Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Light is the friend of lovers: Artificial night lighting affects songbird behaviour and reproduction

17.09.2010
The increase of artificial night lighting is one of the consequences of intense urbanization. To date, however, the consequences of light pollution on wild populations of animals have not received enough attention.

Scientists of the Max Planck Institute for Ornithology have now shown that permanent night lighting alters the reproductive behaviour of birds. In those habitats that are affected by artificial light males started to sing earlier and females advanced the onset of breeding activities. Moreover, males occupying territories with street lights had a higher number of extra-pair mates than males living in the dark forest.

Artificial light at night has fatal consequences for many nocturnal animals. Millions of insects, for example, die each year through the attraction to street lamps. Migratory birds get distracted by artificial night light, and consequently, go astray and even crash into illuminated high-rise buildings. Although artificial light has not always such fatal impact, it nevertheless can have a substantial influence on an animal’s life. This problem was investigated by Bart Kempenaers and colleagues from the Max Planck Institute for Ornithology in Seewiesen in five species of songbirds. They studied the effect of street lighting at the outskirts of forest habitat on the song behaviour of male birds. Indeed, males from four out of five species started to sing earlier in the morning than males that lived in locations without artificial night light. This effect was most pronounced for those species known to engage in early dawn singing. For example, male robins living near street lights started singing on average 80 minutes earlier than their conspecifics sleeping in the dark.

The researchers were not only interested in the relationship between night lighting and song behaviour but also whether artificial light explicitly influenced the bird’s reproductive behaviour. Over seven consecutive years they monitored breeding activities in a population of blue tits. Those females that lived near artificial light started egg-laying on average one and a half days earlier than females in territories without street lights or in central forest territories. “Females that start to lay earlier usually produce more eggs. They are often in a better physical condition than those that start laying later in the season”, explains Bart Kempenaers, director in Seewiesen. “However, females that advance breeding due to the artificial light do not, overall, lay more eggs”. Earlier egg laying could be disadvantageous for the offspring if they hatch outside the peak of food availability.

Light influences the number of extra-pair partners with whom males sire offspring

Artificial night lighting had a strong effect on the reproductive success of male blue tits: The scientists found that males living in forest outskirts exposed to street lights were twice as successful in obtaining extra-pair mates than their neighbours in the darker areas within the forest. This effect was most pronounced in yearling males that are usually not very successful in siring extra-pair offspring. Under the influence of artificial light, those males sired almost as many extra-pair offspring as older males in dark habitats. “Most likely early dawn song represents a signal for the females to estimate male quality”, argues Bart Kempenaers. Thus, light pollution potentially leads to maladaptive mate-choice decisions in relation to the quality of extra-pair partners. However, whether the early singing, the early egg laying and the altered extra-pair mating behaviour have consequences for survival and fitness of the adults and their offspring remains to be investigated.

Original work:
Bart Kempenaers, Pernilla Borgström, Peter Loës, Emmi Schlicht and Mihai Valcu
Artificial night lighting affects dawn song, extra-pair siring success and lay date in songbirds

Current Biology, published online September 16th, 2010

Dr. Sabine Spehn | Max-Planck-Institut
Further information:
http://www.orn.mpg.de

More articles from Life Sciences:

nachricht Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>