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.
RESEARCH
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.
BACKGROUND
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.
Science and Products
Contaminants Assessment in the Coral Reefs of the Virgin Islands National Park and Virgin Islands Coral Reef National Monument
Environmental Management of Vector-borne Diseases
Effect of Chronic Neonicotinoid Insecticide Exposure upon Monarch Development
Risk of Adult Mosquito Control Pesticides to Imperiled Butterflies
Monarch Butterfly Utilization of Milkweed Plants Grown in Close Proximity to Corn Treated by a Neonicotinoid Insecticide (Seed Treatment)
Baseline Aquatic Contamination and Endocrine Status in Resident Fish Populations of Biscayne National Park and in the Adjacent Coastal Environment
Methylmercury Impacts to Reproduction in the Eastern Mosquitofish (Gambusia holbrooki)
Mosquito Control Pesticide Impacts to Butterflies: Implications for Imperiled Butterfly Conservation on a National Wildlife Refuge
Science and Products
- Publications
- Science
Contaminants Assessment in the Coral Reefs of the Virgin Islands National Park and Virgin Islands Coral Reef National Monument
USGS collected samples at reef locations within the Virgin Islands National Park and analyzed for the presence of contaminants, organotin compounds, or sunscreen compounds.Environmental Management of Vector-borne Diseases
Effective management programs for vector-borne pathogens, such as West Nile Virus and the Lyme disease spirochete, are necessary to protect public health. However, some vector control methods, such as landscape manipulations and pesticide applications, can also adversely affect nontarget species and environmentally sensitive natural systems. Efficient targeting and integration of vector control...Effect of Chronic Neonicotinoid Insecticide Exposure upon Monarch Development
The long-term viability of monarch butterfly (Danaus plexippus) populations in North America is in doubt.Risk of Adult Mosquito Control Pesticides to Imperiled Butterflies
Mosquito control on Department of the Interior (DOI) managed lands is a resource management challenge. The pesticides used to control mosquitoes may also affect nontarget organisms whose conservation is one of the primary responsibilities of resource managers.Monarch Butterfly Utilization of Milkweed Plants Grown in Close Proximity to Corn Treated by a Neonicotinoid Insecticide (Seed Treatment)
Monarch butterfly populations have declined sufficiently to result in noticeably fewer overwintering at sites in central Mexico as in California.Baseline Aquatic Contamination and Endocrine Status in Resident Fish Populations of Biscayne National Park and in the Adjacent Coastal Environment
As part of the Comprehensive Everglades Restoration Plan, water managers are planning to use treated wastewater from the South District Wastewater Treatment Plant (WWTP) to supplement the canal waters that will be used to rehydrate wetlands adjacent to the Biscayne National Park (Park).Methylmercury Impacts to Reproduction in the Eastern Mosquitofish (Gambusia holbrooki)
USGS researchers investigate the effects of methylmercury contamination on reproduction of the Eastern mosquitofish, a common fish in South Florida.Mosquito Control Pesticide Impacts to Butterflies: Implications for Imperiled Butterfly Conservation on a National Wildlife Refuge
USGS researchers evaluate the impact of a pesticide on two imperiled butterfly species in the Florida Keys. - Data
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