FERAL SWINE: RESEARCH NEEDS AND SUMMARY
BILLY HIGGINBOTHAM, Texas Agricultural Extension Service, P. O. Box 38, Overton, Texas 75684
Three years have passed since I first realized the passion in the public’s voice on the subject of feral hogs. It happened in March of 1990 at a feral hog seminar entitled “Feral Hogs: The Good, the Bad, or the Ugly?”. The program was conducted in the tiny town of Cayuga, Texas by the Texas Agricultural Extension Service. On one side were the landowners, with faces red and veins popping out in their temples as they spoke of damage to crops, winter pasture and coastal bermudagrass meadows by marauding feral hogs. On the other side of the Cayuga High School cafeteria were the hunters, speaking warmly of this supplemental game species that extended their hunting season to 12 months. The dog hunters in attendance echoed the sentiments of the other hunters, and quickly offered their services to the landowners, who by the way, were still standing on their side of the room. Caught square in the middle was a minority that did not know quite what to think, including me.
I have thought about that night in Cayuga many times over the past three years. There are few other species that the public holds stronger feelings for, both pro and con. Hog populations continue to increase at least in Texas. As a result, there appears to be some truth to the saying that in Texas, there are only 2 kinds of landowners: those with feral hogs, and those that are about to get feral hogs!
This broad spectrum of attitudes has been evident in the breadth of subject matter addressed during our conference. But what are the future research needs? It would be difficult indeed to throw a dart and miss the target. In Texas, we have an estimated 4 million white-tailed deer, and the research that has been and will be conducted on the species is voluminous. In contrast, we may also be home to half that many feral hogs (and still counting), yet the research conducted pales in comparison to white-tailed deer studies. There is much that needs to be known about this most interesting (take your pick): (a) game animal, (b) predator, (c) disease vector and/or (d) crop depredator.
As biologists, it seems only natural to first select the biology of the feral hog as a starting point for research. Much is known about the basic life history of the feral hog, and its certainly no mystery that many aspects of domesticated swine biology easily carry over to their wilder counterparts. We know of its tremendous reproductive potential, exemplified in a statement by International Paper Company biologist David Whitehouse when he said “a sow may give birth to an average of 4-6 piglets, but 8 survive!” Three basic tenets of feral hog life history that remain both vague and evasive to those curious include population estimation, home range/movements and age determination. Although there have been a number of excellent studies, we remain less than comfortable with what we know as compared to the management techniques, strategies and data available for the white-tailed deer.
The interaction of feral hogs with other wildlife species has certainly been documented. Niche overlap may not be a problem at low population densities, on certain habitat types or during certain seasons, but is that assumption universal? Certainly our state and national park systems are victims of the damage hog populations can impose on environmentally sensitive habitats and their endemic plant and animal communities. Then there is the potential impact on ground-nesting species, particularly quail and turkeys. Is the mortality caused by egg-loving hogs reason for serious concern? We must also conclude from previous studies that sheep and goat predation is common and deer fawns may become prey under certain conditions.
In addition to being predators, feral hogs also have the distinction of being prey. Pumas and black bears reportedly prey on feral hogs in California. Preliminary data suggest that another predator, the coyote, may also benefit from expanding feral hog populations. Numerous landowners report increased sightings of coyotes as hog populations increase, indicative of a classic predator-prey relationship.
Next are crop and pasture depredation, which quickly raises the ire of affected farmers and ranchers. These problems are often complicated by landownership patterns, where tract sizes are decreasing and absentee landownership is increasing. The hogs that visited your cornfield or winter pasture last night may spend their days in a thicket a mile away behind four “No Trespassing” signs and three barbed wire fences — and you may not have any idea to whom that thicket belongs. Efficient baits and attractants are needed for trapping and approved species specific toxicants may be warranted in certain cases to control (but certainly not eliminate) depradation problems.
The disease implications of feral hog populations are well documented. The greatest danger appears to be the potential impact on domesticated swine, particularly via pseudorabies and swine brucellosis. However, other species that come in contact with feral swine, including humans, are not immune from the effects of their diseases. Widespread supplemental stocking of feral hogs has certainly contributed to the spread of disease. The potential threat of these stockings in Texas has resulted in regulations prohibiting indiscriminate stocking of feral hogs until blood tests are drawn and screened by a veterinarian.
I have addressed a number of largely negative aspects and potential problems regarding feral hogs, yet there still remains a positive side, the “Good” in the “Good, the Bad and the Ugly.” One fact cannot be ignored — feral hogs, as a game animal, are a potential source of supplemental income. The average price paid for a Texas hog hunt is estimated to be $ 169.00. We have heard from a group of panelists that realize the income potential of this resource, and market the recreational opportunities associated with that resource successfully.
In addition, associations and magazines founded to promote the wild boar are solid indicators of its popularity. Field trials are now being conducted on a regular basis, showcasing both bay and catch dogs. Specialty meat processors have also realized and exploited the marketability of feral hog as an exotic meat. Marketing research on expanding feral hog utilization for sporthunting as well as for tablefare is needed to align “producers” with their potential clientele.
So where does it end? Certainly not with this conference. If anything, we hope that the past two days will provide opportunities for collaboration between biologists, scientists, landowners and hunters to identify, address and hopefully solve common problems associated with feral swine. The feral hog has survived and expanded its range since first introduced by Hernando de Soto to the Florida coast in 1539, and from all indications, they are certainly here to stay. Let’s use this conference as a springboard for future study of one of the most interesting animals of inter-national distribution, the feral hog.