Daily and Landscape Influences of Species Visitation to Toxic Bait Sites for Wild Pigs

Authors

Nathan P. Snow, USDA APHIS Wildlife ServicesFollow
Joseph M. Halseth, USDA/APHIS/ Wildlife Services, National Wildlife Research Center
Michael P. Glow, USDA National Wildlife Research Center
Michael Lavelle, USDA, Animal and Plant Health Inspection ServiceFollow
Justin Fischer, USDA-APHIS-Wildlife ServicesFollow
Eric H. VanNatta, USDA/APHIS/ Wildlife Services, National Wildlife Research Center
Kurt C. Vercauteren, APHISFollow

ORCID IDs

NATHAN P. SNOW http://orcid.org/0000-0002-5171-6493

MICHAEL J. LAVELLE http://orcid.org/0000-0002-2766-5673

Document Type

Article

Date of this Version

2021

Citation

Wildlife Society Bulletin 45(1):109–120; 2021

DOI: 10.1002/wsb.1159

Comments

This article is a U.S. Government work and is in the public domain in the USA.

Abstract

Toxic baiting of wild pigs (Sus scrofa) is a potential new tool for population control and damage reduction in the United States. Use of toxic bait sites by non‐target species is concerning because of the risks posed from exposure to a toxic bait. A 2018 field trial in northern Texas, USA, examining the efficacy of a prototype toxic bait (HOGGONE®, containing 10% sodium nitrite) revealed unexpected hazards to non‐target species, primarily passerine birds, from consuming toxic bait spilled outside of bait stations by wild pigs. The hazards jeopardize the ability to register HOGGONE as a tool for controlling wild pigs. We conducted a post hoc analysis from that 2018 trial to identify how daily and landscape factors influenced the use of bait sites by non‐target species, and subsequent hazards from consuming the toxic bait. We discovered that no single strategy can eliminate visitations by all non‐target species, but offering the toxic bait at night, in wild‐pig specific bait stations, and in more homogeneous landscapes appeared to be the best strategy for minimizing visits by passerine birds. We also found that use of bait sites by wild pigs were temporally clustered, and more pigs visited bait sites along linear features of the landscape (e.g., agricultural edges or riparian corridors). We recommend a baiting strategy where applicators do not place bait stations directly at sites where remnant particles of grain (from prebaiting) are available on the ground.