Divergent trends in distribution and abundance of landbirds in low and high elevation habitats of the Kaʻū Rainforest

Seth Judge; Kevin W. Brinck; Ayesha Genz; Lainie Berry; Jacqueline M. Gaudioso-Levita; Alexander Wang; Richard J. Camp

doi:10.36967/2303786

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Divergent trends in distribution and abundance of landbirds in low and high elevation habitats of the Kaʻū Rainforest

Seth Judge·Kevin W. Brinck·Ayesha Genz·Lainie Berry·Jacqueline M. Gaudioso-Levita·Alexander Wang·Richard J. Camp

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Abstract

Federal, state, and non-governmental partners resurveyed landbirds in the Kaʻū Rainforest on the Island of Hawai‘i in 2019. Point-transect distance sampling was conducted in Hawaiʻi Volcanoes National Park, Kaʻū Forest Reserve, Kapāpala Forest Reserve, and Kapāpala Cooperative Game Management Area. This is the first comprehensive survey of the region since 2008. Through a collaborative effort, monitoring transects were consolidated to provide a consistent, repeatable sampling frame for future surveys. We estimated landbird distribution, density, and abundance for eight surveys since 1976. Changes in species-specific densities were assessed using a log-linear regression to determine trends of the six most recent surveys since 2002. Trends were assessed in three strata: low elevation (<1,500 m), high elevation (≥1,500 m), and total survey area.

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Source-reported bounding extent: 19.059582122258277° to 19.36476047437779° latitude; -155.6953500294963° to -155.4290276642252° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Seth Judge, Kevin W. Brinck, Ayesha Genz, Lainie Berry, Jacqueline M. Gaudioso-Levita, Alexander Wang, Richard J. Camp. 2024. Divergent trends in distribution and abundance of landbirds in low and high elevation habitats of the Kaʻū Rainforest. https://doi.org/10.36967/2303786

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