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A collection of almost 830 specimens of birds and their eggs was made at Deelfontein, Northern Cape province, South Africa, in 1901 and 1902, by two soldiers who had enlisted in the Yeomanry during the South African (Boer) War. A total of 151 bird species has been recorded in the Deelfontein area in two periods, 1901–1902 and 1987–1992. There has been no apparent change in occurrence in 82 species, but 40 species were recorded only in 1901–1902, and 29 species were recorded only by observers who completed field cards for the area for the SABAP surveys in 1987–1992. It is suggested that the differences in bird species composition are most likely associated with anthropogenic influences including land-use changes and overutilisation of shrublands as grazing for domestic livestock. Ostrich 2008, 79(2): 227–234

Dead shrubs lying on the soil surface in an arid shrubland in the southern Karoo have half-lives of 9 to 18 years depending on wood density which varies among species. Dung pellets of sheep and springbok can remain intact on the soil surface in Karoo shrubland and desert grassland for five years or more. Highlights the results of a study conducted on information on ecosystem processes and their response to land use and climate in arid southern Africa. Illustrates with tables and graphs.Keywords: Aggeneys; Augea; Dead shrubs; Decay rates; Demography; Deserts; Disintegration; Drosanthemum; Dung beetles; Dung pellets; Ecosystems; Galenia; Global standards; Karoo; Litter; Pteronia; Sheep; Shrub breakdown; Soil surface; Springbok; Woody shrubs; wood; dung; arid; rangelands; decomposition; augea capensis; drosanthemum montaguense; galenia fruticosa; pteronia pallens; desert; south africa; shrubsAfrican Journal of Range & Forage Science, Vol. 13, Iss 3, p.89-93

Details of 12 species and 16 species from species splits that are new to the list of birds for Angola are presented. Range extensions and new distribution records for a further 50 species, including 16 species previously considered to have very restricted ranges, are listed and discussed. Mis-identified species, or species for which Angolan records are doubtful, are listed together with reasons why each of the species is unlikely to occur in the country. Several taxonomic issues around some of the Angolan near-endemic bird species are highlighted, together with some discussion on potential species splits. Ostrich 2007, 78(1): 55–63

British Ornithologists' Union, UK172 pages, hardcoverISBN 0 907446 27 2, price £30-00Ostrich 2007, 78(1): 109

No Abstract.Vulture News Vol. 55, 2006: 8-9

No Abstract. Vulture News Vol. 54 2006: 30-33

No AbstractOstrich 2006, 77(1&2): 102–104

Studies in Avian Biology No. 28, Cooper Ornithological Society, c/o Western Foundation of Vertebrate Zoology, USASoftcover, 100 pages, 41 figures, 29 tablesISBN 0-943610-59-1, price $15.00Ostrich 2006, 77(1&2): 112

2003 British Ornithologists' Union, British Ornithologists' Club, The Natural History Museum, Tring, Herts HP236AP, UK e-mail cservs@nbnplymbridge.com 594 pages, 32 colour plates, hardcover ISBN 0 907446 25 6, price £345.00 Ostrich 2004, 75(3): 184185

(Ostrich: 2003 74(3&4): 231-232)

We surveyed the bird species richness and abundance at 12 sites in gardens and four sites in natural woodlands at Prince Albert, Western Cape, South Africa, over a two-month period, from 14 September to 15 November 1999. Bird numbers were estimated using point counts. Of a total of 75 bird species recorded, 34 species occurred in both garden and natural sites, 23 species only in gardens and 18 species only in natural woodland. The sites in natural habitats had the greatest similarity between species. The commonest species nesting in gardens during this study was the Cape Sparrow (Passer melanurus), followed by the Laughing Dove (Streptopelia senegalensis), and Greater Striped Swallow (Hirundo cucullata). Bar-throated Apalis (Apalis thoracica), Namaqua Warbler (Phragmacia substriata), Fiscal Flycatcher (Sigelus silens) and Common Fiscal (Lanius collaris) nests were only observed at the natural sites. Southern Double-collared Sunbird (Cinnyris chalybea) and Cape White-eye (Zosterops capensis) nested in both natural and garden sites. Tree hole-nesting species were rare in both gardens and natural woodland, but this reflects the paucity of suitable sites rather than the rarity of the species per se. With the exception of two sites that lacked nectarivores, all foraging guilds were represented at all sites. There was a marked difference in numbers of insectivorous, granivorous and omnivorous species between the natural woodland sites and the garden sites. The gardens showed a gradient in species richness from the gardens with structurally simple vegetation (bare ground) through to the richest species assemblages in the structurally most diverse habitats (trees). However, this gradient was less clear than expected. Structurally fairly simple vegetation (but abundant ‘flowers') had species numbers almost as high as the woodland sites, and higher than the garden tree sites. (Ostrich: 2003 74(3&4): 209–216)

The behaviour and activities of 6 458 raptors (Accipitridae and Falconidae) and 1 947 Corvidae in the Karoo, South Africa, were recorded during the period January 1988 to June 2000 (n = 208 surveys) over a total distance of 90 012km. A significantly larger proportion of raptors and corvids were recorded foraging in road verges, or flying along roads than foraging or flying over rangelands. About 21% of all observations of crows feeding or foraging were associated with road-kills, whereas less than 2% of observations of feeding and foraging Accipitridae and Falconidae were associated with road-kills. The most frequent Accipitridae feeding on road-kills were Pale Chanting Goshawk (Melierax canorus), Yellow-billed Kite (Milvus migrans parasitus) and Jackal Buzzard (Buteo rufofuscus). There was no seasonal pattern in the number of crows feeding on road-kills, although there was a trend for more mammals to be killed on the roads, and thus more available food, in winter (June). It is likely that Accipitridae and Falconidae are attracted to roads by the availability of perches and the relatively productive road verges rather than the availability of road-killed animals, whereas crows may be attracted by road-kills as well. (Ostrich: 2003 74(3&4): 181–186)

1 In the debate on the stability of savanna vegetation, spatial processes are often neglected. A spatial simulation model based on a cellular automata approach was constructed to identify the factors and processes crucial to the coexistence of trees and grass, and their effects on the spatial arrangement of trees in arid and semiarid savannas. 2 The simulation shows that the traditional key determinants of savannas rain, fire and grazing generate and sustain a coexistence of trees and grasses only under specific conditions. 3 An increase in the rainfall (improved tree establishment) or in grazing (reduced competition from grass), led to an increase in the woody component in the model. Where this trend was reversed by occasional fires, the simulation indicated that trees would be patchily distributed in thickets that excluded fire. 4 For an intermediate range of fire, grazing and rainfall variables this strongly clumped distribution pattern of trees represented a stable tree-grass mixture for more than 20 000 simulated years. 5 The hypothesis is formulated that factors or processes other than competition for moisture, herbivory and fire are needed in addition to induce a long-term persistence of scattered trees. 6 By exploring the long-term and spatial consequences of altering the variables that were thought to be key determinants of savanna vegetation, this spatiotemporal model provides a novel insight into the understanding of savanna dynamics.