As you specifically mentioned Southern Nevada Mojave Desert, if you come across a snake and considering the worst case its a venomous snake, then its very likely to be a Rattlesnake or a Side Winder or an Adder.
The best way to avoid trouble with venomous reptiles is to be aware of your surroundings and observe some rules for your own safety. Most bites result from deliberate harassment of reptiles.
If you are sitting in a blind and may not make much movement, at least you should select a place to sit in a blind considering the potential habitats for these snakes and other species as well.
- Do not pick a blind spot very near to a Bush, Cacti or a pile of stones.
- Determine safety from a distance before placing hands or feet atop or among rocks or crevices
They are all members of the Viperidae family, the pit vipers. There is reason why they are called pit vipers, all these snakes have a pair of pits that help them get the heat signatures and even the fractions of temperature changes within a few feet distance. There is also a Jacobson's Organ, which perceives the chemical data received by flipping of their tongue every now and then. (Not exactly the smell, but chemical data is perceived as smell, that said, Snakes can't sniff, literally!). The data from these two Vomeronasal Organs together is what the snake use to estimate the distance between it and the prey.
Additional minute details of how it happens, which you can afford to skip reading as its not necessarily important in here with this answer:
When the tongue is flicked out into the air, receptors on the tongue pick up minuscule chemical particles, which are perceived as scent. When the tongue is retracted into its sheath, the tips of the tongue fit neatly into the Jacobson's organ, sending the chemical information that has been gathered through the organ and to the brain, where the information is quickly processed and analyzed so that the snake can act promptly on it.
The point is:
- If you follow safety instructions (probably issued by authority there who know the snake better than I do) and are very careful about picking the place such that your best bet is avoiding their area of interest/habitat, you should not come across one.
- Now, you checked the place, confirmed that there is no snake, you sit in a blind for hours. Does the safety followed earlier makes sure that no snakes comes there? Of course, it can't be guaranteed. But, with the kind of sensing organs they have and their typical behavior says that, they'll see you before you see them. And, they are more on the defensive side than being on the curious side of an animal.
- But, God forbid, if at all a rattlesnake comes around you, its likely that unless you are paying very close attention towards it, you won't see it since it camouflages itself so well, but you will hear it. Pay attention to the typical rattle noise, just as you hear it, take a careful look around, avoid panicked rapid movements and slowly get away from it at least a 15 feet, let it pass, do not try killing it or messing with it.
- I've never been hunting so this sitting in a blind scenario did make me think about how could you avoid them. In case if you have a companion, use the other person as a dedicated spotter who can spot snakes and other potential threats more carefully and frequently than you will, You can keep your eye peeled for the thing you are hunting, while your spotter ensures that nothing comes closer. Though the risk is there with Side Winders since they are so small and perfectly camouflaged with the land.
- Check with the local authority for details about the area of prominence, where the are spotted more frequently, their meeting seasons, etc. Avoid their mating season. During the mating season, and just before the season of hibernation, they tend to travel more distance than they usually do, and obviously are far more aggressive than they normally are. If I were you, I'd definitely avoid that season.
On a lighter note, irrelevant to this question: Its not only a snake than can cause you trouble there, spiders? Scorpions?
Have a safe one!