Cooperative breeding behaviour of the endangered El Oro Parakeet (Pyrrhura orcesi)

Aim of my Diploma thesis is to get further insights into the complex social system within the flocks of Pyrrhura orcesi in the Buenaventura Reserve (owned by the Fundación Jocotoco) in Southwestern Ecuador. The total El Oro Parakeet population consists of less than 1000 individuals and is therefore classified as an endangered species by IUCN. During the breeding season from November to April this facultative cooperative breeder lives in groups of 2-8 individuals. In addition to the breeding pair, last year’s offspring and unrelated individuals help raising the chicks.

My behavioural observations consist mainly of analysing video material recorded by nest cameras installed onto the artificial nest boxes when occupied by Pyrrhura orcesi (see picture). All individuals of a group are captured with trapdoors in the nest box and are then individually marked with colour and feather marks. Photos are taken of each individual to further facilitate identification of each bird in the videos. The nest activity in the hatching phase is recorded for several days during daytime in each occupied nest and allows me to analyse the social structure and individual behaviour of birds within the groups.

Individual social behavior comprehends provisioning the offspring, allopreening, aggressive interactions and guarding the nest entry. These different behaviours are then compared amongst members of the groups to determine whether the degree of relatedness between individuals affects helping behaviour and if there exist sex differences in helping behaviour. The comparison with other flock members, birds from other groups and the individual behaviour in previous seasons aims to reveal the causes, benefits and a potential 'personality' of different birds. Comparing breeding success and survival of offspring between different sized flocks provides further information about the direct and indirect benefits of different strategies.

My behavioural study is closely connected to the dissertation of Nadine Klauke and will be complemented with these genetic analyses.

My field work in Ecuador was supported by DAAD.