Brian C. Balmer Joseph P. Skorupa Katherine B. Adams Bridger M. Creel Gregory Hoffman Megan A. Fylling Stephanie Le Jacob M. Martin Theresa L. McBride Jacob T. Williams Molly A. Moloney Travis S. Schmidt 20250604 Comma-separated value (CSV) https://doi.org/10.5066/P1JRQP8U This data release includes nest box field observations (N = 98 nest boxes) and avian egg tissue laboratory analyses (N = 60 eggs) collected from Lake Koocanusa (also known as Koocanusa Reservoir) and the Kootenai River Basin, Montana, 2022-2023. Nest box field observation data (occupancy rate, clutch size, and hatching success) and avian eggs were collected by the U.S. Fish and Wildlife Service (USFWS) Montana Ecological Services Field Office (Helena, Montana), in cooperation with the University of Montana Bird Ecology Lab (Missoula, Montana), U.S. Army Corps of Engineers-Seattle District, Libby Dam-Kootenai River, (Libby, Montana), and U.S. Geological Survey (USGS) Wyoming-Montana Water Science Center (Helena, Montana). Preparation of egg tissue samples for metal(loid) analyses were conducted by the USFWS Montana Ecological Services Field Office and USFWS Mountain-Prairie Region (Lakewood, Colorado). Laboratory analyses [metal(loid)s] were conducted by the U.S. Environmental Protection Agency (USEPA), Region 10 Laboratory (Port Orchard, Washington). Specific metal(loid)s analyzed in avian egg tissue were arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), manganese (Mn), nickel (Ni), selenium (Se), and zinc (Zn). This data release also compiles laboratory quality-assurance (QA) and quality-control (QC) data associated with the avian egg samples. These data were collected for an initial assessment evaluating avian secondary cavity nester, specifically tree swallow, population demographics and potential threats associated with open-pit mining upstream of Lake Koocanusa (also known as Koocanusa Reservoir) and the Kootenai River in the Elk River Watershed, British Columbia, Canada. 20220502 20230628 ground condition Complete None planned Lake Koocanusa (also known as Koocanusa Reservoir) and Kootenai River Basin -115.4744 -115.1088 48.9993 48.3527 ISO 19115 Topic Category biota USGS Thesaurus Selenium Ecosystem monitoring Bioaccumulation Birds Migratory species USGS Metadata Identifier USGS:6765f76dd34e5335adae3686 Common geographic names Lake Koocanusa Kootenai River Basin Montana None Tree Swallow Black-capped Chickadee Western Bluebird Spotted Sandpiper Kingdom Animalia Subkingdom Bilateria Infrakingdom Deuterostomia Phylum Chordata Subphylum Vertebrata Infraphylum Gnathostomata Superclass Tetrapoda Class Aves Order Passeriformes Family Hirundinidae Genus Tachycineta TSN: 178426 Family Paridae Genus Poecile Species Poecile atricapillus Family Turdidae Genus Sialia Species Sialia mexicana TSN: 179806 Order Charadriiformes Family Scolopacidae Genus Actitis Species Actitis macularius None. Please see 'Distribution Info' for details. Although these data have been used by the USFWS and USGS, U.S. Department of the Interior, no warranty expressed or implied is made by the USFWS and USGS as to the accuracy of the data. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USFWS and USGS in the use of these data, software, or related materials. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. This dataset may be redistributed if it is not edited and is properly referenced. Although USGS intends to make this server available 24 hours a day, seven days a week, timely delivery of data and products from this server through the internet is not guaranteed. Brian Balmer U.S. Fish and Wildlife Service Environmental Contaminants Specialist mailing and physical

585 Shephard Way, Suite 1

Helena Montana 59601 USA 406-437-2077 brian_balmer@fws.gov U.S. Fish and Wildlife Service, Montana Ecological Services Office, Helena, Montana, USA, U.S. Fish and Wildlife Service, Mountain-Prairie Region, Lakewood, Colorado, USA, U.S. Environmental Protection Agency, Region 10 Laboratory, Port Orchard, Washington, USA, University of Montana Bird Ecology Lab, Missoula, Montana, USA, U.S. Army Corps of Engineers-Seattle District, Libby Dam-Kootenai River, Libby, Montana, USA, U.S. Geological Survey, Wyoming-Montana Water Science Center, Helena, Montana, USA. The collection of tree swallow eggs was conducted under U.S. Fish and Wildlife Service Scientific Collecting Permit Number MBPER0028656 and Montana Fish, Wildlife, and Parks Scientific Collector’s Permit Numbers 2022-001-W and 2023-016-W. This project would not have been possible without the dedicated efforts of numerous field and laboratory researchers including Ashley Bussell, Dr. Creagh Breuner, Dr. Ben Colman, Gerald Dodo, Meghan Dunn, Michelle Fillion, Danie Frevola, Larry Fulford, Jason Gildea, Robin Kockler, Lisa Kusnierz, Karen Nelson, David Rouse, and Dr. Forrest Townsend. We are also extremely appreciative of Dr. Christine Custer and Paul Dummer’s insights and expertise into nest box sampling design and tree swallow biology. No formal attribute accuracy tests were conducted by the U.S. Fish and Wildlife Service, Montana Ecological Services Field Office. Avian egg tissue samples were analyzed by U.S. Environmental Protection Agency, Region 10 Laboratory (Port Orchard, Washington), with its own quality-assurance and quality-control (QA/QC) procedures. All data were broadly checked for accuracy, and no obvious outliers were present. No formal logical accuracy tests were conducted. Dataset is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. Nest box field observations and collection of avian eggs were collected by the USFWS Montana Ecological Services Field Office (Helena, Montana), in cooperation with the University of Montana Bird Ecology Lab (Missoula, Montana), U.S. Army Corps of Engineers-Seattle District, Libby Dam-Kootenai River, (Libby, Montana), and USGS Wyoming-Montana Water Science Center (Helena, Montana). Field observations and egg collection were conducted under standardized protocols (UMBEL, 2024). University of Montana Bird Ecology Lab (UMBEL). 2024. Evaluating songbird response to contamination and anthropogenic disturbance. Field Protocols for Nest Box Monitoring, Nestling Banding, and Collection of Biological Samples. Missoula, Montana. 48 pp. All scientific names applied to nest box field observations and collection of avian eggs were validated using Poole and Gill (2020). A. F. Poole, F. B. Gill (Eds.). 2020. Birds of the World. Cornell Lab of Ornithology, Ithaca, NY. https://birdsoftheworld.org/bow/species/ 20230628 Preparation of egg tissue samples for metal(loid) analyses were conducted by the USFWS Montana Ecological Services Field Office and USFWS Mountain-Prairie Region (Lakewood, Colorado). Laboratory analyses [metal(loid)s] were conducted by the USEPA, Region 10 Laboratory (Port Orchard, Washington). For both preparation of egg tissue samples and subsequent laboratory analyses, protocols are discussed in detail in the Koocanusa Reservoir/Kootenai River Swallow Egg Selenium Study Quality Assurance Project Plan (QAPP), US EPA and US FWS, Revision Number 1, April 18, 2022, approved April 29, 2022. Lab analytical methods are discussed in detail in USEPA (2014, 2016). Balmer, B., Brown, D., and Kusnierz, E. 2022. Koocanusa Reservoir/Kootenai River Swallow Egg Selenium Study Quality Assurance Project Plan (QAPP). U.S. Fish and Wildlife Service, U.S. Environmental Protection Agency. Helena, Montana. 40 pp. USEPA. (2014). Method 6020B (SW-846): Inductively Coupled Plasma-Mass Spectrometry. Revision 2. Washington, DC. https://www.epa.gov/sites/default/files/2015-12/documents/6020b.pdf USEPA. (2016). Method 3052. Microwave Assisted Digestion of Siliceous and Organically Based Matrices. In: U.S. EPA, Ed., Test Methods for Evaluating Solid Wastes: Physical/Chemical Methods, EPA SW-846, Third Edition, Chap. 3 (Inorganic Analytes).Washington, DC. https://www.epa.gov/sites/default/files/2015-12/documents/3052.pdf 20230628 Data were reviewed, no outliers were detected, and then compiled into three, comma-separated value (CSV) files for release [1-Nest box demographics, 2-Egg metal(loid) concentrations]. 20241219 QA/QC data (analysis duplicates and analysis spikes) and certified reference material data provided by the USEPA, Region 10 Laboratory (Port Orchard, Washington) were compiled for this data release. 20241219 0.0001 0.0001 Decimal degrees World Geodetic System 1984 (WGS 84) WGS 84 6378137.0 298.257223563 Koo_Egg_Metalloid_2022_2023.csv The CSV file contains metal(loid) concentrations in dry weight, milligrams/kilograms (mg/kg) and distance from U.S./Canada border in kilometers for all nest boxes. Producer Defined Species_code Avian species four letter code from the Bird Banding Laboratory of the North American Bird Banding Program. Producer Defined SPSA Spotted Sandpiper Producer defined TRES Tree Swallow Producer defined WEBL Western Bluebird Producer defined BCCH Black-capped Chickadee Producer defined Nest_box_site Unique descriptor for each nest box site (three letter code). Producer Defined OSS Ospreyland Nest Box Site Producer defined LIS Libby Dam Nest Box Site Producer defined ROS Rocky Gorge Nest Box Site Producer defined SAS Sand Hill Nest Box Site Producer defined YAS Yarnell Nest Box Site Producer defined ZES Zegler Nest Box Site Producer defined MCS McGuire Nest Box Site Producer defined STS Stone Hill Nest Box Site Producer defined Nest_box_number Unique numeric descriptor for each nest box. Producer Defined NA No data associated with sample Producer defined 12 100 Year Year of data collection. Producer Defined 2022 2023 Year, YYYY Collctn_date Day, month and year of data collection (DD/MM/YYYY). Producer Defined 5/25/2023 6/8/2023 Month/Day/Year (MM/DD/YYYY) Moisture_Percent Percent moisture measured from egg sample. Producer Defined 68.1 86.9 Percentage Arsenic_dw_mg_kg Arsenic concentration (dry weight, milligrams/kilograms) measured from egg sample. Producer Defined 0.2 0.4 dry weight, milligrams/kilograms Cadmium_dw_mg_kg Cadmium concentration (dry weight, milligrams/kilograms) measured from egg sample. Producer Defined 0.0 0.2 dry weight, milligrams/kilograms Chromium_dw_mg_kg Chromium concentration (dry weight, milligrams/kilograms) measured from egg sample. Producer Defined 0.4 4.9 dry weight, milligrams/kilograms Copper_dw_mg_kg Copper concentration (dry weight,milligrams/kilograms) measured from egg sample. Producer Defined 1.5 3.9 dry weight, milligrams/kilograms Lead_dw_mg_kg Lead concentration (dry weight, milligrams/kilograms) measured from egg sample. Producer Defined 0.1 0.5 dry weight, milligrams/kilograms Manganese_dw_mg_kg Manganese concentration (dry weight, milligrams/kilograms) measured from egg sample. Producer Defined 1.4 7.5 dry weight, milligrams/kilograms Nickel_dw_mg_kg Nickel concentration (dry weight, milligrams/kilograms) measured from egg sample. Producer Defined 0.4 1.5 dry weight, milligrams/kilograms Selenium_dw_mg_kg Selenium concentration (dry weight, milligrams/kilograms) measured from egg sample. Producer Defined 1.7 4.7 dry weight, milligrams/kilograms Zinc_dw_mg_kg Zinc concentration (dry weight, milligrams/kilograms) measured from egg sample. Producer Defined 43.0 87.9 dry weight, milligrams/kilograms Distance_from_US_Canada border_km Distance of each nest box to U.S./Canada border, calculated using the “Measure” tool in ArcMap 10.8.1 (ESRI, Redlands, California, U.S.). Producer Defined 9.9 121.5 kilometers, km Koo_Field_Data_2022_2023.csv The CSV file contains nest box identification, latitude, longitude, occupancy, clutch size in number of eggs, hatching success as a percent, and distance from U.S./Canada border in kilometers for all nest boxes. Producer Defined Collctn_yr Year of data collection. Producer Defined 2022 2023 Year, YYYY Site_id Unique three letter code descriptor for each nest box site. Producer Defined BOS Border Site Producer defined LIS Libby Dam Site Producer defined OSS Ospreyland Site Producer defined ROS Rocky Gorge Site Producer defined SAS Sand Hill Site Producer defined STS Stone Hill Site Producer defined YAS Yarnell Site Producer defined ZES Zegler Site Producer defined KBS Koocanusa Bridge Site Producer defined MCS McGuire Site Producer defined Site_name Unique full site name for each nest box site based on three letter Site_ID code. Producer Defined Border Nest Box Site Producer defined Libby Dam Nest Box Site Producer defined Osprey Land Nest Box Site Producer defined Rocky Gorge Nest Box Site Producer defined Sand Hill Nest Box Site Producer defined Stone Hill Nest Box Site Producer defined Yarnell Nest Box Site Producer defined Zegler Nest Box Site Producer defined Koocanusa Bridge Nest Box Site Producer defined McGuire Nest Box Site Producer defined Sample_id Unique numeric descriptor for each nest box. Producer Defined NA No data associated with sample. Producer defined Unique numeric descriptor for each nest box. Latitude Latitude of individual nest box Latitude (decimal degrees, WGS 84 datum). Producer Defined 48.3732 48.9989 Decimal degrees (DD.MMMM) 0.0001 Longitude Longitude of individual nest box (Latitude (decimal degrees, WGS 84 datum). Producer Defined -115.4524 -115.1670 Decimal degrees (DD.MMMM) 0.0001 Distance_from_US_Canada border_km Distance from each nest box to U.S./Canada border, calculated using the “Measure” tool in ArcMap 10.8.1 (ESRI, Redlands, California, U.S.). Producer Defined NA No data associated with sample. Producer defined 3.0 121.5 kilometers Species_code Avian species four letter code from the Bird Banding Laboratory of the North American Bird Banding Program. Producer Defined NA No data associated with sample. Producer defined TRES Tree Swallow Producer defined SPSA Spotted Sandpiper Producer defined BCCH Black-capped Chickadee Producer defined WEBL Western Bluebird Producer defined Occupancy Presence or absence of at least one egg observed in each nest box. Producer Defined NA No data associated with sample. Producer defined 0 Egg absent Producer defined 1 Egg Present Producer defined Clutch_size Total number of eggs laid within each nest box in which incubation was observed. Producer Defined NA No data associated with sample. Producer defined 1 7 Eggs Hatching_success_percent Total number of nestlings observed divided by the total number of eggs counted during incubation. Producer Defined NA No data associated with sample. Producer defined 0 100 Percent Koo_Egg_QAQC_2022_2023.csv The CSV file contains QA/QC data (analysis duplicates and analysis spikes), and certified reference material data provided by the USEPA, Region 10 Laboratory (Port Orchard, Washington). Producer Defined Lab_id Sample identifier assigned by the USEPA laboratory. Producer Defined Sample identifier assigned by the USEPA laboratory. Analysis_dt Date of laboratory analysis. Month/Day/Year (MM/DD/YYYY) Producer Defined NA No Data Producer defined 1/9/2024 12/6/2023 Month/Day/Year (MM/DD/YYYY) QAQC_analysis_type Type of analysis conducted for QA/QC. Producer Defined Percent_recovery Analyzing laboratory percent recovery = 100 x [(spiked sample concentration - unspiked sample concentration)/effective spike concentration]. Producer defined Duplicate Duplicate sample Producer defined Percent_moisture Analyzing laboratory percent moisture of tissue = (wet weight - dry weight)/wet weight. Producer defined Matrix_spike_percent_recovery Analyzing laboratory matrix spike percent recovery = 100 x [(spiked sample concentration - mean unspiked sample concentration)/effective spike concentration]. Producer defined Matrix_spike_percent_recovery_dup Analyzing laboratory matrix spike percent recovery duplicate = 100 x [(spiked sample concentration - mean unspiked sample concentration)/effective spike concentration]. Producer defined Method_blank Method blank is prepared and analyzed by the laboratory to ensure the accuracy of analytical methods. Producer defined Method_blank_percent_moisture Analyzing laboratory method blank percent moisture of tissue = (wet weight - dry weight)/wet weight. Producer defined DUP_percent_moisture Analyzing laboratory percent moisture duplicate of tissue = wet weight - dry weight)/wet weight. Producer defined Analyte Constituent or characteristic measured by laboratory. Producer Defined Lead Metal(loid) Producer defined Manganese Metal(loid) Producer defined Nickel Metal(loid) Producer defined Arsenic Metal(loid) Producer defined Cadmium Metal(loid) Producer defined Chromium Metal(loid) Producer defined Copper Metal(loid) Producer defined Zinc Metal(loid) Producer defined Selenium Metal(loid) Producer defined Moisture Percent moisture Producer defined Result Laboratory analysis result. Producer Defined 0.1 112.0 Percent, % or milligrams per killograms, mg/kg Unit Unit of laboratory analysis result. Producer Defined Percent Percentage Producer defined mg/kg milligrams/kilograms Producer defined Result_basis Result basis reported by laboratory. Producer Defined NA No data associated with sample. Producer defined Dry weight Dry weight Producer defined Dilution_factor Dilution factor = (sample aliquot + acid blank used for dilution)/ sample aliquot. Producer Defined Dilution factor = (sample aliquot + acid blank used for dilution)/ sample aliquot. Lab_name Laboratory that conducted analysis Producer Defined Region 10 Lab USEPA, Region 10 Laboratory (Port Orchard, Washington) Producer defined Lab_qualifier Laboratory-defined qualifier. Producer Defined NA No data associated with sample. Producer defined U The material was analyzed for, but was not detected above the level of the associated value. Producer defined GS ScienceBase U.S. Geological Survey mailing address

Denver Federal Center, Building 810, Mail Stop 302

Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Digital Data https://doi.org/10.5066/P1JRQP8U None 20250604 Brian Balmer U.S. Fish and Wildlife Service Environmental Contaminants Specialist mailing and physical

585 Shephard Way, Suite 1

Helena Montana 59601 USA 406-437-2077 brian_balmer@fws.gov FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata FGDC-STD-001.1-1999