“Aging on the hoof”: fact or fantasy?
Kenneth L. Gee – Samuel Roberts Noble Foundation; John H. Holman – Fresh Tracts

Abstract: Use of physical characteristics to estimate age of white-tailed deer (Odocoileus virginianus) in the field, commonly referred to as “aging on the hoof” (AOTH), is becoming increasingly popular as part of selective harvest management programs. There have been no scientific evaluations of this aging method to date. To determine practitioners’ levels of accuracy and proficiency applying the AOTH method, we developed an assessment consisting of a series of photographs of 70 wild, known-age deer from south-central Oklahoma ranging in age from 1.5 - >10.5 years. A preassessment questionnaire was developed to determine participants’ professional status, degree of use of technique, perceptions about the technique, etc. The pre-assessment questionnaire and the assessment were distributed to 2009 Southeast Deer Study Group registrants and other selected individuals. One hundred twenty-nine individuals completed the assessment, consisting of 107 professionals that use the technique, 16 professionals that had little experience with the technique, and 6 non-professionals. Considering only professionals that use the technique, the average percentage of correct age estimates was 36%, with a range of 16-56%. Percentages of estimates correct by age-class for professionals that use the technique were 62%, 43%, 25%, 30%, 25%,15%, 7%, 7%, 7%, and 2% for the 1.5, 2.5, 3.5, 4,5, 5.5, 6.5, 7.5, 8.5, 9.5, and 10.5 year-classes, respectively. Additional analyses emphasizing various age groupings and management and research
implications will be discussed.
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Effects of selective harvest on antler size in white-tailed deer: a modeling approach.
Stephen L. Webb – Hayden Wing Associates; Stephen Demarais and Bronson Strickland – Department of Wildlife and Fisheries, Mississippi State University; Randy W. DeYoung – Caesar Kleberg Wildlife Research Institute, Texas A&M – Kingsville; Brian Kinghorn – School of Environmental and Rural Science, University of New England; Kenneth L. Gee – Samuel Roberts Noble Foundation

Abstract: Selective harvesting in wild deer (Odocoileus spp.) populations is commonly practiced to increase antler size. However, response in free-ranging populations is difficult to quantify because antler response is influenced by environmental variation, population demographics, and harvest intensity. We used quantitative genetics models to determine how white-tailed deer (O. virginianus) antlers responded to selection and what variables (i.e., population size, age structure, mating ratio and heritability) were most influential in improving antler size. We validated genetics models by comparing modeled results with empirical data from a controlled deer breeding program; modeled antler points (AP) and Boone and Crockett score increased (2.2-4.3 AP and 19.1-38.5 in, respectively) after 8 years of selection, similar to observed increases in AP (3.2) and score (36.3 in) from a captive reference population. In modeled free-ranging populations, mating ratio, age structure and heritability were more important in influencing antler response than size of the population. However, response to selection in free-ranging populations was much less (0.1-0.9 AP) than breeding operations even after 20 years of selection. Our models demonstrate how selective harvesting of male white-tailed deer is an inefficient process for modifying population-level genetic characteristics related to antler size. Response of antlers in free-ranging deer will be lower because individual reproductive success is lower, breeding is done by a large group of males, dispersal maintains gene flow from populations with disparate management goals, and reproductive and survival rates are lower.
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A case study of an antler harvest restriction on a public hunting area.
David Synatzske, Morgan Richardson, and Daniel Walker – Texas Parks & Wildlife Department

Abstract: The Chaparral WMA is a 15,000 acre research and demonstration area located in LaSalle and Dimmit counties in the heart of the South Texas brush country. Deer hunting on the area is by lottery permit drawing. The area has an abundance of mature bucks is noted for quality of its buck harvest. The area receives more than three times as many applications for either sex hunts than any other public hunting area in Texas. From 1991 to 1994, hunters were allowed to harvest one buck. Under these harvest regime hunters most often selected mature bucks exhibiting superior antler development or high grading of the deer herd. Regulations were modified in 1995 to increase the harvest of bucks with poor antler development. The bag limit was increased to two bucks and a buck harvest antler restriction was put in place. One of the two bucks must have less than 8-points and the other buck must have inside spread greater than ear width. Our objective was to increase the harvest of bucks exhibiting poor antler development: yearling spikes, and medium age and mature bucks with less than 7 antler points. Hunters were given a pre-hunt briefing explaining the objectives and the rationale behind the antler restriction. Hunters were encouraged to harvest spikes and mature bucks with less than 8 points. Under antler restrictions the harvest of bucks with poor antler development increased from less than 20% of the annual buck harvest to about 50%. A modest decrease (35% to 25%) in the percentage of % mature bucks in the herd has been observed as result of the increased harvest of spikes and other young cull bucks. The number of trophy bucks (> 140 Gross Boone & Crocket) harvested each year has remained stable. A trend of decreasing inside spread in mature bucks has been observed while average gross Boone & Crocket score for mature bucks has remained stable since the implementation of antler restrictions.
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Bryan,

In the AOTH study, the bucks weren't aged using the Severinghaus method. They were captured and tagged at birth so they were truly "known age".

On a side note...It's so good to see folks critically thinking about these studies and how they are designed and not blindly accepting them at face value simply because they are published. Unfortunately most folks see it in print and accept it as gospel. There were a number of studies presented that had me shaking my head.

Bryan,

You have an e-mail.

Comcast...does your att.net have the same prefix?