Before saying anything, I'd like to point out that the images and general gist of this post were previously used for a mini-lecture at the U of M, mainly to test presentation-giving skills. Since the world has existed for long enough without a decent tutorial on mountain-viper capture, it was decided that it should go up here as well.

First of all, you may well ask, what is a mountain viper? It's a species of small viper endemic to Lebanon* and restricted to mountainous areas some 1400-1600 m up. It goes by the names
Vipera bornmuelleri and
Montivipera bornmuelleri; there is some disagreement about genus-level taxonomy but I won't go into that. As mentioned, it's endemic to a small country, and as such is endangered and poorly studied, with next to no info on venom toxicology and biochemistry, behavior, and whatnot. If you don't know what one looks like, see the picture, taken from
here.
*
And Syria too, I think, but the population there may have disappeared already.
So you want to study this animal, eh? There certainly are many good questions for research on this viper. However, as an endangered animal, you will need permission to collect it; affiliation with an institute of higher learning is preferred. And, of course, you'll need to be in Lebanon to do anything about it.

This is typical habitat for
Vipera bornmuelleri - high mountains in Faraya, and the snakes are active with snow still on the ground, which says a lot about the hardiness of "cold-blooded" animals. This is May, and it's the mating season for our vipers, so they're more active and easy to spot. Yes, we were planning on going around and seizing libidinous snakes before they could carry out their amorous intentions. We were jerks.
But before you do any snake-catching, you need...

... a place to stay! Us "warm-blooded" animals need somewhere to keep us reasonably warm. This shrink-wrapped house does the job nicely, even with no hot running water and us half-freezing to death. Besides, there's a lovely view of the waterfall in the back, what.

And, after a place to stay comes sustenance. Contrary to popular belief*, vipers don't come out in midday, but rather in the morning. By the time the sun is at its hottest, the snakes retire to their cool dens between the rocks. Ergo, you must be up bright and early to get your snakes, and there's nothing like an early breakfast to get ready for snake-wrangling.
*
Or, at least the popular belief I've been exposed to.
The sustenance in question here is
man'oucheh, which is a sort of Lebanese pizza that people eat for breakfast. It's usually a pizzaish flat bread with thyme, sesame seeds, and olive oil on top. Or cheese on top. Or both. And you can mix it up with cucumbers, olives, lettuce, tomatoes, pickles, and all sorts. Some avant-guarde vendors are making hamburger man'ouchehs - neither fish nor fowl nor genetic abomination.

But I digress. I'm here to talk about snakes, for fhtagn's sake!
The last bit of essential equipment you will need in your arsenal will be a pair of reliable snake-handling tongs, like the ones* I am holding here. They're big, they're fat, they're chunky, and they make you feel safe from a species whose toxicity has not been formally evaluated.
*
Dunno if it should stay pluralized.
However, these particular tongs proved to be way too big for the purpose of catching relatively tiny little vipers. Instead, test-tube tongs and barbecue tongs proved to do the job just as well, and they were far less unwieldy.
So you finally got a place to stay, an early breakfast, and appropriate equipment. On to the field!

This is typical mountain viper territory. In fact, one of our specimens came right from here. The snakes like to bask on limestone rocks, and dart for the nearest crevice when they sense someone approaching*. The correct approach is to walk softly** on tiptoes, and grab the snake with the tongs before it can bolt.
*
Yes, Virginia, snakes are wild animals like any other wild animal, and their primary concern is to be left alone. They are not bloodthirsty monsters out for human lives.**
And carry big tongs.
Unless this happens. Sheep and goats are one of the main reasons why mountain vipers are going the way of the dodo; they're destroying their habitat, trampling them underfoot, and making a royal mess of things. They also make a mess of things if they show up while you're collecting; in this case, your day is ruined. Any potentially capturable snakes will head for the hills, and there's nothing left to do but count darkling beetles.
The sheep are entertaining though - note that the leaders of the flock are decked out with woolen hats so the shepherd can tell them apart. Oh, and the shepherd himself is entertaining, especially if he tries to sell you his homemade snakebite remedy.

When you finally do spot a snake, chances are you'll erupt into a frenzied burst of activity as you try to grab the snake without a) allowing to escape, b) injuring it, or c) allowing it to injure itself. Mountain vipers (as opposed to lebetine and Palestine vipers) are extremely testy, and a cornered viper will hiss and thrash about impressively, sometimes breaking its own spine in the process. Even in captivity, they will start puffing up and hissing whenever I passed by (something that never happened with the larger vipers). Caution is the key word here.

Once the snake is bagged, though, things will be a lot easier. A bagged snake has no visual reference and calms down instantly. It can then be safely transferred to a suitable holding vessel, and, eventually, an aquarium. Note that the jar in the picture has two snakes (one is below the big one in an aggressive S-loop) plus a twig that somehow got in during the general confusion that follows a snake capture.
Now that you've got your snakes, you can do whatever your heart desires, and answer whatever big questions you may have had about them. You did not know about how to capture mountain vipers before. And know you know. And knowing is half the battle...