Brodifacoum residue analysis in water, soil, invertebrates, and birds after rat eradication on Lady Alice Island
- Manaaki Whenua - Landcare Research, P.O. Box 69, Lincoln, Canterbury, New Zealand
- Department of Conservation, P.O. Box 842, Whangarei, New Zealand
Rats were eradicated from Lady Alice Island (Northland, New Zealand) in October 1994, using aerially applied cereal-based bait containing brodifacoum. To determine the fate and non- target impact of brodifacoum, streams, soil, invertebrates, and birds were monitored for 7 months after the baits were applied. No brodifacoum was detected in any of the stream or soil samples. Brodifacoum was detected in cave weta found on baits, and in morepork and red-crowned parakeet liver tissue. Significant contamination of water and soil is unlikely after a single aerial application of brodifacoum baits. Invertebrates such as cave weta may be at risk of consuming brodifacoum bait, morepork and red-crowned parakeet may be at risk of secondary poisoning.