people's hands or fingers as they garden.
Despite the small size, they can still strike with a venomous bite. Since their venom glands are small, the amount of venom they can inject is much less than an adult snake, however, immature rattlesnakes have a much higher percentage of neurotoxins compared to hemotoxins in their venom... a trait that reverses when the snake matures. Check out the CaliforniaHerps.com website (click here) for further information.