deer

To survive long enough to grow trophy-sized antlers, deer have to survive a number of hurdles, including predators, range conditions, vehicles and disease.

Better start saving your money because this could be the deer season you make a trip to your local taxidermist.

From border to border, what started out as a bizarre year in Texas with sub-zero winter temperatures turned into an ideal spring and summer for antler development.

Each year Texas hunters take between 800,000 and a million white-tailed deer during the archery, regular and extended Managed Land Deer Permit seasons. Yet the statewide deer population stands strong at an estimated 5.4 million.

While a whitetail can live to be 8½ years old or older in the wild, it is amazing that they do. From the time they are born, deer face a number of obstacles in surviving outside hunting — ranging from habitat conditions, predators, weather extremes, collisions with vehicles, fighting, stress from the rut and disease.

According to the Texas Parks and Wildlife Department, fawn survival statewide this year is expected to be 45 to 50%, a high number considering it is typically below 40%. The reason for the higher survival is a mild spring and summer that provided plenty of food and water for the young deer and their mothers.

Studies have shown predator impact on a fawn population is going to vary depending on predator density, deer density, habitat quality and time of the year. Coyotes and bobcats are more likely to target fawns as newborns and again during late winter. Depending on all the variables, predators can account for 10 to 90% of fawn loss in a year.

Texas does not keep count of deer/vehicle collisions, but ask any insurance agent or body shop and they will say it is substantial. Numbers go up dramatically during the rut and in years in which deer have to hunt for food.

Diseases are another issue. Two, anthrax and Chronic Wasting Disease, stand out in Texas. Epizootic Hemorrhagic Disease also exists in the state, but it does not result in the herd decimation it does elsewhere.

“Arkansas is the closest state to Texas with confirmed EHD cases, but keep in mind we have EHD in Texas as well, but often don’t test for it,” explained Alan Cain, TPWD white-tailed deer program leader. “I had a ranch I work with that lost 20-plus deer last summer to EHD.”

EHD is a viral disease similar to bluetongue that is transmitted by flies and mosquitos.

“Deer in Texas have been exposed to EHD for years and generally have an innate resistance and built up titers. This natural immunity is passed along from adult does to their fawns. So most native deer are not impacted by EHD,” Cain said.

Although not a statewide issue, anthrax is a major issue in southwest Texas in Val Verde, Uvalde, Kinney, Real and Edwards counties. A major outbreak can be devastating to localized herds.

Anthrax is a bacteria existing in the soil that can be disrupted by wet weather in the spring and early summer followed by dry and hot temperatures. Cattle can be vaccinated against the disease and humans can be successfully treated if discovered early. There is no vaccine or treatment for wildlife.

“There is not much that can be done to prevent anthrax. Since anthrax spores are found in the soil, the best practice to possibly minimize impacts is to ensure you have good ground cover in the form of grass and forbs. That means proper grazing management and keep stocking rates at reasonable levels,” Cain said.

Chronic Wasting Disease is the most publicized deer disease. In Texas it has been found in free-ranging, but fortunately has not resulted in massive dieoffs the biologists worried about. It is more common in deer farming populations, including cases found this year in Hunt County resulting in a restricted zone in portions of Hunt, Kaufman, Rockwall and Van Zandt counties.

The disease was first found in Texas in 2012. In all, CWD has been found in 26 states and three Canadian provinces.

“Through regulations and statewide surveillance efforts, we’ve been able to detect and monitor CWD in both free-ranging and captive deer. Implementation of CWD zones, restrictions on carcass movement from CWD zones or other CWD positive states and provinces, restrictions on live animal movements, and enhanced CWD testing requirements for captive cervids has been helpful in containing CWD,” Cain said.

Working together, TPWD and the Texas Animal Health Commission continue efforts to identify outbreaks, educate the public and create regulations to restrict the disease’s impact.

“Thus far, CWD in free-ranging deer appears to be contained within the current CWD zones that have regulation in place intended to contain the disease. At this time there is no immediate concern of large-scale free-ranging deer population declines in Texas as a result of CWD, but we must be vigilant and proactive in our CWD surveillance and management efforts to prevent this scenario from becoming a reality,” Cain said.

Of course this being 2021 there cannot be a discussion of diseases without a mention of COVID-19. A study in four upper Midwest states showed the antibodies of the disease existed in 40% of wild deer sampled. Researchers believed that while the deer were somehow infected they developed antibodies to thwart it.

“TPWD is not testing for COVID in the native deer species. We do not believe there are any concerns for hunters when in contact with harvested deer. As always we would recommend hunters follow safe handling practices when field dressing or processing deer,” Cain said.

Disease is not a new issue for Texas’ white-tailed deer. In the 1950s the state’s deer population along with its livestock industry was nearly destroyed by screwworms. In the 1960s it was discovered the release of millions of sterile male screwworm flies across the Southern U.S. would halt the disease.

That in a big part, along with management and hunter participation, has resulted in a $2.2 billion deer hunting industry in Texas.

 
 

TWITTER: @PhilHicksETFS

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