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We conducted ground-based surveys at 589 randomly selected 16-ha plots on the Yukon-Kuskokwim Delta, Alaska during 2015-2016. The plots were selected using a stratified random sampling plan in an area of 35,769 square km divided into 8 physiographic strata. The population totals from the stratified random design estimators were adjusted using detection ratios derived with a double sampling protocol (Bart and Earnst 2002) on a subset of plots in Alaska.The subset of plots used for double sampling included 17 study plots on the Yukon Delta National Wildlife Refuge (9 plots in 2001-2002 [McCaffery et al. 2012] and 8 plots in 2016), and 33 plots located on the North Slope of Alaska (Utqiaġvik [6 plots, 2014–2015], the...
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We conducted population and habitat assessments for Mountain Plovers in Texas during winters of 2019 and 2020. We used roadside surveys and distance-sampling to estimate bird density and calculate population totals for the study area, which included parts of five ecoregions (Chihuahuan Deserts, High Plains, Central Great Plains, Southern Texas Plains, Texas Blackland Prairies, and Western Gulf Coastal Plain). In 2019, we surveyed 103 transects along 3,032 km (1,884 mi) and, in 2020, we surveyed 152 transects along 4,985 km (3,098 mi). When driving along transects, we stopped every 3.2 km (2 mi) to assess habitat conditions (vegetation height, vegetation density, etc.) and land cover (National Land Cover Database...
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Principal to the management of migratory landbird resources is an understanding of their occurrence within the landscape. Baseline information on bird distribution is a primary need “to preserve a natural diversity and abundance of fauna and flora on refuge lands” (U.S. Fish and Wildlife Service [USFWS] 1993a). Documenting the occurrence and distribution of all migratory bird species is a priority of the USFWS’s action plan for developing a nongame bird inventory and monitoring strategy for National Wildlife Refuge system lands (USFWS 1993b ). Distribution and abundance information previously collected on National Wildlife Refuges has contributed to the description of distributional patterns of birds in Alaska....
    map background search result map search result map Mountain Plover population and habitat assessments in Texas, 2019–2020 Breeding Shorebird Surveys on the Yukon-Kuskokwim Delta, Alaska, 2015-2016 Alaska National Wildlife Refuge Avian Checklist Project 1991-2000 Alaska National Wildlife Refuge Avian Checklist Transcribed Data 1988-2000 Mountain Plover population and habitat assessments in Texas, 2019–2020 Breeding Shorebird Surveys on the Yukon-Kuskokwim Delta, Alaska, 2015-2016 Alaska National Wildlife Refuge Avian Checklist Project 1991-2000 Alaska National Wildlife Refuge Avian Checklist Transcribed Data 1988-2000