09/3/09

Urban Frogs' Love Calls Go Unanswered in Australia

Kirsten Parris, an Australian ecologist, has discovered that noise of traffic and machinery may be contributing to the decline of frogs in Melbourne.

Female frogs are attracted to male frogs that have the loudest calls. But what if they can’t hear them calling due to all the noise? Frogs have adapted—they are expending more energy to make their croaks louder, using higher pitches to drown out the lower frequency traffic. But frogs with low-pitched croaks are at a disadvantage. According to this article in Eco-Wordly, “Without the noise of the traffic and machinery, pobblebonk frogs can be heard by females at distances up to 875 yards. But add in some traffic and other noise, and the distance is reduced to only 46 feet!”

Living in a city, I’m all for reducing noise. Just today, I heard a jackhammer, a loud droning drill next door, police sirens, not to mention the sounds of cars, trucks, and planes. The question is, how can this noise be reduced? Any ideas? Perhaps during the frog mating season, people could be a little quieter! (Not an issue in our city however. No frogs here!)

The Pobbledonk or Banjo frog is named for its distinctive "bonk" call, which sounds like a banjo string being plucked. Photo by Donna Flynn

The Pobblebonk or Banjo frog is named for its distinctive "bonk" call, which sounds like a banjo string being plucked. Photo by Donna Flynn

To learn more about Aussie frogs, check out the Frogs Australia Network.