I agree that "sensible precautions" and "fear" aren't exactl'y the same thing,. but I have indeed seen (personally seen) incidences of people stepping on snakes. In my case these incidences were always either walking near the water or wading in it and stepping on water moccasins. As i said earlier, These snakes have no ear of man and are quite aggressive.
From the quick bit of interweb research I just did, on USA snake-bite fatalities and water moccasin/cottonmouth bites in particular;
"The Cottonmouth snake is a so called pit-viper and it is capable of delivering a rather painful bite. Fatalities from Cottonmouth bites are rare, and from the average of six annual fatalities from venomous snakebites in the US, Cottonmouths are seldom responsible for any deaths. These snakes are, generally speaking, not aggressive."
http://www.cottonmouthsnake.net/bites.htm
The article does state that a US army trainee in N Carolina died of cottonmouth bites in 2008.
To put this into context, in the UK in 2009, three walkers and one farmer were trampled to death by cows and although this was a particularly bad year, such deaths are not uncommon.
http://www.independent.co.uk/environment/nature/hoofed-and-dangerous-britains-killer-cows-1776775.html
Even for those of us living in parts of the world where it has been centuries since any of them presented a potential danger, the "fear" of spiders, snakes, wolves, bears, lions etc. have been deeply ingrained in the human psyche through folklore and fairy tails. However, deciding what are "sensible precautions" involves putting these fears to one side and carrying out a simple risk assessment exercise balancing seriousness of the risk (potentially death) against the likelihood of actually being bitten - which statistically seems to be somewhere between being struck by lightning and being trampled by cows in the UK - not being a member of a church which indulges in Darwinian (oh the irony!) practices like snake handling, should further mitigate the risk.
I'm not going to tell you how to behave in your own backyard and while there clearly is a risk and it would be prudent to take certain precautions, but it seems likely that for most people, first world risks to health and happiness are a greater danger than snakes etc.
Also sakes can't "hear" as we think of it. They can feel vibrations transmitted through the ground (and I imagine through the water also) but they are deaf to airborn sounds.
Whether or not snakes can "hear" airborne sounds seems to be a moot point;
http://jeb.biologists.org/content/215/2/ii.full
Whether they can "hear" you in the strictest sense is a bit irrelevant since with the array of sensors they possess, it is unlikely that you will get close to a conscious snake without it being aware of your presence. Whether the snake moves away, stays put hoping you haven't seen it or exhibits threatening/warning behaviour will depend on the species but (with the possible exception of some of the larger constrictors), you are not on its menu and it has nothing to gain from a confrontation with you.
More likey that low number was because wolves were virtually non-existant during that period. Not completely extinct, but nearly so. Now-a-days they're on the rebound and hunting them has been reinstated in some states. As yet they aren't generally considered much of a threat to humans (cattle and pet are a different story.
Coyotes however are quite prolific and impossible to truly control. They are also quite adaptable and do indeed hunt in suburban areas. So do black bears.
Maybe in decades to come, the expanding populations of wolves will make the north America wilderness areas as dangerous as the English countryside although I can't see a film about a belligerent herd of Jerseys being quite as compelling as the Revenant or the Grey!