He added that the team did find that the presence of lower frequency elements in a song was predictive of whether a species' abundance would be affected by noise.

BBC: Traffic noise driving songbirds to the limit in cities

In the paper, the scientists concluded that difference in abundance and species richness in the damaged areas was probably a result of engineering by elephants, generating new habitats for a diverse array of frog species.

BBC: Elephant ecological engineering 'benefits amphibians'

These groups have employed a strategy of attempting to overwhelm the USFW with proposals to list hundreds of plant and animal species that exist in abundance over large geographic areas that are home to oil and gas exploration, wind farm development, major solar installations, highway projects and other significant human development projects.

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He suggested that females may perceive the song as abnormal if they could not hear the lower frequencies and, over a period of time, this could have a potential impact on the abundance of the species as if adults were not pairing and mating then the number of offspring would decrease as a result.

BBC: Traffic noise driving songbirds to the limit in cities

The WCBS, which began in 2009, complements other national butterfly surveys - such as the UK Butterfly Monitoring Scheme - and aims to "more effectively monitor the changing abundance of widespread butterfly species across the general countryside".

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What is more, the extent of sea ice cover influences the abundance of krill and the fish species that eat them - both food sources for the penguins.

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He said that the study also focused on seven species that did inhabit the area to see if their abundance was affected as the urban noise increased.

BBC: Traffic noise driving songbirds to the limit in cities