January 06, 2017
Depending on your chosen profession, you either love or hate feral pigs. This lack of middle ground creates a problem between hunters and agricultural stakeholders.
Most readers of this magazine view wild pigs as a challenging, tasty, big-game species that can be hunted year-round in most states as a form of recreation.
However, farmers, ranchers, and wildlife biologists see an invasive species creating an annual negative economic impact of $1.5 billion in environmental damage, soil erosion, and agricultural damage. This group would like to see feral swine controlled more efficiently.
I have either attended or been a speaker at every International Wild Pig Conference and Wildlife Damage Management Conference since 2006. The common theme at every national conference is sport hunters are ineffective at controlling feral swine populations.
As feral hog populations and conflicts continue to increase throughout the United States, so does the interest in ways to control the problem. This article is intended to educate hunters how to successfully implement a productive solution instead of being viewed as part of the problem.
Understanding the Problem
Legal game populations, such as deer, turkey and quail, are effectively managed in most states by hunters during a specific, annual hunting season with a daily or annual bag limit. But wild pigs are not game animals.
They are considered an invasive, non-game species in most states with no closed hunting season and no bag limit. This means hunters and land managers may harvest an unlimited number of wild pigs 365 days per year. Yet, annual statistics confirm traditional hunting and trapping methods fail to effectively control wild pig populations. The methodology must change to achieve more efficient results.
Know thy enemy is the key to feral swine control success. There are four unique conditions that make wild pig control different from conventional wildlife management. First, young females (gilts) reach sexual maturity at 6 to 8 months delivering their first litter of (4-6) piglets around their first birthday and produce two litters of (6-10) piglets annually as mature females (sows) thereafter.
Their gestation period is 114 days or three months, three weeks and three days. No other large animal is capable of producing multiple large broods every year starting at such an early age. Their high reproduction rate gives feral pigs the capacity to recover quickly from most control efforts.
Second, pigs are the fourth smartest animal on the planet behind dolphins, chimpanzees, and elephants. Domestic pigs have been trained in an academic environment to operate a joystick and move a cursor on the screen. Pigs performed this task at a rate comparable to monkeys and learned faster than three-year-old humans playing the same game. Their high intelligence is the reason wild pigs are so quickly educated during failed control attempts, which leads to future trap avoidance.
They form small social groups called "sounders" based on a maternal hierarchy and adapt their patterns to a wide range of habitats. The dominant sow leads the sounder and often changes their location and home range to exploit seasonal food sources during various mast and crop cycles. Adult males (boars) are mostly solitary. Groups of young boars under 18 months of age form "bachelor" groups and travel separately from sow and pig sounders.
Third, pigs have an incredible sense of smell. One way scientists measure an animal's ability to smell is by counting the number of genes in their DNA related to scent. Humans have 387 active olfactory receptor genes. Dogs have double the amount with 811. Pigs have a remarkable 1113 active genes related to smell. Their sense of smell is so good, pigs can discriminate between mint, spearmint, and peppermint with 100 percent accuracy during academic testing. They are capable of sensing odors five miles away and able to detect food sources several feet underground.
The fourth factor is human perception and human dynamics. As conservationists, hunters are taught it is unethical to harvest juveniles (deer fawns, elk calves, bear cubs, etc.) since they are game animals. Traditional approaches are used to manage game animals producing only one or two offspring per year and will not control an invasive species producing 12 to 20 piglets annually.
Mainstream media perform a horrible job educating the public because high-volume hog control is not a politically correct topic the average citizen wants to hear or is mentally prepared to understand. Hunting networks glorify big boars as a trophy game animal while only televising mature animal harvests per episode, much like deer or elk hunting. Some hunters are even responsible for spreading the pig population by illegally relocating them specifically to start new hunting opportunities. Annual statistics confirm traditional hunting and trapping methods fail to effectively control this invasive species.
Integrated Wild Pig Control
The JAGER PRO definition of Integrated Wild Pig Control (IWPC) is "a strategic approach using a series of innovative lethal control methods and technologies implemented in a specific sequence based on seasonal food sources. Emphasis is placed on efficient removal of the entire sounder at one time to eliminate escapes, education, and reproduction. The control strategies continually change throughout the various seasons to effectively target adaptive survivors. The control strategies must continually change throughout the various seasons to effectively target adaptive survivors."
Winter months (late December to late March) provide the optimal trapping opportunity as hogs are searching for new food sources. This is usually the coldest time of year, and hogs must burn more calories to stay warm. The fall mast crops of acorns and hickory nuts have been eaten and no other agricultural row crops are planted. It is much easier to bait wild pigs to automatic feeders in the winter than any other season.
The IWPC winter strategy is to capture entire sounders of juvenile pigs, sub-adults, nursing sows and pregnant sows, as they pattern to these supplemental bait sites. This tactic will eliminate 70-80 percent of the total property population in 90 days when performed correctly.
High-volume trapping is an art not science. Every sounder will consist of various age groups, juvenile to adult ratios, population sizes, and education levels. Therefore, the key to efficient trapping using IWPC standards is to incorporate a process whereas the individual sounder dictates the time period between steps. This information is based on photo/video observations (intelligence) gathered from the bait site.
Three Important Steps to Our Capture Success Matrix
1. Condition pigs to trust the bait site as a daily food source.
2. Condition pigs to trust the corral enclosure as a daily food source.
3. Utilize the optimal trigger device for 100 percent capture of the entire sounder.
We accomplish Step One by strategically erecting automatic feeders with digital timers every 250-300 acres apart on the property. For this example, we erect 10 feeders on 2,500 acres Monday morning. This ensures we are targeting multiple home ranges and helps us quickly identify the number of sounders on the property and the population dynamics of each by analyzing camera data within the first week.
Later in the week we discover 15 pigs arrive at Feeder #2 after dusk then travel to Feeder #3 before midnight. A second sounder of 20 pigs appear at Feeder #9. The following Monday morning we recover all feeders except #2 and #9. Step One has been accomplished when the entire sounder has fed multiple nights in a row and are now conditioned to trust the individual bait site as a daily food source.
Only then may we begin Step Two of the Capture Success Matrix by erecting a M.I.N.E. (Manually Initiated Nuisance Elimination) Trapping System to condition pigs to trust the corral as a daily food source. Narrow gates, thresholds, and frames on the ground will prevent trap-shy adults from entering a trap. Gates should be a minimum of eight feet wide with no visible thresholds to step over.
Round traps provide the largest trap area for materials used, and there are no corners for the animals to pile up and jump out. The most efficient trapping design in our five-year research was a 35-foot diameter corral trap using six 18-60 trap panels and an eight-foot-wide M.I.N.E. Gate.
The final step is to utilize the optimum trigger device for 100 percent capture of the entire sounder. Camera intel from Step One already established the total sounder population and juvenile to adult ratio. Typically, higher juvenile ratios equate to quicker captures.
Most piglets and sub-adults have not been educated yet and enter the trap enclosure during the first 24 hours. Adult sows may observe their offspring feeding inside the trap for several days before trusting the enclosure enough to cross the gate threshold themselves. The IWPC standard is to immediately capitalize on this mistake the first time it happens as we may not receive a second chance.
The M.I.N.E. Cam (cellular wireless) camera sends intel photos to a cell phone, e-mail or app when the PIR motion sensor detects movement. Cellular SIM cards or data plans typically cost less than $25 per month for unlimited pictures from the target location. Cameras are positioned opposite the trap gate to properly view pigs still outside the enclosure.
Remote-control technology allow users to send text messages or utilize a smartphone app to communicate with the camera and trigger the M.I.N.E. Gate closed from their home or office. This equipment saves fuel, time, and labor, allowing 24-hour surveillance without wasting daily travel time and expenses to multiple bait sites.
A human makes an educated decision to close the gate when the entire sounder is counted inside the enclosure via texted photo while the user is offsite in another location. This approach demonstrates whole sounder removal in less than six days at most bait sites.
Spring months (March, April, and May) provide the optimal shooting opportunities at night and will target an additional 10-20 percent of the feral swine population. Row crops and spring food plots are being planted while snakes, frogs, and toads are coming out of hibernation.
There are too many food sources available for traps to be effective. The control strategy must switch to night shooting operations using infrared optics mounted on AR platform semiautomatic rifles. High-volume shooting strategies are needed to target dominant boars and bachelor groups who avoided winter corral traps and are now destroying spring plantings.
Summer months (June, July, and August) will focus on eliminating the remaining population. It is important to remember the final 10 percent of pigs on the property have already avoided corral traps with 8-foot-wide thresholds and survived previous shooting engagements at night. The remaining pigs have a higher intelligence quotient because they have been educated from earlier failed attempts.
Therefore, the seasonal control strategy must also change to target their summer wallows, pine rubs, water sources, food sources, and trails. Total time and labor needed to remove the final 10 percent of the population may require a higher number of hours used to remove the first 90 percent.
Fall months (September, October, and November) will target the remaining wild pigs on the property. The seasonal control strategy must identify fall food sources, such as maturing row crops (i.e., corn, peanuts, grain, sorghum) and falling mast crops (acorns, hickory nuts). A hybrid combination of methods and technology is needed. Also, increased fall deer hunting pressure from neighboring landowners may force new populations of feral pigs onto the property.
Solving a farmer's wild pig problem is a year-round process which takes considerable time, effort and skill.
The main goal is to efficiently solve the farmer's crop damage problem. Even high-volume removal methods will solve the problem only for a few months until another sounder of feral pigs migrate from a neighbor's property, nearby creek, or river system.
Extensive feral swine control can be accomplished only if stakeholders and hog control operators are working together to implement IWPC methods and standards throughout the entire county. This is more than just a feral swine problem. It is also a human dynamics problem.