Photo of lion outline.
 
Photo of lion teeth up close, text: Mountain lion age and sex I.D. chart.

Cougar Age and Sex Identification Guide


By Cougar Specialist Rich Beausoleil, Washington Department of Fish and Wildlife

Male and female mountain lions appear almost identical and getting a good look at a cat's rear end is often the only way to tell for sure the sex of the animal. Determining the age can also be tricky, but a chart and photos provided by the Washington Department of Fish and Wildlife offer a helpful guide. This feature was adapted from a flier, which is also available here for easy printing.

Age Classification Chart

With normal body condition, most mountain lions should fall within the parameters of this identification chart.

AGE, SEX, AND CLASSIFICATION
Washington Department of Fish and Wildlife
Weight
(pounds)
Male Age Male
Class
Female Age Female
Class
Notes
10 2mo Kitten 2mo Kitten Spots very evident
20 4mo Kitten 4mo Kitten Spots evident
30 5mo Kitten 5mo Kitten Spots somewhat evident (hip area)
40 6mo Kitten 6mo Kitten No spots. Double canine1 (perm is shorter)
50 7mo Kitten 8mo Kitten Double canine1 (~equal length)
60 8mo Kitten 10mo Kitten Perm canine ¾ erupted
70 9mo Kitten 12mo Sub-adult No yellowing on teeth
80 10mo Kitten 14mo Sub-adult No yellowing on teeth
90 11mo Kitten 24mo Sub-adult No yellowing on teeth
100 12mo Sub-adult Over 24mo Adult No yellowing on teeth
110 14mo Sub-adult Over 24mo Adult No yellowing on teeth
120 18mo Sub-adult Over 24mo Adult Light yellowing on teeth
1302 24mo Adult unlikely Light yellowing on teeth
1402 Over 24mo Adult unlikely More yellowing on teeth
(at 4 yrs. yellow is prominent)

1 Double canine references to the deciduous canine and the permanent adult canine being present for a short time.
2 Only males get above 115 pounds.


Determining Sex

Photo of female and male lion rumps to identify sex.

Here are two photos of a cougar's backside. The photo on the left is an 8-month old female and the right side is an adult male. Notice the black spot of hair on the adult male (it surrounds the penis sheath), only males have this black spot (kittens are harder to differentiate but follow a similar pattern).

Also, notice that the anus on both sexes is directly under the tail but how the male has the distinct spacing (3-4 inches) between the anus and the scrotum. The female parts are much closer together.


Determining Age from Teeth

Photo of adult and cub teeth for age comparison

LEFT: An adult female. Notice the yellowing of the teeth and the worn incisors. Also notice the length of her canine compared to the kitten on the right. This cougar's canines are still fairly sharp; they get duller with age.

RIGHT: A 7-month old cougar showing a double canine of equal length; the rear canine is about to fall out.


Photo of adult lion teeth being measured

This close up of the adult female pictured above shows how to measure gum recession. In this case 3mm from gum line to beginning of canine taper.


Photo of adult lion teeth showing distance to measure to get age.

Photo of subadult lion teeth showing no gum recession.

The two examples of gum recession above will help you classify a cougar's age. The first is an adult and the second is a subadult. Notice the gum recession on the adult: from the gum line the tooth is straight before it begins to taper. The sub-adult tooth is tapered throughout (there is no recession until about 1½ years).


Gum Recession Chart

Chart of gum recession and age, millimeters of recession approximately equals age, after two years old.

VIEW PRINTABLE VERSION OF THIS PAGE

courtesy of the Washington Department of Fish and Wildlife


 
Photo of a lion laying on a rock looking at camera.


Mountain Lion Frequently Asked Questions

by Mountain Lion Foundation

Answers to your questions about mountain lions, cougars, pumas, catamounts, and panthers. They are all the same animal! Whatever you call America's Lion... he's more than a trophy... too few in numbers... across far less habitat... in a land with more people....