A Temporal and Spatial Analysis of Wedge-Tailed Shearwater (Ardenna pacifica) Fallout on Oahu
Loading...
Authors
Urmston, Jennifer L.
Issue Date
Type
Language
Keywords
Marine Science
Alternative Title
Abstract
Every year, hundreds of fledgling Wedge-tailed Shearwaters (Ardenna pacifica) are attracted to artificial light during their night-time voyage to sea, resulting in stranding and mortality from collisions and predation. I conducted a temporal and spatial analysis of fallout over an 8-year period during which highway streetlights were transitioned from unshielded high pressure sodium to shielded light-emitting diode lights. I used systematic road surveys at 3-day intervals to document road-killed shearwaters during November and December each year on southeast Oahu. I found that the change in highway lighting did not influence the magnitude of fallout, however an interaction between wind speed and moon illumination was a strong predictor. Likewise, the spatial distribution of fallout was not altered by the change in lighting, but the distance to the colony and maximum radiance were significant. My study showed no effect of the change in highway lighting on Wedge-tailed Shearwater fallout on southeast Oahu, suggesting that the new streetlights were neither better nor worse for the birds. The results of my study revealed that fallout occurs more frequently on nights with strong winds and low moon illumination and in brighter areas near the breeding colony. This new understanding of the timing and spatial distribution of fallout can be used to guide management of lighting and rescue efforts during the fallout season.
Description
Thesis
Citation
Publisher
Hawaii Pacific University