Noise a global pollutant threatening over 100 animal species: Study

Human made noise must be considered as a "global pollutant" as it threatens the survival of more than 100 different animal species, including amphibians, birds, fish, mammals and reptilians, according to a study published on Wednesday.

The study, published in the journal Biology Letters, provides the first quantitative evidence for legislative bodies to regulate noise pollution more effectively. The World Health Organization (WHO) has said noise is one of the most hazardous forms of pollution, the researchers noted. However, the study found it does not just cause ill effects in humans, but on the biology and physiology of all animal groups studied: amphibians, arthropods, birds, fish, mammals, molluscs, and reptiles - terrestrial and aquatic.

The researchers from Queen's University Belfast in the UK suggest that noise pollution is affecting animals is the norm, not the exception. The study analysed the effects of noise in over one hundred species, which were divided into seven groups: amphibians, arthropods, birds, fish, mammals, molluscs and reptiles. "The study found clear evidence that noise pollution affects all of the seven groups of species and that the different groups did not differ in their response to noise," said Hansjoerg Kunc from Queen's University Belfast.

"Noise must be considered as a global pollutant and we need to develop strategies to protect animals from noise for their livelihoods," Kunc said in a statement. The research highlighted a number of threats caused by noise pollution to a range of species that could have implications for survival and population. The team noted that many species of amphibians, birds, insects and mammals communicate by producing acoustic signals. In doing so, individuals share vital information, e.g. on choosing a mate or warning family members of potential threats such as predators, the researchers explained. If noise pollution reduces the ability to communicate this vital information, it will have an impact on their survival.

While noise pollution prevents some animals escaping predators, conversely it can also inhibit some animals in their quest to find prey, the researchers said. Animals such as bats and owls rely on the sounds of the potential prey, they said. Noise pollution makes it more challenging to hear and, therefore, find their prey, forcing them to invest more time in sourcing food, which could lead to a decline in these species, the researchers said. In the aquatic world, fish larvae find their home based on the sound emitted by reefs. The researchers noted that increased noise pollution in the sea, mainly as a result of ships, makes it more difficult for fish larvae to find suitable reefs.

This means that many fish will choose less suitable reefs, which could reduce their lifespan. The researchers found that noise pollution also has a huge impact on the natural migration of animals. "This large scale quantitative study provides significant evidence that noise pollution must be considered as a serious form of man-made environmental change and pollution, illustrating how it affects so many aquatic and terrestrial species," Kunc said.