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Individual study: Pacific rat Rattus exulans eradication on Dekehtik Island, Federated States of Micronesia, Pacific Ocean

Published source details

Wegmann A., Braun J. & Neugarten R. (2008) Pacific rat Rattus exulans eradication on Dekehtik Island, Federated States of Micronesia, Pacific Ocean. Conservation Evidence, 5, 23-27

Summary

As part of a larger project attempting to reduce predation pressure from introduced rats Rattus spp. on native fauna and flora on several islands off Pohnpei main island (Pacific Ocean), a rat eradication program was undertaken on the small island of Dekehtik (2.63 ha) where Pacific rats R.exulans were present. The island was systematically hand-broadcast with rodenticide bait at a pre-determined application rate of 50 kg/ha over one day. Radio-tracking revealed that rats spent a significant amount of time in the forest canopy. Therefore, to ensure that rats living in the canopy had a good chance of encountering bait, bait clusters (bolo baits) were fabricated and catapulted into one third of the palm trees on the island. Pre-bait application trap success (rat captures/trap nights) was 52%. Post-bait application trap success (as recorded 12-15 days after bait application) was 0%. Although rat chew marks were found on one wax indicator block 12 days after the bait application, subsequent monitoring detected no rats. No non-target species appeared adversely effected by the rodenticide bait.