>Does the term "mature buck" officially refer to one that is at least 5 years old?
I agree, at about 3.5 y.o. I think it is appropriate to call a Coues a mature animal - there is no rule on this of course, it depends on your personal standards.
>Can a buck be 3 or 4 years old and have a 90-inch rack in Arizona?
Absolutely. Antler size depends on 3 things: Age, Nutrition, and Genetics. If the nutrition and genetic foundation are there a 3.5 year old can sport an impressive rack.
>What is the minimum age that you would expect a buck to have in order to >make B & C at 110 points typical net score?
This would be pretty unusual for a 3.5 year old, but not unheard of for 4.5 or greater. The influence of nutrition and genetics are so important it is impossible to generalize about antler size at various ages.
>At what age do Coues bucks typically start regressing in Arizona?
No one has studied this for Coues. It would require recapturing or re-evaluating the same deer though their life and it hasn't been done to my knowledge. A small sample of AZ Coues data I reviewed indicated deer were regressing in the 6-8 age class (maybe not until 8 years). In eastern WT it has been studied and it seems that at 7 or 8 overall antler size declines. Generally tines get shorter, antlers get thicker. Sometimes individuals will keep getting bigger until 10 years - again, age an genetics are playing a role.
>What is the typical lifespan of a Coues buck in Arizona assuming death by >natural causes? I would expect it to be several years longer than deer in >northern climates.
I don't think there would be much difference between AZ and northern whitetails. Northern WTs have the harsh winters but we have the equally harsh June period that is our nutritional bottleneck. A lot of natural mortality probably happens during this dry summer period if deer don't have the fat reserves to make it through.
-Cervidnut
