Funding Program: Contaminant Biology

Statement of Problem: This work is a new project to determine the rodenticide-related consequences of eradication of rats adversely impacting threatened or endangered native species in Hawaii, entitled: Determination of Diphacinone Residues in Sea Water, Invertebrates, Vertebrates and Bait Pellet Formulations Following Eradication of Polynesian Rats (Rattus exulans) from Mokapu Island, Hawaii, February 2008; listed under CERC # 08-CHEM-08. The project supports CERC missions related to environmental studies and assessments. Our partner in this effort is The Hawaii Wildlife Society, who has an interest in protecting the natural resources in the identified study are on Mokapu Island, Maui, HI. The HWS is providing funding to USGS in the for the processing and analysis of water and tissue samples collected in February 2008, as part of a demonstration of the use of rodenticides to eradicate rats impacting native flora and fauna.

Objectives: The proposed USGS project entails preparation and analysis of sea water, invertebrate tissues, vertebrate tissues, and Ramik® Green (0.005% active ingredient) bait samples for diphacinone residues. The samples represent a collection from the February 2008 eradication study conducted by the USFWS. The United States Fish and Wildlife Service, Hawaii Division of Forestry and Wildlife has recently overseen aerial broadcast of the bait, with subsequent collection of samples.