Featured Research

from universities, journals, and other organizations

Clamorous city blackbirds: Birds can sing louder at higher frequencies to make themselves heard over traffic noise

Date:
January 11, 2013
Source:
Max-Planck-Gesellschaft
Summary:
Birds can sing louder at higher frequencies and thereby make themselves heard over traffic noise.

Blackbirds also find an abundant food supply in the city.
Credit: Michael Dvorak

Animals have developed a variety of strategies for dealing with increasing noise pollution in their habitats. It is known, for example, that many urban birds sing at a high pitch to differentiate their song from the low-frequency sound of road traffic. However, as scientists from the Max Planck Institute for Ornithology discovered, this is just a useful side effect. The real reason for this behaviour is that songs at a higher pitch are also automatically louder. The birds can make themselves heard far better in city noise by increasing the volume of their song than by raising its frequency.

Despite the numerous unfavourable environmental conditions they encounter there, many wild animals have colonised cities as a new habitat. In cities they must deal with greater numbers of humans and with more light and noise pollution than they encounter in rural settings. However, the urban habitat also offers certain advantages, for example a more abundant supply of food and new breeding options. Many animals have thus adapted surprisingly well to city life.

To attract mating partners and defend their territories, urban robins sing in the latter night when the traffic noise decreases after the evening rush. Many other bird species, including blackbirds, sing in urban environments at a higher pitch. So their song is easier to detect in the lower-frequency traffic noise.

However, as a group of scientists from the Max Planck Institute for Ornithology in Seewiesen and Radolfzell has discovered, this is just half the truth. They studied urban blackbirds in the city of Vienna and country blackbirds in the nearby Vienna Woods. Additionally, they raised birds by hand at the Max Planck Institute and investigated the correlations between the frequency and amplitude of their song under controlled conditions. It emerged from this research that the animals were able to produce higher tones at higher amplitudes. In the city, blackbirds sing preferably at these high frequencies that they can produce particularly loudly.

In a further step, the researchers examined which effect is better suited to avoiding the acoustic masking by traffic noise: the higher frequency or the higher amplitude that results from it. "The higher volume of the higher-pitched song is more effective than the higher frequency," says Erwin Nemeth, first author of the study. "So we assume that the increased volume is the main cause of the higher frequency singing by city birds." Henrik Brumm, the leader of the research team, adds: "By actively selecting high-frequency sounds, the city birds can increase their capacity to sing loudly and in this way counteract the acoustic masking of their song by the ambient noise."


Story Source:

The above story is based on materials provided by Max-Planck-Gesellschaft. Note: Materials may be edited for content and length.


Journal Reference:

  1. E. Nemeth, N. Pieretti, S. A. Zollinger, N. Geberzahn, J. Partecke, A. C. Miranda, H. Brumm. Bird song and anthropogenic noise: vocal constraints may explain why birds sing higher-frequency songs in cities. Proceedings of the Royal Society B: Biological Sciences, 2013; 280 (1754): 20122798 DOI: 10.1098/rspb.2012.2798

Cite This Page:

Max-Planck-Gesellschaft. "Clamorous city blackbirds: Birds can sing louder at higher frequencies to make themselves heard over traffic noise." ScienceDaily. ScienceDaily, 11 January 2013. <www.sciencedaily.com/releases/2013/01/130111110916.htm>.
Max-Planck-Gesellschaft. (2013, January 11). Clamorous city blackbirds: Birds can sing louder at higher frequencies to make themselves heard over traffic noise. ScienceDaily. Retrieved August 29, 2014 from www.sciencedaily.com/releases/2013/01/130111110916.htm
Max-Planck-Gesellschaft. "Clamorous city blackbirds: Birds can sing louder at higher frequencies to make themselves heard over traffic noise." ScienceDaily. www.sciencedaily.com/releases/2013/01/130111110916.htm (accessed August 29, 2014).

Share This




More Earth & Climate News

Friday, August 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Killer Amoeba Found in Louisiana Water System

Killer Amoeba Found in Louisiana Water System

AP (Aug. 28, 2014) State health officials say testing has confirmed the presence of a killer amoeba in a water system serving three St. John the Baptist Parish towns. (Aug. 28) Video provided by AP
Powered by NewsLook.com
Scientists Have Figured Out Why Rocks Move In Death Valley

Scientists Have Figured Out Why Rocks Move In Death Valley

Newsy (Aug. 28, 2014) The mystery of the moving rocks in Death Valley, California, has finally been solved. Scientists are pointing to a combo of water, ice and wind. Video provided by Newsy
Powered by NewsLook.com
Big Waves, Minor Flooding from Hurricane

Big Waves, Minor Flooding from Hurricane

AP (Aug. 27, 2014) Thundering surf spawned by Hurricane Marie pounded the Southern California coast Wednesday, causing minor flooding in a low-lying beach town. High surf warnings were posted for Los Angeles County south through Orange County. (Aug. 27) Video provided by AP
Powered by NewsLook.com
Calif. Quake Underscores Need for Early Warning

Calif. Quake Underscores Need for Early Warning

AP (Aug. 26, 2014) Researchers at UC Berkeley are testing a prototype of an earthquake early warning system that California is pursuing years after places like Mexico and Japan already have them up and running. (August 26) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins