May 2008
The Early Bird Catches the Mate
a metropolitan nature phenomenon
It is three o’clock in the middle of the night. As silence prevails on the city streets, it seems like nothing is in the way of a good nights sleep, but suddenly birds erupt in raucous song. Those awakened by the tumult may wonder about the reasons for the vigorous chirping. Didn’t birds use to sing during the day and sleep at night just like humans? And why does a bird change its “natural” habit? Indeed, the phenomenon of birds that twitter during the night in January is a man-made phenomenon. As the noise level during a regular day in the city is very high, birds have given up on fighting against the city’s bustle and save their energy for nightly performances. Yet the birds are far from finicky divas. It is vital for birdsongs to be heard, as they are part of many birds’ mating processes. Another theory explaining the early performance of courting display proposes that the light pollution of the cities, together with a warm winter, jumbles the birds’ hormones. The creatures mistake the city lights and the warmer climate for the beginning of spring.
The explanations above are certainly grist to the mills of theorists who view cities as inhospitable to nature. Cities are deemed to be the most “unnatural” form of land-use, the result of a series of man-made actions. Originally, there was “true” wilderness without human beings, and in the end there were metropolitan communities. Such assertions, however, are based on the 19th- and early 20th-century slant, which deemed urbanity the agent of human alienation. While the philosophical question may still be of relevance, certain facts challenge this notion. The concept of untouched nature may still exist, but in reality, nature outside of urban areas in Central Europe is as cultivated and synthetic as it is within the cities. Quite contrary to commonly-held belief, cities harbor a multiplicity of animals and plants, while the widespread monoculture of the countryside leads to the thinning of biodiversity. In Munich—especially since the renaturation of the Isar and its shores—beavers, deer, foxes and badgers wander through the Isarauen to the city’s premises. By far, birds are the most widespread animals. These days, about as many avian creatures as human citizens live in Munich. While on the Bavarian countryside only 45 species can be distinguished, 116 different birds have chosen Munich as their home.
The city is attractive for many reasons: It offers sufficient nutrition, which can be found in wastebaskets, parks and from friendly hands. The city is also warmer than the hinterland. Birds have an intensive metabolism, which makes them almost independent from their circumstances. Lots of species live with a blood heat exceeding 40 degree Celsius, which enables them to adjust to extreme temperatures. The adjustment, however, costs a lot of energy and the warmer city area means the reduction of living expenses. We humans are also natural allies of birds. We keep the hunters away. Martens prefer not to live in human proximity, and hunters can’t operate within city limits. A magpie, for example, may be shot on the countryside, but can live safely in the city. Of foremost importance, however, is that Munich offers a diversified habitat. There are parks, the Isar river, garden ponds, skyscrapers, church towers and wasteland—something for each animal’s preference. Only the classic “city bird,” the sparrow, has a hard time surviving, since it used to breed in roof gutters that are no longer being built. In the meantime, however, the blackbird, which used to be a forest bird, has adjusted to city life. With 100,000 exemplars, the blackbird—followed by the great tit, the chaffinch and the greenfinch—represents the largest part of Munich’s bird population.
Even though they cannot be found in such high numbers, falcons also prefer city architecture for nesting. Church towers or the chimneys of power plants serve as breeding areas, and even a power pole can be converted into a hatchery. The adaptability of these creatures seems amazing, but once again, we often have a misinformed conception of how wild animals should behave. The densest population of larks, for example, can be found within the area of the Munich airport. The cut grass next to the runway has a texture similar to pasture land grazed by sheep—the perfect environment for larks! While we would not be able to cope with the constant noise, these creatures seem to be resistant to it. An explanation for this resistance can be found in nature itself, as deafening noise is a common natural phenomenon. Birds could not afford to panic just because of a clap of thunder. They quickly had to learn to distinguish between true dangers and mere loudness. The noise itself does not seem to bother the birds, which also sheds new light on the city birds’ shift of singing hours: There is nothing stressful about the traffic noise for them; it is just practical to avoid it in order to be heard.
While animals have long utilized urban surroundings as a vital habitat, it seems that we humans still think of cities as threatening or inferior to nature. With the ongoing debate over environmental protection, it is time to let go of out-dated conceptions and deal with the advantages and disadvantages of “citynature” on a realistic basis. In addition, the astonishing adaptability of some plants and animals should be a positive sign that the cohabitation of flora, fauna and humans is still possible. <<<
