Extended cubs’ care helping as a factor of reproductive success in a resident Golden jackal (Canis aureus Linnaeus, 1758) family group

A resident Golden jackal family behaviour was studied over eight years (2017-2024) and especially over two successive post-birth seasons (May-September) in 2023 and 2024, utilising stationary bait-site camera-trap recordings on the Bulgarian bank of the Danube River. Earlier research on the cooperative breeding in golden jackals suggests that the cubs are typically cared for by the breeding pair and possibly by young helpers (1+/ 2+ years old). However, here we show that the presence of an adult, non-breeding helper (‘uncle’) can be systematic, helping the breeding female for several years, thus replacing the father, who, in our case, did not seem to contribute in the care for the young. Our observations also suggest repeated instances of food sharing by the non-breeding senior male adult, directed towards junior adults (last year’s jackals). Furthermore, food sharing behaviour amongst junior adults and towards the cubs was also recorded. Our data help revealing a more extended presence of ’helpers’ than is traditionally described in literature, with more than one or two junior adults remaining with the group to assist the breeding female during the denning period. This extended helping behaviour may contribute to the resilience of jackal family groups, particularly in contexts of pronounced hunting pressure, as is the case within our study area. We conclude that this specific behaviour, amongst other factors, may help to explain the demographic success in the European Golden jackal and with this, its significant recent expansion beyond its traditional habitats.