摘要:

Summary.1The Strigiformes and Charadriiformes tend to be more persistently active in continuous daylight than the Falconiformes.2In Lapland at midsummer passerine song reaches a minimum a few hours before midnight and a maximum in the hours immediately following midnight. The song‐lull cannot be equated with the quiescent period.3The quiescent period of three species, studied at the nest, the Willow Tit, Fieldfare and Dipper, occurs at different times.4There is evidence that the nestling period of some passerines is shorter in the arctic than in lower latitudes‐suggesting,ceteris paribus, an inverse relationship between length of the nestling period and length of daylight.5Light appears to be the dominant external factor governing bird activity in the arctic.6The coloration of many species is correlated with the extent to which they are active in dim light. The continuous daylight of the arctic summer accentuates the adaptive value of cryptic coloration to open‐nesting birds vulnerable to predatory

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04108.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.1The diurnal rhythm of various activities in three species of sea birds was studied in the island of Jan Mayen (lat. 71oN.) in July and August 1950.2The number of Fulmars flying past a certain point decreased strongly around midnight in July and even more markedly in August.3In Brünnich's Guillemot the number of birds alighting at a colony fluctuated but it was uncertain whether the fluctuations were regular or not.4On the other hand the number of young of the same species leaving their nesting ledges showed a very marked peak during the hours preceding midnight. This peak coincided with a peak at the same place in the numbers of Glaucous Gulls, which preyed on the young guillemots as they flew down to the water.5The amount of sleeping and preening by Kittiwakes at a nesting cliff fluctuated little during the 24 hours in July (when they slept about 7 hours a day) but more in August.6The “ultimate factors” responsible for the rhythms observed in Jan Mayen are discussed.7The duration of sleep is discussed for the birds studied, and compared with that of other spe

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04109.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.1A collection of 2000 skins made in southern British Cameroons during twenty‐six months there from 1949 to 1951 is described. The range of many species is extended.2Field notes are given on forms whose habits were previously unknown or little known and the nidification of several is described for the first time.3Sarothrura pulchra batesiandGymnobucco calvus majorare regarded as invalid.4Malaconotus perspicillatusis regarded as a synonym ofMalaconotus monteiri.5Geographical variation in colour inFrancolinus squamatusin West Africa is described.6The nestling or chicks of the following are described:‐Sarothrura elegans reichenovi, Turacus macrorynchus verreauxi, Phyllastrephus poensis, Hirundo nigrita, Heterhyphantes m. melanogaster, andSitagra monacha.7The immature dress of the following is described:‐Micropus batesi, Phyllastrephus poensis, Dyaphorophyia concreta kumbaensis, Turdus n. nigrilorum, Alcthe poliothorax, Seicercus herberti camerunensis, Chalcomitra ursulaeandAnthreptes seimundi

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04110.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.1Observations are given on spring and autumn migration and cold‐weather movements as seen in the Çatalazi Valley, on the Black Sea coast 200 miles east of the Bosphorus.2The Systematic List gives the status of all the birds seen in this valley, together with other field observatio

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04111.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.1The biology of the Cape Wagtail, supplemented by data collected from the study of a partial albino female, is described. The pairs have territories which they would appear to hold for years, the partial albino having been around the same farmstead for about eleven years.2The main breeding season is from August to November but may extend through the summer. The male presents nest material to the female.3The partial albino female had a song not shared by the male.4She laid eight clutches (Sept. 1947‐Aprit 1948), the incubation periods of which ranged from 13½ to 14½ days.5Nestling period ranged from 14 to 18 days.6Roosting may be communal or in pairs.7The species is parasitised by the Diederick Cuc

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04112.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.1Thepurpuratusspecies‐group of the genusPtilinopusincludes, besides the species listed by Ripley and Birckhead (1942),P. pulchellusandP. superbus,2The peculiar Fijian speciesP. perousiiis more closely related toP. superbusthan to any other member of the species‐group. In cqmparison withP. superbusit shows a simplification of colour pattern and loss of protective colouration in the male, which is to be expected of a species evolving in the absence of close relatives and under the influence of only a low degree of visual predation.3The trends of colour‐pattern seen inP. perousiiare shown to an even greater extent by members of theluteovirensspecies‐group, which have lived under similar conditions, but for a long

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04113.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04114.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.The communal display of the House‐sparrow is described. The display may involve from two to ten or more males, but only one female. In both Hampshire and Holland the display is most frequent in April, uncommon at the beginning of May, rises to a secondary maximum at the end of May, does not occur in August and the first half of September, and reappears in the late autumn.The initiation of the display and the relationship of the birds taking part is discussed. In the instances observed only one bird of each sex was involved in the initial stages. In all cases where the participants have been identified the females have been paired birds. The males have included both paired and unpaired birds; the mate of the participating female has frequently taken a prominent role.It is suggested that the display arises when a male attempts to mount a female which is not ready for coition. A chase takes place, attracts other males and the communal display develops. The occurrence of the display is then related to the sexual relationship between paired birds. It is concluded that the communal display in the House‐sparrow is a true sexual display, which has developed in a social species into a communal display, whereby not only pairs of birds but the whole of the flock may be brought into breeding condit

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04115.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.Wild birds whose eggs ark used for food belong mainly to large species and to those nesting colonially; in general, the eggs of such birds are both accessible and palatable. Charadriiformes are the most important egg‐birds‐both as regards total annual crop and number of species utilized. Charadriiformes and Anseriformes together comprise 85 (or about 60 per cent) of the species which have more or less extensively been exploited during the present century. Procellariiformes and Sphenisciformes are also important.The various species are considered in relation to the estimated annual egg‐crop and the chief localities of exploitation: in terms of yield,Sterna fuscatatakes pride of place, with an estimated crop in excess of 1,000,000 eggs; while species for which the cropping rate may lie between 1,000,000 and 100,000 eggs includeSphsniscus demersus, Pufinus temirostris, Gallus gallus, Gallinula chloropur, Vanellus vanellus, Larus argentatus, L. ridibundus, Sterna paradisaea, Anoiis stolidus, Uria lumvia and U.

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04116.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04118.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY