Mojave Green Rattlesnake
The only venomous snakes in California are the following species of Western rattlesnakes:
- The Southern Pacific Rattlesnake (Crotalus viridis helleri)*
- The Great Basin Rattlesnake (Crotalus viridis lutosus)*
- The Northern Pacific Rattlesnake (Crotalus viridis oreganus)*
- The Western Diamondback (Crotalus atrox)
- The Red Diamondback (Crotalus ruber)
- The Sidewinder (Crotalus cerastes)
- The Speckled Rattlesnake (Crotalus mitchellii)
- The Mojave Rattlesnake (Crotalus scutalatus) A.K.A The Mojave Green Rattlesnake
- native to California
While the physical appearance of each snake species is variable, there are some general characteristics specific to poisonous snakes. These include:
- Broad, triangular head with a noticeable “neck” behind the head
- Vertical pupils – Non-poisonous snakes have round pupils.
- Heat-sensing “pits” between the eye and nostril (used to help locate prey)
- And in rattlesnakes, an obvious rattle on the end of their tail!
Rattlesnakes can be found in both suburban AND rural areas. In Northern California, snakes will hibernate during cold months and are active March through September. In Southern California, they are typically active year round.
RATTLESNAKE BITES IN GENERAL
Most snake bites to dogs occur on the face or extremities when the dog encounters the snake’s natural habitat. Rattlesnake bites are generally “hemotoxic” (affecting the blood and vascular system), which means they exert their toxins by disrupting the integrity of the blood vessels. The swelling that such a bite causes is often dramatic, with up to 1/3 of the total blood circulation being lost into the tissues in a matter of hours. The toxin further disrupts the normal blood clotting mechanisms, leading to uncontrolled bleeding. This kind of blood loss can induce shock, eventually leading to death. As a whole, bites to the face are often more lethal, as the immense swelling may migrate to the neck and throat, thereby limiting a dog’s ability to breathe.
Only one of the above species is not considered venomously “hemotoxic”, and that is the Mojave rattlesnake. This species’ venom is “neurotoxic” (affecting the nervous system). Effects of this type of venom can include rapid paralysis, including paralysis of the muscles within the respiratory system which can lead to suffocation.
HOW SERIOUS IS A RATTLESNAKE BITE
The gravity of the situation involving a snake bite depends on two major factors, the species of snake and the size of the dog, and the amount of venom injected (20-25% of bites are “dry” meaning no venom has been injected, 30% are “mild” meaning they cause localized pain and swelling without effects to the entire body system, 40% are “severe”, and 5% are fatal.
SEEK VETERINARY CARE IMMEDIATELY! The quicker a bite wound is recognized, the more effective treatment will be.
Circulatory collapse is the most common cause of death relative to snake bite wounds. IV fluid therapy and monitoring of blood pressure is very important. A minimum of 24 hours of IV fluid administration can be expected in cases of snake bites.
There are numerous misconceptions about antivenin. The first is simply the name of the product. Antivenin is NOT “anti-VENOM”. It is not a single injection that provides the antidote to snake bite venom. Antivenin is a biological product consisting of antibodies made by horses in response to exposure to four common rattlesnake venoms. The antibody serum is reconstituted into an IV drip that is run into the patient over a 30-60 minute period. Antivenin is VERY expensive. A single vial can run $400 or more, and large dogs may require several vials. A newer, more purified product is being marketed that is derived from sheep. These vials can reach up to $700! Antivenin is generally helpful in the inactivation of snake venom, however, there is a very narrow window during which it must be used. After approximately 4 hours post-bite, antivenin is of minimal use.
Injections of antihistamines may also be beneficial in snake bite victims. They may be used to decrease the inflammation surrounding the bite wound itself, and may also be used to combat anaphylactic reactions from antivenin.
Other treatments may include blood transfusions as necessary in cases of life-threatening blood loss, antibiotics to control secondary infections, and pain medication.