V.P., J.B. and A.Z.-A. were financially supported by the I + D + i Project PID2020-114181GB-I00 funded by MCIN/AEI/10.13039/501100011033 and by the European Union. A.Z-A. was also financially supported by a Margarita Salas contract financed by the European Union (NextGenerationEU, Ministerio de Universidades y Plan de Recuperacion, Transformacion y Resiliencia) through the call of the Universidad de Oviedo (Asturias). The Finnish Ministry of Agriculture and Forestry financially supported Ilpo Kojola. Slavomír Find'o was financially supported by the project ITMS 26220120069 under the Operational Programme Research and Development funded by the European Regional Development Fund. Dr. Joachim and Hanna Schmidt Stiftung für Umwelt und Verkehr, Germany, financially supported Michaela Skuban. The financial support for A.F., M.F. and P.G.S. was provided by the project LIFE17NAT/IT/464 SAFE-CROSSING, by a grant (Nucleu Programme PN 23090304) of the Romanian National Authority for Scientific Research and Innovation and ‘Creșterea capacității și performanței instituționale a INCDS Marin Drăcea în activitatea de CDI—CresPerfInst’ (Contract nr. 34PFE/30 December 2021) from the Ministry of Research, Innovation and Digitalization, Programul 1—Dezvoltarea sistemului naţional de cercetare—dezvoltare, Subprogram 1.2—Performanţă instituţională—Proiecte de finanţare a excelenţei în CDI.

Infanticide is a significant evolutionary force influencing carnivore behaviours, as it is one of the primary contributors to offspring mortality. Female multimale mating, which creates paternal uncertainty, is known to reduce infanticide. We propose that two crucial steps are needed for this strategy to work in solitary species like brown bears, Ursus arctos. First, after mating, females should choose dens within their mating area (step 1), boosting the chances of encountering potential fathers of cub(s) after den emergence in spring. However, the efficacy of this strategy hinges on males' fidelity to the same mating areas from one year to the next (step 2). Our study confirmed that pregnant females consistently selected dens within their mating areas, with significant overlap (around 90%) between areas used by females with cubs and their mating zones. Males also demonstrated fidelity (over 65%) to mating areas over 2 consecutive years. Infanticide significantly shapes the sociospatial ecology of female brown bears, a phenomenon that can carry nutritional costs for females with cubs, and influence settlement patterns near human shields to increase reproductive success. Additionally, in hunted populations, removing resident males can trigger an influx of potentially infanticidal bears from elsewhere.

© 2024 The Authors. Published by Elsevier Ltd on behalf of The Association for the Study of Animal Behaviour. This is an open access article under the CC BY-NCND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Peer reviewed