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

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

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.

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.

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).