Does Buck Harvest harm herd recovery? Studies?

[WYelker]

I am struggling to find good clear data and studies on this issue. I know it is generally accepted that male harvest is not a limiting factor on herds and on herd recovery as long as the male to female ratio is high enough for the females to be bred.

Does anyone have good studies on this topic?

I know that the generally 12/100 buck to die ration is considered the low end and anything below that lead to open doe in the fall. I know that high pregnancy rates are the first step, then getting fawns on the ground next step then having fawns survive is the final. But where does buck harvest play into this equation?

Can you share articles/studies in this area?

 

[jt13]

The Penn State Deer-Forest Study/Blog may have some of the answers your looking for. I don't know of a another place with more easily digestable deer science.

Over the Hump

We're on the downhill side of the rut. More than half of females are now pregnant. The Rut Tracker is updated through November 19. Several readers have asked if the warm weather, or some other factor, has influenced breeding behavior this year as males seem to be moving less, and females...

www.deer.psu.edu

 

[antlerradar]

Would be interesting, Also would want to know if there is any increase in the number of does not getting bred first cycle, if the age of the bucks and if hunting pressure during the rut has any effect.
I lean on the side that 12/100 buck to doe ratio is enough to get the job done and that the health of the doe is a much bigger factor in pregnancy rates. I could however see where this could be an issue where deer density is low or where a big majority of the does are concentrated in a small area. An issue for minority of does that are not in the big concentrations and if those low density areas are receiving heavy hunting pressure.

 

[DFS]

Would be interesting, Also would want to know if there is any increase in the number of does not getting bred first cycle, if the age of the bucks and if hunting pressure during the rut has any effect.
I lean on the side that 12/100 buck to doe ratio is enough to get the job done and that the health of the doe is a much bigger factor in pregnancy rates. I could however see where this could be an issue where deer density is low or where a big majority of the does are concentrated in a small area. An issue for minority of does that are not in the big concentrations and if those low density areas are receiving heavy hunting pressure.

In 2012 at a public meeting someone asked what percentage of does get bred and maybe we shouldn’t be pressuring them during the rut. One of the biologists now retired piped up from the back obviously irritated with the question and said “100%” I’m sure he had a study of some sort.

 

[jt13]

In 2012 at a public meeting someone asked what percentage of does get bred and maybe we shouldn’t be pressuring them during the rut. One of the biologists now retired piped up from the back obviously irritated with the question and said “100%” I’m sure he had a study of some sort.

He was pretty close!!


"By far, the most popular question in the fall is "When is the rut in Pennsylvania?" To answer that question, the Game Commission collected breeding date information from road-killed does in the spring from 2000-2007. Fetus length from these unlucky does was measured. From these data, we can determine the age of the fetus. Since the gestation period of deer is about 200 days, knowing the age of the fetus allows us to estimate when conception took place.

Over 6,000 does were examined over this period. What did those unlucky does tell us? Nine out of 10 does were bred from mid-October to mid-December. And the peak of the rut occurred in mid-November.

Sexual maturity in doe fawns is linked to body size which is related to quality and quantity of food as well as birth date. Doe fawns reaching is critical size (80-90 lbs) come into estrous their first fall; but breed later than adult does. Peak breeding by fawns occurred in late November and early December. Nearly half of all fawn breeding occurred from December to February. This probably explains breeding activity observed by hunters after Thanksgiving.

Ninety-one percent of adult does and 26% of doe fawns were pregnant. The number of fawns conceived also varied by the age of a doe. Doe fawns generally had single fawns while adult does usually had twins. And triplets were rare."

When is the rut?

www.pgc.pa.gov

 

[wytex]

Sadly it sounds like WG&F is going to use those numbers on some mule deer herds to lower CWD prevalence. They want just enough bucks to get the doe bred and keep mature buck numbers down to lower cwd.
It is coming for some areas I think, regions with high cwd numbers.

 

[DFS]

Sadly it sounds like WG&F is going to use those numbers on some mule deer herds to lower CWD prevalence. They want just enough bucks to get the doe bred and keep mature buck numbers down to lower cwd.
It is coming for some areas I think, regions with high cwd numbers.

Montana has been managing for CWD before it even existed. It’s still here.

 

[JohnBud]

There has been some great research done on whitetails that was conducted over several decades at the Sandhill Wildlife Area in central Wisconsin. I have some paper copies of the reports but I have not yet been able to find any electronic copies to share. The Cliff Notes version is that hunter harvest of whitetail bucks, even with very high levels of hunter effort, is not a limiting factor for does getting bred. Population growth in Wisconsin whitetails is all about the number of doe tags issued. Every hunter in Wisconsin (more than 500,000) gets a buck tag over the counter based upon good science supporting this management strategy. Our whitetail herd is now estimated to be over 2,000,000. Just sayin.

 

[SAJ-99]

Might be difference between whitetails and mule deer. Whitetails can be very prolific and have higher densities in core habitat. It would be interesting to see how mule deer compare in the studies.

 

[Pahoundsman]

I read an article that said a buck was good for 8-12 does.That would make the 12/100 ratio about right. I think that would also depend on deer density. That was also a PA study,if that makes a difference.

 

[brymoore]

Might be difference between whitetails and mule deer. Whitetails can be very prolific and have higher densities in core habitat. It would be interesting to see how mule deer compare in the studies.

I’m not sure it would be that different because mule deer congregate together on winter range for the rut.

I’ve stood on Chukar slopes and watched the herds of mule deer does getting worked by the roaming bucks.

 

[Shangobango]

Would be interesting, Also would want to know if there is any increase in the number of does not getting bred first cycle, if the age of the bucks and if hunting pressure during the rut has any effect.
I lean on the side that 12/100 buck to doe ratio is enough to get the job done and that the health of the doe is a much bigger factor in pregnancy rates. I could however see where this could be an issue where deer density is low or where a big majority of the does are concentrated in a small area. An issue for minority of does that are not in the big concentrations and if those low density areas are receiving heavy hunting pressure.

I know I read a study or article with citations on this somewhere with respect to Whitetails.

If I remember correctly it was found that if the buck to doe ratio was skewed enough that it caused more does to be bred during a later cycle, sometimes even a third or fourth cycle occurred if the buck ratio was low enough. There was deer density considerations there too. Maybe it was the National Deer Association... I will see what I can dig up tonight.

My anecdotal evidence certainly supports this as does the dates of the mounts I have on the wall.

I will try and find that study or article.

 

[antlerradar]

I’m not sure it would be that different because mule deer congregate together on winter range for the rut.

I’ve stood on Chukar slopes and watched the herds of mule deer does getting worked by the roaming bucks.

not so much in Eastern Montana. If there are big concentrations of deer it is on alfalfa. Most deer have yet to migrate to winter range on turkey day unless there is an early winter.

 

[Shangobango]

I haven't came up with the study I remember yet. Had a crisis at work late yesterday.

Here are some articles and one older study, all on whitetailed deer

http://roberts.agrilife.org/files/2...ultsexratioreproductionwhitetaileddeer_13.pdf

https://deerassociation.com/late-rutting-activity-indicator-problems/

https://deerassociation.com/reality-doebuck-ratios/

https://www.msudeer.msstate.edu/ecology-of-the-rut.php

 

[rogerthat]

I don’t think whitetail deer and mule deer are similar enough in their habits nor habitat type preferences for studies to translate. More studies on mule deer are definitely needed in my opinion on all fronts. Whitetails can also vary greatly depending on habitat. I’m not sure some of those whitetail studies translate even to whitetails if the habitat is different enough.

 

[Shangobango]

I don’t think whitetail deer and mule deer are similar enough in their habits nor habitat type preferences for studies to translate. More studies on mule deer are definitely needed in my opinion on all fronts. Whitetails can also vary greatly depending on habitat. I’m not sure some of those whitetail studies translate even to whitetails if the habitat is different enough.

Yea, I think you are probably right. I think one of those articles even points out that the effects of skewed buck to doe ratios were more pronounced in some regions than others due to deer densities, habitat, agricultural practices, etc.

The one thing that seems to be pretty clear and widely agreed upon so far as whitetails go is that a more condensed breeding period is better for the herd.

I know here when I am seeing heavy rutting activity in March which is 2 or 3 months after the primary rut that there is a problem and I see that pretty much every year. And it ain't climate change or warm weather or none of that jazz. I think it is not enough bucks to service the does in a timely manner.

 

[R.K.]

I read an article that said a buck was good for 8-12 does.That would make the 12/100 ratio about right. I think that would also depend on deer density. That was also a PA study,if that makes a difference.

You have to remember- those numbers count fawns (assumed to be 50% bucks). So that 12/100 ratio, you might be as low as 4/100 adult bucks to doe. Have to watch their definitions To ensure you’re talking about the same thing.

Three kinds of lies- lies, damn lies, and statistics. This would be the latter.

And let’s not forget- timing of conception matters. Because you want your fawns to come out just right to maximize summer greenup, so they can enter winter in the best condition possible. So having a higher percentage of fawns dropping later might impact first winter survival, especially in later winters.