Exploring the complexities of cooperative breeding: insights from African wild dog packs

Abstract

Cooperative breeding, a rare trait in <1% of mammals, is explored within African wild dog packs (Lycaon pictus), where alpha females typically produce the first litters, but subordinate females may also breed, resulting in second litters within the same pack. We investigated the reproductive dynamics of wild dog packs in Zimbabwe's Savé Valley Conservancy (SVC) using 14 years of data from 49 packs and 131 den sites, obtained through spoor tracking, radio telemetry, sighting reports and camera traps during denning periods. Among packs capable of multiple litters, 41.15% of breeding events produced multiple litters annually, with 24.86% of all litters from subordinate females, primarily litter sisters of the alpha. Generalized linear mixed models revealed that younger packs and those with more subordinate females were significantly more likely to produce multiple litters, indicating weaker dominance hierarchies. Within multiple litter packs, pup survival to 1 year was significantly higher for second-born than first-born litters. However, 2-year survival significantly increased with higher pre-emergence rainfall, older alpha females and higher maximum temperatures. Across both litter types, 1-year and 2-year pup survival significantly improved with larger packs, while 2-year survival also significantly increased with pre-emergence rainfall. Pups from single litters had significantly lower survival to 2 years compared to multiple litters. Despite the potential for reproductive conflict, we found low infanticide (2%) and moderate pup stealing or adoption (14%), suggesting that kin selection promotes reproductive tolerance. These findings highlight the social and ecological complexity of cooperative breeding and its conservation relevance.