Buck-To-Doe Ratio Article

[blackbeard]

I finally found the article I was looking for. It was in the March 2008 Deer and Deer Hunting magazine. The title was “Buck-To-Doe Ratio: Too Many Does or Too Many Deer?”. The writers main point was that high buck to doe ratios were basically rhetoric and that there are not high buck to do ratios in most areas.

The writer referenced an article from the 1955 Journal of the New York State Fish and Game Journal by C.W. (Bill) Severinghaus. Mr. Severinghaus found that on average 109 buck fawns are born for every 100 doe fawns and that the highest a buck to doe ratio can get is 2.26 to 1 for a pre-hunt area. Pre-hunt meant after the previous year’s harvest, plus last year’s fawns being adults, plus this year’s fawns.
The writer used Severinghaus’s findings and gave the following example: Suppose you start with a fall population of 100 bucks, 100 does, and 100 fawns. If we assume 50% buck fawns and 50% doe fawns, and all bucks (antlered- not fawns) were killed and no adult does were killed the adult sex ratio would be 3:1. That is 50 antlered bucks and 150 adult does. Those 150 adult does would produce at least 150 fawns and the adult sex ratio would remain at 3:1, as long as the production remained at least at 1 fawn per doe.

So, let’s look at a few different scenarios:

Scenario 1- assumes that your property has 100 bucks, 100 does, that every adult buck will be killed, that no adult does will be killed by hunters, cars, or predators, that each adult doe will have 1 fawn, and that fawns will be 50% bucks and 50% does.

Year 1
Pre-fall (before hunting season) - 100 bucks, 100 does, 100 fawns
After season - 0 bucks, 100 does, 100 fawns
After fawns become adults – 50 bucks, 150 does, 0 fawns (3:1)

Year 2
Pre-fall (before hunting season) – 50 bucks, 150 does, 150 fawns
After season – 0 bucks, 150 does, 150 fawns
After fawns become adults – 75 bucks, 225 does, 0 fawns (3:1)

Scenario 2- assumes that your property has 100 bucks, 100 does, that every adult buck will be killed, that no adult does will be killed by hunters, cars, or predators, that each adult doe will have 2 fawns, and that fawns will be 50% bucks and 50% does.

Year 1
Pre-fall (before hunting season) - 100 bucks, 100 does, 200 fawns
After season - 0 bucks, 100 does, 200 fawns
After fawns become adults – 100 bucks, 200 does, 0 fawns (2:1)

Year 2
Pre-fall (before hunting season) – 100 bucks, 200 does, 400 fawns
After season – 0 bucks, 200 does, 400 fawns
After fawns become adults – 200 bucks, 400 does, 0 fawns (2:1)

Scenario 3- assumes that your property has 100 bucks, 100 does, that every adult buck will be killed, that no adult does will be killed by hunters, cars, or predators, that only half of the adult does will have 1 fawn, and that fawns will be 50% bucks and 50% does. This scenario is probably not typical because 50% of does would not miss out on getting bred.

Year 1
Pre-fall (before hunting season) - 100 bucks, 100 does, 50 fawns
After season - 0 bucks, 100 does, 50 fawns
After fawns become adults – 25 bucks, 125 does, 0 fawns (5:1)

Year 2
Pre-fall (before hunting season) – 25 bucks, 125 does, 62.5 fawns
After season – 0 bucks, 125 does, 62.5 fawns
After fawns become adults – 31.25 bucks, 156.25 does, 0 fawns (5:1)

Scenario 4- assumes that your property has 100 bucks, 400 does, that every adult buck will be killed, that no adult does will be killed by hunters, cars, or predators, that each adult doe will have 2 fawns, and that fawns will be 50% bucks and 50% does.

Year 1
Pre-fall (before hunting season) - 100 bucks, 400 does, 800 fawns
After season - 0 bucks, 400 does, 800 fawns
After fawns become adults – 400 bucks, 800 does, 0 fawns (2:1)

Year 2
Pre-fall (before hunting season) – 400 bucks, 800 does, 1600 fawns
After season – 0 bucks, 800 does, 1600 fawns
After fawns become adults – 800 bucks, 1600 does, 0 fawns (2:1)

[rthensley]

Those are some pretty extreme assumptions, but it is interesting.


Here is the problem we have in my part of Virginia. When I was growing up I was told that it was not a good idea to shoot a doe (as were most kids). The reasoning was that if you killed a doe, you removed at least two deer from the herd. The doe and her not yet born fawn. We still have "doe days" during gun season in Virginia. You can not kill does the entire gun season. You can only kill does on certain days.

Throwing out all the raw numbers and just looking at percentages.

If each year 50% of the bucks were killed & only 20% of the does were killed, wouldn't over time the percentage of does in the herd have to increase?

[rthensley]

Numbers are funny (especially to me). They are funny because when you do examples like the buck:doe ratio, everything depends on the numbers you use when you start.


Here are the numbers used by the article BB mentions for Year 1:

Pre-fall (before hunting season) - 100 bucks, 100 does, 100 fawns

To me, that is an extremely flawed set of numbers to begin with. Those numbers represent deer. Those deer represented to start the year had to be in the womb, or alive, in Year 0 (the year before Year 1). Dang, that sounds confusing. You know what I am trying to say. Those 300 total deer either had to be alive at the end of Year 0, or their mother had to be alive. They did not just materialize out of the air.

We need to figure out what numbers belong for Year 0 to see if the numbers given to start Year 1 make any sense.

Year 0

Pre fall ? bucks, ? does, ? fawns
After season ?, bucks, ? does, ? fawns
After grown fawns ? bucks, ? does, 0 fawns

(here are the numbers again)

Pre-fall (before hunting season) - 100 bucks, 100 does, 100 fawns

The easiest ones to figure out for Year 0 are the number of bucks & does after the fawns were grown. The number of bucks & does before season in Year 1 is the same number of bucks & does after the fawns were grown in Year 0. These numbers have to be 100. There is no other semi-logical way for it to be any other numbers. So Year 0 now looks like:

Year 0

Pre fall ? bucks, ? does, ? fawns
After season 0 bucks, ? does, ? fawns
After grown fawns 100 bucks, 100 does, 0 fawns

The author of the study has all the bucks being killed during season. So I went ahead and put a 0 in that place. Since all the bucks were killed in season, and there HAS to be 100 bucks after the fawns were grown (assuming a 50/50 split in the sex of the fawns), there HAS to be 200 fawns alive after the season. There can be no other number. We now have:

Year 0

Pre fall ? bucks, ? does, 200 fawns
After season 0 bucks, ? does, 200 fawns
After grown fawns 100 bucks, 100 does, 0 fawns

A HUGE problem! The numbers we have in place HAVE to be correct (I think). BUT, we don't have room for any does to be left alive after the season. Not possible.

Using the author's methods, there is NO way the numbers used to start Year 1 could be correct (remember..those numbers HAVE to be created by the author's own circumstances).


I did not look at the numbers for the other examples. I've spent way too much time on this anyway.

My 2 cents.

[blackbeard]

It's like the chicken and the egg. You got to start somewhere. Use whatever numbers you want to start and just see how it plays out. Another example based on what you said.

100 bucks, 300 does, 50% bucks are killed and 20% does are killed. So after hunting season you have 50 bucks and 240 does. Let's say half of the 240 does left are yearlings and have one fawn, and the other 120 adult does have twins. So now you have 50 bucks, 240 does, and 360 fawns. 50% of the fawns will be bucks and 50% will be does. So now we have 230 bucks and 420 does. That is a 1 to 1.82 buck to doe ratio.

The main point is that bucks being born every year at a rate pretty much equal with does so it is difficult to get a really high buck to doe ratio unless non-typical factors exist.

[rthensley]

I get what you are saying BB. Starting numbers have to come from somewhere.

But something in the way this study was done just does not clickwith me. For example, in the numbers you used in your last post, those numbers show the deer herd in that locality increasing by 62%. If breeding really did happen like we are talking about, there would be similiar increases in the herd size every year. We know that does not happen, so something has to be off.

Anyway, my thoughts are influenced by the deer herd in my part of Virginia. No doubt your deer herd numbers are different.

No way in my part of Virginia is the buck to doe ratio anywhere near 1:3 or even 1:5. I hate to say it about my fellow western Virginians, but too many of them will shoot anything with antlers (while letting most does walk). A buck deer down here is lucky to make it to 3 years of age. It is very typical for me, or other hunters, to hunt for a week down here and only see does (with maybe a spike thrown in).

Our part of the state probably kills a larger percentage of our bucks than you guys do because we have more days where you can hunt with a gun.

We have an early muzzleloader season from Oct 30 - Nov 12 (the only day you can shoot does is on Nov 6) and a late muzzleloader season from Dec 11 - Jan 1 (you can only shoot does on Jan 1). That is 36 days of muzzleloader hunting with only two days you can shoot does.

We also have a rifle season that runs from Nov 13 - 27. You can now shoot does from Nov 20-27. A few years ago you were limited to only shooting does on one of the rifle season days.

In my part of the state you are allowed to kill 2 bucks and 3 does. In the eastern part of the state you can kill 3 bucks and 3 does.

The state is trying to encourage the killing of more does. We can spend $18 and buy 6 antlerless tags. Yes. For every $18 you are willing to spend, you can kill an additional 6 does.

Maybe these things are the "non-typical" things you are talking about that can influence your buck to doe ratio.

[Split_G2]

First off, excellent discussion guys.

RT, I wouldn't necessarily call your situation a non-typical thing.....plain and simple, that is piss poor management at best. VDNR needs to seriously look at how other states(mainly Ohio) manages their herd.

IMO, there is one major factor that makes some hunters believers that the ratio is bad.......set-ups......set-ups......set-ups!!!

Before I explain, let me just say that in no way do I consider myself a better hunter than anyone. Also, I do not consider myself to be a good hunter or an expert. I am just brining up a major factor that not many take into consideration. Also RT, I am not singling you out, your buddies maybe but not you!!!

With that said......So much and I mean a lot, depends on the hunter(s) and how he(they) hunt. Plain and simple if you are not hunting right or if in a group, the group is not hunting right, an accurate buck to doe ratio will never be achieved and what you assume is a poor ratio, is in fact a ratio that is good or not bad. In order to achieve an accurate buck to doe ratio, hunters have to think and hunt the exact same way a mature buck lives his life. In lehmans terms, you cannot always hunt where the deer are at.....sounds crazy but let me explain. I am a believer in the less deer that you see, the more accurately you can judge your ratio. Since I started believing in that, the qualities of my hunts have increased dramatically.

A lot of hunters hang a lot of treestand set-ups based on quanity, number of deer seen per sit. They want to go out and see deer, if not everytime to the stand then almost everytime. Now, put 2 and 2 together on that one, those types of set-ups are going to produce far more doe sightings than buck sightings. At the exact same time, these set-ups more often than not when they produce buck sightings, produce sightings of younger/immature bucks. These hunters think that a successful night in the tree can only be achieved if they see better than 5 deer and if they only see 1 or none, the hunt was a waste. Also, this hunter rarely takes into consideration that he might be seeing a lot of deer but a lot of the deer he is seeing, for the most part are the exact same deer night-after-night(especially the does) but he likely believes atleast half of them are different deer every night. So, with most the deer he is seeing likely being does, he easily assumes the ratio is ridiculous.

Now, with the right set-up, a set-up that is geared more towards quality(thinking and hunting like a mature buck lives) and you have a hunter(s) whose prediction of the ratio vastly differs from "the other guys". These hunters may not be seeing loads of deer every trip to the stand but they are seeing enough deer and a lot of the deer they are likely seeing are not all the same deer. This hunter is gonna see some bucks and a lot of them will likely be better quality bucks than the other guy is used to seeing. I'll use my rut hunting last year as an example for this one. I talked to a lot of guys last year that said they just weren't seeing bucks and that their does far outnumbered there bucks. I never once saw it that way. Over a 3 day period last year(Nov. 14-16), I seen a total of 26 bucks in those 3 days. 16 of those bucks were different ones and in those 3 days, I seen a grand total of 1 doe the entire time.....does that sound screwed up to you!?!? That is basically how my entire rut and for the most part my season happened.

I rarely set-up for quanity unless I am just after does, almost all of my set-ups the entire season, including the rut will be set-up for quality more than quanity. With the exception of acorns in the woods, it is an extreme rarity to see me hunt Ag fields or hayfields or any food at all, it doesn't do me any good to hunt these places and do my part to accurately judge my herd. I like places where I see less deer, these places are more likely to produce sightings of different deer when sightings occur. Yes, over food you can get a decent figure on your ratio but you have no idea exactly how many deer are using the plot that you don't see. You might see 5 bucks and 40 does on your food plot almost every night but that doesn't mean that there is not 10 more bucks that use it and you never see.

Buck to doe ratio is always gonna be area specific and management specific but for most areas(I'll even go as high as 90% of the state of Ohio) and given Ohio's management plan, the ratio is not as bad as people think that it is. As the study shows, even if the numbers are off a little, they are still very realistic and its just not possible for it to ever reach a point to be considered bad. Thats not to say that there are not pockets(small pockets) throughout the state where the ratio is out of whack but those pockets are just that.....pockets!!!