Food, family and female age affect reproduction and pup survival of African wild dogs

Understanding factors that affect the reproductive output and growth of a population of endangered carnivores is key to providing information for their effective conservation. Here, we assessed patterns in reproduction for a small population of endangered African wild dogs (Lycaon pictus) over 90 pack years. We tested how availability of prey, pack size, pack density, rainfall, temperature and female age affected the age of first litter, litter size and pup survival. We found that females bred younger when pack density, availability of prey and pack size were large.We also found that fecundity increased significantly with age while the population was male biased only for 1-, 2- and 4-year olds. Larger litters were produced by larger packs, suggesting strong reproductive benefits of grouping related to cooperative hunting and food provisioning for helpers and alpha females. We also found an interaction between breeding female age and pack size where older females in large packs raised a high proportion of pups. Additionally, large litters and large packs were important for raising a greater number of pups to 6 and 12 months, respectively, suggesting that while litter size is important for pup survival, the benefits of a large pack are only realised when pups are older and mobile with the pack. Collectively, these results illustrate the novel finding that prey availability is critically important in initiating reproduction inwild dogs and that the number of non-breeding helpers, female age and litter size is essential to pup survival

Thyroid hormones in serious non-thyroidal illness

SCOPUS: le.jinfo:eu-repo/semantics/publishe

Factors affecting the success of artificial pack formation in an endangered, social carnivore: the African wild dog

Social integration is an important factor when reintroducing group-living species, but examples of the formation of social groups before reintroduction are largely lacking. African wild dogs Lycaon pictus are endangered, and reintroductions have become a routine part of range expansion in South Africa. Wild dogs form packs that are essential to their reproduction and survival, and artificial pack formation is often required before reintroduction. We examined the proximate (i.e. social integration) and ultimate (i.e. reproduction) success of 43 artificial pack formation attempts in the South African managed metapopulation, between 1995 and 2018. The top (and dominant) model for proximate success included an interaction between total group size and an initial separation fence. Larger groups took longer to integrate, irrespective of initial separation, whereas smaller groups brought together immediately integrated faster than those that were initially separated. The top models for ultimate success included an interaction between the proportion of males and number of days spent in the pre-release enclosure, the total number of days in the enclosure and an interaction between the proportion of captive-sourced individuals and the total number of days in the enclosure. Ultimate success increased when packs spent less time in the enclosure, especially if those packs had a low proportion of males (i.e. female biased) or included >25% captive-sourced individuals. Neither the size of the artificially created pack nor the season in which the pack was released affected ultimate success. The success of social integration and reproductive success of artificially formed packs in this study was higher than for natural pack formations. We provide guidelines for optimizing future artificial pack formation in wild dogs for reintroduction success. Our results serve as an example of the practical importance of social behavior in successfully implementing conservation measures for group-living species

Factors affecting the success of artificial pack formation in an endangered, social carnivore: the African wild dog

Social integration is an important factor when reintroducing group-living species, but examples of the formation of social groups before reintroduction are largely lacking. African wild dogs Lycaon pictus are endangered, and reintroductions have become a routine part of range expansion in South Africa. Wild dogs form packs that are essential to their reproduction and survival, and artificial pack formation is often required before reintroduction. We examined the proximate (i.e. social integration) and ultimate (i.e. reproduction) success of 43 artificial pack formation attempts in the South African managed metapopulation, between 1995 and 2018. The top (and dominant) model for proximate success included an interaction between total group size and an initial separation fence. Larger groups took longer to integrate, irrespective of initial separation, whereas smaller groups brought together immediately integrated faster than those that were initially separated. The top models for ultimate success included an interaction between the proportion of males and number of days spent in the pre-release enclosure, the total number of days in the enclosure and an interaction between the proportion of captive-sourced individuals and the total number of days in the enclosure. Ultimate success increased when packs spent less time in the enclosure, especially if those packs had a low proportion of males (i.e. female biased) or included >25% captive-sourced individuals. Neither the size of the artificially created pack nor the season in which the pack was released affected ultimate success. The success of social integration and reproductive success of artificially formed packs in this study was higher than for natural pack formations. We provide guidelines for optimizing future artificial pack formation in wild dogs for reintroduction success. Our results serve as an example of the practical importance of social behavior in successfully implementing conservation measures for group-living species

Factors affecting the success of artificial pack formation in an endangered, social carnivore: the African wild dog

Social integration is an important factor when reintroducing group-living species, but examples of the formation of social groups before reintroduction are largely lacking. African wild dogs Lycaon pictus are endangered, and reintroductions have become a routine part of range expansion in South Africa. Wild dogs form packs that are essential to their reproduction and survival, and artificial pack formation is often required before reintroduction. We examined the proximate (i.e. social integration) and ultimate (i.e. reproduction) success of 43 artificial pack formation attempts in the South African managed metapopulation, between 1995 and 2018. The top (and dominant) model for proximate success included an interaction between total group size and an initial separation fence. Larger groups took longer to integrate, irrespective of initial separation, whereas smaller groups brought together immediately integrated faster than those that were initially separated. The top models for ultimate success included an interaction between the proportion of males and number of days spent in the pre-release enclosure, the total number of days in the enclosure and an interaction between the proportion of captive-sourced individuals and the total number of days in the enclosure. Ultimate success increased when packs spent less time in the enclosure, especially if those packs had a low proportion of males (i.e. female biased) or included >25% captive-sourced individuals. Neither the size of the artificially created pack nor the season in which the pack was released affected ultimate success. The success of social integration and reproductive success of artificially formed packs in this study was higher than for natural pack formations. We provide guidelines for optimizing future artificial pack formation in wild dogs for reintroduction success. Our results serve as an example of the practical importance of social behavior in successfully implementing conservation measures for group-living species