NOTES ON THE BIRDS OF THE CAPE L'AGULHAS REGION

Gargett, V. 1982. Synchronous hatching and the Cain and Abel struggle in the Black Eagle. Ostrich 53:147-150.

An experiment was conducted to cause two Black Eagle Aquila verrreauxii chicks to hatch synchronously. There was ample food on the nest and the female offered it to both chicks, but the smaller chick, from the smaller second-laid egg, died. The greater reach of the chick from the first-laid egg enabled it to obtain more of the food offered, so that it gained weight. Its greater mass then enabled it to prevent its sibling from taking food. Both chicks showed aggression, but that of the heavier chick was more effective.     

NOTES ON SOME MARSH BIRDS OF CAPE SAN ANTONIO,ARGENTINA*

During an 11-month study of the Black-headed Duck in eastern Argentina, observations were made on the marsh birds of Cape San Antonio, Province of Buenos Aires. These observations supplement the distributional and life history obtained by Gibson (1879–1920), Wetmore (1926) and others. The deep, fresh-water marshes characteristically are dominated by one of three plants: tules, cutgrass or cat-tails. There were surprisingly few marshes with mixtures of these plants and few marshes which showed a gradual transition from marsh to uplands. Marsh birds showed considerable adaptation in chronology of nesting and nest-site selection for the seasonal water cycle of wet springs and dry periods in the late summer and fall. Some marsh birds were involved in nesting over a longer period than is usual in Northern Hemisphere marshes. As seems characteristic of all marsh birds, cover-water edges were usual sites for nests. There were only a few species with restricted nest-site selection, and competition between closely related species was noted only among the three species of coots. A list of the marsh birds of the area is given, and comments are presented on the ecology and behaviour of selected species.     

SOME NOTES ON THE BIRDS OF THE ISOKA DISTRICT OF THE NORTHERN PROVINCE OF NORTHERN RHODESIA

Dean, W. R. J. 1978. Moult seasons of some Anatidae in the western Transvaal. Ostrich 49:76-84.

Spurwinged Geese Plectropterus gambensis, Egyptian Geese Alopochen aegyptiacus, Yellow-billed Ducks Anas undulata, Redbilled Teal A. erythrorhyncha and Southern Pochard Netta erythrophthalma have a flightless moult mainly during the dry season, from April to August, in the western Transvaal. South African Shelduck Tadorna cana moult during October to February after breeding during July and August. The Cape Shoveller Anas smithii has two main flightless periods, April-May and October-January. Cape Teal A. capensis have been recorded in flightless moult in October, December and January.

The duration of the flightless period correlates with wing length; larger and longer winged Anatidae require proportionally more time for wing moult than do smaller and shorter winged Anatidae.

Geese and shelducks moult on large open lakes with an open shore. Ducks have been recorded flightless on lakes and dams, with or without emergent vegetation.     

THE BIRDS OF BLYTHSWOOD AND SOME NOTES ON BIRDS OF THE DISTRICT

Wintle, C. C. &; Taylor, P. B. 1993. Sequential polyandry, behaviour and moult in captive Striped Crakes Aenigmatolimnas marginalis. Ostrich 64:115-122.

Captive Striped Crakes showed sequential polyandry, the female laying for a second male when the clutch of her first mate was about to hatch. Where aviary space permitted each male set up a breeding territory and each female defended a larger area encompassing the territories of one or two males. Non-territorial subordinate males and females did not breed. The female initiated breeding by attracting the male and soliciting copulation, and the male incubated the eggs and cared for the young. Incubation took 17–18 days, the chicks left the nest at 4–5 days of age and were fully grown and capable of flight at 46–53 days. Breeding occurred from September to March and males normally reared two broods per season. Territoriality was evident only during the breeding season. Juvenile plumage was a duller version of the sexually dimorphic adult plumage; post-juvenile moult bean at 13–15 weeks and was complete at 21 weeks. Remex moult was simultaneous and a complete moult regular1 occurred twice a year in adults, in December and April (males) and September and March/April (females).     

SOME NOTES ON THE BIRDS OF THE KAOKOVELD

Whitfield, A. K. &; Blaber, S. J. M. 1978. Feeding ecology of piscivorous birds at Lake St Lucia, Part 1: Diving birds. Ostrich 49:185-198.

The diets of three species of diving piscivorous birds at Lake St Lucia, Natal, South Africa during 1975 and 1976 are described and related to availability and abundance of different prey species. Mugilidae and Clarias gariepinus were the chief prey of the Fish Eagle Haliaeetus vocifer, while Johnius belengcrii and Sarotherodon mossambicus were, respectively, the main food items of Caspian Terns Hydroprogne tschegruva, and Pied Kingfishers Ceryle rudis. The methods of prey capture used by the three species of birds are described.

Predation on particular species of fish was related primarily to their swimming depth, abundance, size and distribution in littoral areas. Fishing habits, densities and foraging periodicity of the birds are discussed with regard to physical parameters such as thermals, wind speeds and water turbidity. The timing of breeding seasons at Lake St Lucia is related to fish densities, lake levels, turbidity of the water and air temperatures.     

FIELD NOTES ON THE BIRDS OF KOREA

Notes are given on 78 species of bird recorded in Korea between 7 July 1953 and 14 October 1954, including Temminck's Stint Calidris temminckii and Fantail Warbler Cisticola juncoides apparently recorded for the first time. A further 67 species were also seen.     

NOTES ON THE BIRDS OF EASTER ISLAND

Information on the occurrence and breeding status of sea-birds at Easter Island has long been scanty and incomplete. In order to obtain accurate information and in particular to investigate reports of a supposed breeding site of a "brown-plumaged petrel", we spent three weeks on the island, including 12 days camping out on the uninhabited, waterless islet of Motu-Nui.
The petrel proved to be the Christmas Island Shearwater Puffinus nativitatis , whose breeding range is thus extended by nearly 2,000 miles. Ten other species of sea-birds were definitely identified and specimens, photographs and breeding records were obtained for most of them. It is shown that the bird species frequenting Easter Island are, like the human inhabitants, predominantly of Polynesian origin—in fact the American continents are not represented at all.
The paper opens with a brief outline of present-day conditions on the main island, and concludes with an account of the "bird-cult" rituals which are known to have been a feature of life in Easter Island for centuries.     

NOTES ON THE BIRDS OF SOUTH-EASTERN NIGERIA.

A systematic account (with field-notes) of the birds of south-eastern Nigeria is given, based on a collection of about 350 skins made between 1946 and 1949, mainly in the neighbourhood of Owerri. The range of several species is extended by new Nigerian records and the distribution of the races of other species more clearly defined.     

NOTES ON THE FOOD OF SOME RHODESIAN BIRDS

Borrett, R. P. 1973. Notes on the food of some Rhodesian birds. Ostrich 44: 145 148. 26 stomach contents of Rhodesian specimens of the following bird species were analysed: Accipiter minullus, Vanellus coronatus, Glaucidium perlatum, Cursvrius temminckii, Caprimulgus fosxii, Apus coffer, Merops superciliosus persicus, Mirafra africana, Anthus trivialis, A. similis, Macronyx capensis, Salpornis spilonota, Lanius collurio, and Lamprotornis mevesii, the biggest series being that of A. similis. Points of interest are noted as appropriate.