Thursday, January 6, 2011

Do birds & frogs sing differently in the city?

Wildlife can use sound to communicate in many different ways but, more often than not, they may distinctive sounds to help find a mate. One of the things I've notice while recording in urban wetlands is the large amount of noise pollution caused by traffic, industry and other human activity. I know there is a dramatic reduction in frog calling activity during evenings when the wind is strong. One field trip on the south coast we recorded about 8 species of frog calling on the first night but one the second night the wind was much stronger and we only recorded 2 frog species. How are these animals responding to "human-made" noise?

There has been some media interesting in a recent Melbourne University study that has indicated that urban noise is changing the calls of some bird species. The soon to be published study titled "Geographically pervasive effects of urban noise on frequency and syllable rate of songs and calls in silvereyes (Zosterops lateralis)" by Potvin, Parris & Mulder reports on the adaptation of birds to urban environments by calling at higher frequencies. You can read the abstract here.

It also reminded me of this paper reporting a change in the frequency of frog calls in habitats close to traffic from 2009. That paper reporting on changes in frog calls, "Frogs Call at a Higher Pitch in Traffic Noise" by Parris, Velik-Lord & North is available here Turns out it is one of the same researchers, K Parris, involved in both projects!

I guess what the work of these researchers is showing is that our natural environment can be influenced as much, perhaps, by noise pollution as other forms of pollution. While bird calls may be shifting as a result of learnt behaviours, the change in frogs call may be reflecting an evolutionary shift in animals adapted to urban environments. I'll be keen to follow the continuing work of Parris and her collegues.


Meroo National Park Management Plan

In December 2010, The Department of Environment, Climate Change & Water released the Meroo National Park Plan of Management. Below is the press release announcing the adoption of the plan:

The recent adoption of the Plan of Management for Meroo National Park ensures the protection of the park's significant cultural and natural environment values while providing for unique visitor experiences.

The National Parks and Wildlife Service (NPWS) South Coast Regional Manager, Ms Diane Garrood said extensive community consultation was undertaken in preparing the plan of management for the park.

"A community working group was established to assist the NPWS to prepare a draft plan," Ms Garrood said.

"The draft plan was then publicly exhibited to obtain further community input and discussions have been held on specific issues such as vehicle access to Meroo Lake."

Meroo National Park, located 5 kilometres south of Ulladulla, includes almost 4,000 hectares of high conservation value coastal forests and lake ecosystems.

It also contains the former Barnunj State Conservation Area which has now been declared part of the park. The bed of Meroo Lake is to be added to the park early next year.

"The park is of national significance for its biological and landscape values. It is home to many threatened fauna including the nationally endangered Green and Golden Bell Frog," she said.

"The plan seeks to protect these important values while continuing to provide for public enjoyment through activities such as camping, bushwalking, kayaking and fishing.

"The combination of the relatively undisturbed coastline and coastal lakes in a forested setting provides visitors with wonderful, unique experiences."

A copy of the plan can be found on the DECCW website at or printed copies obtained by contacting the NPWS South Coast Regional office at Nowra on ph: (02) 4423 2170.

The plan highlights many of the difficulties in managing coastal environments in NSW where a balance must be met between environmental conservation and recreational activities. For more information, as well as links to download the management plan, please visit the DECC website