摘要:

SummaryThe reasons for a systematic form of notation of bird‐song are discussed. Though the sound spectrograph will remain the primary tool in any study of bird‐vocalization, there is still a need for a simple, comprehensive notation for the bird‐watcher. This will act as a supplement to the bird‐song recordings now available. After a survey of various attempts at bird‐notation, from syllabic notation to the sophisticated graph‐methods suggested by Stadler&Schmitt, A. A. Saunders and Gladys Page‐Wood, recommendations for a comprehensive notation are made, illustrated by notated examples of song‐phrases from

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1970.tb00090.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

SummaryFour species of African barbets (Lybius torquatus, L. vieilloti, Trachyphonus darnaudii, andT. erythrocephalus) regularly sing in duet. Duets consist of phrases repeated at very regular intervals; inL. torquatusandL. vieillotithe standard deviation is less than a tenth of the mean interval between duet motifs. Sound spectrographic analysis of the songs indicates that an internal rhythmic behaviour pattern determines in large part the temporal features of the duet in these barbets:(1) one member of a pair ofL. torquatuscontinues to call in rhythm even though its mate may call irregularly, (2) in the other three species the calling rhythm of each of the two mates is different, especially inL. vieillotiwhere the ratio of the periodicity of calling of the two birds averages 1:1.52 and where one bird continues to call at the same rate when its mate ceases to call, and (3) several non‐duetting African barbets have regular calling periodicities, some with greater precision than in the duetting barbets and some with less. In the barbets the temporal pattern of duets appears to be in greater degree determined by individual calling rhythms (as in some non‐duetting barbets) than by the auditory reaction time involved in a bird responding to its mate. Duetting in barbets probably functions both in maintenance of a pair bond and in territorial advertisem

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1970.tb00091.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

SummaryWintering Brown Shrikes frequent open lowland country, a habitat that is largely man‐made in Malaya. Individuals are sedentary during the winter season, each occupying a restricted area and exhibiting territorial behaviour.The earliest observations each year in different parts of Southeast Asia indicate that the southward migratory journey is relatively rapid. In Malaya, migrants arrive from the first week of September to the third week of October. At a lowland netting station during 1964–68 a major part of the total catch was taken in the months of September and October. Only a small proportion of these early shrikes wintered in the netting area. No distant recoveries were reported, and the subsequent movements of birds that were not retrapped are unknown.Shrikes netted in September—October comprised 29% adults, 54% full grown (i.e. immatures plus poorly—characterized adults), and 17% juveniles. The mean wing‐length was significantly longer among adults than among both other classes, which did not differ significantly. During the winter, all ages showed a progressive decline in wing‐length until the flight feathers were renewed in a premigratory moult falling in February—early April. Moult recorded in four Brown Shrikes taken in October‐November is interpreted as the completion of a post‐nuptial moult, commenced on the breeding grounds before autumn migration. In April, after the premigratory moult, confirmed adults constituted 70% of the total trapped and apparent immatures 30%.The mean weight of September birds was lower than any other month except November. The low weight in November is partly correlated with the shorter mean wing‐length of the sample; it may also reflect the seasonally unfavourable weather of this month. The mean weight in February was high, although all birds were moulting; the weather in this month is typically hot and dry. Highest weights were recorded in April, indicating the premigratory deposition of fat. Weights of birds trapped more than once at different intervals showed a small initial weight loss (2 g), followed by a recovery within four days and no long‐term adverse effects. A comparison of September weights in Taiwan and Malaya provides a tentative basis for the calculation of fat reserves utilized on the migratory flight.The proportion of returns after one year was 11%, and after two years 1 % only. Most returning birds were present in the netting area during the latter part of the winter of initial ringing; it is suggested tentatively that imprinting of the wintering grounds may occur during this period.Ecologically in Malaya the Brown Shrike occupies a new habitat only gradually being filled by the resident Rufous‐backed Shrike. There is no evidence of interaction

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1970.tb00092.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

SummaryPalaearctic waders were caught and weighed at Lake Nakuru in the Kenyan rift valley on 22 occasions in the non‐breeding season between March 1967 and May 1969. The weights of four species are presented:Curlew Sandpiper, Little Stint, Ruff and Marsh Sandpiper.Winter weights were relatively low and varied little. It is thought that waders had very little fat reserve at this time.The mean weights of early autumn samples tended to be higher than corresponding mean winter weights, and autumn populations included some markedly heavy birds.An increase in the mean weight, and a dramatic rise in the maximum weights of each species occurred shortly before its main spring departure time. The great majority of waders apparently gained considerable weight before migration from the area in April and May.The spring migration of waders from Kenya is briefly discusse

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1970.tb00093.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

SummaryData are presented for the fat and water contents of 410 specimens of 11 species of trans‐Saharan migrants collected on the northwest coast of Egypt in autumn. Mean fat contents vary from 37% of lean dry weight inHirundo rusticato 110% inSylvia communis. There is also much variation in the range of fat contents within individual species,Muscicapa striataandLanius colluriobeing exceptionally closely grouped andP. phoenicuruswidely dispersed. The results for each species are discussed in relation to their migratory circumstances.On the basis that the birds concerned would have started to cross the eastern Mediterranean with at least 11/2 times as much fat as they contained on landing in Egypt, comparisons are made with data for spring migrants in western Africa and with American trans‐Gulf migrants.Water contents, discussed as % of lean dry weight, show considerable variation within each species:the coefficient correlating this percentage with % fat is around 0.50 except inLanius(0.98) andOriolus(0.92).On investigating the relationship between wing‐length and lean dry weight, we did not find a strong correlation in any of the species and caution in accepting conclusions to the contrary is indi

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1970.tb00094.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

SummaryAn account is given of the geography and ecology of the Mollendo district, Southwest Peru, followed by a systematic list of the species recorded there over a period of 16 years' residence.The following species are recorded, apparently for the first time, from the south coast of Peru:Pachyptila belcheri, P. desolata, Florida caerulea, Butorides striatus, Bubulcus ibis, Plegadis chihi, Himantopus himantopus, Micropalama himantopus, Chaetura pelagica, Petrochelidon pyrrhonota, Riparia ripariaandPheucticus chrysopeplus.

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1970.tb00095.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

SummaryExamination of survival rdtes of nestlings and fledglings of some species show that there is a strong tendency for those young which are hatched earliest in the season to have the greatest chance of surviving to breed. Since natural selection so strongly favours parents who leave many surviving young, the question arises as to why other birds breed later than the date at which they could most successfully raise their young.It is suggested that the food supply for the breeding females immediately prior to the breeding season may limit their ability to form eggs and the females may thus not be able to lay at the time which would result in young being in the nest at the best time for raising them, but as soon after this time as the female is able to produce her eggs. Not all species are likely to be prevented, by food shortage, from breeding at the best time for raising young and the groups of birds most likely to be affected are discussed.

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1970.tb00096.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1970.tb00097.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1970.tb00098.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1970.tb00099.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY