Secondary poisoning risks from 1080-poisoned carcasses and risk of trophic transfer—a review

Abstract

In New Zealand, sodium fluoroacetate (1080) is used for the control of unwanted terrestrial vertebrate pests, some of which are carriers of bovine TB, and for the conservation of native flora and fauna. One key advantage of 1080 used for animal pest control is that it is biodegradable. In this short review, we focus on the persistence of 1080 in carcasses and the risk of 1080-poisoned carcasses to dogs, and the possible risk of toxicity in other non-target species via trophic transfer. The slower breakdown of 1080 in poisoned carcasses under certain conditions (e.g. cold, dry conditions), and the risks of secondary poisoning, have to be understood and managed following use of this toxin in conservation or as part of TB eradication programs. Poisoned possum carcasses can pose a risk to dogs even up to 75 days after the control operation. Lower, less hazardous concentrations have been found in deer bone marrow after 213 days. When other species (e.g. insects or birds) come into contact with 1080 in carcasses, sub-lethal poisoning is more likely. In these cases, as with sub-lethal poisoning in any non-target animals, any 1080 ingested will be metabolised and excreted, and trophic transfer will be minimal when compared to more persistent poisons.