Effects of human disturbance on spatial and temporal feeding patterns of Blackbird Turdus merula in urban parks in Madrid, Spain

We studied how human presence in three urban parks in Madrid (Spain) might affect Blackbird densities by changing feeding behaviour patterns. Our specific purposes were: (a) to ascertain the effect of park visitors on Blackbird feeding behaviour; (b) to analyse the influence of human disturbance on foraging success; and (c) to determine how humans affect Blackbird spatial and temporal patterns of habitat use. Pedestrians were the main source of flushing responses in ail sampled parks, followed by Magpies Pica pica and dogs accompanying visitors. Blackbird responses to visitors entailed more time being vigilant and moving away from people and less time searching for food (decreasing food intake), a response that remained constant in the three parks. The number of pedestrians was positively correlated with Blackbird distance to pathways and negatively correlated with distance to protective cover. The number of active birds decreased with increase in the number of pedestrians during the day. Blackbird density was negatively related to the number of visitors per park. Our results confirmed that human disturbance negatively affects Blackbird feeding strategies in urban parks, ultimately modifying spatial and temporal patterns of habitat selection and abundance. Since such responses could also affect densities of other urban species by the same process, we propose some management measures to decrease the levels of disturbance as well as to enhance the recreational use of urban parks.