City birds sleep less than their country counterparts
Living in the city it seems is as stressful for birds as it is for humans. A new study shows that there were key differences in the daily routines of birds living in the city and birds living in the countryside.
A study carried out by British and German researchers used six blackbirds in the centre of the German city Munich and six in a woodlands area about 25 miles away. The bird's actions and behaviours were monitored for a week. The most surprising findings were that city birds wake up around 30 minutes before dawn while birds in the forest wake up as the sun rises.
The study was carried out by the University of Glasgow in UK and the Max Planck Institute for Ornithology in Germany.
Other research found that the internal clocks of urban birds were ticking faster which could leave them in an agitated and jetlag like state. Another interesting observation is that the birds from the Munich business district, a more brightly lit area, had more disruptive lives than their counterparts elsewhere in the city.
Commenting on the findings Barbara Helm, of the University of Glasgow's Institute of Biodiversity Animal Health and Comparative Medicine said: "The daily cycles of activity and rest are based on biological rhythms which have evolved as an adaptation to the rising and setting of the Sun,"
"Our tests were designed to benchmark the internal rhythms of the birds under controlled conditions and to determine a link to the birds' chronotype in the wild.
"Chronotype is a measure of an individual's consistent timing relative to environmental factors, ie, its relative 'morningness' or 'eveningness'.
It is well known that health problems are prevalent with altered sleep patterns amongst humans such as obesity to breast cancer. The researchers now want to look closer into the effect the changes in sleep have on the bird population. One thing already is known though about early risers. One positive aspect is that by being awake earlier in the morning then they are more likely to find a mate.
Now researchers will take a look at other animals that live in the city such as urban foxes and see the health implications. With research like this, researchers may be able to develop ideas as to the effect of light on people with sleeping disorders and come up with methods to help them sleep better.
Birds have developed to city life in many ways. In San Francisco, sparrow’s songs have become more developed so that they can be heard above the traffic. The high pitch allows them to reach further away to reach more potential mates. Robins in Sheffield have abandoned their songs in the morning and now sing at night.