IMO this is the million dollar question and one that baffles me. We do our best to let these three year old bucks go and have done so for 10 years on our farm. We have several of them around and frequently get pictures of them. But we almost never see or get pictures of these deer the next year and I have no earthly idea what happens to them or where they go when they are four years old. Assuming half of them do not survive whether through getting shot during hunting season or through natural causes we should still have several four year olds running around. It is as if they almost all vanish never to be seen again. Hunting pressure in our area is moderate. I wish someone could give me a good answer for this question!
Ha! You're in Virginia Hoseman? Yes, if I remember correctly. The odds of a buck making it to 4 1/2 are really slim even if you do pass on a 3 1/2 year old. Fantastic trigger control is just one of so many things can happen. The neighbors aren't near as good. Disease. Car crashes. Poaching. Crop Damage Control. Dogs in Virginia making them hide even more successfully.
Let's play a numbers game. You won't like mine (I think they are reasonable averages), so use your own.
Assume we have a square mile, 640 acres. It's reasonable to assume at the beginning of the season there are 40 deer frequenting our square of America. We will go with a one-to-one ratio for anything else turns out even worse.
Of the 40 deer, 10 are fawns, 15 are does, and 15 are bucks. Without getting into the details, your buck herd age structure is probably:
35% - 45% 1 1/2 year old's, (6)
30% - 40% 2 1/2 year old's, (5)
15% - 20% 3 1/2 year old's (2)
5% - 15% 4 1/2 year old's. (2)
Let's kill half of them. That's 7 bucks harvested per square mile, not an unreasonable number a little on the high side here in VA.
Now you have 3, 3, 1 ,1 heading into the next year. There's still a whopper 5 1/2 year old out there and another 1 or 2 that might be living 4 1/2 year old's next year. In a square mile. . Just imagine taking away all the bucks except the 3 1/2 and 4 1/2 year old's. It would be like hunting public land in mature forest.
Use your own numbers, but I think it's just the nature of things that very few whitetail bucks around here make it to the 4 1/2 stage.
How can you make it better? Fence? Just kidding sorta'. How do you control age structure? Well, yes, let 'em walk, but your neighbors say let's kill 'em all. And then there are all the other hazards mentioned above. It just ain't easy being a deer.
Darn neighbors. Disease. Car crashes. Poaching. Crop Damage Control. Dogs in Virginia....