Wild Pigs Strategic Planning for Managing the Unwanted Neighbor

Written by Aaron Sumrall, PhD

Pig Brig Field Engine Wildlife Research Vice President - Outreach and Research aaron@pigbrig.com

Land ownership trends over the last decade have been very dynamic, to say the least, with many new rural landowners coming from urban settings. These landowners quickly find themselves at a decision-making crossroads as they learn about land stewardship and best management plans. With any good plan, one must start with realistic goals for the property and work backward. In learning about stewardship, the damage and conservation challenges caused by non-native invasive species are evident. The most notorious nonnative invasive on the Texas landscape is the wild pig (Sus scrofa), with an expanding population and impacts ranging from hundreds of millions in crop damage to native habitat degradation.

A strategic mitigation effort to remove wild pigs from your land should start with data collection. You must understand your current situation before you establish land management goals and a best management plan. Due to the nomadic tendencies of wild pigs and large family (“sounder”) ranges, game cameras are the quickest and easiest way to conquer this task. Such cameras positioned on game trails, food sources, water sources, or scent stations can collect sufficient data to devise an approach for resident wild pig management. You’ll quickly learn the number of pigs and size of sounders using your property. You might even be able to identify individuals based on coat patterns. You can also witness sounder dynamics, better understand where they travel, favorite food sources, and see any non-target species in the area.

Essential data points from your game camera data are the number of pigs and sizes of the sounders. When scouting specifically for wild pig sounders, you will need to set the camera to allow the manager to determine the color of wild pigs after dark. This setting will likely require a relatively technical camera with no flash or a less expensive option requiring a flash. The color of pigs in a sounder can help you identify the number and size based on the individuals’ physical appearance (color) in the group. Managers can also determine an individual’s or group’s overall health, indicating the potential for successful management. Thin wild pigs are a good indicator of a diminishing landscape function, thus less food availability, increasing the probability of successful trapping efforts.

Sounder dynamics are one often overlooked aspect of wild pig management. This oversight quickly pushes a well-meaning control plan into the meaningless category. To hold localized wild pig populations stable, managers must remove a minimum of 70% of the population annually. The only path to this math is to use an integrated pest management plan with trapping at its core. It is critical to know the dynamics and number of sounders in your area, the individual number of wild pigs in each sounder, and the number of lone boars in the area.

The strength of a sounder is in the number of individuals within. On any given landscape, there will likely be multiple sounders overlapping in the use of available resources. There will be a single dominant sounder with varying insubordinate sounders, each led by a dominant female. Trapping efforts may require multiple traps in a single location to remove the occupying sounders quickly. Wild pigs are creatures of habit. Sounders will develop a typical pattern that lends itself to trap sites for mitigation efforts. Managers should focus on one location for trapping, staying close to the area where the dominant sounder most frequently visits while potentially adding sites to trap insubordinate sounders. If this is not a possibility, managers will then need to identify a location that best covers the area of overlapping sounders with a trap that will allow the catch of multiple sounders in a single catch event. Many trapping options only catch the first visiting sounder. This trap style educates subsequent visiting sounders to the trap location and removal efforts. Trapping can be further complicated when attempting to remove boars as they are typically solitary and encounter traps only after the initial capture.

Adding to the discussion of sounder dynamics are the individuals that make up the sounder. Managers must closely assess camera images, specifically looking for any small piglets in the sounder. The presence of small pigs in a sounder will tell the manager that they should expedite the removal effort. Sows with small piglets will be highly nomadic as a predatory response. Predators seek out small piglets as a relatively easy food source, and sows keeping piglets in an area for a prolonged time will allow predators to home in on sounders and feed on these young individuals. Once pigs reach weaning, they are typically large enough to thwart the efforts of native predators. Young sows may take a litter or two to figure this out.

Many well-intentioned wild pig management plans are rendered useless because managers did not use data collected on non-target species occupying the landscape. Raccoons, deer, squirrels, and flocking birds pose the highest probability of spoiling trapping efforts due to the manager incorrectly using the data. Conventional trapping efforts use a catch gate and manual trigger that the wild pigs must trip. Unfortunately, non-target species do the same if the selection of a trigger is not considered. If deer are the non-target concern, trip strings will not work. Trip strings, however, are the correct choice for a trigger if your concern is raccoons. Strings of any type are unsuitable if flocking birds (like Blackbirds) or squirrels will perch or walk on your string and impact your success. High populations of predatory animals, such as coyotes and bobcats, can cause wild pigs to be almost perpetually on the move. Food sources in a landscape will always be in a temporary state. Farmers will harvest crops, and hardwoods will drop mast crop in the fall. These are examples of changes that will dictate travel patterns for wild pigs throughout the year. The location and abundance of a food source will determine travel patterns and the length of time pigs will be in an area. It is critical to decide when you have decreasing or low nutritional availability on your landscape. During such times, the probability of trapping success will increase. The best trapping times of the year are from December/ January to bud break in the spring and during the summer heat when conditions are typically under drought stress.

Managers who successfully control their wild pig populations and develop a sound integrated management approach are focused on the initial phases of scouting, data collection, and analysis. While not the most exciting task, detailed data collection will help determine the most appropriate equipment, the best time to capture, and most importantly, how many sounders are remaining on the landscape. This base knowledge will set a bigger plan in motion, including decisions about pre-baiting, baiting, and program duration.