Biology of the greyheaded parrot Poicephalus fuscicollis suahelicus Reichnow.
This study was conducted to investigate the biology of the Greyheaded Parrot Poicephalus fuscicollis suahelicus in the wild. Field work was conducted in north-east South Africa in the southern limit of the range of the Greyheaded Parrot during two field seasons. Observations from August to December 1999 in the Levubu region, south of the Soutpansberg mountain range, included months of the non-breeding season when Greyheaded Parrots occur seasonally in the area. Observations in the Luvhuvhu-Mutale river confluence area from March to August 2000 included months of the breeding season. No field work was conducted from January to March 2000 due to exceptionally high rains in the southern African sub-region, that prevented access to sites. The Greyheaded Parrot has a widespread distribution, through southern, south Central and East Africa, that has possible changed little in recent years. However, local populations are likely to have suffered extinctions due to habitat destruction and capture for the illegal trade. Populations in protected areas (Makuya Park and Kruger National Park) are less vulnerable to capture than unprotected areas. The conservation of the Greyheaded Parrot outside of protected areas is highlighted. In various parts of the range of the Greyheaded Parrot seasonal movements occur in response to food and nest site availability. Nest sites are possibly limiting in certain parts of its range due to habitat destruction. During post-breeding flocking, the occurrence of larger flocks, possibly family units (mean ± S.E = 4.7 ± 0.2), is common, when birds wander in search for seasonally available food sources. During this period density of Greyheaded Parrots is 0.28 birds/100 ha. Monogamous pairs are more conspicuous during the breeding season (mean ± S.E = 2.1 ± 0.1) and density estimates are 0.14 birds/100 ha. Egg laying is synchronous between pairs with the timed appearance and flocking of juvenile flocks in spring (August/September). Breeding during the dry season reduces competition with other large cavity nesting bird species. Observations suggest that a skewed sex ratio exists in the population (males:females = 2:1). Daily movements are characterised by a bimodal activity pattern. Early morning movements involve flights to activity centres where the accumulation of numerous smaller flocks occur. Here preening, allo-preening and socializing occur with drinking and/or feeding occurring if food and/or water are available. Thereafter, birds move to regular feeding sites, to feed. Activity is decreased during the heat of the day with birds sleeping, resting and/or preening in the canopies of trees. Late afternoon activities involve increased levels of activity and late afternoon return flights to roosts. Greyheaded Parrots are specialist feeders, accessing the kernel of predominantly unripe fruit. This feeding strategy reduces competition with other frugivore competitors. During any one time few tree species are fed on by the Greyheaded Parrot. Greyheaded Parrots were also observed feeding on bark in the breeding season. Two, almost fully fledged, chicks were found dead in a nest and the causes of death undetermined. Their crops contained numerous pieces of masticated bark and insect parts. Behaviours and vocalizations of the Greyheaded Parrot were similar to that recorded in the Cape Parrot. Recognition of the Greyheaded Parrot as a separate species based on species specific calls and DNA warrants further investigation.