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Element concentrations in nestling tree swallows (Tachycineta bicolor) from the U.S. and Binational Great Lakes’ Areas of Concern: Data

Metadata Updated: October 29, 2023

Tree swallow, Tachycineta bicolor, nestlings were collected from 76 sites in the Great Lakes which included multiple sites at 27 Areas of Concern (AOCs) and 12 sites not listed as AOCs from 2010 to 2015. Livers were harvested and analyzed for 21 elements. Mercury concentrations differed among AOCs; however, all livers analyzed had concentrations well within background and generally comparable or lower than most sites outside of the Great Lakes. Mercury, the only element specifically identified in the designation of AOCs, does not seem to pose a threat to birds at any of the AOCs monitored. In contrast, selenium (Se) concentrations were elevated at sites on the southwest shore of Lake Michigan to levels that could be harmful to reproduction. Other toxic elements were elevated at selected AOCs, but the concentrations were not at toxic levels. Multivariate analysis identified concentration pattern differences among 8 AOCs that had 3 or more sites sampled. Of 29 possible AOC comparisons, 11 were significant and clear differences in patterns were evident. Concentration patterns of sites within AOCs appeared closely associated with one another. Additionally, Se was the primary contributor to the differences among the 8 AOCs for 9 of the 11 comparisons.

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Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Created Date June 1, 2023
Metadata Updated Date October 29, 2023

Metadata Source

Harvested from DOI EDI

Additional Metadata

Resource Type Dataset
Metadata Created Date June 1, 2023
Metadata Updated Date October 29, 2023
Publisher U.S. Geological Survey
Identifier USGS:5ce16e0be4b0170a8bca95ca
Data Last Modified 20210908
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id c9e8103e-e318-4e70-aede-310dafad1cc2
Harvest Source Id 52bfcc16-6e15-478f-809a-b1bc76f1aeda
Harvest Source Title DOI EDI
Metadata Type geospatial
Old Spatial -180.0,-90.0,180.0,90.0
Publisher Hierarchy White House > U.S. Department of the Interior > U.S. Geological Survey
Source Datajson Identifier True
Source Hash 113e14b4859e41e4544a62b47dfbc392277449e87cac6daa957c2f8d55a6ee46
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -180.0, -90.0, -180.0, 90.0, 180.0, 90.0, 180.0, -90.0, -180.0, -90.0}

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