Rattlesnakes: Fact and Fiction
By Ilene Smith, Friends and Neighbors of the Deschutes Canyon Area
By Ilene Smith, Friends and Neighbors of the Deschutes Canyon Area
Western Rattlesnake (Crotalus oreganus) | Photo credit Brad Shaffer (UCLA)
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Juvenile Northern Pacific rattlesnake in Deschutes canyon | Ilene Smith
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There are thirty-two species of rattlesnakes in the US. Although rattlesnakes are commonly seen in the Oregon High Desert, only one species of rattlesnake, the Western rattlesnake (Crotalus oreganus), is actually found here. Adding to the confusion, there are two subspecies of Western Rattlers, the brown to greenish brown Northern Pacific (Crotalus oreganus oreganus) and the Great Basin (Crotalus oreganus lutosus). The Northern Pacific rattlesnake is indigenous to western, central and northeastern Oregon. The Great Basin rattlesnake, covered in small tan oval blotches, is mostly found in desert areas of southeastern Oregon. Both subspecies blend in very well to their respective geographic areas.
Coexisting with these venomous reptiles takes some situational awareness when hiking, gardening and doing other outdoor activities. Just being aware, especially in the spring and fall, is the most important step to prevent a snake bite (envenomation). Spring is when rattlesnakes are emerging from their winter dens, and fall is the birthing season. If you do encounter a rattlesnake, just back up quietly and allow the snake to make an exit away from you.
The rattlesnake, one of the most feared reptiles, is also largely misunderstood. A common misconception is that a rattlesnake will chase or follow you. This is a myth. Rattlesnakes will attempt to retreat or escape, if possible, rather than strike a human. Rattlesnakes do not want to waste energy or venom on a non-food source (e.g., a human). They are more inclined to save their valuable venom for a food source. In the rare situation where a person is bitten, they have a 25% chance of a “dry strike” which means the rattlesnake did not inject any venom.
Another common myth is that juvenile rattlesnakes can’t control their venom quantity and therefore are more dangerous than adult rattlesnakes. Actually, juvenile rattlesnakes have the ability to control their venom load at birth. This has been proven through many well documented studies. Generally, the larger the rattlesnake, the more severe the envenomation will be.
What to Do if Bitten by a Rattlesnake (tips by one of the leading toxicologists in the US*)
• Get away from the snake. No need to hurt the snake or try to capture it for subsequent identification; the antivenom works for all rattlesnakes found in the US.
• Remove constrictive clothing and jewelry.
• Keep the affected extremity at or above heart level.
• Get to an appropriate medical facility as soon as possible to receive antivenom treatment.
• DO NOT cut or suck the wound!
• DO NOT apply a tourniquet!
• DO NOT apply heat!
• DO NOT apply ice for more than 5 minutes (reapply only after ten minutes)!
• DO NOT use any suction device on the wound!
Should You Get Your Dog Vaccinated?
The rattlesnake vaccine for canines is controversial. Recent studies suggest that they do not “buy time” to get to the vet. A study of 272 cases of rattlesnake envenomations in dogs found the vaccine did not prove effective. (See: Rattlesnake Vaccine Study)
In fact, some data suggests there may be an increased risk of anaphylaxis in dogs that are bitten by a rattlesnake following vaccination. (See: Anaphylaxis in Vaccinated Dogs)
Finally, the vaccine is only conditionally licensed by the USDA. This means the manufacturer has failed to demonstrate efficacy and potency, and as a result, the USDA has not granted the drug full approval.
Regardless of vaccination status, any dog that has been bitten by a rattlesnake, should immediately be evaluated at one of the two Central Oregon emergency pet clinics that carry antivenom: Bend Animal Emergency clinic 541-385-9110 or Veterinary Referral Center of Central Oregon 541-210-9200.
*Spencer Greene, MD, MS, FACEP, FACMT, FAACT, FAAEM is a board-certified medical toxicologist and emergency physician. He is a Clinical Professor at the University of Houston College of Medicine and director of toxicology at HCA Kingwood in Texas. Dr. Greene is a recognized expert in the management of snake envenomation in the US. He has treated more than 1,000 snakebites at the bedside and has authored more than 50 scholarly articles and book chapters. He has also served as the course director for the Houston Venom Conference since 2013.
Coexisting with these venomous reptiles takes some situational awareness when hiking, gardening and doing other outdoor activities. Just being aware, especially in the spring and fall, is the most important step to prevent a snake bite (envenomation). Spring is when rattlesnakes are emerging from their winter dens, and fall is the birthing season. If you do encounter a rattlesnake, just back up quietly and allow the snake to make an exit away from you.
The rattlesnake, one of the most feared reptiles, is also largely misunderstood. A common misconception is that a rattlesnake will chase or follow you. This is a myth. Rattlesnakes will attempt to retreat or escape, if possible, rather than strike a human. Rattlesnakes do not want to waste energy or venom on a non-food source (e.g., a human). They are more inclined to save their valuable venom for a food source. In the rare situation where a person is bitten, they have a 25% chance of a “dry strike” which means the rattlesnake did not inject any venom.
Another common myth is that juvenile rattlesnakes can’t control their venom quantity and therefore are more dangerous than adult rattlesnakes. Actually, juvenile rattlesnakes have the ability to control their venom load at birth. This has been proven through many well documented studies. Generally, the larger the rattlesnake, the more severe the envenomation will be.
What to Do if Bitten by a Rattlesnake (tips by one of the leading toxicologists in the US*)
• Get away from the snake. No need to hurt the snake or try to capture it for subsequent identification; the antivenom works for all rattlesnakes found in the US.
• Remove constrictive clothing and jewelry.
• Keep the affected extremity at or above heart level.
• Get to an appropriate medical facility as soon as possible to receive antivenom treatment.
• DO NOT cut or suck the wound!
• DO NOT apply a tourniquet!
• DO NOT apply heat!
• DO NOT apply ice for more than 5 minutes (reapply only after ten minutes)!
• DO NOT use any suction device on the wound!
Should You Get Your Dog Vaccinated?
The rattlesnake vaccine for canines is controversial. Recent studies suggest that they do not “buy time” to get to the vet. A study of 272 cases of rattlesnake envenomations in dogs found the vaccine did not prove effective. (See: Rattlesnake Vaccine Study)
In fact, some data suggests there may be an increased risk of anaphylaxis in dogs that are bitten by a rattlesnake following vaccination. (See: Anaphylaxis in Vaccinated Dogs)
Finally, the vaccine is only conditionally licensed by the USDA. This means the manufacturer has failed to demonstrate efficacy and potency, and as a result, the USDA has not granted the drug full approval.
Regardless of vaccination status, any dog that has been bitten by a rattlesnake, should immediately be evaluated at one of the two Central Oregon emergency pet clinics that carry antivenom: Bend Animal Emergency clinic 541-385-9110 or Veterinary Referral Center of Central Oregon 541-210-9200.
*Spencer Greene, MD, MS, FACEP, FACMT, FAACT, FAAEM is a board-certified medical toxicologist and emergency physician. He is a Clinical Professor at the University of Houston College of Medicine and director of toxicology at HCA Kingwood in Texas. Dr. Greene is a recognized expert in the management of snake envenomation in the US. He has treated more than 1,000 snakebites at the bedside and has authored more than 50 scholarly articles and book chapters. He has also served as the course director for the Houston Venom Conference since 2013.
