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Raptors can thrive in cities where food supplies are abundant and seasonally stable. The availability of such resources may be linked to spatiotemporally predictable human activities generating reliable food subsidies for both raptors and their prey, capable of sustaining large populations. However, raptors may become affected by shifts in human behaviour.Here, we explore how urban peregrine falcon Falco peregrinus diets respond to changes in human activity levels amidst COVID‐19 pandemic social restrictions. We used online nest cameras to study peregrine diets and reproduction across 31 sites in 27 UK cities over three breeding seasons, including one during lockdown.Prey composition changed significantly between years, and these differences varied by region. During lockdown, London peregrines took a lower proportion of pigeons (−14.5%), offset by a greater proportion of starlings Sturnus vulgaris (+6.9%) and ring‐necked parakeets Psittacula krameri (+3.2%). In other cities, lockdown diets showed no change for pigeons (+0.3%), starlings comprised a lower prey proportion (−4.3%), while non‐dominant corvid prey (+2.3%) and waterbirds (+2%) had greater importance. Racing pigeon prey also decreased during lockdown, significantly outside London.However, breeding parameters (number of eggs, hatchlings, fledglings) were not significantly different, suggesting urban peregrines may not have experienced food shortages amidst restrictions.Thus, our study demonstrates that human activity can influence urban peregrine predation opportunities but is unlikely to be more important than other factors like habitat availability. It also highlights how impacts can vary regionally, which may have been driven by social and geographical differences between the capital and other cities. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Raptors can be important components of urban ecosystems due to their role as apex predators, the presence of which may bring benefits to people. Urban environments may provide good quality habitats, and the raptors' ability to utilize resources found here can contribute to their success. However, urban environments are socio-ecological systems and such mechanisms shaping habitats and ecological resources therein are less understood. This paper explores how raptors utilize urban resources, and the socio-ecological processes influencing their quality and availability. It begins with a systematic mapping of the literature to summarize the utility of urban resources by raptors with European distributions. Eighteen species were documented in the literature successfully exploiting novel hunting and/or nesting opportunities in both green and built-up locations of urban areas. We discuss how these may be consequential of human activities, some of which intentionally provided as subsidies, and how their utility by raptors create opportunities for human-raptor interactions further shaping public perception and decisions which potentially affect the raptors. Finally, we demonstrate these concepts by drawing on our experience from an urban peregrine falcon (Falco peregrinus) conservation site in London, UK. The paper concludes with a call for urban raptor conservation and research to consider social and ecological aspects together, appropriately reflecting urban environments as socio-ecological systems. [ABSTRACT FROM AUTHOR]

Understanding habitat selection by individual animals within their home range is crucial to facilitating their conservation. Peregrine falcon (Falco peregrinus) populations are increasingly urbanised, but little is known about their urban habitat use. In this study, we analysed the breeding habitat selection of peregrine falcons in London, United Kingdom, based on nest site locations identified through records of public sightings submitted to an online database between 2003 and 2018. We found peregrines displayed a preference for nesting in proximity to waterbodies, built-up areas and public parks and gardens, while wooded, agricultural and allotments areas were least preferred. We hypothesise that peregrines seek contrasting topography that proves advantageous for hunting in the vicinity of their nests, resulting in their selection of breeding sites within tall buildings that are adjacent to suitable foraging areas. From these findings, we conclude that (i) social drivers such as demand for green spaces and waterbodies near buildings shape peregrine nesting opportunities in the city and (ii) for urban planning to support conservation, we need further understanding of how each type of greenspace may be used differentially by raptors. [ABSTRACT FROM AUTHOR]

The River Thames through central London has seen significant environmental recovery, particularly in regard to water quality, but a substantial barrier to further ecological improvement is the spatial restriction of riparian areas. Flood defence walls represent a potential habitat for ecological improvements to benefit biodiversity. However before restoration actions are considered, an understanding of the current biodiversity and ecological status of these structures is necessary. Physical habitat and macroinvertebrate richness of flood defence walls at 15, evenly spaced sites along a 32 Km reach in central London were evaluated. We found no longitudinal patterns in total macroinvertebrate richness among our 15 sites, but did find that richness was influenced by wall type. Specifically, we found the highest richness on brick walls and lowest richness on concrete walls. Further, wall sections with algal cover supported significantly higher numbers of macroinvertebrates than sections lacking algal cover. However, reaches of the river where the channel was constricted had fewer macroinvertebrates likely due to scouring flows. These results show that macroinvertebrates of the river walls are influenced by habitat availability (i.e., wall type) and localised river flows. This work suggests that appropriate management of river wall habitats has the potential to enhance the biodiversity of highly modified, urban rivers. [ABSTRACT FROM AUTHOR]

Urban rivers have often experienced substantial engineering modification and consequently are highly degraded aquatic ecosystems with minimal riparian habitat. Habitat restoration and improvement efforts are needed within urban rivers to support ecological communities and increase ecosystem integrity. Most river restoration techniques are not feasible within large urban rivers, and so there is a need to develop novel methodologies. Artificial structures such as river walls can function as habitat for plant and invertebrate species in urban rivers, and in some cases can be more diverse than remnant habitat. Along the River Thames through central London, plant species richness was found to be significantly higher on river walls than intertidal foreshore, which represents the only remnant habitat for riparian species. Both this survey and other studies have suggested that the physical and environmental characteristics of river walls are likely to influence their capacity to function as ecological habitat, for example, walls composed of more complex construction materials (brick and boulders) being more diverse than simpler structures (concrete and sheet piling). The opportunity exists to use river walls and other artificial structures (e.g., jetties) to improve habitat along urban rivers by installing walls which are designed to be more complex, or by adding modifications to existing walls. Some trial modifications, such as the addition of wall ledges and timber fenders to sheet piling, have been installed at Deptford Creek along the River Thames, and have so far greatly supported the colonization and development of plant communities. The restoration possibilities of such modifications should be considered, and further development and rigorous testing of installations is required in urban rivers to make sound restoration recommendations. [ABSTRACT FROM AUTHOR]