摘要:

SUMMARYThe behaviour and voice of the blue waxbillsUraeginthus ongolensis, U. bengalusandU. cyunocephalusstudied in captivity are described and composed. Most of the calls are homologous and similar, if not identical, but the songs and alarm calls of the three differ in sound. Feeding, agonistic and reproductive behaviour are described.Cyanocephalusbows its head further forward in the Stem Display, this difference being correlated with its blue crown. Minor differences of behaviour and the apparently less competent sexual recognition ofangolensismay be correlated with its lesser degree of sexual dichromatism. The parental behaviour is essentially the same in all three forms. After fledging, young are recognized individually and strange young are not fed, except (rarely) by individuals with no young of their own. In three cases of adoption the common factor was that the adopting individual was sexually attracted to one of the real parents of the young. The taxonomy of the three species is briefly discussed.

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1965.tb07310.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

SUMMARYRadar observations through one autumn in Aberdeenshire are described showing that more migration takes place in anticyclonic weather than transitional weather, and even less migration takes place in disturbed weather. More migration is detected by radar with following winds than with opposed winds.Comparison of data collected in Norfolk and Aberdeenshire during one season at each shows that more migration is detected by radar in Norfolk, and westward movements, which are a feature of migration into Norfolk, appear in Aberdeenshire only when birds are first drifted northwards.Dawn ascent and reorientation movements of birds in the northern North Sea are described, showing that changes in heading were consistently between S.W./S.S.W. and S.S.E. during the autumn studied.Weather data, radar data and ground observer data from Aberdeenshire and the Isle of May Bird Observatory were analyzed and show again that the normal migration pattern is to fly high with following winds and low only with opposing winds as in Norfolk. However, the weather in Aberdeenshire was more disturbed than it had been in Norfolk, with the consequence that weather factors, other than wind, which affect the normal migration pattérn were found to be much more common

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1965.tb07311.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

SUMMARYA study of the breeding biology ofQuelea queleain Nigeria, and particularly at a large breeding colony near Lake Chad, showed that losses of eggs and young were extremely small. 95% of eggs laid hatched successfully, and 87% give rise to fledglings. Nestling deaths were density‐dependent and apparently due to starvation.The incubation period was 10 days or less. By day, eggs were heated to 34°‐ 37° C. by the sun; at night the females incubated. The nestlings were initially fed mainly on insects, their diet gradually changing to one of seeds—mostly of the grassEchinochloa pyramidalis. The deep body temperatures of young birds were determined. It is suggested that the nestlings left the nest after, on average, 111/2days to escape intolerable temperature conditions in the nest.Fat reserves were accumulated by nestlings and fledglings, and were utilized when the young became independent. The adults put on fat during the incubation period and lost it during the time spent feeding nestlings.It is concluded that the most common clutch‐size ofQ. quelea, which is everywhere three, corresponds to the largest number of young the parents can normally nourish. This conforms to Lack's theory on the significance of clutch‐size, and gives no support to Skutch's opinion that the theory does not apply to tro

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1965.tb07312.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

SUMMARYSeveral resident passerine species of birds on the Tres Marias islands, Mexico, are in a fatter condition than their mainland counterparts just prior to, and at the beginning of, the breeding season. At least two non‐passerine species on the islands are also fat at this time of the year. The significance of the fat reserves of the island birds is discussed, and it is concluded that the fat may serve the functions of energy‐storage and possibly water‐storage, to be used later at the climatically most unfavourable time of the

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1965.tb07313.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1965.tb07314.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1965.tb07315.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1965.tb07316.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1965.tb07317.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1965.tb07318.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1965.tb07320.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY