Search

Little is known about moult and moult-site fidelity of African waterfowl. Satellite telemetry and uniquely engraved colour-rings were used to study moult-site fidelity of Egyptian geese marked at two sites in South Africa – Barberspan in the summer-rainfall region and Strandfontein in the winter-rainfall region. Twelve Egyptian geese were tagged with satellite GPS PTT transmitters while moulting at Barberspan and Strandfontein during 2008 and 2009, and a further 527 were colour-ringed between June 2007 and March 2009. Bi-monthly point counts of Egyptian geese and scans for colour-ringed birds were made at each study site from July 2007 until June 2010, resulting in 139 individually colour-ringed geese being re-sighted during the study period. We explored Egyptian geese dispersal distances away from the study sites and modelled moult-site fidelity from colour-ring return rates corrected for survivorship, sampling period efficiency and colour-ring detectability estimates. There were 12% and 29.7% colour-ring return rates for geese ringed at Barberspan and Strandfontein, respectively. Four of five moulting birds tagged at Barberspan with satellite transmitters returned to Barberspan to moult the following year. Two of these same birds moulted at Barberspan in the third year while the other two moulted elsewhere. One out of seven Egyptian geese satellitetagged at Strandfontein returned to the same site to moult the following year. One bird moulted at a nearby pan (5 km away), two moulted at estuaries less than 30 km from Strandfontein and one bird moulted at a farm dam 56 km away. Two birds satellite-tagged at Strandfontein did not moult the following year and returned to moult at Strandfontein in the third year. The moult-site fidelity model suggested that a minimum of 16% of Barberspan birds and 51% of Strandfontein birds returned to the same wetland to moult the following year. The apparent low moult-site fidelity at Barberspan suggested by colour-ring resightings may reflect the small number of birds colour-ringed at the site.Key words: waterfowl, Egyptian goose, southern Africa, telemetry, colour-ring.

Book Review 1Book Title: Mammoths, Mastodonts & Elephants; Biology, Behaviour, and the Fossil RecordBook Author: Gary HaynesCambridge University Press 1991. 413 pp.Book Review 2Book Title: A Fieldguide to the Amphibians and Reptiles of Madagascar (Second Edition)Book Authors: Frank Glaw & Miguel VeneesM, Venees & F. Glaw Verlags GbR, Köln, December 1994. 48O pagesBook Review 3Book Title: The Physiology of Reproduction; Second edition 1993Book Authors: Editors in Chief: E, Knobil & J.D. Neill Associate Editors: G.S. Greenwald, C.L. Markert & D.W. PfaffA two volume set, 3302 pages. Raven Press, New YorkBook Review 4Book Title: The Economics of Non-Human SocietiesBook Author: Gordon TullockPallas Press, March 1994 Tuscon, Arizona. 87 pages.Book Review 5Book Title: Bird Atlas of BotswanaBook Author: Huw PenryUniversity of Natal Press, Pietermaritzburg. 319 pages.Book Review 6Book Title: Colobine Monkeys: their Ecology, Behaviour and EvolutionBook Authors: A. Glyn Davies & John F. OatesCambridge University Press, Cambridge UK (1994). Pages xiii + 415.Book Review 7Book Title: Water Relations of Terrestrial ArthropodsBook Author: N.F. HadleyAcademic Press. 1994. 356 pages

The African Black Oystercatcher Haematopus moquini is classified as Near Threatened because the population size is small (

Theoretical and empirical studies of oystercatchers both suggest that levels of adult site fidelity, natal philopatry and age-at-first-breeding are interrelated consequences of life-history decisions made by potential breeders. All are fundamental to explaining population dynamics and have important conservation implications. The African Black Oystercatcher Haematopus moquini is classified as Near Threatened and virtually nothing is known of the biology of sexually mature birds that have yet to become established as breeders (i.e. ‘floaters’). Using an extensive ringing/ recapture/resighting data set from islands off the west coast of South Africa where densities of territorial oystercatchers are very high, this study aimed to explore (1) the degree to which African Black Oystercatchers exhibitnatal philopatry, (2) the age at which they enter the breeding population, and (3) the factors that might determine age-at-first-breeding. Both natal site philopatry and adult breeding site fidelity for island-reared birds were high with almost 100% returning to their natal sites. There is a clear, age-based recruitment pattern of oystercatchers into the island breeding populations, but time spent at a site, rather than age per se, may determine a bird’s success in establishing a territory.Keywords: age-at-first-breeding, Haematopidae, natal philopatry, nesting, recruitment, site fidelity

Southern Ground-Hornbills Bucorvus leadbeateri are Endangered in South Africa and there is a concerted effort to reverse their population decline. They live in groups year round, with only the alpha pair breeding, raising at most one chick per year. Each group has a home range of 50–100 km2, but there are few data for their spatial habitat use within this range. Understanding the factors affecting Southern Ground-Hornbill movement patterns is useful to assess habitat management options for the species, to select sites for artificial nests and to identify suitable areas for reintroduction initiatives. We report daily and seasonal patterns of habitat use by four groups in the Associated Private Nature Reserves, north-east South Africa, based on data from GPS-satellite tags. Daily travel distances averaged 7.4 ± 2.2 km d−1 but were greater during the breeding season, although birds were constrained to forage close to their nest, and were lower in winter, when birds ranged more widely. Hourly travel distances were affected by time of day, season, temperature and group. Birds travelled farthest per hour in the morning, decreasing in the afternoon in winter. However, in summer hourly travel distances were bimodally distributed, with a minimum during the middle of the day when ambient temperatures exceed 25 °C. Acacia-dominated vegetation and riparian habitats were favoured disproportionately during the heat of the day in summer, presumably because they offer more shade than other habitats. Optimal habitat configurations for ground-hornbills include a mosaic of habitat types, including open areas for foraging and dense trees for shade.Keywords: Bucorvus leadbeateri, habitat use, movement patterns, Southern Ground-Hornbill