A new parrot: Poicephalus robustus

The Cape parrot is a moderately large bird that lives in the temperate forests of South Africa. The Cape Parrot is critically endangered with an estimated current population size of less than 1600 birds in the wild. The rapid decline in numbers can be attributed to various factors, including habitat loss, illegal harvesting of wild birds and psittacine beak and feather disease.

The Cape Parrot is currently considered a sub-species called Poicephalus robustus robustus, along with two other subspecies, but based on morphological, ecological, and behavioral assessments, some scientists thought the Cape Parrot should actually be a distinct species. In a new study, researchers investigated this further by using DNA analyses and they could show that the Cape Parrot is genetically distinct from the other subspecies and therefore should be elevated to species level.

For the experts: The taxonomic position of the Cape Parrot (Poicephalus robustus robustus) has been the focus of much debate. A number of authors suggest that the Cape Parrot should be viewed as a distinct species separate from the other two P. robustus subspecies (P. r. fuscicollis and P. r. suahelicus). These recommendations were based on morphological, ecological, and behavioural assessments. In this study we investigated the validity of these recommendations using multilocus DNA analyses. We genotyped 138 specimens from five Poicephalus species (P. cryptoxanthus, P. gulielmi, P. meyeri, P. robustus, and P. rueppellii) using 11 microsatellite loci. Additionally, two mitochondrial (cytochrome oxidase I gene and 16S ribosomal RNA) and one nuclear intron (intron 7 of the β-fibrinogen gene) markers were amplified and sequenced. Bayesian clustering analysis and pairwise FST analysis of microsatellite data identified P. r. robustus as genetically distinct from the other P. robustus subspecies. Phylogenetic and molecular clock analyses on sequence data also supported the microsatellite analyses, placing P. r. robustus in a distinct clade separate from the other P. robustus subspecies. Molecular clock analysis places the most recent common ancestor between P. r. robustus and P. r. fuscicollis / P. r. suahelicus at 2.13 to 2.67 million years ago. Our results all support previous recommendations to elevate the Cape Parrot to species level. This will facilitate better planning and implementation of international and local conservation management strategies for the Cape Parrot.