Predation of Chlorostilbon lucidus (Shaw, 1812) (Apodiformes: Trochilidae) hummingbird chicks by Polistes canadensis (Linnaeus, 1758) (Polistinae: Polistini): A new predatory interaction documented in the Brazilian Caatinga

Non-aggressive interactions between Neotropical social wasps (Vespidae) and birds frequently occur but remain poorly understood. Typically categorized as commensalism, where birds benefit while no advantages for the wasps have been documented, the intricate dynamics of these associations have gone unexplored. These wasps, which are generalist feeders primarily relying on nectar, fruits, arthropods, and carrion, are seldom reported as vertebrate predators. In this study, we present a novel observation of the red social paper wasp, Polistes canadensis (Linnaeus, 1758) (Polistinae: Polistini), preying on young glittering-bellied emerald hummingbirds - Chlorostilbon lucidus (Shaw, 1812) (Apodiformes: Trochilidae), opportunistically recorded in the urban area of Brazilian Caatinga biome. Predation occurred when a Polistes canadensis individual targeted a hummingbird's nest. This occurrence challenges the prevailing view of these associations and suggests that social wasps may play a more significant role as nestling predators than previously acknowledged, highlighting the need for further research.