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R. E. Moreau. 《Ibis》1950,92(3):419-433
1. All the available data, largely unpublished, are assembled for sea-birds breeding in African waters, about 36° N.-36° S.
2. An ill-defined breeding season by any species at any station is exceptional.
3. North of the Equator practically all sea-birds breed in spring or summer.
4. South of the Equator there is much more variation. Round the Cape there is a good deal of mid-winter breeding, mainly in stations affected by the warm Agulhas current.
5. On the east coast most of the breeding takes place in the period June–August from the Gulf of Suez (27° N.) to the mouth of the Zambesi (19° S.) and beyond, i.e. in the hottest months north of the Equator and the coolest months south of it.  相似文献   

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M. J. F. Jarvis 《Ostrich》2013,84(4):211-216
Summary

Randall, R. M., Randall, B. M., Cooper, J. &; Frost, P. G. H. 1986: A new census method for penguins tested on Jackass Penguins Spheniscus demersus. Ostrich 57: 211–215

A census method for Jackass Penguins based on their moulting cycle is described. Population estimates were substantially higher with this method than with total counts, but were not dissimilar to maximum estimates obtained from strip counts. The moult method estimates the size of the entire population and is independent of the breeding cycle and breeding status of both individuals and population. It is not plagued by the problem of absenteeism encountered during most phases of the penguin annual cycle and is independent on their diel activity. The drawbacks to the method are that it is laborious and protracted, that it does not differentiate between the breeding population and the whole population, and is unsuited to some species and some habitats.  相似文献   

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Short, L.L. &; Horne, J. F. M. 1980, Vocal and other behaviour of the Green Barbet in Kenya. Ostrich 51:219–229.

Brief field studies of the Green Barbet Stactolaema olivacea in coastal Kenya, with emphasis on vocalizations, document its social behaviour, including communal roosting of four birds in a cavity. Green Barbets are aggressive, interacting strongly with a number of species. Erecting of the crown feathers, cocking of the tail, and woodpeckerlike swinging movements characterize displays. Wing Flutters and audible Bill Wiping are visual-auditory displays. Vocalizations include the Grating Call, Kek Call, Chuk Call and Chowp Call. These are agonistic and agonistic-reproductive in function. The Chowp Call comprises the song, used in simultaneous singing and duetting.  相似文献   

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Four ringing stations of the SE European Bird Migration Network in Egypt (at the coasts of the Mediterranean and Red seas, in the Nile Valley, and at the northern edge of the Sahara) provided data on birds resting in adequate habitats. At three stations more birds per day were caught in spring than in autumn. Deviating geographical conditions induced high capturing numbers at the Red Sea coast, particularly in autumn. Differences between spring and autumn may indicate loop migration and/or seasonally differing flight or resting strategies. Wing-length distribution may indicate passage of different populations through Egypt. In autumn, birds with low fat scores were caught in high proportion after the crossing of the Mediterranean Sea, while average fat scores increased in birds approaching the edge of the Sahara.  相似文献   

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J. M. Winterbottom 《Ostrich》2013,84(3):236-250
Winterbottom, J. M. 1975. Notes on the South African spscies of Corvus. Ostrich 46:236-250. The three indigenous species of Corvus in South Africa are compared in respect of geographical and ecological distribution, status, breeding, food, economic importance and general habits. Apart from the limitation of range in albicollis by its nesting requirements, it is extremely difficult to pin-point any factors in which the species so differ as to explain the paradoxes of their distribution.  相似文献   

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