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D. A. Byron 《Ostrich》2013,84(4):174-176
Milewski, A. V. 1978. Diet of Serinus species in the southwestern Cape, with special reference to the Protea Seedeater. Ostrich 49:174-184.

The diet of the Protea Seedeater Serinus leucopterus was assessed by opportunistic observation of feeding occasions throughout the distribution of the bird. The Protea Seedeater feeds mainly on seed of a wide range of plant species. It takes the large seed of Proteo more frequently than it does any other food item. The diet of the Protea Seedeater consists essentially of food items and types similar to those taken by six sympatric and partly sympatric congeners, which are also mainly dating. However, its diet differs quantitatively, each species taking different food types, such as achenes and seed kernels, with different frequency.  相似文献   

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《Ibis》1958,100(1):59-66
1. The submissive display is described. It is sometimes given when the bird appears to be simultaneously frightened and attracted by a fellow member of the species.
2. The pairing behaviour of some individual captive birds is described. Some degree of mutual fear and hostility seems to be a necessary correlate of sexual attraction in this species. Birds that know and are at ease with one another do not pair.
3. A young male showed (in autumn) behaviour similar to that of a female ready to pair when introduced to an old and aggressive male. A possible biological function of such behaviour is suggested.  相似文献   

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T. Farkas 《Ostrich》2013,84(3):122-127
Martin, A. P. &; Baird, D. 1987. Seasonal abundance and distribution of birds on the Swartkops estuary, Port Elizabeth. Ostrich 58:122-134. Counts of estuarine birds were made on the Swartkops estuary, Port Elizabeth, between September 1983 and August 1985. Seasonal variations in the numbers of both migrant and resident species were investigated; in the austral summer, over 4000 birds were recorded, whereas in winter, fewer than 1200 birds were counted. Five species made up 74% of the total number of birds: Kelp Gulls Larus dominicanus (21%), Grey Plovers Pluvialis squatarola (21%), Whimbrels Numenius phaeopus (12%), Common Terns Sterna hirundo (10%) and Curlew Sandpipers Calidris ferruginea (10%). The majority of birds (92%) were recorded on the intertidal mud and sand, and a positive correlation was found between bird density and the biomass of a major prey species, Upogebia africana. The avifauna of the estuary has changed considerably since the beginning or this century, probably reflecting long-term trends in the bird populations.  相似文献   

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Wire-worms rarely occur in permanent arable land in sufficient numbers to cause serious damage to crops. Various workers (e.g. Roebuck, 1924; Hawkins, 1936; Miles & Cohen, 1941) have noted the reduction in numbers of wireworms in successive years on ploughed-out grassland. At Rothamsted reductions of 62 % in one year and 85 % in two years were recorded on plots on Highfield. This reduction is certainly due in part to the exposure of wireworms to their natural enemies and to the direct effect of disturbance by implements of cultivation. It has also frequently been suggested that the beetles prefer to oviposit on grassland or clover leys and to a lesser extent on cereal crops (Bryson, 1930; Rawlins, 1934; Balachowsky & Mesnil, 1935; Miles & Cohen, 1938). A laboratory experiment to test this point was accordingly carried out in June 1940.  相似文献   

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Von Maltitz, F., Schmitt, M. B., &; Biggs, H. C. 1984. Measurements, moult and abundance of the Lizard Buzzard in the Transvaal. Ostrich 55: 177–181.

During a 12-year study 51 Lizard Buzzards Kaupifalco monogrammicus were captured in the Transvaal. South Africa. They occurred sporadically, with peaks in the years 1972, 1975, 1979 and 1983 and were significantly more common in winter. Moult was completed between January and June. Mass is given and recaptures documented.  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   

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