The raptor lockdown menu—Shifts in prey composition suggest urban peregrine diets are linked to human activities

Abstract

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.

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