Landscape genetics identifies streams and drainage infrastructure as dispersal corridors for an endangered wetland bird

Ecology and Evolution
By: , and 

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Abstract

Anthropogenic alterations to landscape structure and composition can have significant impacts on biodiversity, potentially leading to species extinctions. Population‐level impacts of landscape change are mediated by animal behaviors, in particular dispersal behavior. Little is known about the dispersal habits of rails (Rallidae) due to their cryptic behavior and tendency to occupy densely vegetated habitats. The effects of landscape structure on the movement behavior of waterbirds in general are poorly studied due to their reputation for having high dispersal abilities. We used a landscape genetic approach to test hypotheses of landscape effects on dispersal behavior of the Hawaiian gallinule (Gallinula galeata sandvicensis), an endangered subspecies endemic to the Hawaiian Islands. We created a suite of alternative resistance surfaces representing biologically plausible a priori hypotheses of how gallinules might navigate the landscape matrix and ranked these surfaces by their ability to explain observed patterns in genetic distance among 12 populations on the island of O`ahu. We modeled effective distance among wetland locations on all surfaces using both cumulative least‐cost‐path and resistance‐distance approaches and evaluated relative model performance using Mantel tests, a causal modeling approach, and the mixed‐model maximum‐likelihood population‐effects framework. Across all genetic markers, simulation methods, and model comparison metrics, surfaces that treated linear water features like streams, ditches, and canals as corridors for gallinule movement outperformed all other models. This is the first landscape genetic study on the movement behavior of any waterbird species to our knowledge. Our results indicate that lotic water features, including drainage infrastructure previously thought to be of minimal habitat value, contribute to habitat connectivity in this listed subspecies.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Landscape genetics identifies streams and drainage infrastructure as dispersal corridors for an endangered wetland bird
Series title Ecology and Evolution
DOI 10.1002/ece3.4296
Volume 8
Issue 16
Year Published 2018
Language English
Publisher Wiley
Contributing office(s) Alaska Science Center Biology WTEB
Description 16 p.
First page 8328
Last page 8343
Country United States
State Hawai`i
Other Geospatial O`ahu