摘要:

Summary.In Group (1) we find that in adults the head and body are moulted twice a year, and the wings and tail only once a year,i. e. when moulting from non‐breeding to breeding dress, except with the genusHedydipna, which moults the wings and tail twice a year. The young birds complete their moult, including wings and tail, from first young dress direct to a breeding dress. In Group (2) the adults have a complete moult once a year from a breeding dress to a breeding dress, but the young birds have a complete moult, including wings and tail, from the first young dress to an immature (intermediate) dress, and another complete moult, including wings and tail, from the immature dress to the breeding dress, In Group (3) the adults moult direct from 8 breeding dress to a breeding dress, and the young birds moult, including wings and tail, from first young dress to a breeding dress.It may be remarked that all these three different sequences of plumage are also found in some of the Sunbirds of India, i. e.Cinnyris minimaSykes andCinnyris asiatica(Latham) have non‐breeding dresses, whereasCinnyris zelonica(LinnEus) andCinnyris loteina(Linnsus) do not have a non‐breeding dress, andÆthopyga ignicauda(Hodgson) has an immature (intermediate) dress.Some species no doubt breed during both the long and short rains, and those which appear to have an individual breeding cycle and subsequent moult may he found to fit into these seasons, and certainly some of the recorded breeding months point to this being so; but whether the same birds breed twice in the year seems doubtful.As the British Museum series is mainly evacuated owing to the present emergency this paper must be accepted as being based only on present available material, and we hope to publish more detailed information, especially on the species in Group (4), at a later date.It is interesting to note that the genusChalcomitrahas, as far as we know, no non‐breeding dress, and that the genusAnthrepteshas, so far as we know, no non‐breeding or immature dress. It must also be remarked that whereasNectarinia famosahas a non‐breeding dress throughout its distribution from Abyssinia to South Africa,Cinnyris afterhas no non‐breeding dress in South Africa, but one of its races has a non‐breeding dress in central Africa.The evidence accumulated is by no means conclusive, and there are some species (Group (4)) about which we know very little, either of their moults or breeding, but it has taken us a step further in our knowledge, and we trust will serve as a basis for future workers both in the field and i

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1945.tb02985.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1945.tb02986.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1945.tb02987.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1945.tb02988.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1945.tb02989.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1945.tb02990.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

摘要:

SummaryAn account is given of one hundred hours of observations at a Bateleur'a nest in north‐eastern Tanganyike Territory. The adults were a white‐backed bird and a chestnut‐backed, with a sub‐adult; probably over three years old, in association with them. The youngster took 130 dap to fledge. During at least part of the time all its food was brought by the white‐backed adult. When the fledgling was about one month old its feeds averaged about one in eight hours; during its last week in the nest feeds were nearly three times as frequent.Literature and unpublished data are reviewed in relation to special points of interest, viz.:—Slow development and maturation accords with longevity. Fledging period apparently longer than authentically recorded for any land bird. First wing‐moult may have started before first flight.Tail length is greater in proportion to wing in juveniles than in adults.Proportion of white‐becks to chestnut‐backs differs in parts of Africa, being least in South africa. White‐tailed birds seem confined to Sudanese semi‐desert belt.Voice, flight habits and wing‐noises seem to differ in parts of Africa.Food comprises both carrion and live prey, especially snakes, but not poultry or other birds. Claws are not less sharp than those ofStephanoaëtusandPolemaëtus.Breeding records in Tropical Africa show, when analysed with reference to egg‐dates, that as a rule in each area the young get through their fledging period, or at least the later, unbrooded part, during the local cool dry season.Psychologically the Bateleur is most peculiar: in the wild it is shy of man, sociable with big birdv of its own and other species, and breeding birds tolerate sub‐adults: in captivity it becomes unusually tame, has a grecting ceremony for fr

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1945.tb02991.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1945.tb02992.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1945.tb02993.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1945.tb02994.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY