Hypogonadism in Deer

Stag bucks can result from the condition hypogonadism. Hypogonadism is fairly common in parts of Central Texas. Hypogonadism stag bucks keep antlers in velvet year-round and are sterile.

What is Hypogonadism in Deer?

White-tailed bucks afflicted with hypogonadism are somewhat common in parts of the Texas Hill County.  The majority of these stag bucks come from the “granite gravel” soil. This soil type dominates much of Llano County and Mason County. This type of soil also extends slightly into counties bordering to the north and south.

In normal years, the incidence of stag bucks in the Edwards Plateau region is low, with 5-10 percent of bucks having hypogonadism. During years of increased hypogonadism, incidence in granite gravel areas can rise 50 to 80%. In certain years, some areas reported over 40 percent of bucks killed were stag bucks.

Hypogonadism in Deer Results in Stag Bucks

Hypogonadism in Deer in Central Texas

The cause of hypogonadism in deer is unknown, but research suggests that the condition seems related to post-drought conditions. Researchers believe it must be caused by consumption of some plant containing a gonadotoxin that proliferates in granite gravel soils following drought.

Unfortunately, such a plant was never identified in the Texas Hill Country by researchers. Generally speaking, veterinarians believe that consumption of certain plants associated with the breaking of drought causes increased deer health problems.

For example, Sitka black-tailed deer on Kodiak Island in Alaska exhibit a high rate of hypogonadism, abnormal antler growth, and odd antler shedding. Researchers hypothesize that it may be the result of long-term consumption of plants high in estrogen.

In the granite gravel area of the Edwards Plateau, it is theorized that pregnant females consuming these phytoestrogens pass these substances to male fetuses via placenta causing hypogonadism before birth. Furthermore, it’s suggested that whitetail bucks can contract the condition later in life if their own diet is high in phytoestrogens.

Plants Cause Hypogonadism?

The theory is that bucks be impacted prior to or after birth. If while in the womb,  hypogonadism is caused by plants that pregnant does are consuming during gestation. Two plants in the region can become abnormally high in natural plant estrogens have been mentioned as possible causes of hypogonadism in bucks.

Unfortunately, there is no evidence to support the claim. That said, the two plants identified seem to make sense based on their characteristics. Spikemoss is a low, mat-forming plant related to ferns that grows in granite outcrops. It’s the first plant to “green up” following prolonged drought. As a result, spikemoss may be eaten by gestating does in abnormally high amounts in late-winter and early-spring.

In addition, peavine is an annual weed that is common in wet springs in the granite gravel area of the Hill County. It’s especially prolific following drought when there is a lot of bare ground. It’s been noted by veterinarians that abnormally high levels of selenium in deer diets can cause pen-raised bucks to not shed their antlers. Peavine is known to contain high levels of selenium, so it may contribute to hypogonadism in bucks.

Managing Hypogonadism in Deer

There seems to be no easy answer to hypogonadism when it comes to white-tailed deer management. Though two plants have been hypothesized to cause the condition in deer, it turns out that many plants can be high in estrogen. As a result, there may be no way to manage the habitat or deer population to improve the situation.

It is interesting that hypogonadism is most common in the granite gravel area of Central Texas. There is definitely something in the soil, or so it seems. It is possible that there may be some synergistic effects of plant toxins, compounds, or estrogens combined with high levels of some trace minerals in these soils. The cause remains a mystery, but hypogonadism has an impact on deer management in this area. Stag bucks remain in velvet year-round and are sterile, so they use habitat and provide little in return.

Coyote Control for Managing Deer and Reducing Predation

Question: “We are interested in whitetail deer management. Specifically, we want to use predator (coyote) control to increase the number of deer on our property. We have 278 acres in North Texas. We have worked on improving the habitat over the past 3 years by attempting to increase browse cover and plant diversity. From what you know, does predator/coyote control work to get deer numbers up. We’ve read that coyotes are huge predators of deer fawns. It would stand to reason that removing fawn predators would help overall survival? Thanks.”

Response: Are Predators Really Limiting Deer in Your Area?

If you are looking to protect your deer herd, is the population on of deer in the area low? If it is low, is that due to predators or is there something else you could do to better benefit the existing deer herd? In your case, it sounds like you have started to improve habitat for deer, but can more be done. Is the deer population actually low or do you just want more deer? First, figure out exactly how many deer you have by carrying out surveys for deer in the late summer. Then take a close look at the plants deer use and eat and see if this number can go up or needs to go down.

When it comes to whitetail numbers, in most cases there are better explanations than excessive predators on as to why deer populations are low. In areas where deer abundance is high, predators on is an important tool in population on control. In the absence of all predation, most hunters would be incapable of harvesting enough animals to manage a whitetail deer population on on a landscape level.

Can You Reduce Predators in the Name of Deer Management

A study conducted in 1974 on the King Ranch in Texas compared two areas, one with extensive predator control (steel traps, various poisons, and shooting) and one without any predator control. Both areas consisted of roughly 5,000 acres. The area in which predators were extensively controlled for two years showed an increase of fawn survival by an average of 68% and also a noticeable increase in overall deer abundance. After the study concluded and predator control was not continued, predator populations in the area where they had been controlled returned to the pre-study levels within 6 months (Beasom, 1974). INTENSIVE predator control worked, but the benefits stops as soon as the control ends.

With this study in mind, most landowners would not be able to conduct such extensive predator control methods and also not have the ability to access acreage of that size in this area. Predator control on small acreage may lead to you seeing less predators on that tract, while in reality no significant reduction in predator numbers has been made at the scale needed to significantly increase the survival of fawns, chicks, or poults. Coyotes can range several miles. It would take intensive coyote control to remove every predator that crosses your property. And you would have to be diligent about continuing to reduce the coyote population for years to come.

Controlling Coyotes is Only the Start

On the vast majority of properties coyotes are not the limiting factor. Research and our instincts tells us that less predators means higher deer survival, especially when it comes to fawns. It’s important to realize that more and more deer are only good up to a point, then they will begin having a negative impact on the habitat, which will in turn cause reproduction to decrease.

Predator control can have a place in a deer hunting and management program, but it should only be a component of a holistic approach. Focus on increasing food, cover, water and usable space and the habitat found on your property as well as the deer that live there will benefit.

Grow Bigger Bucks: Cull Bucks With Missing Brow Tines (G1)

Question: “We deer hunt in Uvalde County and have been trying to manage our deer. This year we have seen a 3 1/2 year old buck that would be a main frame 7 point deer if he had brow tines, but he is missing his G1s. The buck has decent beam lengths and the mass is pretty good. Will this whitetail buck ever produce brow tines in the future? The guys on our deer lease are trying to decide if we want cull this buck or leave him until next year. Should we shoot all bucks that have no brow tines to improve the deer herd or should we just wait until they are at least 4 1/2 years old?”

Response: The only way to improve the buck component of your deer herd will be to remove the bucks with unwanted antler characteristics. These deer that hunters refer to as management or cull bucks. Young bucks that have missing brow tines turn into old bucks with missing brow tines. But it gets worse. They breed each fall, spreading the gene for missing brow tines. I’ve seen ranches where most of the bucks had missing brow tines. Don’t go there!!! Continue reading Grow Bigger Bucks: Cull Bucks With Missing Brow Tines (G1)

High Fencing for Deer Management: Inbreeding Problems?

Question: “We are considering high fencing our 1,100 acre South Texas ranch in Brooks County, Texas, for increased whitetail deer management. We want to make sure we not only improve the habitat, but maintain or improve the quality of the deer on the property. Should we be concerned about inbreeding and a decline of deer quality on a relatively small place? Thanks for your opinion.”

Deer Management: I would not be concerned about the inbreeding of deer on a high fenced property of that size. You should “trap” more than enough deer when the fence is constructed so inbreeding or antler decline from inbreeding will will never be a problem. The high fence will allow you more management opportunity and flexibility, so that makes good sense if you are committed to deer management. Continue reading High Fencing for Deer Management: Inbreeding Problems?

Shooting Does with Fawns While Deer Hunting

Question: “Not sure what to do when it comes to this deer hunting scenario. I have recently started bow hunting again and I am not sure about shooting does with fawns. I have passed up several doe because of this and I am not sure if the fawns will survive the winter if I harvest the doe. I hunt in Wisconsin and the winters can be bad. I would rather see the doe and her young walk and hopefully make it through the winter than shoot the doe and have the fawns die. What is the best answer from a deer management and deer hunting standpoint?”

Deer Management: If we are asking the “shoot does with fawns” question from an ethical standpoint you first have to decide on your own. What you consider ethical may not be what other hunters classify as ethical. Same goes for the decision to shoot a fawn. From a deer management and deer numbers standpoint I could justify shooting a doe if we were trying to reduce the overall deer population or improve the buck to doe ratio. Continue reading Shooting Does with Fawns While Deer Hunting

Feeding Peanuts to Deer

Question: “We manage our 375 acres for improved deer hunting by selective harvest and supplemental feeding. And we’ve seen the benefits over the past six years. We are always looking for new, better supplements to keep our options open. Supplemental feeding< has helped our fawn production big time, but we understand that it is only a component of our overall management strategy. Have you ever fed deer peanuts for protein as supplement over the summer?

I know that peanuts are high in protein and fat, both of which can really help deer. Body condition is the key to antler growth in bucks, as well as fawn survival. My timed spin feeder can throw peanuts, without the shell of course, so I was thinking about using them this summer to provide some additional deer nutrition. Are peanuts all that different than acorns regarding nutrition for whitetail deer?” Continue reading Feeding Peanuts to Deer

Deer Management for Whitetail Deer

Question: “My brothers and I have been whitetail deer hunting together for over two decades now and we, along with some friends, finally have a deer lease that is big enough to implement a whitetail deer management program on. We’ve been on this place for four years now. Our deer lease is 7,000 acres in size and is located in southeast Kansas. We will be starting a feeding program in January and plan on putting eight 300 pound protein feeders on the property. What percent of protein would you suggest for whitetail deer, and can you give me an idea of the amount of antler gain we can expect to see down the road?

Two years ago we have adopted a 3.5 year old minimum buck age and have gone from taking bucks in the 13’0s to bucks in the 150’s. Do you think this is okay or should we raise the minimum deer age or set a minimum antler score? Thanks!” Continue reading Deer Management for Whitetail Deer

Deer Management in South Texas – What to Shoot?

Question: “I just received permission to a new South Texas ranch located just outside of Kingsville, Texas. The property owner gave me all the hunting rights to the place and placed the whitetail deer management in my hands. The ranch is 900 acres in size, but 100 acres will be planted to wheat later this week. That field will make serve as a great winter food plot. I have been seeing about 25 doe every time I drive through the ranch and corn the roads.

From my casual observations, there seem to be many more does than bucks. Most of the South Texas properties I have been on in the past have about the same number of bucks and does, but this place is skewed. Because of this, I am thinking about letting my friends and family harvest a few does this season, as well as guiding hunts off the ranch. How many does would you take off this ranch without effecting the buck to doe ratio?” Continue reading Deer Management in South Texas – What to Shoot?

Whitetail Deer Management: Deer Protein Requirements

Question: “We are interested in whitetail deer management so as to improve the deer hunting on our property located in Pennsylvania. The subject of feeding protein to deer gets mentioned a lot, and we understand that better deer nutrition leads to more fawns and bigger antlers in bucks. We already do some habitat manipulation to help the deer and we have lots of browse plants. However, we are unsure of whitetail deer protein requirements. Do you think protein is a limiting factor and would our deer would benefit from supplemental foods with high levels of protein?”

Answer: First, understand that most whitetail deer get their nutrition from plants found in their environment. So good job on your current situation. It sounds like your habitat management activities are producing a lot of high quality browse plants for deer. These browse plants are high in protein. Feeding deer, protein or otherwise, gets a lot of attention. The biggest reason is because it is the easiest thing a hunter can do. Continue reading Whitetail Deer Management: Deer Protein Requirements

Supplemental Feeding of Whitetail for Deer Management

Question: “We are interested in whitetail deer management and started a supplemental feeding program in January. I am trying to decide whether or not to continue feeding 20% protein pellets past the middle of September. Not sure. Also thinking that we will feed until it rains and then stop, but there are no clouds in sight.

I know of ranches that feed protein pellets year round and even one that is stops in early fall regardless of the habitat conditions on their property. I know supplemental feeding definitely helps the deer, and does still have fawn that they are nursing. Currently feeding protein, whole cotton seed, and some alfalfa hay. Whitetail deer are in good shape right now. What should we do?” Continue reading Supplemental Feeding of Whitetail for Deer Management