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1.
R. A. Jubb B.Sc. 《Ostrich》2013,84(3):162-164
Cyrus, Digby P. 1986. Seasonal and spatial distribution of Redheaded Quelea (Quelea erythrops) in South Africa. Ostrich. 57: 162–169.

There are 48 records of Redheaded Quelea Quelea erythrops occurring in South Africa. Most are for the summer and early autumn months from October to April and all are restricted to the low lying eastern coastal areas. The pattern of occurrence in South Africa is similar to that in adjoining countries to the north; the species does not however occur as regularly in the south. Breeding or attempted breeding has been recorded on six occasions. This shows the typical pattern of occurrence of a species at the southern limit of its distribution.

There is some evidence to suggest that its occurrence may be associated with “wet” years when rainfall is above average. The Redheaded Quelea may be considered as a rare and irruptive summer vagrant to South Africa, which only breeds when conditions are suitable.  相似文献   

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D. M. Skead  H. D. Brandt 《Ostrich》2013,84(4):228-230
Griffiths, A. M. 1982. Reactions of some seabirds to a ship in the Southern Ocean. Ostrich 53:228-235. The reactions of 31 species of seabirds (mainly Procellariiformes) to a moving and a stationary ship were investigated in the Southern Ocean. Birds were categorized according to the distance at which they were seen from the moving ship. The proportions of individuals of each species following the ship, as opposed to flying past it, were calculated. Few species allow accurate censuses of their abundance. The time spent following by individual birds is discussed with respect to “turn-over rates” of ship-following species. Species strongly attracted to the ship were scavengers. Food is believed to be the prime factor influencing the attraction of seabirds to ships, although albatrossesMayhave followed to use air currents generated by the ship. Within an hour of the ship stopping most species had increased in abundance. The implications of assessing avian abundance and biomass from a stationary ship are discussed.  相似文献   

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Gervas Clay 《Ostrich》2013,84(2):76-97
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.  相似文献   

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H. H. Hamling 《Ostrich》2013,84(1):9-16
Maclean, G. L. 1974. The breeding biology of the Rufouseared Warbler and its bearing on the genus Prinia. Ostrich 45: 9–14.

The Rufouseared Warbler Prinia pectoralis, a common species of the Kalahari scrub, nests after rain at any time of the year. Nest construction and nest sites are described. The clutch is normally three or four eggs. Incubation takes 12 to 13 days and the nestling period is 11 to 13 days. Data suggest that the Rufouseared Warbler is not a member of the genus Priniu, the generic position it currently occupies.  相似文献   

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《Ibis》1953,95(1):38-69
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.  相似文献   

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《Ibis》1954,96(2):173-206
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《Ibis》1950,92(1):84-94
Notes are based on a collection of 700 skins. Extensions of range include Trachylaemus p. togoensis, Prodotiscus i. flavodorscdis, Campethera n. nivosa, Bleda canicapilla, Phyllastreplms i. icterinus, Pedilorhynchus c. aximensis, Sylvia bnrin, Apalis c. caniceps, Macrosphenus concolor , and Spermophaga h. togoensis recorded from Nigeria and Apus c. strenbelii from West Africa for the first time.
Taxonomic points include reasons for regarding Centropus epomidis as a colour phase of Centropus senegalensis and Sylvietta flavixentris nigeriae as a synonym of Sylvietta flainventris.
Dates of breeding are given for many species, and nests and eggs arc described. Indicator indicator was found in the nest of Hirundo setnirufa.
The chick of Porphyrio alleni is described.  相似文献   

15.
E. M. Cawkell  R. E. Moreau 《Ibis》1963,105(2):156-178
Recent observations in The Gambia have shown that the status of many species has changed in the last forty or fifty years and have provided data on the local breeding seasons for a number of birds. Several species have been found for the first time in this part of West Africa. The various birds concerned are given in a systematic list, together with notes on all the Palaearctic migrants so far recorded from The Gambia. Organized research is recommended on several lines: on the sequence of food sources, especially through the long and severe dry season, when Palaearctic birds are added to resident and when some African species breed. The bird ecology of the mangroves remains to be worked out, and also the relative importance to birds of cleared ground and untouched "bush" at all seasons.  相似文献   

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《Ibis》1960,102(4):618-619
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17.
The Aquatic Warbler is a threatened Afro-Palaearctic migrant with a largely unknown distribution in the winter (non-breeding) season. Protection of wintering sites may be crucial for the conservation of the species. Previous studies have identified extensive areas of north-western sub-Saharan Africa that could potentially be occupied by the species during winter. However, these studies have not necessarily differentiated between potentially suitable and unsuitable habitat types at a spatial resolution appropriate for targeting field surveys. To identify specific sites that could be occupied by non-breeding Aquatic Warblers at a scale appropriate for targeted field surveys, we adopted a modelling approach that combined recent sightings from Djoudj, Senegal, with land cover and climate data. We produced maps of potential distribution using three maximum entropy models. While a paucity of sightings prevented a full test of these maps on independent records, the areas that were predicted to be potentially occupied included areas around which there are historical records. We suggest field surveys should be targeted towards sites in the Inner Niger Delta and a number of marshes along and away from the Niger River in Mali, and to sites in southern Mauritania.  相似文献   

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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.  相似文献   

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