There are actually five - the Mohave, Speckled and Western rattlesnakes - along with the Western Diamondback and Sidewinder.
The distinctive rattle usually gives them away.
"Watch where you're stepping. Watch where you're putting your hands. Watch where you're putting your seat, and that way you can take some steps to prevent an unpleasant experience," Nielsen said.
A bite can be fatal - especially for pets.
"Our associate - her dog was envenomated a year or so ago, so it does happen," said Dr. Terry Muratore, a veterinarian at Legacy Animal Hospital. "They're out there, and the more you're in the desert, you're going to run across them."
A $35 vaccine is available for dogs, which will buy them some precious time. But whether it is man or man's best friend, get to the hospital.
"[The vaccine's] goal is to increase survivability," said Dr. Muratore. "It is not a 100 percent preventative vaccine."
If you do find yourself bitten by a snake or discover one in your yard, the Department of Wildlife suggests you do not try to capture the reptile.
"If you can take a picture, that'll help the medical people determine what they're trying to treat for on a bite," Nielsen said.
If a venomous reptile is seen in an area where it poses a direct threat to human safety, call the Nevada Department of Wildlife's urban wildlife hotline at 702-486-5127.
Copyright 2013 KVVU (KVVU Broadcasting Corporation). All rights reserved.
Monday, July 28 2014 1:54 AM EDT2014-07-28 05:54:28 GMT
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