Podcast on Elk Biology

For those that geek out on this stuff, you might want to check out the Cutting The Distance podcast #42 with Jason Phelps and BYU bio-faculty Brock McMillan. Lots of good data from studies being conducted in the state.
Highlights
- Contra to a familiar belief, all data shows there is only one estrus cycle for elk and deer.
- % of cows that come into estrus each year can vary greatly (61% to 92%) leading to pregnancy variations (56% to 90%)
- 300+ elk births tracked, zero had twins
- No such thing as a "old, dry" cow, but often have calf every other year.
- 10% of antler size for a bull elk is determined by health of the mother while in utero. Another 10% determined by nutrition during antler growth cycle.
- Antler size of bull peaks at 7yrs and is 90% of max by age 6 (mentioned deer was 4-5).

I apologize in advance if I misstated anything, but it was very interesting. I'm not sure how it would differ by region, but it seems pretty general. There was discussion on managing bull/cow ratios and opportunity vs quality, showing how difficult the biologists' jobs are. I need to listen to #40 as it has some discussion on moon phases
This surprised me as I've read a lot of studies that are "Contra" to this study on one estrus cycle.
I didn't listen to the pod cast but thought I'd throw this out there.

I believe these elk were from the National Bison range in Montana. Wild ones then put in pens for study.


Abstract​

Groups of wild cow elk were confined during the breeding season in 1954, 1955, and 1956. A bull was introduced to the cow pen each day and all behavior observed. The use of a vasectomized bull in the early part of the season permitted recurrence of estrus. The approach of estrus was not predictable by any characteristics of the bull or cow. In most instances, sexual receptivity in the cow seemed to commence abruptly. A typical manner of behavior in the sexually receptive cow was described. Copulation required an average of 4 mountings by the bull in a period which averaged 7 minutes. Postcopulatory behavior in which a vaginal discharge was voided was described. Evidence was obtained which indicated that elk may remain in heat for 17 hours. The average interval of recurrent estrus was 21.2 days. One cow apparently had 4 recurrent estrums, 3 other cows had 3 each. /// Wilde Wapitihirschkühe wurden in den Jahren 1954-1956 vorübergehend rudelweise gegattert; täglich liess man einen Hirsch herein und beobachtete alles Verhalten. Da zu Beginn der Brunftzeit ein vasektomierter Hirsch eingelassen wurde, konnte man die Aufeinanderfolge von Brunften beobachten. - Der Oestrusbeginn war weder am Verhalten des Hirsches noch an dem der Tiere vorauszusagen. Der offenbar ganz plötzliche Beginn ihrer Paarungsbereitschaft liess sich an einem näher beschriebenen Geschlechtsverhalten erkennen. Meist sprang der Hirsch viermal binnen 7 Minuten; eine dem Sprunge folgende Scheidenentleerung wurde beschrieben. Das Tier bleibt 17 Stunden paarungsbereit; bis zum nächsten Oestrus vergingen in Mittel 21.2 Tage. Ein Tier hatte offenbar vier, die anderen hatten drei aufeinanderfolgende Brunften.
 
Also, body fat percentage operates much like an on/off switch for ovulation during estrus. It really is kind of an all or none type phenomena.

There either is enough body fat for ovulation or there isn’t.
 
This surprised me as I've read a lot of studies that are "Contra" to this study on one estrus cycle.
I didn't listen to the pod cast but thought I'd throw this out there.

I believe these elk were from the National Bison range in Montana. Wild ones then put in pens for study.


Abstract​

Groups of wild cow elk were confined during the breeding season in 1954, 1955, and 1956. A bull was introduced to the cow pen each day and all behavior observed. The use of a vasectomized bull in the early part of the season permitted recurrence of estrus. The approach of estrus was not predictable by any characteristics of the bull or cow. In most instances, sexual receptivity in the cow seemed to commence abruptly. A typical manner of behavior in the sexually receptive cow was described. Copulation required an average of 4 mountings by the bull in a period which averaged 7 minutes. Postcopulatory behavior in which a vaginal discharge was voided was described. Evidence was obtained which indicated that elk may remain in heat for 17 hours. The average interval of recurrent estrus was 21.2 days. One cow apparently had 4 recurrent estrums, 3 other cows had 3 each. /// Wilde Wapitihirschkühe wurden in den Jahren 1954-1956 vorübergehend rudelweise gegattert; täglich liess man einen Hirsch herein und beobachtete alles Verhalten. Da zu Beginn der Brunftzeit ein vasektomierter Hirsch eingelassen wurde, konnte man die Aufeinanderfolge von Brunften beobachten. - Der Oestrusbeginn war weder am Verhalten des Hirsches noch an dem der Tiere vorauszusagen. Der offenbar ganz plötzliche Beginn ihrer Paarungsbereitschaft liess sich an einem näher beschriebenen Geschlechtsverhalten erkennen. Meist sprang der Hirsch viermal binnen 7 Minuten; eine dem Sprunge folgende Scheidenentleerung wurde beschrieben. Das Tier bleibt 17 Stunden paarungsbereit; bis zum nächsten Oestrus vergingen in Mittel 21.2 Tage. Ein Tier hatte offenbar vier, die anderen hatten drei aufeinanderfolgende Brunften.
I didn’t want to portray it as an absolute or their body doesn’t do it. It may be possible, the guest just described it as not happening at scale. There is a peak and fat right tail, but no second peak. They were measuring this based on calf birthing dates and counting back. Maybe it is health (certainly not controlled for in confined cows) or something else we just don’t fully understand.
 
I think the word “peak” needs some clarification. The graph shows it isn’t a true peak or maximum until later years. But it also shows that by an age most would call maturity, an animal is 90-something percent of what it would ever be. If a bull is shot at 6.5yrs old and scored 320 (eliminating the nutrition variable- so saying it was good year) thinking that bull would have been 380-400 in two years is not supported by the data. Impossible for a bull to grow that much? No, but very rare. Same for deer. Really big animals are simply rare.

I’m not saying that there is no benefit to managing for age class and antler size, because older animals will be bigger and thereby increase the average. But it doesn’t mean there will be 180-200 inch bucks or 400in bulls in every section. In fact, the benefit may be temporary because more deer eventually degrades the habitat conditions and the females end up in less than ideal conditions which also impacts antler size. It is a tough balancing point.

I looked through the Freeman study and think it is pretty solid. A hunter could argue any single animal “would have been a monster” in two or three years, and we could never know because the animal is dead. If I had to bet money on it, I bet with what the data says.

Side note, I was listening to a podcast where the guide said the state’s (AZ I think) aging was wrong because he had a bull on trail camera for a certain number of years and the state said it was younger. Maybe there was a mistake in the lab, maybe it was a different bull, who knows. But it shows hunters have strong opinions on things that are hard to shift. Often wrong but never in doubt. 😉
I agree, but I would also argue that there is a big difference than a 163 inch mule deer and one that is 180, especially when a dispassionate amount of those 17 inches is in mass. That being said, I don't think game department should manage for 6 year old or better bucks. Just not a wise use of resources. Nor should they justify managing for younger bucks by claiming that deer have peaked at age four so we might as well shoot them.
 
Another side note. Here is a longitudinal study (same deer over years) on a recent mule deer antler growth in Texas. Average shows the same thing as mentioned previously, but the variability is crazy. You can see some deer that looked like they were on the path to being monsters at 3.5 and then they mean reverted, same with some that looked weak early. full read here https://issuu.com/texaswildlifeassociation/docs/2020-12-december_proof3_final/s/11364007

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That is close to what I see also. I would add that there date gets a little thin past 6 1/2. Many of the bucks I have watched that lived past 8 1/2 also grew there best set of antlers late in life. Still those antlers were not much bigger than those years earlier, Maybe a few percent in terms of inches, but the wall appeal was much better.
 
I recently listened to a podcast that cited a study out of Sweden that postulated, in humans, if a male child experienced starvation between 10 and 12 years of age, his grandchildren would show lower levels of heart disease and coronary problems.

Podcast discussing genes and activation of certain genes.

My point is that some of this is much more complicated and difficult to glean predictable results.
 
I recently listened to a podcast that cited a study out of Sweden that postulated, in humans, if a male child experienced starvation between 10 and 12 years of age, his grandchildren would show lower levels of heart disease and coronary problems.

Podcast discussing genes and activation of certain genes.

My point is that some of this is much more complicated and difficult to glean predictable results.
Well I guess I will be saving on some groceries in the future
 
I agree, but I would also argue that there is a big difference than a 163 inch mule deer and one that is 180, especially when a dispassionate amount of those 17 inches is in mass. That being said, I don't think game department should manage for 6 year old or better bucks. Just not a wise use of resources. Nor should they justify managing for younger bucks by claiming that deer have peaked at age four so we might as well shoot them.
That's the problem, the studies are done and then the various Departments take it as the gospel and start managing based on one particular study.

They tried it in Pronghorn here thanks to one study and the public was not happy about it. Hunt quality went south, populations went south, and I hope the lesson was learned. Probably not, since the study was done by the second person to ever walk on water.
 
I agree, but I would also argue that there is a big difference than a 163 inch mule deer and one that is 180, especially when a dispassionate amount of those 17 inches is in mass. That being said, I don't think game department should manage for 6 year old or better bucks. Just not a wise use of resources. Nor should they justify managing for younger bucks by claiming that deer have peaked at age four so we might as well shoot them.
Not sure we are arguing anything, but I don't know how else to manage a quality unit other than to average age. It doesn't change the fact that a 180+ mule deer is rare animal, just lets a few more stretch to see if they can reach it. This reveals Montana's problem with harvest data. Even if the surveys are accurate, just measuring based on points doesn't generate robust enough data. My general conclusion is even with good data, this stuff is hard. One example is highlighted by decline in quality buck size in MT 270 and the addition of permits to take smaller mule deer (3pts or fewer on one side) a few years ago. I think most biologist are honest in saying they don't know and we should be wary those that try to appear they do. But equally, hunters seem to think they "know" everything, and mostly they are full of manure.

@Buzz, I don't (and I would guess you don't) think MT and WY are comparable even if they are in similar situation on MD populations. What is becoming clear is we can't "bank" mule deer, and certainly can't antelope. My biggest concern is that weather/moisture is showing extreme volatility which impacts habitat which impacts herd condition and we have limited a herd's ability to adapt to the extreme events of drought or cold/snow. I don't know how good adaptive harvest management works in that environment other than every state sets tag numbers and runs draws in June. Hunters have to support an approach that will allow the animals to rebound quickly when conditions improve, which probably means less opportunity. Some just don't want to do that.
 
Not sure we are arguing anything, but I don't know how else to manage a quality unit other than to average age. It doesn't change the fact that a 180+ mule deer is rare animal, just lets a few more stretch to see if they can reach it. This reveals Montana's problem with harvest data. Even if the surveys are accurate, just measuring based on points doesn't generate robust enough data. My general conclusion is even with good data, this stuff is hard. One example is highlighted by decline in quality buck size in MT 270 and the addition of permits to take smaller mule deer (3pts or fewer on one side) a few years ago. I think most biologist are honest in saying they don't know and we should be wary those that try to appear they do. But equally, hunters seem to think they "know" everything, and mostly they are full of manure.

@Buzz, I don't (and I would guess you don't) think MT and WY are comparable even if they are in similar situation on MD populations. What is becoming clear is we can't "bank" mule deer, and certainly can't antelope. My biggest concern is that weather/moisture is showing extreme volatility which impacts habitat which impacts herd condition and we have limited a herd's ability to adapt to the extreme events of drought or cold/snow. I don't know how good adaptive harvest management works in that environment other than every state sets tag numbers and runs draws in June. Hunters have to support an approach that will allow the animals to rebound quickly when conditions improve, which probably means less opportunity. Some just don't want to do that.
The problem with declining numbers and quality of bigger bucks in 270 is not a function of habitat. It's a function of poaching, legal native Americans harvesting mature bucks, and over issuing tags.

The habitat in 270 is probably better now than the 60's and 70's. The genetics are still there, but again if the top end bucks are creamed when they even approach 170 and less than 6 years old, you're not going to keep quality.

I agree that in some areas the habitat may be an issue. But look at the front, historically and even recently the best big mule deer buck factory in Montana. I would argue since the scapegoat burned, it's better now than the 60's. The front is largely undeveloped so that's not the problem. The genetics are still there.

The problem is the same thing there, constant pounding in mule deer bucks from September through December. Better glass, tougher hunters, better rifles, and a long season. Those deer are flat $##&ed, they can only hide for so long. Once again as soon as they reach 4.5 their chances of making it to their potential are extremely low.

Throw in some poaching of the top end animals, it's surprising any make their potential.

I'm not ready to say it's mostly a habitat related issue in many cases. Certainly is in some places, but my question is why are there still no big bucks in areas of Montana with stellar habitat? I already answered that above.
 
Not sure we are arguing anything, but I don't know how else to manage a quality unit other than to average age. It doesn't change the fact that a 180+ mule deer is rare animal, just lets a few more stretch to see if they can reach it. This reveals Montana's problem with harvest data. Even if the surveys are accurate, just measuring based on points doesn't generate robust enough data. My general conclusion is even with good data, this stuff is hard.
Using the B&C gross score has problems for these studies.
I am a firm believer in the B&C scoring system, it is by far the best system out there for many reasons, but if your goal is to study the growth of antlers with respect to age of bucks the B&C scoring system is going to skew your data. In deer and elk B&C puts more weight on long points than it does mass. This could account for much of the reason there is only a 10% increase in antler size from age 4 to later in life. I have a hunch that if a measuring system that put more weight on mass the increase would be much greater than 10%. Also using gross score inflates the value for non typical points. Non typical points are often unpredictable at best. I suspect that one of the reason the Texas study is so messy is do to non typical points.
 
One example is highlighted by decline in quality buck size in MT 270 and the addition of permits to take smaller mule deer (3pts or fewer on one side) a few years ago.

Do you have any more info on this? I'd be interested in learning more on it.
 
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Do you have any more info on this? I'd be interested in learning more on it.
Not sure what you mean. I was simply saying that FWP addressed the decline in average quality, real or perceived, in the unit by creating a tag for smaller bucks. It would not have been my first guess on what should be done, but I’m not the professional. I don’t have much info and have never talked to the bio. Just found it interesting and would love to hear more from them. I also wonder how it has worked out. I think it has been 4 yrs? Again though, memory may fail me.
 
Not sure what you mean. I was simply saying that FWP addressed the decline in average quality, real or perceived, in the unit by creating a tag for smaller bucks. It would not have been my first guess on what should be done, but I’m not the professional. I don’t have much info and have never talked to the bio. Just found it interesting and would love to hear more from them. I also wonder how it has worked out. I think it has been 4 yrs? Again though, memory may fail me.

I guess I'm confused by what the goal of adding the 3 point tag was. It was to increase average buck size?
 
Not sure what you mean. I was simply saying that FWP addressed the decline in average quality, real or perceived, in the unit by creating a tag for smaller bucks. It would not have been my first guess on what should be done, but I’m not the professional. I don’t have much info and have never talked to the bio. Just found it interesting and would love to hear more from them. I also wonder how it has worked out. I think it has been 4 yrs? Again though, memory may fail me.
yea, not so fast. The reason I got through my discussions with the bio's and those that pushed this, was opportunity.

There were a lot of people seeing older age class 3 point bucks doing the breeding, and the hunters where looking for 4 points or better even if the buck was smaller/younger. There has been a push, by the department (sense going unlimited) to offer more tags.

Also, (even though CWD isn't in the HD) the department has handed down their orders for killing more deer so this was a good way of moving the goal posts and doing that.

Carry on.
 
yea, not so fast. The reason I got through my discussions with the bio's and those that pushed this, was opportunity.

There were a lot of people seeing older age class 3 point bucks doing the breeding, and the hunters where looking for 4 points or better even if the buck was smaller/younger. There has been a push, by the department (sense going unlimited) to offer more tags.

Also, (even though CWD isn't in the HD) the department has handed down their orders for killing more deer so this was a good way of moving the goal posts and doing that.

Carry on.
Ok. But 15 deer?
 
Do you know what kind of bucks have been getting killed on this permit? What the success rate has been?
Not personally. It is 3 pts or fewer one side and Gohunt shows success is around 60%. The only support for the #s is that there is mandatory check for that tag.
I kind of liken the decision to spike only tags for elk or brow tine requirements. It is just interesting to see how different states do different methods.
 
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