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Discussion Starter · #1 ·
I thank all of you for your interest and encouragements to pursue the "dialogue" : as I have presently the time to do it, I decided to open a new fundamental topic : average and individual "quality", which should be better looked at in terms of physical condition which governs many thing including antlers weight (which depends on body weight) and early oestrus.

The physical condition is energy budget dependent, it will only be good if the input is greater than the output.
INPUT :It varies according to many different parameters (habitat, meteorological conditions, deer), most of which can be highly variable with time, and even from year to year, even in the SAME northern or southern area :
The forest evolves, as the trees grow,less sun will reach the soil, the understory quality lowers, shelters can become more scarce.
The onset , and "quality" of spring and winter time can vary a lot anywhere :
- in red deer, the average weight of calves, at birth, will vary of almost + or - one Ib for each one degree (C.) of average spring temperature prior to birth,
- As a result it is possible to predict the average birth weight on the basis of the date at which the cuckoo starts singing !!
- September rains are very harmful to the vegetation, they can seriously prevent fat storage, increase winter losses, lead to less births the following year, delay the following year estrus date ... (As one can see, the "Winter Severity Index" is, of course most important, it is not the only weather variable.)
- The population density and stucture : it is evident the density needs to be well below the maximum biological carrying capacity (your 62,5 % seems good to me).
If as in red deer, does, fawns and yearlings tend to be very gregarious and form philopatric groups, it becomes very easy to reach an overpopulation, locally, on does territory.
- Human disturbances in the deer range can also have a great influence : hikers, skiers, photogaphers, mushrooms or cast antlers searchers ... They decrease the really available range, lead to "false" overpopulation or make the real ones more serious, in the quieter areas (they also highly increase the "output" through flights, energy output 7 1/2 times that of lying) : their consequences are most severe in winter (I have unfortunately a good personal experience about this).
- If as in red deer, there is also a pecking order between does, the fawns of dominant does will benefit of better living conditions than the other ones ( both for food and shelter).
- The quality of the "input" differs also even prior to fawns conceptions : not only will a dominant doe in good physical condition come in oestrus early, it will also better nourish the embryos then her fawns.
OUTPUT : no need to develop.

The physical condition can be appreciated from fat reserves : they are stored from inside out, first around nerves, then in the bone marrow (in case of starvation it will look pink and gelatinous in place of fatty and yellow ), then around internal organs (the amount of fat around the kidneys is a good indication), and to end with, subcutaneously (as over the rump).

If we leave wounds or diseases aside :
The average "quality" of a given herd results from the average physical condition, it may varies significantly from one year to the next due to any of the above, especially for rutting males and calves.
The individual "quality", wether of a male or a female, above or below average, is the result of the favourable or unfavourable circomstances met by the individual from prior to birth on, it also can vary from one year to the next, especially for the most vunerable ones, during the crucial period of maximum body growth.
(As any lateness of development occurring during this period is irreversible, these should obviously be the preferred preys.)

Let's suppose a good habitat at the right density, and a dominant female in good physical condition : she will come in oestrus early, will conceive early, will have access to the best forages and shelters. If the following winter is not too rough, if spring comes early, she will gestate in good conditions, will give birth early, will have plenty of good milk.If not too much september rain the newcomers will reach an optimum development prior winter and enter it with plenty of fat reserves (buttons will appear early ?). Another good winter and early spring, the newcomer(s)will become very strong yearling(s), the female will come in estrus early, the male antlers will have as many points as possible for his age, and if they survive, they will both become magnificent dominant animals ...if they are lucky enough to reach full biological (and ethological) maturity.
Reverse all variables and you will get just the opposite result.
To end with, all intermediate "end products" are possible.

This is the way I think, one may explain average diversity between different populations of a same species and individual diversity inside each of them.

Here I have to express my gratitude to all the researchers who opened my mind and eyes to all this through all their writings.
PS : I am just trying to prolong the so useful impact of their work to those who might need it, and I will take advantage of this topic to very strongly advise the reading of two GREAT books whose fundamental basic data can be extrapolated to whitetail:
RED DEER Behavior and Ecology of Two Sexes (TH CLUTTON-BROCK, FE GUINNESS, SD ALBON, The University of Chicago Press, 1982)
RED DEER IN THE HIGHLANDS, TH CLUTTON-BROCK, SD ALBON, (BSP Professional Books, Blackwell Scientific Publications,Ltd.)
Friendly your's,

1,635 Posts
I am not one who has a hunger for reading text books (or most books for that matter) but I have become very interested in the things that Belbriete has written here. I am grateful for the learning in a painless, even fun way. thanks.


266 Posts
Discussion Starter · #5 ·
To Sarge :
Believe me, if you are a passionate deer hunter, you would have much trouble to leave the two books I quoted above, to go to sleep ! They are not "textbooks", they are a wonderful and fascinating trip inside the deer world !
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