Even more generalist: an invasive crayfish as a novel food source for Common Buzzards

Generalist predators exploit a wide range of food resources, making them more adaptable. Sometimes, the appearance of a new species can lead to their exploitation, especially when it is abundant. In this sense, Red Swamp Crayfishes Procambarus clarkii, one of the most dangerous freshwater exotic species in the world, are an important food resource for some species in their non-native range.We describe a newly observed behaviour and food source for Common Buzzards Buteo bu-teo in Western Iberia, where Red Swamp Crayfish appear to be a recurrent resource in late summer. The buzzards exhibited riverbank-patrolling behaviour and consumed this crusta-cean alongside other prey species. This behaviour represents the discovery of a new inver-tebrate taxon (Crustacea) in the diet of the Common Buzzard, thereby broadening its known trophic spectrum. Future research should explore whether Common Buzzards exploit sim-ilar resources in other regions, particularly where they may prey on other invasive species.