Hello!! Since I am currently studying Life sciences and planning on specialising in Environmental Biology, I am fairly interested in how light pollution affects wildlife and biodiversity! In todays’s blog post, I will be sharing briefly on how light pollution affects the loggerhead turtles!
The loggerhead turtles (Caretta caretta) are species of sea turtles that are known for their larger heads which contain powerful jaws to crush shelled prey. They usually have nesting sites on beaches in places such as Greece, Turkey and Israel (Loggerhead Turtle | Sea Turtles | Species | WWF, 2020). Unfortunately, besides the threats from plastic pollution and fishing, they also face problems from light pollution! These turtles display site-fidelity, meaning that they return to the sites that they hatched on and they lay their eggs there as well (Verutes, Huang, Estrella and Loyd, 2014). However, due to increase in urbanisation in coastal areas (tourist attractions, restaurants and housing), this has altered the nesting site landscape. Furthermore, these urban developments also introduces anthropogenic and artificial lights to these nesting sites. So what’s wrong with that?
With the drastic change in their nesting sites, female loggerhead turtles may be less likely to return to their original nesting sites and would instead go to other beaches with less favourable conditions (Verutes, Huang, Estrella and Loyd, 2014). Furthermore, for the turtles that do lay their eggs in these nesting sites, there may be further complications when their offspring hatch. Sea turtle hatchling in general are light-sensitive and they are visually dependent for them to navigate themselves to the ocean (Verutes, Huang, Estrella and Loyd, 2014). They use the reflection of the lights on the ocean from the moon and the stars to help them determine where the ocean is, where they have a better chance of survival. However, the artificial lighting from these anthropogenic sources disorientates the hatchlings. As mentioned previously as well, these anthropogenic sources usually make use of LED lights which emit blue light which has the shortest wavelength. Hatchlings will ‘preferentially orient’ to this shorter wavelength and higher energy light. This causes these hatchlings to move further in-land, away from the ocean and into human developments. Hence, these hatchlings may become road kill or they may simply die from dehydration or exhaustion (Verutes, Huang, Estrella and Loyd, 2014).
So what has been done? You can check out the video below to see measures that has been done to mitigate the effects of light pollution on sea turtles:
I hope this blog post does shed some light on the harmful effects of light pollution on sea turtles!!
References:
World Wildlife Fund. 2020. Loggerhead Turtle | Sea Turtles | Species | WWF. [online] Available at: <https://www.worldwildlife.org/species/loggerhead-turtle> [Accessed 14 October 2020].
Verutes, G., Huang, C., Estrella, R. and Loyd, K., 2014. Exploring scenarios of light pollution from coastal development reaching sea turtle nesting beaches near Cabo Pulmo, Mexico. Global Ecology and Conservation, [online] 2, pp.170-180. Available at: <https://www.sciencedirect.com/science/article/pii/S2351989414000274> [Accessed 14 October 2020].
Featured Image:
2019. Tourism Can Worsen Deadly Light Pollution In Sea Turtle Habitats. [image] Available at: <https://www.earth.com/news/tourism-light-pollution-sea-turtle/> [Accessed 14 October 2020].