Presentation on theme: "Joe Hamilton QDMA Aging White-tailed Deer by Tooth Eruption and Wear."— Presentation transcript:
Joe Hamilton QDMA 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 cant compare them
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) Premolars Molars P1 P3 P2 M1 M2 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 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
Separating Deer Into Three Age Classes Yearling Adult Fawn P1 P2 P3 M1 P1 P2 P3 M1 P1 P2 P3 M1 M3 M2 M3
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 3 rd 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)? Yes No
2 ½ years old Keys – six teeth, permanent 3 rd 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. M1 M2 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. M1 M2 Yes M3 Yes
7 ½ + years old 9 ½ + years old?
Next time you harvest a deer, give aging a try!