Monitoring mortality of brown treesnakes fed an oral toxicant (acetaminophen) in an external bait placement dosing technique in the laboratory, 2017

Accidentally introduced to Guam, the brown treesnake (BTS) has extirpated nearly all native forest birds and imposed cost millions of dollars in economic damages annually. Acetaminophen is a safe and effective oral toxicant for invasive BTS, and an automated aerial delivery system (ADS) has been developed for landscape-scale distribution and snake suppression. An 80 milligram dose has proven 100% lethal for most BTS; however, there have been no previous trials that compared internal versus external placement of the oral toxicant on the bait and how that affects mortality of individuals. This study compared mortality following exposure to three treatments: placement of the toxicant inside a dead mouse bait, placement of the toxicant on the surface of a dead mouse bait, and water soaked (rainfall exposed) toxicants on the surface of a dead mouse bait. External placement of the toxicant was found to be as effective as internal placement.