Frogs failing to find love amid city din
The Age
Friday August 21, 2009
THEY like to do it froggy-style, but urban noise could be ruining the sex lives of Melbourne's frogs.Research by Melbourne University expert Dr Kirsten Parris has found that noise is drowning out the calls of Melbourne's frogs, reducing their chances of finding a mate.Speaking at a conference in Queensland, Dr Parris said frog calls were a crucial part of finding sex, but many of Melbourne's frogs were now soliciting to a much-reduced geographic range.The audible range of the southern brown tree frog was found to be reduced from around 75 metres to about 20 metres in city conditions, while noise spill had reduced the calling range of the pobblebonk frog (pictured) by several hundred metres."Being heard is important," she said. "If the females can't hear them, then perhaps their chances of breeding are lowered."Frogs with low-frequency calls were particularly affected, given most urban noise €” from traffic to air conditioners €” produced a low rumble.Dr Parris said the southern brown tree frog had been observed adapting to this problem with squeakier and higher-pitched calls.After monitoring 50 sites around Melbourne, Dr Parris said Kew Billabong in the inner-eastern suburbs might be the worst place for amorous frogs to try their luck, due largely to the nearby Eastern Freeway.More peaceful places for frogs to make sweet music were found near Mount Macedon and the far-eastern suburbs, such as Belgrave.
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