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Timothy Bargar, Ph.D.

Tim Bargar moved joined the USGS in 2008 and has worked to build research collaborations with federal partners to evaluate contaminant impacts on the nation’s trust resources. 


My research has emphasized assisting natural resource managers dealing with contaminant risks to DOI-trust resources. In ecotoxicology, risk is a function of the exposure magnitude for contaminants and toxicity. Often exposure/toxicity information available in the literature has limited applicability to the in-the-field situations, which could lead to decisions with much uncertainty. When there are competing unrelated priorities, the need for better data becomes increasingly urgent. My research program has focused on providing better data for issues concerning resource managers such as neonicotinoid insecticides and monarch butterflies, mosquito control insecticides and imperiled butterflies, and sunscreen chemicals and coral reefs. My goal is to help resource managers with these data needs so that they can achieve their trust resource conservation goals. 


His dissertation investigated a potential non-lethal, non-invasive method for assessing oviparous organism exposure to persistent organic contaminants. Prior to joining the  U.S. Geological Survey, Dr. Bargar worked with the National Oceanic and Atmospheric Administration, the U.S. Environmental Protection Agency, and the U.S. Fish and Wildlife Service. While with NOAA, he participated in the investigation of pesticide impacts in the Everglades National Park while completing his PhD. He moved on to the Office of Pesticide Programs of the USEPA where his responsibility was the conduct of pesticide ecological risk assessments within the Federal Insecticide, Fungicide, and Rodenticide Act process. He then joined the South Florida Ecological Services Office of the USFWS in 2003 and participated in activities related to the Comprehensive Everglades Restoration Plan (CERP). His responsibilities primarily involved the assessment, and associated ecological risks to federally listed species, of contamination on properties acquired for incorporation within the CERP. Additional responsibilities included evaluation of pesticide risk to federally listed species as a result of pesticide use on national wildlife refuges.