If half of the green space in a city is covered with concrete, the number of young birds flying out of the nesting boxes in that area will be halved, scientists from the University of Warsaw have shown. The results of their study also provide precise data that can be used by decision-makers.
'We finally have hard data that confirm our earlier observations that the more concrete, the smaller the bird brood in the city. This is a pioneering study of this type in Central and Eastern Europe', says Professor Marta Szulkin from the University of Warsaw, who has been dealing with this topic for a decade.
The paper on this subject has just been published in the journal Conservation Letters. The first author is Szulkin's former doctoral candidate, Michela Corsini, PhD. Many students were also involved in the research project, the University of Warsaw press office reports.
The researchers have calculated how introducing impermeable surfaces (concrete or asphalt) within a radius of 100 meters from the nest (or nesting box) affects the number of young birds that fly out into the world: great tits and blue tits, species well adapted to life in the city.
And so, if half of the green space is concreted, the number of young birds flying out of the nesting boxes is reduced by half. This means that the breeding success of urban birds is reduced by half.
The authors of the publication also show how to calculate it precisely. 'In the face of rapid urbanization, cities need hard data to support decisions on shaping the green infrastructure. Our publication provides data for city planners, landscape architects and political decision-makers that will help in the development of space', Szulkin says.
The authors of the publication used data from five years. 'But our research is really the culmination of 10 years of my work in Poland. During this time, we have created a system of 500 nesting boxes in Warsaw and its immediate surroundings', says Professor Marta Szulkin.
The boxes were placed not only in parks, but also in housing estates (including Olszynka Grochowska and Muranów), in a cemetery and in urban and suburban forests. The boxes were also placed on the Ochota Campus of the University of Warsaw.
Then, every year, scientists observed the birds for several weeks from early spring.
The publication presents precise estimates for two species of tits that are common in cities: great tits and blue tits. 'The results can also be applied to other birds, although species that are more sensitive to living conditions probably have even greater breeding problems', Szulkin believes.
'I would like the results of our research and the data we show to serve as guidelines in the context of revitalizing green areas, as well as for urban planners, architects and managers of urban greenery. Of course, we cannot have cities without concrete, but there are many places where its amount can be reduced', the scientist says.
She added that the research was conducted in Warsaw, but its results can be applied to other cities - both larger and smaller ones. (PAP)
PAP - Science in Poland
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