Thanks for all the replies and excellent photos, it's been very interesting.
To be clear, I don't hate snakes, I just don't like them, I can admire them for what they are, beautiful creatures, with astounding abilities and hunting skills.
I have only come across a mating pair once, the female was heavily pregnant, and the male was very protective.
They made no attempt to come towards me, in fact they just wanted to hide in the long grass.
The chap I was with thought it a good idea to try and take pictures of them, and did his utmost to stop them retreating by using his landing net handle to poke in the grass for them. I left him to it, and carefully made my way back to the car.
I dread to think what the outcome might have been if I had stood on one by accident, the camouflage is first rate, and it was easily done.
The Adder is a venomous snake, I hope the following goes a little way to explaining more about it.
This species is responsible for more fatalities than any other African snake. This is due to a combination of factors, including its wide distribution, common occurrence, large size, potent venom that is produced in large amounts, long fangs that inject it deeply, their reliance on camouflage which makes these snakes reluctant to flee, their habit of basking by footpaths and sitting quietly when approached, and their willingness to bite. The venom is one of the most toxic of any viper. The LD50 values in mice vary: 0.4–2.0 mg/kg IV, 0.9–3.7 mg/kg IP, 4.4–7.7 mg/kg SC. Mallow et al. (2003) give an LD50 range of 1.0–7.75 mg/kg SC. Venom yield is typically between 100–350 mg, with a maximum of 750 mg. Brown (1973) mentions a venom yield of 180–750 mg. About 100 mg is thought to be enough to kill a healthy adult human male, with death occurring after 25 hours or more. The average specimen may have enough venom to kill 4 to 5 men. B. arietans.In humans, bites from this species can produce severe local and systemic symptoms. Based on the degree and type of local effect, bites can be divided into two symptomatic categories: those with little or no surface extravasation, and those with hemorrhages evident as ecchymosis, bleeding and swelling. In both cases there is severe pain and tenderness, but in the latter there is widespread superficial or deep necrosis. Serious bites cause limbs to become immovably flexed as a result of significant hemorrhage or coagulation in the affected muscles. Residual induration, however, is rare and usually these areas completely resolve. Other bite symptoms that may occur in humans include oedema, which may become extensive, shock, watery blood oozing from the puncture wounds, nausea and vomiting, subcutaneous bruising, blood blisters that may form rapidly, and a painful swelling of the regional lymph nodes. Swelling usually decreases after a few days, except for the area immediately around the bite site. Hypotension, together with weakness, dizziness and periods of semi- or unconsciousness is also reported. If not treated carefully, necrosis will spread, causing skin, subcutaneous tissue and muscle to separate from healthy tissue and eventually slough with serous exudate. The slough may be superficial or deep, sometimes down to the bone. Gangrene and secondary infections commonly occurs and can result in loss of digits and limbs. Despite all of this, deaths are exceptional and probably occurs in less than 10% of all untreated cases, usually in 2–4 days from complications following blood volume deficit and a disseminated intravascular coagulopathy. Most fatalities are associated with bad clinical management and neglect
Living here in Utah I've run into rattlers a couple of times. They've never been on the water though they're always up in the mountains. I live in the foothills on the U of Utah campus and one of the only "emergency alerts" we ever get is rattlesnake sightings. While I was hiking one day one of my buddies had one slither literally right between his legs as we were walking down the path. Scared me to death but the thing didn't even turn and look at us. I'd say generally they aren't anything to worry about, especially in waders.
Living both in Missouri and Montana, I've had quite a few encounters with venomous snakes while fishing. I'm not in the least afraid of them, but have a healthy respect for them, and I know for sure how to identify venomous ones. Some people I've fished with have a true snake phobia, and it precludes them from really enjoying being in the outdoors. They spend more time looking for snakes than they do fishing or looking at the scenery.
In Montana, on the West Boulder River a couple years ago, I sat down on a rock at water's edge to watch a buddy fish a run, and a good sized rattler came out from under the rock, between my feet, and into the water.
In Missouri, there is one stream that I float fish once a year, where I always see from 2 to 10 cottonmouths a day. On most Ozark streams cottonmouths are rare, but not on this one.
I had a big copperhead swimming downstream, heading straight for my canoe, on the James River in MO. I watched it come, interested because you seldom see copperheads, a terrestrial pit viper, spending a lot of time in the water. They usually just swim straight across a stream to get to the other side. This one came right up to the canoe, and I thought it was going to come in and got ready to beat it off with my paddle, but instead it swam under the front of the canoe and on downriver to a log jam about 30 yards downstream, where it got out to sun itself. I'm sure that many people would have freaked out, beat the snake off, and then swore it was coming into the canoe to attack them. Pit vipers don't attack people, but they don't really fear people all that much, and tend to not let the presence of a person deter them from going where they wish to go.
Maybe the scariest encounter I've ever had with a venomous snake was when I was a teenager in Missouri. I was squirrel hunting along a bluff on the river close to the house. The bluff had a talus slope covered with big trees, then a sheer rock face from 10-30 feet high, and then more big trees atop it. I would sneak along the top of the talus slope, where I could shoot squirrels out of the trees along the slope and also atop the bluff. I shot a squirrel which fell atop the bluff, and needed to climb the sheer cliff to get to it. There was a spot where the rock face was low enough that I could reach above my head and grab the upper edge of the rock and pull myself up. I reached up and laid my .22 atop the rock, then grabbed the edge with both hands and pulled myself up. When my head came up above the edge, there was a copperhead, coiled and ready to strike, about 10 inches in front of my nose!
I shoved myself off the rock and tumbled 10 feet down the slope. Then I picked another place to climb it where I could see where I was going. When I got to where I'd put my rifle, the snake was still there, about a foot from the rifle, but it retreated when I got close.
Having spent many summer weeks of my youth in Scout camp and possessing much more curiosity than sense at the time, I've received several bites, fortunately none of a venomous nature. Like most who have weighed in on this thread, leave them alone and they'll return the favor.
That being said, a bite from non-venomous snake (from my experience) is probably more startling than painful. Common water snakes being the exception, those little *******s can clamp down on a finger and won't let go until you fling them across the creek. Still, not much more painful than a paper cut.
We've got our fair share of copperheads and some small rattlers in Indiana but honestly I've never had too much concern about running into one, never actually have for that matter, I think the notion of them being more scared of you than you of them is pretty spot on.
growing up in georgia Ive come across my fair share of Eastern Diamondbacks (one of the most poisonous snakes in the country and the world). Those guys are push overs and typically will just go on past you or just sit there and sing while you work around them. The only snake that gives us problems is a water moccasin. They are super aggressive and known to chase you down. Ive had a few come in the boat with me while fishing on the suwannee river and that is never a good time.