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Timothy A Bargar

Research Zoologist (Ecotoxicology)

Wetland and Aquatic Research Center

Office Phone: 352-264-3520
Fax: 352-378-4956
ORCID: 0000-0001-8588-3436

7920 NW 71st Street
Gainesville , FL 32653

Supervisor: Lynn M Copeland
This is a collection of data on the contamination of water, fish, and sediments in Biscayne National Park and in canals that discharge into the national park. The water data are estimations of their concentrations in water based on sampling with passive water samplers (semi-permeable membrane devices and polar organic chemical integrative samplers). Also in this data set are estrogen equivalencies for the chemical mixtures in the polar organic chemical integrative samplers.
The data set contains raw data for pesticide (naled) residues on samplers collected after aerial applications over the National Key Deer Refuge in the Florida Keys, and biological response (cholinesterase activity in butterflies and mosquito mortality) for organisms co-located with the residue samplers.
Recent concern for the adverse effects from neonicotinoid insecticides has centered on risk for insect pollinators in general and bees specifically. However, natural resource managers are also concerned about the risk of neonicotinoids to conservation efforts for the monarch butterfly (Danaus plexippus) and need a tool to estimate risk for wild monarch butterflies exposed to clothianidin. In the present study, monarch butterfly larvae were exposed to contaminated milkweed plants from hatch until pupation, and the effects upon larval survival, larval growth, pupation success, and adult mass were measured. Soils dosed with a granular insecticide product lead to average clothianidin concentrations of 10.8 - 843 ng/g...
Soil contamination by lead (Pb) from past small munitions training on Beale Air Force Base, California and Tyndall Air Force Base, Florida may result in adverse effects for passerine birds that utilize the locations. A study was conducted during 2016–17 at both Air Force Bases (AFB) to assess the risk of bird exposure to Pb. Two different methods were used to estimate exposure. The first was by analysis of blood and feather samples collected from birds captured on both AFBs, while the second was by food chain modeling using data on Pb concentrations in dietary items (invertebrates and seeds) collected from both AFB. Lead concentrations in blood and feathers for birds captured at Beale AFB indicate low exposure and...
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