Counting growth rings with a spotter

[Travis2282]

I was checking out my new spotter today for clarity out to various distances and was just wondering at what range do most guys need to get to to be able to count growth rings on sheep?

 

[Blockcaver]

Lots of variables to make any definitive statements. A few in no particular order are light conditions, heat waves, fog or mist, tripod and scope stability, wind, whether you are looking into the sun or if it is at your back. Your position affects how steady you are too.

Some sheep are really tough to age due to false growth rings. Biologists have argued in BC court over the age of a ram. Old rams get really tightly packed growth rings past year 8. Maybe even hiding one in the hair, but you are never sure. A broomed off thin-horn is tricky too as you they grow less horn the first year or two versus a bighorn.

So with all those caveats, I can generally age a ram to within one year at 200-300 yards with a Swaro 20-60 x 65 HD scope assuming he is between 4 and 8. Tougher on the 9-13 year olds. Wet horns show rings better than dry. Some rams have very dark and vivid rings, others are very subtle.

A series of phone scope pictures that can be enlarged really facilitates aging and may allow aging way out there given a good photo.

 

[Bruce Culberson]

Blockcarver hit the nail on the head. I only run a Bash & Lomb Elite 15-45x60 and generally had to be 200-300 yards to age sheep. One time in a light misting rain I could age an 8 yr old ram at 600 yards - the annuli appeared to have been drawn on with a sharpie. Another time on a ram at only 100 yards I could not get an age. That ram had really light amber coloured horns and the rings were not distinct at all.

 

[Travis2282]

You are much closer than I would have thought!

 

[wantj43]

For general information might be a good exercise to age sheep with a spotting scope. To use that information to harvest an animal based on age is not. A person's ability to age sheep with a spotting scope certainly could be tested by setting up some horns at two or three hundred yards, aging then comparing the results with actual age.
There is so much variation between horn growth patterns of individual sheep that it seems determining age accurately would be difficult to say the least.
Good luck
Joe