An assessment of "turtle-friendly' lights on the sea-finding behaviour of loggerhead turtle hatchlings (Caretta caretta)

作者：Robertson Katharine; Booth David T^*; Limpus Colin J

来源：Wildlife Research, 2016, 43(1): 27-37.

DOI：10.1071/WR15138

• disorientation
• light pollution
• misorientation
• sea-turtle hatchling

Context It is well established that artificial light can disrupt the sea-finding ability of sea turtle hatchlings, and some manufactures are now marketing turtle-friendly' lights that are supposed to be minimally disruptive to this sea-finding behaviour. However, there have been no studies that have tested whether turtle-friendly' lights are benign to hatchling sea turtle sea-finding ability.
Aims We tested two different types of turtle-friendly' lights (LED amber-light peak intensity 620nm and LED red-light peak intensity 640nm) to see whether they are disruptive to the sea-finding ability of eastern-coast Australian loggerhead turtle hatchlings.
Methods Using standard circular-arena experiments, we assessed the directional preference of newly emerged loggerhead turtle hatchlings from the Woongarra Coast of Queensland, Australia, during different moon phases without artificial lighting and in the presence of turtle-friendly' lights.
Key results Contrary to expectations, sea-finding ability of hatchlings was disrupted by the amber lights, particularly in the absence of a moon. The less intense red lights were less disruptive to hatchlings; however, misorientation and disorientation events still occurred when lights were within 4m of hatchlings. The disruptive impact on sea-finding ability increased with the cumulative impact of multiple lights increasing light intensity.
Conclusions The turtle-friendly' lights we used disrupted the sea-finding ability of eastern-coast Australian loggerhead turtle hatchlings, with the most pronounced disruption occurring under moonless conditions.
Implications The use of amber and red LED lights adjacent to the nesting beaches of loggerhead sea turtles should be managed because this lighting has the potential to disrupt the sea-finding ability of sea turtle hatchlings.

• 出版日期2016