21Over the last decades, growing human populations have led to the rising occupation of 22 coastal areas over the globe causing light pollution. For this reason, it is important to assess 23 how this impact threatens endangered wildlife. Leatherback turtles (Dermochelys coriacea) 24 face many threats of anthropogenic origin including light pollution on nesting beaches. 25However, little is known about the specific effects. In this study we studied the effect of 26 different light wavelengths (orange, red, blue, green, yellow and white lights) on hatchling 27 orientation under the presence and absence of moonlight by analyzing: (i) the mean angle of 28 orientation, (ii) crawling duration, and (iii) track patterns. 29Hatchling orientation towards the sea was always better under controlled conditions. 30In the absence of moonlight, leatherback hatchlings were phototaxically attracted to the 31 experimental focus of light (misoriented) for the colours blue, green, yellow and white lights. 32Orange and red lights caused a lower misorientation than other colors, and orange lights 33 produced the lowest disrupted orientation (disorientation). On nights when moonlight was 34 present, hatchlings were misorientated under blue and white artificial lights. Crawling 35 duration was low for misoriented hatchlings and high for the disoriented individuals. Our 36 conclusion to this is that hatchlings can detect and be impacted by a wide range of the light 37 spectrum and we recommend avoiding the presence of artificial lights on nesting beaches. 38Additionally, actions to control and mitigate artificial lighting are especially important during 39 dark nights when moonlight is absent.