A recent study revealed that artificial nighttime lighting from offshore and shipping infrastructures, along with coastal communities, could be changing marine ecosystems.
Funded by the European Research Council, scientists used a floating raft along the Menai Strait in the UK to keep track of how artificial lighting at night influences the behavior of marine creatures along with their underwater habitats. The recent global development on light-emitting diode (LED) lighting is progressively illuminating the nighttime communities along the coastlines with white light. These white lights are affecting the larvae of sea creatures on their way to appropriate habitats for reproduction, feeding and settlement.
The scientists from Bangor and Exeter University discovered that white LED lighting can both delay and improve the colonization of sea creatures like the immobile sponge and coral reefs and other species frequent to most British shores, like keel worms and sea squirts. These light-attracted species can cause unwanted fouling of dockyards, marinas and aquaculture stations, but they can also provide significant ecosystem services for other species in the broader environment.
Coral larvae commonly utilize light to recognize optimal habitats to grow and settle in becoming reef building adult structures. Amphipod crustaceans like Corophium, commonly seen on mudflats, also tend to gather in areas lit up by the artificial white lights. Compared with tropical waters, white lights can penetrate UK waters more deeply and disturb a wider range of marine organisms.
"We know that artificial light at night alters the behavior of many marine animals but this is the first study to show that it can disrupt the development of ecological communities in the marine environment. Further research is urgently needed to assess what level of light can be considered 'safe' so that legislation can be put in place to minimize future light pollution from new and existing developments," Dr. Thomas W. Davies one of the authors of the study from the University of Exeter said.
The researchers warned that, as many marine invertebrates are excellent food sources for fish and other sea animals, the light pollution might affect the distribution of other, larger animals.
"With urbanization on the increase, many coastal areas around the globe will become vulnerable to the effects of artificial light pollution. Therefore, further research on how artificial light may disrupt marine communities is vital if we are to mitigate these impacts," Dr. Katherine M. Griffith, a co-author of the study and an ocean scientist at Bangor University, said.
The paper is published online in the Royal Society journal Biology Letters.
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