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Providing evidence to improve practice

Individual study: Shielding of security lights reduces numbers of grounded Newell's shearwaters Puffinus newelli at Lihue, Kauai, Hawaii, USA

Published source details

Reed J.R., Sincock J.L. & Hailman J.P. (1985) Light attraction in endangered procellariiform birds: reduction by shielding upward radiation. The Auk, 102, 377-383


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Shield lights to reduce mortality from artificial lights Bird Conservation

A replicated, controlled study at a resort on Hawaii, USA, in 1980 and 1981 (Reed et al. 1985), found that significantly fewer Newell’s shearwaters Puffinus newelli were found grounded under security lights on nights when twelve of the brightest lights had ‘hoods’ placed on them, compared to alternate nights when lights were not shielded (272 birds on 32 ‘shielded’ nights vs. 444 birds on 32 control nights). The reduction was greater in 1981 (52%) than 1980 (29%), possibly because peak shearwater fledging coincided with a full moon (and so higher ambient light) in 1980, but with a new moon in 1981. The shields reduced upwards radiation of light and during the experiment most other lights on the resort were permanently shielded.