Year of Award
2024
Document Type
Dissertation
Degree Type
Doctor of Philosophy (PhD)
Degree Name
Wildlife Biology
Department or School/College
Wildlife Biology Program
Committee Chair
David E. Naugle
Commitee Members
Chad J. Bishop, Mark Hebblewhite, Kelsey G. Jensco, John S. Kimball, Johnnie N. Moore, Andrew C. Olsen
Keywords
waterbirds, wetlands
Abstract
In the arid and semi-arid western U.S., migratory waterbirds (e.g., shorebirds, wading birds, and waterfowl) rely on wetland landscapes that function as nodes in broader continental habitat networks (e.g., flyways). Here, I integrate citizen science and GPS animal tracking technologies with satellite imagery and cloud computing to quantify the effects of climate and land use change on wetland ecosystems that sustain migratory waterbirds in the western U.S. Four decades of wetland surface water hydrology were first reconstructed from over 150,000 individual satellite images covering 3.1 million ha to track monthly changes in the extent and duration of wetland inundation. Results were combined with eBird relative abundance data to identify emerging bottlenecks in flyway habitat networks. Assessments were made using an ensemble of shorebird and waterfowl species representing diverse life histories tied to wetland ecosystems within the study area. Lastly, movement data from 150 GPS-tagged white-faced ibis (Plegadis chihi, hereafter “ibis”) were used to link bird behavior to annually dynamic wetland trends and identify landscape compositions that structure breeding distributions. Long-term (1984-2023) wetland monitoring in the western U.S. showed that shortened inundation periods reduced semi-permanent wetlands by 24% and increased the combined abundance of seasonal and temporary wetlands by a nearly equal amount (23%). Semi-permanent losses were an early indicator of large-scale functional decline, signaling wetland transitions from persistent to more ephemeral states. Ubiquitous declines in half of the wetland systems predictive of shorebird, waterfowl, and ibis abundance were indicators of landscape drying that portend an irreversible and permanent shift in ecosystem water balance across North American waterbird flyways. Flyway conservation will require novel investments in our ability to monitor continental habitat change in concert with dynamic waterbird interactions. Combining waterbird movement data with publicly available satellite imagery and cloud-based computing platforms, demonstrated herein, can provide efficient solutions at a relatively low cost. Integrating these approaches into existing North American shorebird and waterfowl conservation initiatives can catalyze landscape protections for the sustainability of waterbird populations and wetland networks into the current century.
Recommended Citation
Donnelly, J. Patrick, "FLYWAY BOTTLENECKS: MIGRATORY WATERBIRDS CONFRONT DIMINISHING WETLAND NETWORKS IN WESTERN NORTH AMERICA" (2024). Graduate Student Theses, Dissertations, & Professional Papers. 12410.
https://scholarworks.umt.edu/etd/12410
© Copyright 2024 J. Patrick Donnelly