The snake in the photo is a green whip snake (Hierophis Viridiflavus). It's one of the biggest snakes to be found in Europe (the species is present in Andorra, Croatia, France, Greece, Italy, Malta, Slovenia, Spain and Switzerland), and it can grow to a length of almost 2 meters. The species is normally very shy; in my experience it flees with enormous speed as soon as it senses or sees a human approaching - unless, that is, it thinks the moment for fleeing has already passed.
In those latter instances, it's very aggressive: it hisses loudly and gets into an upright position like a cobra, and if that doesn't help it will bite you and sometimes not let go (but to be clear, although a bite may be very painful and people with a phobia of snakes might die of fear, this snake is completely harmless ;-)
The German name for the snake alludes to its short-tempered character: it's called "Zorn-Natter", which means as much as "anger-snake" (but to be precise, "Natter" is the German word for snakes in the family of the Colubridae, not snakes in general).
Now this snake DID see me approach (probably long before I myself saw the snake), and judging from the look you can see in the photo above I'd say the fella wasn't exactly happy to see me - still, he didn't flee. It was early September, and I was looking for western green lizards (Lacerta bilineata) in the fly honeysuckle shrub right outside my garden in Ticino (Switzerland), when I suddenly realized a big branch stretching over the leaves of the shrub wasn't a branch at all.
Because the snake didn't flee I naturally believed it hadn't seen me, and I assumed its head was on the far end (both ends of the snake's body were hidden in the foliage), so I tried to find an angle where I could see the head in the hope of a usable photo.
No such luck: because it was the wrong end. Now the other - the near - end of the snake's body was indeed pretty near and only maybe 1.5 meters from where I stood, but my elevated point of view prevented me from seeing it, because it was hidden under the leaves (as you can see in the photo above).
When I slowly went down to my knees to take a peek, I looked right into a pair of eyes that fixated me with the not very friendly stare you see in the photos.
But why didn't the snake flee? This was strange (though I was grateful since it's not easy to get a good close-up shot of an animal that is normally so shy).
And then I saw the reason: only 80 centimeters away from the snake there was a huge male western green lizard, basking in the sun. Now it all became clear: I had obviously interrupted the "biacco" (which is the snake's Italian name) just as it was getting ready to have a juicy lizard lunch. Much as my presence caused the snake discomfort and certainly fear, it just wasn't ready to let go of such a whopper of a meal. The lizard was blissfully unaware of either me or its impending doom, and dozing with half-closed eyes.
Thus I found myself faced with a terrible dilemma. You see, western green lizards are my favorite animals, and although I adore snakes too, the tiny local western green population - already under permanent siege by the many cats in the village and always on the verge of perishing - has grown close to my heart. After observing these lizards for so long, I know most individuals by their color patterns, and the loss of any of them really gets to me. But unlike with the cats (which is a human problem that the cats - whom I love dearly as pets - aren't to blame for), this snake was a natural enemy, and it also had to eat, so I knew the right thing to do was to let nature run its course.
But knowing what the right thing to do is, and actually DOING the right thing, are decidedly not the same thing. To my shame, I decided to interfere (I honestly, REALLY am not proud of that, and I'm not kidding, but it is what it is). Once that decision was made, I quickly acted. I didn't want to chase the snake away because that seemed mean (and the fella hadn't done anything wrong), so rather than that I hoped I could catch the lizard's attention. What I actually did (and I promise that is the honest-to-God truth): I made a wave-like movement with my arm and hand. This was - obvisously - the sign for "SNAAAKE!!!" that I was sure would transcend the human-lizard communication barrier - and I'm sure it WOULD have, had Mr. Lizard not been happily dozing with its eyes now fully closed.
So I whispered: "Duuuude, there's a huuuuge snake right next to you!" Naturally, I said this in Italian (these lizards have never been outside our village, so I knew they didn't speak English ;-) . No reaction. So in a final desperate attempt I shook the branch the lizard sat on, and now it dazedly openend its eyes. It took the target of my clumsy rescue attempts maybe a second to realize a two-legged, giant monster was shaking its residence, but then it quickly dove into the foliage for cover - but not alone: the snake was right behind it! Western whip snakes are extremely agile hunters, so through my idiotic action I might have doomed my green friend (who had no idea there even was a snake lurking when I caused him to move) after all.
Truth is, I don't know what happened. Predator and prey disappeared at the same time, and then it was all quiet; I didn't hear the slightest noise that would have hinted at a struggle. When I came back to the shrub an hour or so later I spotted a male Lacerta bilineata that I'm pretty sure was the one I had tried to save. It didn't move when I approached and was either paralyzed with fear (or shock after a narrow escape), or it just thought I hadn't seen it and relied completely on its camouflage. Either way, this fella allowed me to make the best close-up and even macro shots I was ever able to make of the species (you can find those here in case you're interested).
Who knows, I keep telling myself the little fella decided to pose like that out of gratitude... ;-)