Another weird trend in data

[BSK]

I found a sudden and perplexing change in my trial-cam data over the years. Going back as far as I have the data entered (2011 as of this posting), the percent of November older buck images captured in daylight ran a consistent 17-19% year after year. Then suddenly, starting in 2017, the percentage jumped up into the low to mid 30% range and has stayed that way. I assumed this must have been a sudden change in camera placement, but going back and looking at the camera locations, I'm still using the exact same scrapes and concentration points today as I was in 2011. I looked at a possibility of camera manufacturer and design differences, and that's not it either. No sudden change in camera type starting in 2017. No major change in habitat starting in 2017. I haven't figured this one out yet, but I'm going to have to look into changes in our hunting style and pressure. But a sudden and consistent change in daylight older buck activity (increasing around 15%) is pretty significant.

 

[Ski]

That's dang near double! Could it be that your hunting habits enhanced buck age structure?

 

[CrossVolle]

I guess nonspecific to your farm, but has there been any major habitat changes within a couple miles? logging? Crop fields left to fallow? Has the pressure on surrounding properties increased?


Seems it could be a plethora of things. But interested in what you find.

 

[BSK]

That's dang near double! Could it be that your hunting habits enhanced buck age structure?

Buck age structure is virtually unchanged since 2004.

 

[BSK]

I guess nonspecific to your farm, but has there been any major habitat changes within a couple miles? logging? Crop fields left to fallow? Has the pressure on surrounding properties increased?


Seems it could be a plethora of things. But interested in what you find.

This is going to take some serious detective work.

 

[TheLBLman]

Has the pressure on surrounding properties increased?

I'll bet you a dollar against a donut, the surrounding property pressure has dropped significantly.

My theory, this is the #1 reason for the increased sightings.

And it's not just the hunting pressure decreasing as we normally think, but also the "type" hunting pressure. As more & more hunters are voluntarily passing yearling & 2 1/2-yr-old bucks, I believe this is "conditioning" the 3 1/2 & older bucks to be LESS hunter wise, and move around more during daylight.

Conversely, with a heavy doe harvest, we see older doe going almost totally nocturnal.

 

[CrossVolle]

I'll bet you a dollar against a donut, the surrounding property pressure has dropped significantly.

My theory, this is the #1 reason for the increased sightings.

And it's not just the hunting pressure decreasing as we normally think, but also the "type" hunting pressure. As more & more hunters are voluntarily passing yearling & 2 1/2-yr-old bucks, I believe this is "conditioning" the 3 1/2 & older bucks to be LESS hunter wise, and move around more during daylight.

Conversely, with a heavy doe harvest, we see older doe going almost totally nocturnal.

Totally plausible.

 

[BSK]

I'll bet you a dollar against a donut, the surrounding property pressure has dropped significantly.

My theory, this is the #1 reason for the increased sightings.

And it's not just the hunting pressure decreasing as we normally think, but also the "type" hunting pressure. As more & more hunters are voluntarily passing yearling & 2 1/2-yr-old bucks, I believe this is "conditioning" the 3 1/2 & older bucks to be LESS hunter wise, and move around more during daylight.

Conversely, with a heavy doe harvest, we see older doe going almost totally nocturnal.

You may very well be right TheLBLman. Surrounding pressure has been dropping for some time. And I don't know anyone in the area shooting yearling bucks (except for my one baiting neighbor. He'll shoot anything with it's nose in the corn pile).

 

[BSK]

I'll bet our hunting style has changed as well. We've been adding a lot of ladder stands to the property. We're also not placing as many hours of hunting pressure on the property as we used to. Less time in the stand, spread over a much wider arrangement of stands, may be playing a role.

 

[LenS]

Would switching to video instead of still photos have allowed you to capture bucks you otherwise would've missed?

 

[fairchaser]

I would think that allowing the age structure to increase has some impact as well. More older bucks equals more competition and more searching in the daylight. It's possible that you reached a tipping point in your age structure.

 

[TheLBLman]

Would switching to video instead of still photos have allowed you to capture bucks you otherwise would've missed?

Would think this is at least a small factor.
Also, today's cams have a little better triggering range than they did a few years ago.

 

[BSK]

Would switching to video instead of still photos have allowed you to capture bucks you otherwise would've missed?

I think a few (bucks way off in the background that wouldn't be noticed in a still image but can be seen moving in a video). But I only switched to video in 2020.

 

[BSK]

I would think that allowing the age structure to increase has some impact as well. More older bucks equals more competition and more searching in the daylight. It's possible that you reached a tipping point in your age structure.

Nope. No change in age structure since 2004. A real flatline.

 

[TheLBLman]

Nope. No change in age structure since 2004. A real flatline.

But maybe hunters are killing more older bucks,
keeping that age structure similar to a real flatline?
More 3 1/2's getting a pass, more 4 1/2's getting killed?

 

[JN]

What area of the state is the data coming from?

 

[fairchaser]

Nope. No change in age structure since 2004. A real flatline.

Curious how you know? Observations?

 

[Rem7600]

I think you'll have a weird line of events that added up to this, not 1 specific thing that changed. Maybe a combination of things that did it. You'll figure it out one day and say how did I not realize that,

 

[BSK]

What area of the state is the data coming from?

Western Middle TN.

 

[Remington700]

Has the browse line changed much or the thickness of the property? I ask because as my property opens up and pressure around it has dropped. I am actually seeing less bucks than I use to. I am actually thinking about select cutting to make it grow back thicker and maybe bring the deer back into it more. My daughter, who also hunts, is against it because now that it is opening up we are getting more turkey. It's kind of a double edged sword.

 

[BSK]

Curious how you know? Observations?

24 years of season-long camera censuses. Here's the buck age structure data since 2003 on a 3-Year Running Mean (which is used to take out the typical year-to-year fluctuations caused by smallish data sets). I have data back to 1999, but I tend not to compare it to the data 2003+ because the earlier censuses were run using film cameras, hence the settings on the cameras were very different due to worries about running out of film. From 2003 onwards I was using digital cameras and could "let 'er rip" with picture numbers.

 

[fairchaser]

24 years of season-long camera censuses. Here's the buck age structure data since 2003 on a 3-Year Running Mean (which is used to take out the typical year-to-year fluctuations caused by smallish data sets). I have data back to 1999, but I tend not to compare it to the data 2003+ because the earlier censuses were run using film cameras, hence the settings on the cameras were very different due to worries about running out of film. From 2003 onwards I was using digital cameras and could "let 'er rip" with picture numbers.

Very interesting data set. I see what you mean! Have you ever tried to figure out what percentage of bucks totally avoid the camera? I would think most bucks have grown up with cameras now and are sort of used to them. I'm not sure if this would skew the results or change over time. The daylight pics are perplexing though. It could very well be the result of something outside the influence of man or hunters.

 

[BSK]

Have you ever tried to figure out what percentage of bucks totally avoid the camera?

The only way I know of to estimate what percentage of bucks are not captured on film is to use a modified version of "Mark-Recapture" statistics. With Mark-Recapture studies, animals are captured, all are marked and then released. Later, animals are recaptured and the percent of the second capture that were marked from the first capture gives you an estimate of what percentage of the total population was captured the first time (generally, these later captures are run over and over to get a good estimate). So if 30% of the animals recaptured are marked, then that first capture caught about 30% of the total population.

I can use the bucks captured on film as the "first capture," and then bucks harvested as the recapture, and the number caught on film previous to harvest as the "marked" deer. Since 2003, of the 63 bucks harvested, all but 2 were "marked" (previously caught on film). So those bucks caught on film each year represent around 97% of the total buck population. That's a pretty good census.

 

[fairchaser]

The only way I know of to estimate what percentage of bucks are not captured on film is to use a modified version of "Mark-Recapture" statistics. With Mark-Recapture studies, animals are captured, all are marked and then released. Later, animals are recaptured and the percent of the second capture that were marked from the first capture gives you an estimate of what percentage of the total population was captured the first time (generally, these later captures are run over and over to get a good estimate). So if 30% of the animals recaptured are marked, then that first capture caught about 30% of the total population.

I can use the bucks captured on film as the "first capture," and then bucks harvested as the recapture, and the number caught on film previous to harvest as the "marked" deer. Since 2003, of the 63 bucks harvested, all but 2 were "marked" (previously caught on film). So those bucks caught on film each year represent around 97% of the total buck population. That's a pretty good census.

I'm always surprised by bucks that get killed that no one had pics of and other bucks that get their pics taken all over the plantation. But by and large, they generally get their pics taken at least once. That's one big reason I don't believe in Bigfoot! Where are the pics?

 

[JCDEERMAN]

I'm always surprised by bucks that get killed that no one had pics of and other bucks that get their pics taken all over the plantation. But by and large, they generally get their pics taken at least once. That's one big reason I don't believe in Bigfoot! Where are the pics?

Yep and all the guides and hunters

 

[BSK]

I'm always surprised by bucks that get killed that no one had pics of and other bucks that get their pics taken all over the plantation.

Now normally, we have a much higher success rate killing bucks that are photographed very frequently. But now and then we kill one that has been photographed just once. But the one's that really fry my brain are the bucks that are photographed over and over and over, yet no one ever sees them with their own eyes. It doesn't seem possible.

 

[Ski]

I'm always surprised by bucks that get killed that no one had pics of and other bucks that get their pics taken all over the plantation. But by and large, they generally get their pics taken at least once. That's one big reason I don't believe in Bigfoot! Where are the pics?

I think those tend to be the drifters. I see it happen while hunting and on cam at least once per season. Bucks will move through the property once on a straight line, maybe stepping past a cam & maybe not. Then they're gone forever. I saw one in person this season like that and he never was on cam nor had I ever seen him before or after. Who knows where they come from, where they're going, or how far they travel? It's an enigma.

On the flip, I have bucks that are regulars but in varying intervals and timelines. Summer bucks aren't necessarily fall bucks and they're not necessarily winter bucks, but they show up often enough within their respective timeframes that I recognize and expect it. And at least one or two bucks at any given time seem to be permanent party residents. They're around any time of year. But all of them disappear for days or weeks at a time so I can only assume they are somebody else's enigma bucks.

The bucks I like to hunt are the homebodies. I get familiar enough with them to know their tendencies and for lack of better word they are "easier" to kill. There was a time I'd get excited about seeing a giant on cam, and I'd start making all kinds of plans on how I'd kill him. Mind you it might only be one pic at 3:30am and never again. Looking back I can see how ridiculously naive I was. Never once have I killed one of those bucks. These days I only get excited when I see a buck every part of the year and on every camera on the property every time of day because I know that means my property is his home, and when/if he reaches maturity I have a reasonable chance at killing him. I usually have one like that to hunt every year or every other year. He may not always be giant like the mysterious random drifters, but often enough for me he is.

 

[Popcorn]

I didnt see this so Ill ask, Are you seeing the same bucks more often or more bucks in all? The results could look the same for totally different reasons.

 

[BSK]

I didnt see this so Ill ask, Are you seeing the same bucks more often or more bucks in all? The results could look the same for totally different reasons.

Our deer (and buck) population has varied over time and is closely linked to cover/browse habitat. Each time we cut timber, the population spikes a couple years later, as natural food production peaks. However, the doe and fawn population seem to be more influenced by this change in habitat than the bucks. This is probably due to the fact our bucks are very transitory. Few of the bucks we have using the property during the fall hunting season are actually residents. They show up in fall, and especially for the rut, and then vanish. Although we see considerable fidelity to the property each fall (same bucks coming back for the rut year after year).

Below are two graphs, the total census population and the buck census population. Notice how much more dramatic the total population is linked to timber-cutting than the buck population. The size of each population spike linked to timber removal is closely tied to the amount of timber cut. Cut a small percentage of the timber, you get a small bump in population. Cut a large section, you get a large bump.

 

[TRIGGER]

2 buck limit?