title: Effects of esfenvalerate on the reproductive success of the bluegill sunfish, Lepomis macrochirus in littoral enclosures.
abstract: Adult bluegills were exposed to the synthetic pyrethroid esfenvalerate, during a reproduction study conducted in six littoral enclosures located in a 2-ha pond near Duluth, Minnesota. Bluegill reproductive success was determined after two applications of esfenvalerate at nominal concentrations of 0.0, 0.01, 0.08, 0.20, 1. 0, and 5.0 microg/L. Responses measured were adult behavior and spawning, embryo hatchability, larval survival until swim-up, young-of-the-year (Y-O-Y) growth, and total biomass. All adult bluegills died within one day following the first application at 5.0 microg/L. Successful spawning and resulting hatching of offspring were observed at all esfenvalerate concentrations except 5.0 microg/L. Following exposure at 1.0 microg/L, spawning was delayed for 15 days and few or no larvae survived. Bluegill Y-O-Y growth was reduced by 62, 57, and 86% in the 0.08, 0.20, and 1.0 microg/L esfenvalerate treated enclosures. Delayed adult spawning and reduced Y-O-Y growth may result in poor Y-O-Y overwinter survival which would result in a diminished or extirpated year class.
authors.affiliation: National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Mid-Continent Ecology Division-Duluth 6201 Congdon Boulevard, Duluth, Minnesota 55804, USA.
authors.forename: D K
authors.initials: DK
authors.lastname: Tanner
authors.forename: M L
authors.initials: ML
authors.lastname: Knuth
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D018533:Biomass; D004791:Enzyme Inhibitors / Q000633:toxicity*; D005260:Female; D007306:Insecticides / Q000633:toxicity*; D008297:Male; D009570:Nitriles; D010473:Perciformes / Q000254:growth & development / Q000502:physiology*; D011722:Pyrethrins / Q000633:toxicity*; D011897:Random Allocation; D012098:Reproduction / Q000187:drug effects*; D014874:Water Pollutants, Chemical / Q000378:metabolism / Q000633:toxicity; D015048:Zooplankton / Q000187:drug effects / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; D014874:Water Pollutants, Chemical; C017690:fenvalerate