Skip to content

Hooded Crows Used Urban Habitats Differently In and Outside the Breeding Season

Hooded crow (Corvus cornix) standing on a street in Budapest, Hungary
Research · Ecology

Hooded crows (Corvus corone cornix) used different parts of the city depending on season in a three-year study from Debrecen in eastern Hungary. The study, published on 19 February 2026, found that nesting birds were associated mainly with nest-site availability, while non-breeding flocks increasingly concentrated where anthropogenic food was abundant.

A transect is a predefined line or route used to survey an area systematically, with observations, signs or sampling points recorded along it.

Researchers surveyed 16 urban sections along a roughly 10-km transect in northern Debrecen between December 2016 and December 2019. The sections included parks, residential areas and sports complexes and differed in their area, number of nests, restaurants and public trashbins. In total, 241 surveys were completed across breeding and non-breeding periods.

Nesting crows favoured quieter urban settings

During the breeding season, when pairs defend territories, the number of crows increased with the availability of nesting sites and with the number of trashbins. Habitat type itself did not explain the number of birds recorded. However, the probability that crows colonised a section between breeding seasons showed a different pattern: it was high in parks, sports complexes and quieter residential areas, and low in residential areas with heavy traffic.

Breeding-season hooded crow numbers in Debrecen in relation to nest availability and trashbins
During the breeding season, crow numbers increased with nest availability at the smaller spatial scale and with trashbins at the larger scale. Figure 2 from Paládi et al. (2026), Scientific Reports, CC BY 4.0.

Colonisation probability also declined as the number of trashbins and restaurants increased. The authors interpret this contrast as evidence that anthropogenic food can attract crows for feeding without necessarily making the same places favourable for establishing nesting territories, particularly where human disturbance is high.

Hooded crow occupancy and colonisation probabilities in Debrecen in relation to urban habitat variables
Estimated occupancy, colonisation and detection probabilities across the 16 urban sections and their relationships with habitat variables. Figure 4 from Paládi et al. (2026), Scientific Reports, CC BY 4.0.

Non-breeding flocks concentrated around food

Outside the breeding season, the spatial pattern changed. Hooded crows form larger mobile groups after breeding, and in the surveyed sections their numbers increased over time in the area with the highest number of trashbins. Numbers declined in residential areas and remained comparatively stable in parks and sports complexes.

The study therefore separates two important parts of urban habitat use. Nesting requires suitable sites in areas where disturbance is tolerable, while non-breeding flocks can move widely and exploit concentrated food resources. Debrecen is a useful setting for examining this process because hooded crows colonised the city relatively recently; the local breeding population grew from around 10 pairs in 2006 to more than 75 by 2012 and to about 150 pairs by 2019.

The results show that urban crow abundance cannot be explained by food availability alone. The importance of nesting sites, disturbance and food changes with the season and with whether birds are territorial or moving in flocks. The authors suggest that reducing access to anthropogenic food, for example through closed-top trashbins or covered waste areas, could reduce the attraction of some urban sites to crows, while management of breeding birds needs to account for the places where territories and nests are actually established.

Sources and image credit

  1. Paládi, P., Benmazouz, I., Tóth, M., Kövér, L., & Lengyel, S. (2026). Spatial and temporal dynamics in the use of urban habitats by Hooded Crows. Scientific Reports, 16, 9881. https://doi.org/10.1038/s41598-026-40561-zPrimary peer-reviewed open-access article published 19 February 2026 under CC BY 4.0. The study covered 16 urban sections in Debrecen, Hungary, with 241 surveys from December 2016 to December 2019 and found seasonal differences in habitat use and colonisation.

Image: Jakub Hałun / Wikimedia Commons — hooded crow (Corvus cornix) on a street in Budapest, Hungary, photographed 4 May 2019. Wikimedia Commons Quality Image; representative urban image from Hungary, not a bird from the Debrecen study. · CC BY-SA 4.0 — https://creativecommons.org/licenses/by-sa/4.0/ · Source

About this content: This story was produced with AI assistance within an editorial workflow developed by Wildlife Vagabond. Editorial responsibility remains with Wildlife Vagabond.How AI is used

Ecology

SPECIES IN THIS STORY

Species in this story

Hooded Crow Corvus corone cornix Explore species

Independent research and conservation news archive

Did you find this information useful?

Wildlife Vagabond is independently built and maintained. Voluntary support helps cover source verification, hosting and continued work on research and conservation news.

Support Wildlife Vagabond

The news archive will remain freely available.