Sixty years (1960-2019) of urban ornithology in Spain: bibliometrical analysis of a work in progress

This paper analyses the research conducted on bird fauna inhabiting Spanish urban environments between 1960 and 2019. At least 183 papers were published in that period, 80% in the last 20 years. Most of the research topics show an increase along time, being ecology and ethology the most investigated of them; most of the ecology papers deal with landscape ecology/biogeography. About half of the papers were devoted to bird assemblages, in the remaining ones, 42% was focused on just 8 species, being the Common Sparrow Passer domesticus, European Blackbird Turdus merula and Great Tit Penis major the three most studied species. Research effort was unevenly distributed across Spanish regions in such a way that 68% of the studies were conducted in only 5 large or mid-size towns. Several of the patterns and trends reported are coincident with international research on urban bird fauna; there are also differences like the emphasis on the research of urban park's bird fauna and, conversely the little interest aroused by bird response to levels and models of urbanization, and the relationship between urban birds and socioeconomic factors. Paradoxically in a country where urbanization has been widespread and persistent over the last 60 years, the effects of this extreme form of landscape conversion albeit have been studied. It is concluded that this aspect along with research on urban bird biology over long time periods, will be crucial to modulate urban development for bird conservation purpose