Dr. Randy DeYoung’s article in the October 2005 issue of Quality Whitetails explained this concept and documented through research that breeding is done by bucks of all age classes, irrespective of the herd’s age structure. Yearlings and 2½-year-olds even get in on the action on the King Ranch in Texas, where more than 50 percent of the bucks are 3½ years of age or older. Randy’s research also showed bucks that successfully breed do not sire many fawns. The most prolific buck in their studies only sired six fawns in a single year, and on one study site successful bucks averaged less than three fawns per year over an 11-year period. Anna Bess Sorin found similar results in a Michigan deer herd where 17 bucks sired 67 fawns for an average of 3.9 fawns per buck. Individual bucks sired anywhere from one to nine fawns in her study.

Dominant bucks don’t monopolize the breeding, and they don’t even sire all of the fawns from each doe they breed. Black bear biologists have known for years that a litter of cubs could easily have more than one father, but multiple paternity in whitetails is relatively new information. Randy and his colleagues were the first to report on this. Their study of captive deer revealed multiple paternity occurred in about 24 percent of compound litters. Approximately one in four sets of twins or triplets had two fathers! This means does are breeding with multiple bucks, which further clarifies that individual whitetail bucks do not monopolize breeding.

You're 100% wrong, and once again it goes back to you cutting down ARs every chance you get, even when they have nothing to do with the conversation at hand. I went to a 2hr Kroll seminar this summer in which he specifically talked about the once a spike always a spike montra. They found that these "inferior" bucks ALWAYS caught up in antler growth by maturity (4.5).

Even if what you said was true, it would not explain why this buck lost a point at maturity, and peaked at 4.5, when his subordinate counterpart added points from 3-4, and added inches from 4-5. So again I ask, do you have a plausible explanation as to why this happened.

Adult Sex Ratios

By: Kip Adams

Hunters often ask about the sex ratio of the deer herd where they hunt and then compare that ratio to herds in other areas or states. There are a lot of misunderstandings regarding sex ratios and this article will help clarify some misconceptions. First, what is a sex ratio, what animals are used to determine it and when is it measured? The sex ratio is a number describing the number of adult females for each adult male in a population. The number includes deer 1.5 years and older (all deer except fawns) and describes the population immediately preceding the hunting season. When comparing ratios, make sure you are referring to pre-hunt adult sex ratios. These are the ratios biologists most often refer to, and they should not be confused with observed or post-hunt ratios as the latter are nearly always heavily skewed towards females.

I often hear hunters, outdoor writers, and even biologists refer to 10:1 or 15:1 doe:buck ratios. These cannot be pre-hunt adult ratios because as long as the deer herd is reproducing and recruiting fawns, the ratio cannot become more skewed than about 5 does per buck. The biological maximum is about 5:1 because even in the absence of female harvest, 15-20% of adult females in the population will die each year from old age, vehicles, disease, predators, etc. Also, about 50% of fawns born each year are male, thus the sex ratio gets an annual correction when fawns are recruited. This concept is easier to understand with an example.

Let’s say a hypothetical population contains 120 adult deer (fawns not included).
Pre-hunt population = 100 does and 20 bucks (this is a 5:1 ratio)
During the hunting season let’s say hunters kill 90% (18) of the bucks and 0% (0) of the does.
Hunting mortality 0 does and 18 bucks
Post-hunt population = 100 does and 2 bucks (50:1, heavily skewed after the hunt)
Natural mortality gets added next. Since there are very few bucks left in the population, very few will die from other causes. We’ll say 1 of the 2 remaining bucks dies. However, 15-20% of the does will die from natural causes. We’ll be conservative and use 15% (15 does).
Natural mortality 15 does and 1 buck
Remaining population = 85 does and 1 buck (85:1, the ratio is still heavily skewed)
For simplicity, we’ll say each doe recruits one fawn. This isn’t the number of fawns born but the number that survive to about six months of age. It’s important to realize this is a liberal recruitment rate as the national average is slightly less than one fawn per doe. The most reproductive herds in the country only recruit about 1.2 fawns per doe. For our example there will be 85 (about 43 buck and 42 doe) fawns. These won’t be added to the adult population until the following year but last year’s fawns get added this year. For simplicity, we’ll assume last year’s population had the same number of fawns and immigration and emigration are equal.
Recruitment 42 does and 43 bucks
Pre-hunt population = 127 does and 44 bucks (this is a 3:1 ratio)
This example is simplified but it demonstrates that pre-hunt adult sex ratios can’t become as skewed as many think. However, from a biological perspective, a 3:1 ratio is heavily skewed and reflects poor management on the deer population. This 3:1 ratio could lead to hunters observing 10 or more antlerless deer (females and fawns) per buck.