Turning the street lights off decreased the number of grounded fledglings, according to a study published October 15, 2014 in the open-access journal PLOS ONE by Airam Rodríguez and colleagues from Phillip Island Nature Parks, in Victoria, Australia, and Estación Biológica de Doñana, in Spain.
Thousands of birds are attracted to lights–sometimes referred to as light-pollution–every year worldwide during their first flights from their nests to the open ocean, a phenomenon called 'fallout.' Short-tailed shearwater breeding on the coast of Australia are also affected when fledgling chicks leave their nest about a month after their parents. In an effort to understand the magnitude of 'fallout,' the authors of this study have reported the number of fledging short-tailed shearwaters found grounded during evening and morning rescue patrols conducted at Phillip Island, Australia, during a 15-year period (1999-2013). Additionally, they assessed factors affecting numbers of grounded birds and mortality including date, moon phase, wind direction and speed, number of visitors, and holiday periods and tested whether turning lights off could make an impact on the number of birds found on the ground.
Over 8800 fledglings were found during the 15-year study period and almost 40% were dead or dying. This mortality rate was 4-8 times higher than reported elsewhere, at sites where searching for fledglings was more opportunistic rescue rather than regular patrols, indicating that mortality numbers may be underestimated in other locations. The researchers found more grounded birds in peak fledging, moonless, and windy nights. Mortality increased through the fledging period, in the mornings, and with increased traffic on holiday periods, but turning the road lights off decreased the number of grounded birds. While researchers could not control for the moon and wind, they suggest that reduction of light pollution and better traffic management might help mitigate artificial light-induced fledgling mortality.
In your coverage please use this URL to provide access to the freely available paper: http://dx.plos.org/10.1371/journal.pone.0110114
Citation: Rodríguez A, Burgan G, Dann P, Jessop R, Negro JJ, et al. (2014) Fatal Attraction of Short-Tailed Shearwaters to Artificial Lights. PLoS ONE 9(10): e110114. doi:10.1371/journal.pone.0110114
Funding: AR was supported by a Marie Curie International Outgoing Fellowship within the 7th European Community Framework Programme (n 330655 FP7PEOPLE-2012-IOF). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing Interests: One of the authors (André Chiaradia) currently serves as an Academic Editor or Guest Editor for this journal. Please note that this does not alter the authors' adherence to PLOS ONE Editorial policies and criteria.