Understanding Thermals

[Northcountryman]

The area that I hunt has a lot of steep changes in elevation and, I’ve struggled to understand deer movements in terms of their diurnal tendencies or patterns on a consistent basis . My feeling is ,that they tend to bed on the ridges And slopes near the Creek down in a bit in elevation and tend to travel up higher to feed in the fields and around houses in the afternoon due to thermals advantageous to them . From my reading , I understand that morning thermals cause air to rise as it a heated and creates a thermal drifting upward whereas , in the late afternoon , once temps are dropping , air cools and drops , causing thermals to drift downward or, to lower elevations . Considering this , I’m thinking that deer tend to prefer traveling against the thermals in order to maximize their scent detecting abilities ; thus , they would travel down in elevation or slope in the early morning as thermals drift up towards their noses and upward or higher I. Elevation in the afternoon as thermals pull scent down to them from above .

Applying this to the area that I hunt , I’m thinking that coming in from the creek bottom at an angle and climb a bit to a mid level ridge -expecting deer to be traveling down from the top in the am-would be optimal for a morning hunt . If I come up from the top - which I could do and would actually be easier , travel wise - I’m afraid I’ll bump them noise-wise traveling with them towards the ridges above the creek . What do you think ? 
 

Thanks 

[moog5050]

Hunting ridges, I think of it this way, once thermals kick in (which is after first light), I want to be above where deer are traveling so scent is rising above them.  If you are below the deer when thermals are rising, your scent rises to them.  IE hunt high in the morning, above expected travel routes.   
 

just the opposite late afternoon as thermals start dropping.   Hunt below expected travel routes so thermals are pulling your scent away from the higher trails.   
 

Couple of things to note, there are times thermals can assist with bad predominate wind meaning you can hunt a stand that does not seem right for wind.   Also, if relying on thermals in morning, you may have a bad situation from dark until thermals actually change and start rising.   Lastly, water changes thermal effect.   My experience is that creeks tend to pull thermals towards it.   You need to check with milkweed what is actually happening if hunting a creek bottom.  
 

not sure any of that answers your question on access.   I would be more concerned with predominate wind and bumping deer than thermals on access.
 

One of the reasons that bucks travel that 1/3 leaward line from the top of a   Ridge is to scent above them from wind rolling over ridge and below them as thermals pull scent from below.   At least that is my understanding.  

Edited December 19, 2020 by moog5050

[BowmanMike]

3 hours ago, moog5050 said:

Hunting ridges, I think of it this way, once thermals kick in (which is after first light), I want to be above where deer are traveling so scent is rising above them.  If you are below the deer when thermals are rising, your scent rises to them.  IE hunt high in the morning, above expected travel routes.   
 

just the opposite late afternoon as thermals start dropping.   Hunt below expected travel routes so thermals are pulling your scent away from the higher trails.   
 

Couple of things to note, there are times thermals can assist with bad predominate wind meaning you can hunt a stand that does not seem right for wind.   Also, if relying on thermals in morning, you may have a bad situation from dark until thermals actually change and start rising.   Lastly, water changes thermal effect.   My experience is that creeks tend to pull thermals towards it.   You need to check with milkweed what is actually happening if hunting a creek bottom.  
 

not sure any of that answers your question on access.   I would be more concerned with predominate wind and bumping deer than thermals on access.
 

One of the reasons that bucks travel that 1/3 leaward line from the top of a   Ridge is to scent above them from wind rolling over ridge and below them as thermals pull scent from below.   At least that is my understanding.  

Good summary moog..Deer tend to bed high in the a.m. to take advantage of the rising thermals..A strong wind will override thermals,but when the wind stops thermals take over. Milkweed is the best way to see what really happens. Creek bottoms are very difficult to hunt because the wind tends to swirl there,especially if it is a narrow valley.

The hunting public had a great video where they were on some heavy pressure public land and were after a mature buck they knew was in the area..They set up in a way that they thought would work and the buck came out late afternoon and worked towards them,just checking things out as big bucks do..Then he hit their scent stream and it took him less then a second to do a 180 and bolt out of there. 

The guys were surprised and kept dropping milkweed and when the wind died down the milkweed would drift to their 12 o'clock,as it did when the wind was up,but when it hit this little gully it would make a 90° turn and follow that instead,and that was what got them busted. The older the buck the better they know exactly where to be to scent check an area.

Using milk weed while accessing your hunting area is a good idea too. I think dan infalt talked about bumping a buck out of a bowl where he didnt expect one to be at all. But he said as he walked around the bowl he kept dropping milk weed and it always ended up where the buck bed was.

[Kmartinson]

Yeah buddy

[suburbanfarmer]

I hate the creek bottom bowls/valleys. I can get deer pictures out of it but never a deer ...lol

[Northcountryman]

15 hours ago, BowmanMike said:

Good summary moog..Deer tend to bed high in the a.m. to take advantage of the rising thermals..A strong wind will override thermals,but when the wind stops thermals take over. Milkweed is the best way to see what really happens. Creek bottoms are very difficult to hunt because the wind tends to swirl there,especially if it is a narrow valley.

The hunting public had a great video where they were on some heavy pressure public land and were after a mature buck they knew was in the area..They set up in a way that they thought would work and the buck came out late afternoon and worked towards them,just checking things out as big bucks do..Then he hit their scent stream and it took him less then a second to do a 180 and bolt out of there. 

The guys were surprised and kept dropping milkweed and when the wind died down the milkweed would drift to their 12 o'clock,as it did when the wind was up,but when it hit this little gully it would make a 90° turn and follow that instead,and that was what got them busted. The older the buck the better they know exactly where to be to scent check an area.

Using milk weed while accessing your hunting area is a good idea too. I think dan infalt talked about bumping a buck out of a bowl where he didnt expect one to be at all. But he said as he walked around the bowl he kept dropping milk weed and it always ended up where the buck bed was.

I have no doubt that this tends to be true but, where I hunt , pattern suggests they are doing the opposite . Over the years , the guys who have been hunting this area a long time all say That they see bucks come down from the higher ridge areas in the early morning and appear either to be be heading down to the creek bottom , or, traveling parallel to the mid level ridges from East to west . I can’t figure it out . I think they like to bed in some tough to reach areas kind of near the creek bottom but , not necessarily in it due to its inaccessibility / very little hunting pressure there .

Edited December 20, 2020 by Northcountryman