Sumrall, Samuel Aaron (2011-05). Abatement Strategies and Disease Assessment for Feral Hogs in East Texas. Doctoral Dissertation.
Feral hogs (Sus scrofa) are considered an exotic, free-ranging ungulate distributed within numerous countries and continents to include the United States. The reproductive efficiency, lack of predators, land use practices for domestic livestock (e.g., feeding stations, introduced water sources, intense cropping practices, etc.), and diet are leading factors in the expansion of feral hogs throughout their range. Feral hogs negatively impact floral and faunal communities, agricultural lands, and residential and recreational areas to include concerns with public safety and disease transmission. My study objectives were to (1) assess feral hog abatement strategies by (A) evaluating trap designs with the inclusion of electrical fencing, and (B) evaluating candidate baits for feral hog-specificity, and (2) assess prevalence levels for feral hog diseases. I evaluated 3 corral trap designs differing in the addition of electric fence configurations. Feral hog capture success data were collected and used to determine trap design efficacy. Treatments evaluated included (A) control corral trap with no electrical configurations, (B) corral trap with 1 electrical leg, and (C) corral trap with 2 electrical legs. ANOVA analyses suggest no differences (df = 2, P = 0.758) between trap designs; however, length of trapping effort (i.e., the number of days that trapping occurred) was a significant (df = 6, P < 0.001) factor in determining trap success. Pre-baiting was an important factor in observed trapping success. Trapping success declined after fourth day of continuous trapping. I recommend short, intensive trapping efforts (e.g., <4 days) when using corral traps in feral hog abatement programs. I also evaluated 14 candidate baits (with and without repellant) replicated 40 times to determine feral hog specificity. Three evaluated baits (i.e., PIGOUT(TM) strawberry, corn, and rice) were selected (df = 2, P < 0.05) more frequently by feral hogs than other combinations. Non-target species (e.g., raccoons) visited baits with repellants less (df = 2, P < 0.05) than baits without repellants. Repellant had no direct impact on feral hog visitation at bait sites. Trapping data also suggests that grains commonly farmed in local or regional areas are more likely to be consumed by feral hogs and, therefore considered in baiting options. Finally, of 412 feral hogs captured, 86 were sampled for prevalence of pseudorabies and Brucella suis. The prevalence of pseudorabies and B. suis was 20.9% and 13.9%, respectively within the study area. Based on disease study results, I recommend that natural resource managers take necessary precautions to protect themselves by wearing protective equipment and equipment and properly cooking feral hog meat. Additionally, resource managers should properly administer vaccinations to domestic and companion animals, and restricting domestic and companion animals from areas of high risk (e.g., carcasses of dead hogs and wallows).