Duncan Y. W. Leong

In developed cities, bird communities are typically comprised of a few dominant invasive species that can cause considerable social and economic costs. While various studies advocate restricting anthropogenic food as a suitable management approach, a significant knowledge gap persists regarding how these species interact and respond to such an intervention. Here, we evaluate whether limiting a shared food resource may affect their abundances similarly and assess whether such limitations influence their niche dynamics. In Singapore, open food centres for people, colloquially known as hawker centres, serve as key food sources for three highly adapted urban birds: feral pigeons, Javan mynas and house crows. We counted these three species across 63 hawker centres and analysed their niche dynamics across different phases—before, during COVID‐19 social restrictions when dining‐in was prohibited, and during an enforcement phase mandating the return of crockery. We modelled their counts, diet niche widths and niche overlaps, considering predictors which include the sampling phases, food availability, structural characteristics of hawker centres and spatial attributes such as distance to public housing. During social restrictions, feral pigeon and Javan myna counts showed a significant decline, while the count proportions of the three species compared to each other remained relatively stable. Hawker centres closer to bridges and public housing, and those that structurally more open, attracted more birds. The niche widths of feral pigeons and Javan mynas significantly narrowed during social restrictions due to reduced food availability. However, their niche overlaps remained consistent across sampling phases, indicating resource partitioning strategies to cope with extreme food shortages—feral pigeons adapted by foraging more on grass verges outside, while Javan mynas frequented tray return stations. This resilience in maintaining species proportions and the absence of significant niche overlap suggested the existence of an ecological balance despite substantial reductions in available food. Synthesis and applications. Our study underscores the importance of controlling human‐provided food to collectively manage dominant urban bird commensals. Beyond the two social restriction phases, curbing the availability of anthropogenic food through enforcement also kept nuisance birds away, validating a cost‐effective approach in reducing their counts.

The feral pigeon (Columba livia) is a globally commensal bird that can cause dis‐amenities such as soiling and is a potential vector of various diseases. Aside to limiting food as a management strategy, reducing the availability of roosting and nesting sites can help regulate feral pigeon populations. Despite their prevalence, current knowledge of their roosting and nesting preferences is lacking. Feral pigeons commonly use railway viaduct expansion gaps in Singapore for roosting and nesting. These gaps provided an ideal experimental platform to examine feral pigeon roost and nest site selection while controlling for differing cavity sizes which can significantly affect their reproductive success and site selection decisions. We also conducted an in‐situ experiment to test the efficacy of nest removal as a management option. Our nationwide surveys of 80.3 km of railway viaducts and 6048 gaps revealed that feral pigeon day roosting and nesting preferences are influenced by structural height and more importantly, their proximity to human food sources. There was a significantly higher probability of feral pigeon roosting in a gap if it had more pigeon feeding incidences in its vicinity and was higher. The probability of feral pigeon nesting in gap was higher if it was closer to a railway station, lower and further from water bodies. In our field experiment, we did not find any significant differences in the proportions of the abundances of feral pigeon to other urban commensal bird species at the gaps before and after nests were removed. Overall, our results suggest that a concerted effort to reduce anthropogenic food availability to feral pigeons is central in limiting their reproductive success and controlling their population.