Abstract
Intentional feeding of wild birds in gardens or backyards is one of the most popular forms of human-wildlife interactions in the developed world, especially in urban environments. Scale and intensity of bird feeding are enormous with mainly birdseed consumed daily by a range of species. This represents a subsidy to natural diets of birds attracted to the feeders and typically involves novel dietary components. Yet, relatively little is known about how it influences the behavior and ecology of the species visiting feeders. In part, research has been hampered by logistical difficulties of working in urban areas but studies have demonstrated powerful influences on behavior and phenology of avian breeding, the spread of disease, and the structure of avian communities. Here, we compare bird feeding between Northern and Southern Hemispheres as a means of exploring how similarities and differences in avian responses might inform knowledge of this global urban phenomenon. We start by tracing its origins to north-western Europe and how its expansion has occurred before considering how geographical differences in feeding practices and attitudes map onto bird feeding ‘on the ground’. We explore some of the major emerging themes of recent interest, including why citizens are motivated to feed birds, whether birds become fully dependent on food supplements, the role of feeding in avian disease transmission, and how feeding changes urban bird communities. By proposing that scientists work in collaboration with the public providing food to birds, we pose key research questions that need to be answered urgently and suggest accompanying experimental approaches to do so. These approaches are essential if we are to improve our understanding of how bird feeding shapes the behavior, ecology, movements, and community structure of urban birds. Our hope is that through such citizen science we will be able to provide advice as to location-relevant practices that should maximise benefits to both urban biodiversity and human wellbeing, and minimise potential adverse impacts. We demonstrate that bird feeding is important for urban biodiversity conservation, community engagement, and in establishing personal connections with nature and their associated benefits.
Highlights
The world is urbanizing rapidly (United Nations, Department of Economic and Social Affairs, Population Division, 2014) and, as a result, human–wildlife interactions will become ever more commonplace
In the United Kingdom (UK) and the rest of temperate Europe the introduced rose-ringed parakeet Psittacula krameri has established in many cities with its success at least in part associated with access to urban bird feeders (Clergeau and Vergnes, 2011)
The research questions posed here are framed by the comparison of the impacts of feeding on urban birds between the Northern and Southern Hemispheres
Summary
While species richness at feeders is high in all countries where garden bird feeding is a common pastime, by far the most frequent visitors in North America are black-capped chickadees Poecile atricapillus and Carolina chickadees Poecile carolinensis, and blue and great tits Parus major in the UK, all being members of the family Paridae (Toms and Sterry, 2008; Baicich et al, 2015). The most commonly provisioned form of meat is raw beef mince (or ground beef), presumably because it is relatively inexpensive and readily available, pieces of sausage, salami, ham, bacon, and cooked chicken are provided (Ishigame and Baxter, 2007) This raises many concerns including the impacts on bird communities dominated by large and often predatory species, the hygiene of feeding structures, and the nutritional impacts if these food supplements were to constitute a large proportion of their diets. For example, that are specialized consumers of pollen and nectar have learned to consume meat supplements too; this recent expansion of their foraging niche is resulting in much consternation among participants and ecologists (Gillanders et al, in press)
Published Version (Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have