No evidence of a founder effect in Rainbow Lorikeet vocalisations following a population bottleneck

Abstract

The isolated population of Rainbow Lorikeets (Trichoglossus haematodus) in Perth, Western Australia, was founded by fewer than 10 birds introduced in the early 1960s. I recorded vocalisations of individuals in Perth, and from >2000 km away, at one site in South Australia and one in Victoria, to determine if the Perth population showed evidence of a founder effect in three common types of vocal signals. I measured spectral features of the calls of each recorded bird. Linear discriminant analysis indicated the three population samples differed significantly for all three call-types but there was no consistent trend suggesting the Perth birds retained evidence of a founder effect in these calls. Calls of Perth birds were not more simplified or more homogeneous in their acoustic traits. Although it is possible that there are founder effects for total vocal repertoires, which was not assessed here, there was no evidence for a founder effect in these most conspicuous vocalisations.