Institute of Marine Sciences - OKEANOS, University of the Azores, Rua Professor Doutor Frederico Machado 4, 9901-862 Horta, Portugal.
Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, 10257 Vilnius, Lithuania.
J Exp Biol. 2023 Apr 1;226(7). doi: 10.1242/jeb.245126. Epub 2023 Apr 12.
Light pollution critically affects fledglings of burrow-nesting seabirds, leading to massive mortality events. The successful management of this pollutant depends upon a comprehensive understanding of the factors influencing visual sensitivity and corresponding behaviours towards light. Factors shaping the development of the visual system could account for variation in seabirds' vulnerability to light pollution. We investigated how Cory's shearwater chicks respond to selected contrasting artificial light stimuli. Chicks were subjected to blue and red light treatments, and repeatedly tested throughout the nestling period. We analysed behavioural responses (number, timing and orientation of reactions) to determine how age, exposure to experimental light stimuli and spectra influenced the onset of visually guided behaviours, thus inferring drivers of vulnerability to light pollution. Repetitive exposure to light significantly increased the number of reactions, and chicks predominantly displayed light avoidance behaviour. We did not find differences in the number of reactions, timing and orientation between blue and red light treatments. The responses did not differ across different age groups. These results provide empirical evidence for the contribution of the light available in the rearing environment to seabird visual development. They support the hypothesis that differential exposure to light during the growth period influences responses to artificial light, and that the state of visual development at fledging could be a main driver of the age bias observed during seabird fallout events. It is thus important to evaluate lighting schemes in both urban and natural areas, and determine the as yet unknown consequences that may be affecting the populations.
光污染严重影响穴居海鸟的雏鸟，导致大量死亡事件。这种污染物的成功管理取决于对影响视觉敏感性和对光的相应行为的因素的全面了解。影响视觉系统发育的因素可以解释海鸟对光污染的脆弱性差异。我们研究了冠毛小海雀雏鸟对选定的对比人工光刺激的反应。雏鸟接受蓝光和红光处理，并在整个育雏期反复进行测试。我们分析了行为反应（反应的数量、时间和方向），以确定年龄、暴露于实验光刺激和光谱如何影响视觉引导行为的开始，从而推断出对光污染脆弱性的驱动因素。重复暴露于光线下会显著增加反应次数，雏鸟主要表现出避光行为。我们没有发现蓝光和红光处理之间在反应数量、时间和方向上的差异。不同年龄组之间的反应没有差异。这些结果为育雏环境中可用光对海鸟视觉发育的贡献提供了经验证据。它们支持这样一种假设，即生长期间对光的不同暴露会影响对人工光的反应，并且在出飞时的视觉发育状态可能是海鸟坠落事件中观察到的年龄偏差的主要驱动因素。因此，评估城市和自然区域的照明方案，并确定可能影响种群的未知后果非常重要。
