Behavioural differences and genetic relationships between four captive populations of red junglefowl (Gallus gallus) : possible implications for conservation

Abstract: Conservation of species is to a large extent carried out by zoos where animals are kept in small populations under protected conditions. The ultimate goal of such ex situ conservation programs is to eventually reintroduce the animals into natural habitats to provide support for the survival of the species. However, reintroduction has encountered considerable difficulty in the past, often due to behavioural deficiencies. Maintaining animals in captivity may lead to behavioural modifications as a result of adaptation to the captive environment, altered selection pressures and loss of genetic variation. The overall aim of this thesis was to study behavioural and genetic aspects of ex situ conservation and investigate whether maintenance of smal1 populations in captivity causes modifications which can affect the survival and reproduction capacity of the animals in a hypothetical reintroduction situation. Throughout the project the red junglefowl (Callus gallus) is used as a model for ex situ conservation populations. In Paper I, the behavioural variation between four captive populations of red junglefowl was studied. The birds were tested in different test situations; anti-predatory behaviour test, social behaviour test and exploratory and sociality test. The results showed clear behavioural differences between the populations, some of which are relevant from a conservation perspective. In Paper 11, the genetic relationships between the populations were examined by microsatellite analysis and possible correlations with the results of Paper I were investigated. The results showed that the populations were genetically differentiated and that all populations had lost a considerable amount of their assumed original genetic variation. Furthermore, the genetic variation of each population fo11owed the same pattern as behavioural variation ranks. The populations which had the highest genetic variation were also the ones showing the most behavioural variation in most behavioural variables. The results of Papers I and II imply that maintenance in captivity can affect an animal behaviourally as well as genetically. Even though the red junglefowl is merely used as a model here, the studies suggest that these issues are important to consider also in species where reintroduction is a more central motive for keeping the animals in captivity.