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Strata boundaries for nesting Wedge-tailed Shearwater (Ardenna pacifica) surveys at Kīlauea Point National Wildlife Refuge, Kauaʻi, in 2019

Metadata Updated: December 11, 2025

We used a stratified-random sampling approach to estimate the total abundance of Wedge-tailed Shearwater (Ardenna pacifica) nest sites across Kīlauea Point National Wildlife Refuge (KPNWR), Kauaʻi, during 1-7 July 2019. We first identified strata as unique geographic areas of the refuge to account for potential differences in nesting habitat and non-uniform nest site clustering. We then sub-divided strata where we expected high, low, minimal, or no nest site abundance. These distinctions were based on knowledge of shearwater nesting distribution gained while performing extensive ground-searching for tropicbirds across the entire refuge in April and May 2019. We delineated strata boundaries using recent satellite imagery in ArcGIS (version 10.7) and, based on direct observations in the field, refined in order to remove large contiguous areas lacking shearwater presence or nesting habitat. Planar area of each polygon was automatically calculated by ArcGIS. To calculate surface area in each stratum, we obtained a 1/3 arc-second (10-m resolution) digital elevation model from the National Elevation Dataset (USGS 2013). This elevation raster was projected to Universal Transverse Mercator projection (Zone 4 North, North American Datum 1983) and converted to a surface area raster using the raster and sp packages in R (Hijmans 2019; Pebesma & Bivand 2005). We calculated stratum-specific surface area by summing the surface area values of raster cells in each stratum using XToolsPro (version 18; Zonal Statistics tool) in ArcMap (version 10.7). Hijmans RJ. 2019. raster: Geographic Data Analysis and Modeling. R package version 3.0-7. https://CRAN.R-project.org/package=raster Pebesma EJ, Bivand RS. 2005. Classes and methods for spatial data in R. R News 5(2):9-13. U.S. Geological Survey. 2013. USGS NED n23w160 1/3 arc-second 2013 1 x 1 degree ArcGrid: U.S. Geological Survey. Accessed at https://www.sciencebase.gov/catalog/item/581d21dae4b08da350d53be2

Access & Use Information

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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Dates

Metadata Created Date September 12, 2025
Metadata Updated Date December 11, 2025

Metadata Source

Harvested from DOI USGS DCAT-US

Additional Metadata

Resource Type Dataset
Metadata Created Date September 12, 2025
Metadata Updated Date December 11, 2025
Publisher U.S. Geological Survey
Maintainer
Identifier http://datainventory.doi.gov/id/dataset/usgs-5fc54c8cd34e4b9faad88832
Data Last Modified 2020-12-08T00:00:00Z
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Metadata Catalog ID https://ddi.doi.gov/usgs-data.json
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 34b63e3b-ebdf-484a-9a45-4fa1d2eb3fea
Harvest Source Id 2b80d118-ab3a-48ba-bd93-996bbacefac2
Harvest Source Title DOI USGS DCAT-US
Metadata Type geospatial
Source Datajson Identifier True
Source Hash fae070ee883d6f811ec390f3fac35ce4f9b71ee2bd4b4b6db93b44d5cee15c0c
Source Schema Version 1.1

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