The southwestern desert has a reputation for venomous critters, but which are most dangerous? I attended a lecture at the Arizona-Sonora Desert Museum given by James W. Cornett, a biologist, author, and emeritus Curator of Natural Science at the Palm Springs Desert Museum. Cornett has studied venomous animals for over 30 years and gave us a list of what he considers the thirteen most dangerous animals.
This list is subjective and includes consideration of the toxicity of the venom, the amount of venom injected, the possibility of an allergic reaction, the abundance of the animal, and the probability you could actually encounter the animal. Here is his list from the least dangerous to most dangerous:
13. Tarantulas. The venom is generally not dangerous to humans and it takes much provocation to get a tarantula to bite you.
12. Centipedes. Some of these can get over 10 inches long (but most are about 5 – to 8 inches) They deliver venom by pinching with its front legs. One death has been attributed to a centipede bite.
11. Velvet ants (actually wasps). These look fuzzy and cute but deliver a very painful bite.
10. Gila monster. These lizards are venomous but it takes some provocation to get them to bite you. (Note: that provocation can be trying to be nice and carrying one off the road so that it doesn’t get run over.)
9. Coral snakes. The coral snakes in the Southwest are generally small. More deaths occur in the East where the snakes are larger.
8. Cone-nosed bugs (aka Kissing bugs). Bites from these bugs can produce an allergic reaction and can transmit Chagas Disease, a chronic and debilitating protozoan infection. Cone-nosed bugs feed on the blood of other animals, mostly rodents.
7. Ants. Swarming ants, by their large numbers can deliver painful bites and cause allergic reactions.
6. Scorpions. Most scorpion stings in the southwest are not dangerous. However, bark scorpion venom is dangerous to humans.
5. Brown (recluse) spiders. The venom is very persistent and causes tissue damage.
3. Black Widow spiders. Drop for drop, black widow venom is the most toxic of any animal in the southwest. And now, we are seeing more Brown Widow spiders coming into the area.
2. Rattlesnakes. This venom does great tissue damage and two species, the Tiger rattlesnake and Mohave rattlesnake also have neurotoxic venom. By the way, there are 18 rattlesnake species common to Arizona.
And the most dangerous venomous animal:
1. Africanized Honey Bees. According to Cornett, bees cause more deaths than all the other animals combined.
Besides these animals, Cornett mentioned some snakes that are considered only mildly venomous, some of which are commonly kept as pets. None of these snakes have fangs, but the do have enlarged back teeth and toxic saliva. They need to chew on you for a while to work the venom in. These snakes include the ring-necked snake, black-headed snake, spotted night snake, lyre snake, hog-nosed snake, and the common garter snake.
Cornett related an incident with a hog-nosed snake. This snake was in an exhibit at the Palm Springs Desert Museum. Cornett was attempting to feed it a mouse, but since he handled the mouse, its scent got on Cornett’s hand. The snake bit him on the web between thumb and forefinger and chewed for a while before it could be detached. This mild venom caused swelling and discoloration of Cornett’s hand and arm and produced blisters for about a month. Nobody has antivenom for these snakes.
For more information on venomous animals, see:
Desert Bees and Africanized Bees
Scorpions, Vinegaroons, and Sun Spiders
Tarantula Hawks Deliver The Big Sting
Venomous Centipedes and Cyanide-Oozing Millipedes
Who’s Afraid of Tarantulas?