This article was originally published on The Conversation. The book donated the article to Space.com Soundtracks: Op-Ed & Insights.
Svenja TidauPostdoctoral Researcher in Marine Biology, Plymouth University
Daniela Torres DiazMoho PhD in Biology, Aberystwyth University
Stuart JenkinsProfessor of Marine Ecology, Bangor University
Many nocturnal animals use light from the moon and stars to move at night in search of food, shelter, or companions. But in our further research we found out how artificial lighting works during these movements at night.
Electric lights are changing our world. About 80% of the world’s population lives in areas where the sky is polluted by artificial light. A third of humanity can no longer see the Milky Way – the galaxy for our solar system. But the effect of light at night is much more profound. In humans, light pollution at night has been linked to sleep disorders, obesity, obesity and certain types of cancer.
Studies have shown that nocturnal animals change their behavior with small changes in the light levels of the night. Dirt animals are in trouble when navigating lands if the stars cannot be seen by light pollution. Light can change the way we interact with each other. Moths are more likely to be eaten by bats when the light reduces their ability to protect against thieves.
Read more: Scientists have learned how cattle use the Milky Way to block their path
Little is known about the nature of marine life and beaches. Clownfish exposed to light pollution cannot produce well, as they need darkness for their eggs to flower. Other fish thrive at night when there is plenty of light, come out of their hiding places quickly in the daytime and increase their visibility of thieves. These effects are seen under natural light from beaches, cruises, boats and ports, which means that the impact of light pollution on night marine life is thought to be minimal.
Otherwise, when the light is emitted from the street lights above, it will be scattered in the sky and can be seen again on the ground. People outside the countryside at night will see this effect as a flash of light over a distant city or town. This type of light pollution is known as artificial skyglow, and is about 100 times dimmer than that from direct light, but is more common. It can now be seen over a quarter of the world’s coastline, from where it can extend hundreds of miles out to sea.
It is not easy for people to see at night, so the effect of the skyglow is not visible. But marine and beach creatures are more sensitive to low light. Skyglow can change the way they see the night sky, and in turn, affect their lives.
Crustaceans in the light
We tried this idea using a little sand (Talitrus saltator), a beach crustacean that has been known to use the moon to guide its nightly dining journey. Less than an inch long, sand dunes are often seen on the sandy beaches of Europe and are named for their ability to fly several inches in the air.
They plant in the sand during the day and go out to eat rotten limu at night. They play an important role in their ecosystem by breaking down and recycling food from stranded animals. If you pick up washed seaweed on an evening beach walk, you won’t have a problem finding them.
In our study, we reproduced the effects of artificial skyglow by using a white LED light in a wide headlight to cast a piece of light and black on the beach between 19 nights between June and September 2019. On light nights with full moon, sand. hoppers actually move to the beach where they encounter algae. Under our skyglow, they move much easier.
They are often less mobile, with no feeding opportunities, because of their role as new users, which can have far -reaching effects on the ecosystem.
The artificial skyglow changes the way a sand hopper is used on the moon to navigate. However, the use of the moon and stars as compasses is common among various marine and terrestrial animals, such as seals, birds, reptiles, amphibians and insects, more and more living things are at risk in the sky. And there is evidence that the Earth is much brighter at night. From 2012 to 2016, scientists found that the world’s illuminated outer areas increased by 2.2% each year.
As researchers, we hope to unravel the nature of light pollution affecting marine and marine ecosystems, by looking at the impact on the development of different animals, the relationship between between characteristics and effects at the molecular level. Only by understanding if, when and how light pollution affects night life can we find ways to reduce the impact.
This article is republished under The Conversation under a Creative Commons license. Read the original article.
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