Once part of the urban horizon, crows are leaving Iranian cities.
Since the 1980s scholars have studied the influences of urbanization on the environment, particularly the ecosystem. The rapid growth of the urban population and especially the lifestyle of the urban dwellers have undeniable effects on the life of living species and plants. Birds are of the animals that are completely affected by urbanization. Among several studies that have been done on the effects of the urban life on ecosystem, some are on the influences on the life of urban birds. Such studies show how urbanization modifies the life of avian communities of the cities by influencing food, water, climate, and predators.
During the past years, the lives of urban birds of the Iranian cities have been monitored by activists. This was started when reports of fleeing birds of Tehran were given out. While many believe that the birds of Tehran are really less than before, some say that the birds just move from the regions with higher pollution to the less-polluted parts. So the population of birds in some regions is even more than before.
Example of such studies, which is accessible online is a paper written by Beissinger and Osborne in 1982: “Effects of Urbanization on Avian Community Organization”.
Another online document that is worth reading is “Effects of Urbanization on Bird Populations in the Canadian Central Arctic” written by Richard J. Staniforth.
The story of migration of birds from cities is not limited to Tehran. Recently with the increase of air pollution in Esfahan, new reports about decreasing number of birds have been published. The last kind of birds, which are affected by air pollution, are crows. These birds are more resistant against hard conditions than many other types of birds, but still are escaping from the polluted urban environment of Esfahan. Previously the city was famous for its high number of crows.
Apart from air pollutions some other factors are important in the present condition of the urban birds of cities like Esfahan. The growing urbanization has had bad effects on the habitat of the birds, for example a large number of the trees of Esfahan are in bad conditions because of air pollution. So the birds are forced to move out of the city. Many of them are good food for the birds of prey or other animals of outside the cities. So they are also in danger of extinction.
Years ago “birds in the alleys” was quite a normal and usual picture that every one could imagine of their living space. Now it is obviously necessary to do something to save the urban environment. The question is what?
More articles on the environmental problems of Iran:
High Waste Generation and Low Level Recycling in Iran
NGOs Tell It On the Mountains in Iran (Clean Up!)
Record Hot Summer Ignites Forest Fires in Iran
Image by Hamid Reza Mohammadi
