Pre-Symposium organized by the European Ornithologist Union

Co-Conveners: Juan Diego Ibáñez-Álamo, Mark Mainwaring, James Reynolds and Petra Sumasgutner


Half-day (6 ×15-min time slots for talks; 1.5 h for round table discussions).

Symposium description

Despite the rapid global transformation of natural landscapes into urban environments, we still lack a clear understanding of how urbanization impacts ecological interactions and evolutionary processes. Globally more people live in urban than in rural areas, and by 2050, 66% of the world’s population is projected to be urban. These towns and cities present wild birds with a variety of novel stressors, arising from alteration of biotic interactions (e.g. host-parasite and predator-prey interactions), anthropogenic disturbance, pollution (from electromagnetic radiation, light, air, chemicals and noise), habitat loss and fragmentation, as well as changes in food quality and availability. Urbanization affects organisms directly (e.g. via ecophysiological constraints), and indirectly by disrupting trophic interactions in multi-species networks. Changes in behavior, physiology and life history of birds inhabiting urban inhabitants have all been widely documented.

A key challenge is to understand the mechanisms underlying this environmentally-induced variation and, in turn, to understand the capacity for birds to be able to cope with, or adapt to, novel selection pressures in urban environments. While some species are able to thrive in urban environments and profit from food and/or nests-site availability, others are much less tolerant and may be displaced. A greater understanding of the causes and consequences of exposure to urban stressors is therefore necessary to understand the sensitivities of birds, and their capacity to adapt to environmental stress, especially in the face of rapid and pervasive global change. However, most of the research examining the effects of urbanization on wildlife has taken place in Europe and (North) America. However, this research field is one in which research findings might not be applicable outside of the study areas because of major differences across the globe in (i) how cities grow (e.g. in terms of building structures, the amount of green space or transport infrastructure), and (ii) their demographic patterns (e.g. in Africa mainly the youth is migrating into cities which might result in a different framework for conservation and citizen science projects and could influence the amount of bird feeders or nest boxes provided). This EOU symposium aims to identify shared ‘common ground’ by focusing on subjects within the emerging discipline of urban ecology which can be treated as global phenomena. Once achieved, we would like to identify important research gaps to attract people from places where urban ecology is still under-represented in the research arena and where the transfer of knowledge gained elsewhere might have far less traction compared with countries where the discipline is more mature. We aim to integrate approaches at the individual and population levels and bring urban ecologists from across the globe together. Contributing speakers come from a wide geographic range in their ‘study systems’ and this promises to result in the emergence of new perspectives on the impacts of urbanization on birds in a global context.

In the following round table discussions, we will highlight features that benefit and, in turn, threatens urban birds in general, and particularly that help retain a substantial amount of native birds in an urban environment. Bird are important bioindicators and provide many ecosystem services to cities, thus, having healthy ‘natural’ bird communities in cities is beneficial for our human wellbeing. Features like the urban heat island effect, water availability or predation risk by domestic cats might be important across the globe, while supplementary feeding or the installment of artificial nest boxes might be only relevant in some regions. The main aim of this part of the symposium will be to initiate a working group to compile these features from a global and regional perspective, that could result in a review paper containing a list of recommendations for city planners (according to continent or eco-region) to be used in the development of future cities.


Urban development is occurring at unprecedented rates across the globe, posing a major threat to biodiversity. Over half of the world’s human population live in urban areas and, by 2030, this is expected to rise to 66% (United Nations, 2014). Alongside climate change, the United Nations considers urbanization to be the biggest environmental challenge of our time, underlining the importance of the issue. Environmental changes associated with anthropogenic activities are likely to be an important factor governing the future persistence of species and ecological communities. In response, the urgent need to understand the impacts of urbanization on wildlife has gained increasing attention amongst professional scientists, citizen scientists and policy makers. While urban ecology research initially focused on describing the effects on biodiversity and community composition, attention has more recently turned to understanding the mechanisms driving observed changes in behavior, morphology and physiology in response to urban stressors. It is only by understanding the mechanisms underlying environmentally-induced variation that we will be able to begin to answer questions concerning the capacity of individuals and populations to cope with, or to adapt to, urbanization as a process. In this symposium we would like to provide a platform to highlight recent findings in avian urban ecology and share knowledge of novel techniques and approaches that could be applied more widely within the discipline. We hope the symposium and following round table discussions will foster new collaborations, particularly those involving researchers from different continents.