Hawaiian waterbird movement across a developed landscape

Abstract

A key component for biologists managing mobile species is understanding where and when a species occurs at different locations and scaling management to fit the spatial and temporal patterns of movement. We established an automated radio‐telemetry tracking network to document multi‐year movement in 2016–2018 of 3 endangered waterbirds among wetlands on Oʻahu, Hawaiʻi, USA: ʻalae ʻula or Hawaiian gallinule (gallinule; Gallinula galeata sandvicensis), ʻalae keʻokeʻo or Hawaiian coot (coot; Fulica alai), and aeʻo or Hawaiian stilt (stilt; Himantopus mexicanus knudseni), each with different ecological requirements. There were marked differences in the movement propensity of the species, with no movement among sites detected in gallinules, 31% of coots moving among wetlands, and very high levels of daily movement in stilts. A network analysis revealed strong evidence for fidelity among individual stilts to specific wetlands, indicating different groups of wetlands supported different birds. There was also strong evidence for patterns in daily and seasonal movement patterns of stilts. Our work indicates the importance of each wetland to the waterbirds they support, as each individual had strong fidelity to a single wetland. In addition, for Hawaiian coots and stilts, which were documented moving among multiple wetlands, a network of wetlands may be key for long‐term persistence of these endangered species, and coordinated regional management of waterbirds as a shared resource could provide greater benefits to waterbirds than independent management of each wetland.