Contributors to this thread:
Distance downwind can a deer smell?
I have often wondered how far, in yards, it takes for your scent to disapear? My guess would be about 100 yards but I am open to hear other opinions.
Nope. I train and run Search & Rescue dogs. I've seen dogs hit from over 200 yards away. Scent dispersion has a lot of variables, wind speed and consistency, air temperature and terrain.
Here is a link to a PDF that may be helpful. http://www.uspcak9.com/training/scent.pdf
Here are few good books that cover training and scent.
Scent and the Scenting Dog, by William "Bill" Syrotuck - scent theory and how to apply it in the field.
Search Dog Training, by Sandy Bryson - how to train a search dog.
Ready! The Training of the SAR Dog, by Susan Bulanda - another view on training.
Search and Rescue Dogs: Training Methods, by American Rescue Dog
Had deer across a 400 yard field bust me when the wind changed a few times. They clearly looked my way and then bolted...all of them.
I have seen them spook at over 200 yards and saw it again just last week. I was in a ground blind and had some deer circle downwind of me in a field. When they got directly downwind there was no mistaking what happened.
I saw them stand and smell and stare a Mile Away! If the wind is right....I think they can smell you.
with scentloc suit 473.5 yards, without scentloc suit 473.5 yards
I have watched bucks turn look and retreat when they hit my scent at 300 yards. I could anticipate where I thought my scent was blowing and sure enough the reaction was unmistakable.
Wind velocity, variability and humidity are a big parts of it, but I have had deer bust me from several hundred yards away. I also have been sweating my butt off and had a deer walk in right under me from down wind.
I have smelled a guy smoking from 1/2 mile so I think a deer could smell me from several miles if the wind was right.
Few years ago I was up a treestand and had to take a leak. 15 minutes later a doe and 2 fawns crossed the picked corn field about 150 to 175 yards away. As soon as they crossed my down wind, about 15 mph, all 3 noses went up in the air and they turned my direction. I thought at the time I was just above their olfactory "field of view" and all they smelled was the urine. They came to about 40 yards but wouldn't cross through a heavy brush line to where I might get a shot. One of the fawns started coming closer and mama grunted and stomped a bit to discourage it. All three turned and trotted away. I honestly don't think they ever smelled me, just my pee. The fawns were uneducated but I think mama suspected something not quite right and led them a different direction. she never blew or got loud about it but was obviously nervous and didn't want the little ones coming too close.
Who knows for sure but I'd guess in the right conditions they can smell things over a mile away. Don't know why not, their sense of smell is several orders of magnitude greater than ours.
herm- how did you see deer from a mile away? how do you know that there wasn't anything else closer to the deer that they were reacting to? ty- there is no way you could smell a guy smoking from 1/2 mile away!
Had a 155+ on my farm Wednesday at 200 yards with "maybe" a 5 mph wind at my back that caused him to get out of dodge. No snort-no commotion-just left in a hurry. I have seen that a bunch and at further distances. Cutting trails is another problem all together which is another area one has to be very critical of with big whitetails.
Makes a guy wonder how many big bucks do that to those who don't pay attention to the wind and say "There are no big deer" in my area:)
High Country you will be smelling a bunch in 6 days!
"with scentloc suit 473.5 yards, without scentloc suit 473.5 yards"
Now that was funny....and true!
2-oh-2...it was a BIG DEER! Flat terrain and NO obstacles......... ((*;
i know at least 200 yrds. got busted this morning by a group of does 6 mph wind slightly uphill flow, 29 feet up, guess i should have had my scentlok!
Watched a doe and fawn feeding towards my scent stream out in the middle of a harvested wheat field field. They were easily 1/2 a mile away. The first deer I saw all morning. When they hit directly downwind of me, lead doe stopped, looked my way and then busted it out of that wide open field. I never thought from that far they could pick you off. But I could clearly see the whole field. And there was nothing else there. Crazy!
ty- there is no way you could smell a guy smoking from 1/2 mile away!
Few years ago I was hunting in middle TN with some friends. When we got back to camp after the morning hunt I commented to one of my buddies that I could smell his cigarette smoke from my stand. The next day he marked the time when he lit one up and I marked the time when I smelled it. He lit his cigarette at 7:32 and at 7:35 I was smelling smoke. Our stands were 860 yards apart....we stepped it off.
I had a little buck downwind at 15 yards for 30 minutes. I had to pass gas the whole time really bad and was holding it. Finally I was sick of this little guy so I passed. Literally one thousand one and that little buck raised it's head and bolted like it had been shot by an arrow. So if you ever wonder now you know.
I've had educated groundhogs catch wind of me at 200+ yards!
hawkeye - do you believe groundhogs use scent to wind people much like deer. aways been debatable around here.
I don't know the exact distance but I concur with most comments for sure - I wouldn't be shocked if in the right climate and barometric conditions it would be 1/2 a mile or farther.. The funny thing is that landscapers and farmers can be working in plain sight and upwind of deer, and deer will just go about their business. I am a firm believer that deer can distinguish between "safe" human scent and "dangerous" human scent -especially in areas closer to developments.
Pdiddlydoe, I did the same thing a few weeks ago. Was watching upwind as that's where the deer were coming in off the fields. Didn't think downwind was an issue, so I passed some gas. Bad idea!! A doe and two fawns were feeding quietly downwind of me, oblivious to me until I broke wind! Haha! Vooshed and were gone literally seconds after! Lesson learned!
Deer (usually Whitetails) in Ag areas are used to smelling human scent and don't spook at the first human smell. To Jack Harris' point I am not sure they can tell safe and unsafe but I do think deer know where they are used to smelling humans and deviation is what alerts them.
As for western open and high country deer who are not used to smelling humans I think the sky's the limit. Course conditions play a factor in this. I don't have a lot of experience in this department but I think it's hard for us to comprehend the sensitivity of an ungulate's nose.
While 20 feet up in a tree and wearing two layers of scentlok I was busted at approximately 400 yards across a soybean field. In the woods the furthest I have seen myself get busted was closer to 200 yards again with scentlok.....I don't wear scentlok anymore.
I think scent lok and scent blocker can give you an edge (perhaps psychologically) but mainly when you are only dealing with thermals and drafts. I think a steady or swirling breeze over 5mph goes right through the carbon pores and disperses your stink just as if you are not blocking your scent at all. Also the possibility exists that its not the scent from within they smell but whatever you came in contact with prior to the hunt. Car seat? Your ass sits there and sweats on occasion - you can easily xfer that oder to the seat of your carbon suit. I try to put something scent free (if such a thing really exists) over seats when driving to stand. The reality is with conditions in the deer's favor, they will smell you no matter what if the deer is from NJ and over 1.5 years old. The old doe especially - there is no equal for her instincts and ability to bust you... The old doe snorts - she alerts that mature buck you never even see...
There are all kinds of things that would effect this. Here's the rule of thumb I use:
Deer are as scent-oriented as humans are vision-oriented (if not more so). If you can see a deer, he can smell you. That's probably not actually true in all situations, but it's a good idea to yourself that. If you see them or know they're there, factor your scent into everything you do from therem, ie. always stay down wind.
A deers nose is an incredible thing and should not be underestimated... ever.
I think Serb and Huh are right with the 400 yds. Seems I read an article not too long ago regarding some testing/observations done. Something about bucks along a fence line scent checking the timber, which was upwind, for hot does. The timber was somewhere around 400 yds away from the fence. Can't recall the whole thing but it was surmized they can scent from at least that distance given the right circumstances.