Question on enclosure population dynamics

[QDM4fun]

I was going to try to gain some insight on this from the "perils" thread, but it went away.

I manage a lot of properties and high fences are becoming more popular here. I have had several clients bring up the subject and I feel I need some information from some more knowledgable people.

My main concern is the population and age structure in a smaller enclosure. Here in Mississippi an enclosure has a minimum size of 300 ac. I have been playing with the numbers trying to project a target herd size and age structure to see what size an enclosure must be to meet the goals of the client.

In order to harvest 2, 6 1/2 yo bucks each year, it looks like we will need to run 1 deer per 5 ac in a 300 ac pen, with a 5:1 buck:doe ratio. Is that ratio realistic? Can 10 does produce 10 buck fawns/year? This is my thoughts on the target buck age structure

Age. Pre-season Post-season

Fawn. 10 10
1.5. 10. 10
2.5. 10. 8
3.5. 8. 6
4.5. 6. 4
5.5. 4 2
6.5. 2. 0

This would require harvest of 10 bucks annually, 2 from each age class.

Please give me your thoughts on this. Thanks

[STGS]

Why are you harvesting from your younger age classes? You will also have some natural mortality, so factor that in as well. I personally, would not kill anything from the 1-4 age classes and focus on the mature stuff. Less guessing and more opportunity for the bucks to show their potential.

Why such a skewed doe to buck ratio? A 1:1 ratio would allow you to have 30 bucks spread out over a normal age structure. You could even go with 1 doe to 1.5 bucks and allow for 40 bucks and 20 does. You only need enough does to produce enough buck fawns to replace those killed (bullet or mother nature) each year.

[Dudley]

You are counting fawns as part of your population count? Fawning rate, and their survival, make it hard to get an accurate count. Most people include adult deer only when considering buck/doe ratio and deer per acre.

[QDM4fun]

Why are you harvesting from your younger age classes? You will also have some natural mortality, so factor that in as well. I personally, would not kill anything from the 1-4 age classes and focus on the mature stuff. Less guessing and more opportunity for the bucks to show their potential.

Why such a skewed doe to buck ratio? A 1:1 ratio would allow you to have 30 bucks spread out over a normal age structure. You could even go with 1 doe to 1.5 bucks and allow for 40 bucks and 20 does. You only need enough does to produce enough buck fawns to replace those killed (bullet or mother nature) each year.

If we carried 30 bucks spread evenly over 6 age classes, I guess we need to plan on taking out some 1.5 year olds, then carry the remainder from there?

My thoughts are that the 300 ac / 60 deer may not be a large enough enclosure.

[treestand]

I think 5 acre per deer is ok but would mean a lot of supplemental feeding probably from a combination of food plots and protein. I'm no expert on high fence ranches but do know that it takes about 10 acres per deer in low fence areas.

[JeffJ]

I think you are underestimating natural attrition.

[Karmstrong]

I have a lot of the same questions and was very disappointed on the direction that other took Sippy's thread. Looking to do the same on 260 acre place that I have and want to make sure it will support what I am trying to do. Have hunted on a 1000 acre HF place that we were taking off 15 bucks each year. So with simple math I should be able to take 3.75 bucks per year. This includes culls, management, and trophies. Any information will be helpful in making a decision.

[Karmstrong]

Can anyone provide any experience on natural mortality.

[millman]

Why are you harvesting from your younger age classes? You will also have some natural mortality, so factor that in as well. I personally, would not kill anything from the 1-4 age classes and focus on the mature stuff. Less guessing and more opportunity for the bucks to show their potential.

Why such a skewed doe to buck ratio? A 1:1 ratio would allow you to have 30 bucks spread out over a normal age structure. You could even go with 1 doe to 1.5 bucks and allow for 40 bucks and 20 does. You only need enough does to produce enough buck fawns to replace those killed (bullet or mother nature) each year.

x2

from 0-6.5 I would be very concerned about mother nature

[QDM4fun]

I agree that 1 per 10 ac would be better, but that would require twice as many acres for the same population.

As for mortality, I understand that there will be some unknowns that will take a while to understand. If we assume a 10-20% natural mortality rate, that only adds to the number we would have to carry to reach the goal.

I'm really trying to get a good grasp on reasonable expectations. I don't want a landowner to spend $60-$100 K on fence only to find they don't have the acres to produce the numbers they want.

[BolilloLoco]

Natural Mortality can vary greatly from one ranch to another. 10-20% sounds reasonable. But it could end up being as high as 50%. Only one way to find out.

[bloodtrailer28]

Why are you harvesting from your younger age classes? You will also have some natural mortality, so factor that in as well. I personally, would not kill anything from the 1-4 age classes and focus on the mature stuff. Less guessing and more opportunity for the bucks to show their potential.

Why such a skewed doe to buck ratio? A 1:1 ratio would allow you to have 30 bucks spread out over a normal age structure. You could even go with 1 doe to 1.5 bucks and allow for 40 bucks and 20 does. You only need enough does to produce enough buck fawns to replace those killed (bullet or mother nature) each year.

Well said.

OP I would listen to ^^^ he knows his stuff and has grown some huge deer. Check out some of his threads and you can see he knows his stuff.

We leave more does than most on our place but we like carrying a bunch of deer. We do have to poor the feed to them and plant a bunch of plots but we enjoy seeing a bunch of deer and have a blast hunting them! We dont have near the size of most places with a TALL fence but we have an all native herd and are trying to work our way up. Hasnt been easy.

[STGS]

Another item to address is predator control. Be sure and teach your landowner(s) how to set snares (cable snares) for coyotes, bobcats and foxes. Predation can have a significant impact on your fawn crops and adult deer. This can be particularly impactful on small herds or during tough conditions.

You want to avoid having ultra low recruitment rates as that can create holes in your age structure.

[STGS]

If we carried 30 bucks spread evenly over 6 age classes, I guess we need to plan on taking out some 1.5 year olds, then carry the remainder from there?

My thoughts are that the 300 ac / 60 deer may not be a large enough enclosure.

300 acres is plenty large provided there is adequate cover, food and water. I suggest you consider supplemental feed (3-5 protein free choice protein feeders) and multiple 2-5 acre food plots (if feasible).

Carrying capacity varies by ranch and can vary from year to year on any given ranch. Supplemental feeding allows you to accomodate the same number of deer with varying range conditions. High fencing 300 acres without supplemental feed will likely force you to reduce the overall carrying capacity.

Good luck with your endeavor and enjoy the process. It can be frustrating at times, but also very rewarding as you begin to see the fruits of your labor.

[millman]

Are the properties you are working with adding genetics or trying to see where they get with the native deer they have? If these are "clients" you would sure want to know what the expectations after the $60-100k high fence is put up?