Joe HamiltonQDMA

Aging White-tailed Deer by Tooth Eruption and Wear

Why Age Deer?

• To allow comparisons within sex and age classes

• To determine appropriate harvest strategies

• To track progress of management efforts

Both of these bucks are 8-pointers, but without knowing their age, you can’t compare them

Jawbone Removal

Anatomy of a Jawbone

Back

Buccal Crests (cheek side)

Front

Lingual Crests (tongue side) Incisors

Back Cusp

Anatomy of a Jawbone

Dentine(dark)

Enamel(white)

PremolarsMolars

P1P3

P2M1M2

M3

Tooth Eruption and Wear Technique

Based on two processes:

1. Tooth eruption is the process of gaining additional teeth over time and replacing temporary teeth with permanent ones.

2. Tooth Wear – is the process of tooth erosion over time with age.

Tooth Eruption

Whitetails are born with three temporary teeth (premolars). From this age until they are about 18-20 months old, they replace these temporary teeth with permanent teeth and also gain three additional permanent molars. All whitetails 18 months of age or older should have six permanent teeth on each side of their lower jaw.

Tooth Wear

1 ½

3 ½

5 ½

Dentine (dark)

Enamel (white)

Tooth Eruption and Wear Technique

Advantages

• Requires no specialized equipment, costs nothing, and can be done at camp

• Can be learned by most deer hunters and managers with sufficient practice

Disadvantages

• More subjective and highly dependant upon ability of individual ager

• Believed to be somewhat affected by soil and habitat quality

Aging – Step 1

Separate Into Three Age Classes

1. Fawn (6 months)- three or four total jaw teeth

2. Yearling (1 ½ years old)- six teeth, but temporary third premolar (P3)

3. Adult (2 ½ years old) -six teeth, but all permanent

Temporary premolar (three crests)

Permanent premolar (one crest)

Temporary vs. Permanent Premolars

Separating Deer Into Three Age Classes

Yearling

Adult

FawnP1P2P3M1

P1P2P3M1

P1P2P3M1

M3M2

M2M3

Fawn (6 months old)

Key – Only 3 or 4 fully erupted teeth

Yearling (1 ½ years old)

Generally fully erupted

Note permanent tooth erupting, may already have replaced temporary tooth if harvested late in season

Keys – 6 teeth and temporary 3rd premolar

Aging – Step 2

Estimating Age of Adults Based on Wear

This technique is based on the width of the dentine on the molars compared to the width of the surrounding enamel.

Question - Is the dentine (dark) on the lingual crests approximately twice as wide or wider than one strip of surrounding enamel (white)?

YesNo

2 ½ years old

Keys – six teeth, permanent 3rd premolar (P3) and dentine not twice as wide as surrounding enamel on the first molar (M1)

M1

No

P3

3 ½ years old

Keys – The dentine is twice as wide as the surrounding enamel on first molar (M1) but not the second molar (M2). The back cusp is starting to show noticeable wear.

M1M2

Yes No

4 ½ years old

Keys – The dentine is twice as wide as the surrounding enamel on the first and second molars (M1 & M2) but not the third (M3). The back cusp is also starting to form a “cup.”

M1M2

Yes Yes No

M3

5 ½ - 6 ½ years old

Keys – The dentine is twice as wide as the surrounding enamel on the first, second and third molars (M1, M2 & M3). The back cusp is heavily cupped and slanting.

M1M2

Yes Yes

M3

Yes

7 ½ + years old

9 ½ + years old?

Next time you harvest a deer, give aging a try!