White-tailed Deer
Spikes Are Not Inferior, or Are They?
John D. Williams, Ph.D.
Associate Professor Veterinary Medicine, Texas A&M University
Reproduced from The Journal of the Texas Trophy Hunters, July/August 1994.
No, they are not inferior as animals. They may be undesirable as breeders, but inferior, no. So let's stop using the word inferior and superior, they may be desirable or undesirable as breeders and only then if the trait you wish to change is genetically controlled, i.e. coat color, body weight, antler points, etc. If white calves are desired, one would not use an Angus bull, but that doesn't make him an inferior animal. Because coat color is inherited (genetically controlled), the Angus is undesirable as a herd sire, but inferior as an individual, no.
In 1960, Dr. W.B. Davis believed "the male fawn produces a spike set of antlers its first year," but if he were living today, he would have reviewed the literature and probably revised his book accordingly. He probably would say, "Most spike-antlered deer are yearlings, but not all yearlings produce spike antlers." It is unfortunate his students cannot or will not do the same. Their minds seem to be as concrete "all mixed up and firmly set."
This article is in response to the articles by Don Haley and S.W. Stedman in Texas Trophy Hunters, P.T. Brown in North American Whitetail, and John Wootters in Petersen's Hunting. It is also intended to be an introduction to the genetic research at the Kerr Wildlife Management Area, Hunt, Texas.
The views presented in this article are the views of the author and should not be assumed to be those of the TexasParks and Wildlife Department.
I have no strong feelings one way or another concerning harvesting or protecting spikes and/or does, trophy management, deer hunting, or high fences. I have a background in population genetics and statistics and wish to present some data collected from a specific experiment conducted at the Kerr Wildlife Management Area.
In the article by Haley, Steve Nelle was quoting data from the Kerr Wildlife Management Area (KWMA). The data, which was said to present the "naked truth", came from the final report of a five-year pilot study dated May 26, 1987, which used only five animals in each of two groups. This study consisted of only 10 yearling deer, which were classified as spike or fork (1) according to the sire (2). The five deer in the spike group came from one spike sire which was mated to four different females, one which had no pedigree and three which were sired by spike sires. The five deer in the fork group came from a single-forked sire which was mated to only three different females. This is not a line of deer and certainly not a population. It would not be considered an adequate sample from which to make broad statements concerning fork vs spikes; it is, however, large enough to suggest trends and provide support for further investigation.
Several quotes from the report are presented and the data and figures which were available to Mr. Nelle are presented in Tables 1-6 and Figures 1-6. Although the tables have been expanded, the original data from the study are included and was used to determine the actual and percent differences between the two groups of deer.
There are a few words in the report, and in the following quotes which I feel should be changed. Five progeny from a single sire do not make a line and five progeny do not make a population. They are a sample which was used to estimate a population mean and as pointed out in the quotes, a very small sample. They do however indicate a trend and as pointed out in the report should be studied further with a larger sample. The words superior and inferior should not be used.
Selected Quotes From the TPWD Report
Abstract: "At 1.5, 2.5, 3.5 and 4.5 years of age, the means for antler weight, main beam spread, main beam length, basal circumference, and number of points of the offspring of the fork-antlered sire line were greater than those of the offspring from the spike-antlered line. However, when analyzed using analysis of variance procedure with one degree of freedom, the population means were not statistically different. This was due to a small sample size."
Procedures: "In January, 1983, five buck fawns sired by a fork-antlered yearling buck and five buck fawns sired by a spike-antlered yearling sire were permanently marked by freeze branding, ear tagged, and released into a 96-acre experimental pasture at approximately six months of age. Each year, in October, all bucks were captured, weighed, and antler measurements obtained. Antler measurements included main beam spread, main beam length, basal circumference, number of points, and antler weight."
Trend analysis: "Antler development and body weights between the two populations of deer based on the sire line from 1.5 to 4.5 years of age are shown in Figures 1-6. Although there is no statistical difference between the means of the two populations of deer by sire line, there is a definite separation in trends of the two population means for all parameter measurements, with the fork-antlered sire line always being superior to the spike-antlered sire line."
Conclusions: "When data was analyzed by sire blood lines, there was no statistical difference between the two population means at 4.5 years of age. However, trends in the means indicated that the two populations did remain separate. This would indicate that the sample size used in the two populations was not adequate. The trends in the differences in the two populations are much the same as the population trends in the "Antler Formation in White-tailed Deer Study" which had a much larger sample size and which had statistically different populations based on antler development and body weight."
Recommendations: "Another study should be considered in the future with another group of deer in order to increase sample size and remove the influence of individual deer performance. Data should be analyzed by number of points as yearlings rather than by sire line."
End Quotes
The report also pointed out that there were two deer which were exceptions to the trend and it was those two deer which Mr. Nelle chose as the basis for his "naked truth" statement. There was one in the fork group which was a 3-point yearling and produced the second smallest set of antlers at 4.5 years of age based on antler weight and a 4-point yearling from the spike line which as a yearling had more points and antler mass" than two of the yearlings in the fork group. These two deer are actually very important, because they led to the recommendation that "data should be analyzed by number of points as yearlings rather than by sire line." This conclusion was proven correct at the conclusion of the heritability portion of this study, which has been published in Heredity, a scientific journal. That portion of the study concluded that heritability for antler traits was high, and therefore, individual selection would be more effective than family or line selection.
The tables show the difference between the average for the spike and fork groups for 4 years and also the percent difference. In all cases, the fork group is greater than the spike group, and ranges from 6.7%-15.2% advantage for main beam spread; 13.1%-54.4% for main beam length; 13.5%-22.4% for basal circumference; 12.9%-108.3% for total points; 31.3%-125.6% for total antler weight; and 10.2%-15.3% for live body weight. It is difficult to understand how this data can be interpreted to prove that there is no difference between spike and fork-sired deer on the one hand and to state that only 20% of the spikes are inferior and 80% "will likely develop into decent bucks if allowed to grow to maturity." If you will review the tables carefully, they will reveal that in almost all cases, the fork group was equal or better at 3.5 years than the spike group at 4.5 years.
In future issues of this Journal, I plan to report results and success genetics, heritability and research findings from a genetic experiment, conducted at the Kerr Wildlife Management Area (KWMA), which spans 20 years and has adequate numbers to give a better feel for the inheritance of antler characteristics and body weight in white-tailed deer. The KWMA has the largest pedigreed whitetail deer herd in the world and the combined data from this herd includes records on more than 1,600 deer and 1,103 sets of antlers from 384 different deer. Thirty of which have data for 6 sets and 90 which have data for 4 sets of antlers. Of these 90 deer, 30 were spikes at 1.5 years and the rest were forks.
The "magical ingredient" referred to by Nelle is not magical at all, but a long known genetic fact - like begets like. It was not the fault of the Kerr study that hunters, managers, and landowners used the information incorrectly. Even the least knowledgeable rancher knows he cannot produce a herd of show cattle while rearing them on the rocks of the hill country. He also know he can't take a herd of grade cattle and produce show stock simply by feed alone. Stedman apparently knows nothing about gene frequency, random breeding, genetic equilibrium or selection and accuses "Mother Nature's" bell-shaped curve and its magic of all the things he cannot explain by nutrition and age. He also describes the distribution of B & C scores as a "statistical phenomenon."
There are Cow/Calf, Purebred and Showstock cattle operators and these same types of management styles may be found in deer operations. The cow/calf is similar to a deer manager who wants to provide many deer of any quality for his hunters, the purebred manager may produce fewer deer of a better average quality for his hunters and the showstock manager strives to produce trophy class deer, but for fewer hunters. These managers would obviously have different objectives, herd densities, culling levels, etc. and it makes no more sense to have only one management style for all deer than it would to have only one for all cattle.
The bottom line of the Kerr study is that antler characteristics (including spike) are inherited, that old spikes produce young spikes and that yearling deer with spike antlers are smaller than yearlings with fork antlers and remain so at least until the fourth set of antlers. This is a very important finding for the manager who wishes to move into the "purebred" or "showstock" class. It is of no value to the cow-calf operator. It doesn't matter if you harvest all or none of the spike bucks any more than if you use a purebred or scrub bull. All females will produce offspring, only the quality will differ.
Readers of this magazine are probably not interested in the cow calf type operations, but in purebred or probably showstock operations. There is no other herd of deer like the Kerr deer herd and no other published genetic research available. There are some deer breeders, but no geneticist actively involved in long term whitetail deer genetic research. This type research requires many years and hundreds of animals. The KWMA herd is a very valuable herd and one which everyone interested in whitetail deer should be aware of and actively involved in assuring its continued existence.
If anyone is interested in a concentrated dose of genetics and statistics and a summary of research at the KWMA and will so indicate to the editor, he will forward the names and addresses to me and I will schedule and present an all day seminar at the Kerr Wildlife Management Area. I would also invite each reader to visit the KWMA, see the facility and listen to the presentation by Bill Armstrong.
Are Antler Characteristics Inherited?
Part 2 of Spikes Are Not Inferior - Or, Are They?
John D. Williams, Ph.D.
Associate Professor Veterinary Medicine, Texas A&M University
Reproduced from The Journal of the Texas Trophy Hunters, September/October 1994.
If so, then the antler characteristics within a deer herd can be changed through selection. If not, then selection will be of no value. Data will be presented which supports the belief that antler characteristics are indeed inherited (genetically controlled) and that selection can change the characteristics of a deer herd. Each time a deer is removed from the herd (death, harvest or migration), there is selection because those remaining become the parents of the next generation. Remove the undesirable and the herd will improve. Remove the desirable and the herd quality will decrease.
If whitetail deer antler characteristics are genetically controlled, then it is possible to manage a deer herd in such a way as to change the average antler quality of the herd without waiting 10,000 years for Mother Nature to make a change.
Data collected at the Kerr Wildlife Management Area and published in a scientific journal (July 1994, Heredity) indicate that antler characteristics are inherited and the heritability estimates from this article are shown in Table 1. Although the heritability of a trait is constantly changing due to gene frequency changes caused by natural (death, migration) and artificial (harvest) selection, these estimates give a good indication of the magnitude of the influence of genetics. Heritability may be defined as "An estimation of the degree by which a characteristic is controlled by heredity as compared to the influence of the environment and other factors." It is the percent of the total variability of a characteristic (antler weight) which can be attributed to heredity (genetics). The heritability estimate for antler weight shown in Table 1 suggests that 75 percent of the variability in antler weights (mass) may be attributed to heredity.
I have no strong feelings one way or another concerning harvesting or protecting spikes and/or does, trophy management, deer hunting or high fences. I have a background in population genetics and statistics and wish to present more data collected from research conducted at the Kerr Wildlife Management Area. The views presented in this article are the views of the author and should not be assumed to be those of the TexasParks and Wildlife Department.
In the 1991 Sept/Oct issue Newsletter of the Texas Section of the Society for Range Management, Steve Nelle reported that Dr. Harry Jacobson "summarized findings from 15 years of records from a 150-head captive deer herd" as follows:
- Looking at antler points of yearling bucks provided no correlation to antler development later in life.
- Spike-antlered yearlings were just as likely to produce large antlers later in life as 6- to 8-point yearlings.
- The prevalence of spike-antlered yearlings was correlated to birth date. No June-born bucks produced spike antlers, while 38 percent of September-born bucks produced spike antlers.
- Overall, the captive herd only produced spikes on 20 percent of yearling bucks, while adjacent private-land produced spikes on 60 percent of yearling bucks, the only difference being nutrition.
- The best two sets of antlers produced over the 15 years (168 and 195 B & C points) were both 3-point bucks as yearlings.
- You can do little or nothing to improve antler genetics except to leave obviously superior bucks in the herd.
Although I accept Dr. Jacobson's results, no supporting data was presented and the statements conflict with results from 20 years of genetic research at the Kerr Wildlife Management Area and results from a study in Louisiana which was reported at the Southeastern Association meeting in 1992. Data reported in 1989 (Effects of Genetics and Nutrition,Texas Parks & Wildlife Department) show a correlation between first and third set of antlers for 64 deer to range between 0.60 for main beam spread to 0.83 for total antler weight.
Data reported in this article (Tables 2 and 3, and Figure 1) are from 104 deer for which 1.5, 2.5, 3.5, and 4.5 year old deer, we are comparing 104 yearlings to these same 104 deer as 4.5 year-old deer. I realize Tables 2 and 3 are difficult to read, but they help answer the question, "What will a yearling buck be at 4.5 years of age?" Table 2 contains information about total antler points as yearlings and total antler mass (weight) at 4.5 years. In Table 2 there are 30 yearlings which had 2 points and 10 (33 percent) of these had 8 points at 4.5. There were 11 yearlings with 8 points and only 2 (18 percent) had 8 points at 4.5 , but 8 (80 percent) had 10 or more points at 4.5. No yearling with 2 points attained 10 or more points at 4.5. There were 31 deer with 10 or more points at 4.5 and 23 (74 percent) of these had 6 or more points as yearlings and 8 (26 percent) had 3, 4, or 5 points as yearlings. No 10-point 4.5 year old deer was a spike as a yearling. Table 3 shows the total antler weight at 4.5 years for these same 104 deer. The 30 yearlings with 2 points all had antler weights less than 1,000 grams while 10 of the 11 yearlings with 8 points had antler weights greater than 1,000 grams while no deer with 2 points as yearlings had antler weights greater than 1,000 grams.