A really old buck looks old, like this one in the picture.
His body is thick and blocky. Mature deer, say 5½ years and older, are just heavy. Their chests are very deep.
When not alarmed, he moves slowly and with purpose, like he owns the joint.
When you are aging a buck before the rut has occurred, look at stomach girth, provided you get a good, broadside view of the animal. “The older a buck gets, the bigger his belly gets,” notes whitetail biologist Mickey Hellickson. “If the bottom line of the stomach sags noticeably lower than the bottom line of the brisket, the buck is likely mature.”
This characteristic does not work well after the peak of rut, however, because bucks can lose 25 to 30 percent of their body weight during the breeding season. After rut, Hellickson prefers to look closely at how darkly stained a buck’s tarsal glands are. As a buck matures, his tarsal glands appear darker. Use your binoculars.
Another helpful feature is the juncture between the neck and chest. As a buck ages, this area becomes broader, and his brisket becomes more obvious.
Antler-wise, “I advise hunters that overall rack frame and size are first characteristics to look at,” Hellickson says. “I will never use only antler size, though. You have to look at additional characteristics to verify your initial impression.”
Hellickson says to look at a rack’s overall mass, circumference at the bases and the presence of abnormal or atypical points. Non-typical or abnormal points are usually found on older bucks.