ONA REPORT

published in

THE FLORIDA CATTLEMAN AND LIVESTOCK JOURNAL


July 2017

Feral Swine Trapping: Techniques and Common Designs

by Bethany Wight and Raoul Boughton

Ona Report - Dr. Raoul Boughton


For questions or comments regarding this publication contact: Dr. Raoul Boughton, University of Florida, IFAS


Feral swine (also called feral pigs or wild hogs) are not native to the Americas and were introduced by Spanish settlers in the 1500s. In most states, including Florida, feral swine are considered an invasive or “nuisance” species, due to the damage to agricultural and ecological habitats. The most common type of damage by feral swine is from rooting which loosens the soil, destroys native vegetation, and modifies the chemistry and nutrients of the soil. Feral swine can negatively impact not only natural ecosystems but also agricultural areas, livestock, and even residential areas. Feral swine also carry numerous diseases, some of which are transmittable to wild and domestic animals as well as humans. Controlling feral swine populations is difficult due to their high reproductive rate, as females are able to reproduce twice a year. Many control techniques are used, however trapping and removing swine is the most common method. 

Choosing Trap Locations

When choosing locations for trapping look for signs of high swine activity, such as evidence of rooting, tracks, and wallows. Sites of damage may not always be the best place to trap as swine spend most of their time in shaded areas close to a water source. It is better to scout low-lying areas such as river or creek bottoms, wetlands and forest edges. Travel routes to and from these areas are ideal for higher catch opportunities and multiple sites may increase your success. Keep in mind that vehicle access is usually essential.

Pre-baiting and Baiting

It is important to allow swine enough time to become accustomed to a location and entering the trap. Pre-baiting the location prior to trap placement attracts swine regularly to a specific site increasing trap success. After pre-baiting erect the trap, secure the gate (but do not set gate/trigger) and layout a bait trail. Monitor the trap(s) with game cameras to ensure swine are readily entering the trap for at least 3 nights. When swine are entering freely set the trap trigger and bait along the inside of the trap leading to the trigger location, as well as on the trigger. Baiting along the sides of the trap leading to the trigger will allow more swine to enter the trap before the mechanism is triggered. Common baits used include: dry or fermented corn, vegetable/produce scraps, molasses, red Kool-Aid, and commercial attractants.

Figure 1. Bait placed along the inside of the trap leading to the trigger (Photo By: Wesley Anderson, UF-IFAS).  Figure 1 and 1a. Bait placed along the inside of the trap leading to the trigger (Photo By: Wesley Anderson, UF-IFAS).

Figure 1. Bait placed along the inside of the trap leading to the trigger (Photo By: Wesley Anderson, UF-IFAS). 

Common reasons for poor trapping success

  • Bad trap placement and/or not enough pre-baiting (may require up to 2 weeks)
  • Faulty trigger or escape due to poor trap construction.
  • Too much natural food available.
  • Hunting and dogs can alter swine behavior and reduce trap success.

Two Commonly Used Traps Types:

Feral Swine Portable Cage Trap - A stronger portable trap, ideal for individual swine or small groups of swine.

Figure 2. A portable cage trap (built at Avon Park Correctional Institute, Photo By: Jesse Lewis, Conservation Science Partners).

Figure 2. A portable cage trap (built at Avon Park Correctional Institute, Photo By: Jesse Lewis, Conservation Science Partners).

  • Rectangular trap made from heavy-gauge wire livestock panels welded to steel frame or purchased from vendor.
  • Typically 4 feet wide, 6-12 feet long, and 4-5 feet high.
  • Traps <5 feet tall should have top panel or jump bars to prevent swine escape.

Purchasing Information
There are multiple vendors of cage traps below are several examples. Note: The University of Florida and IFAS do not endorse any particular company or trap type.

  • Voorhies Outdoor Products, LLC Hog Trap -  Metal trap with 3 rooter doors ($399.99)
  • Forestry Suppliers—Steel Cage Hog Trap with spring loaded door ($400.00)
  • Avon Park Correctional Institute—Work Study Program, Purchase of materials only, $500/trap.

Feral Swine Corral Trap - The most effective for trapping large groups of swine.

Feral Swine Corral Trap - The most effective for trapping large groups of swine.

Figure 3. A coral trap, effective for trapping large groups of swine (Photo By: Mississippi State University Extension Service: Office of Agricultural Communications).

  • Constructed from livestock panels fastened to T-posts using U-bolts and cable clamps.
  • Using 3-4 5’ by 16’ panels should make a trap large enough to catch most sounders.
  • Can vary in shape but are typically round to prevent swine from piling up in corners and possibly climbing or jumping out.

Material

Quantity

Estimated Cost

16’ by 5’ Panel

3

$50-70each

61/2’ T-posts

10

$4.50/each

5/16 cable clamps

12

$1.50/each

5/16 by 1 1/2’ U-bolts

24

$2.00/each

 

TOTAL

Approx. $290.00

Gate Types

There are many variations in design and materials used for trap gates. Most are made from steel or wood. Choosing the type of gate to use depends on your budget, ease of transport and the trap being used. The four basic gate types are:
1) Drop Gate or Guillotine - Inexpensive and easily constructed. Gate is suspended by trigger line, once triggered gate will drop close. Single-catch only.
2) Swing or Saloon Gate - pivot towards inside and held with a trigger line. Once triggered heavy springs close gate quickly. If not padded can be noisy and frighten other swine. Multi-catch. 
3) Rooter or Lift Gate - hinged top of gate allows one way entry into trap. Can also be set open and then drop close with a trigger. If not padded can be noisy and frighten other swine. Multi-catch.
4) Funnel Entry - ends of mesh panel constructed as funnel in which swine must push through to enter trap. Tynes on edge of mesh panel entry prevent swine from pushing back out. Quiet closure.

Trigger Mechanisms

Two major types of trigger mechanisms are used when trapping wild swine: a rooter stick and a trip wire. For both, the trigger pulls a line which causes the gate to fall or swing close.
Rooter Stick

  • A stick is wedged beneath two holding stakes in or around a bait pile. The stick is triggered when the swine feed and root around, pushing the rooter stick out from under the holding stakes
  • Stick is holding weight of gate so swine must push weight of gate to dislodge stick or a pin can be used.

Figure 4. An example of a rooter stick trigger mechanism. 
Trip Wire

  • A line or wire is buried under bait or suspended slightly above the ground attached to a triggering device (pin or shackle) that will release the gate when pressure is exerted on the line.
  • Many different designs. ( Design below by USDA Wildlife )

Figure 5 and 5a. Trip wire trigger design using a shackle. Design by USDA Wildlife Service.Figure 5 and 5a. Trip wire trigger design using a shackle. Design by USDA Wildlife Service.

Figure 5. Trip wire trigger design using a shackle. Design by USDA Wildlife Service.

Humane Trapping and Disposal

Although wild swine are a nuisance species, they are living animals that register pain and stress. Steps should be taken to minimize stress and insure they are disposed of humanely.
Humane Trapping

  • Traps should be checked at least once daily and placed somewhere with shelter or shade.
  • Traps should be constructed to minimize injury, smaller mesh size should be used to avoid snout injury. 4” by 4” is the minimum recommendation.

Humane Disposal

  • Swine should be disposed of quickly using a .22 caliber rifle or larger.
  • Do not insert the rifle barrel into the trap, through the side panels. Swine may charge and hit barrel, potentially causing you or someone else injury. Instead shoot through the panels or down into the trap.
  • Two possible sites for a quick, humane brain shot:
    • Frontal shot - center of the forehead, placed about 2-3” above an imaginary line directly between the eyes and aimed toward spine.
    • Oblique shot – from behind the ear and aimed towards the opposite eye
  • Careful not to shoot directly between the eyes as this is the beginning of the nasal cavity and will not result in a rapid death.

Additional resources and information for this document can be found from:

Hamrick, Bill, Smith, Mark, Jaworowski, Chris, and Bronson Strickland. 2011. A Landowner’s Guide for Wild Pig Management: Practical Methods for Wild Pig Control. Mississippi State University Extension Service & Alabama Cooperative Extension System. Available at https://extension.msstate.edu/sites/default/files/publications/publications/p2659_0.pdf

Mayer, John J. and. I. Lehr Brisbin Jr. Wild Pigs: Biology, Damage, Control Techniques and Management. Savannah River National Laboratory, Aiken, NC. Available at http://www.wildpigconference.com/docs/SRNL-Mayer-Biology%20Damage%20Control.pdf

Mitchell, Jim. 2011. Trapping of Feral Pigs. NQ Dry Tropics, Townsville, AU. Available at http://www.sugarresearch.com.au/icms_docs/182981_Trapping_of_feral_pigs.pdf

Shearer, J.K. and A. Ramirez. 2013. Humane Euthanasia of Sick, Injured and/or Debilitated Livestock. Iowa State University Extensions. Available at https://vetmed.iastate.edu/sites/default/files/vdpam/Extension/Dairy/Programs/Humane%20Euthanasia/Download%20Files/EuthanasiaBrochure20130128.pdf

West, Ben C., Cooper, Andrea L., and James B. Armstrong. 2009. Managing Wild Pigs: A Technical Guide. Human Wildlife Interactions Monograph 1:1-55. Available at http://berrymaninstitute.org/files/uploads/pdf/managing-feral-pigs.pdf