From multifamily residences to studio apartments: shifts in burrow structures of E uropean rabbits along a rural‐to‐urban gradient

E uropean rabbits ( O ryctolagus cuniculus ) are currently declining in most rural areas throughout central E urope, while city populations often reach high densities. We asked whether and how altered environmental conditions affect the social organization and burrow structures of E uropean rabbit populations located at urban, suburban and rural sites in and around F rankfurt a. M . in G ermany. Burrow densities (numbers per ha) increased along the rural‐to‐urban gradient, accompanied by a gradual shift from accumulated towards more evenly distributed burrows. Burrows became smaller and less complex with increasing degree of urbanity, and accordingly, also the number of rabbits inhabiting the same burrow decreased. It remains unclear whether urbanization first led to smaller rabbit group sizes and burrow structures then shifted as a consequence of this, or vice versa. Nevertheless, for both scenarios, we propose that increased structural heterogeneity of urban landscapes is the major factor behind the observed effects, as mosaic‐like habitat patches in cities provide high and steady resource availability compared with the agriculturally transformed, open landscapes characterizing most rural areas in central Europe.