ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1952.tb01786.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

Summary.1 Observations on the hour of the day when the eggs are laid are presented for about 40 species of Central American birds; observations on the hour of hatching for about 14 species.2 In a single locality each species has its own time for laying. There are also well marked family trends, to which, however, exceptions are found. Tanagers, finches (with one decided exception), wood warblers, honeycreepers, wrens, and hummingbirds usually lay early, from before to soon after sunrise.Turdus grayilays considerably later. American flycatchers lay consistently later than the tanagers, finches, etc., often waiting until the second half of the forenoon.Manacus aurantiacusand two species ofCrotophagalay around midday; the goatsuckerNyctidromus albicollisrather late in the afternoon.3 Birds which lay about sunrise show less variation in the hour of laying than those which lay later in the day.4 Among birds which lay sets of two, some deposit both at about the same hour, so that the interval between layings is about 24 hours (e.g. tanagers and very small finches). Others lay the second egg later in the morning than the first, so that the interval is 25 or 26 hours (e.g. the larger finchesArremonopsandSaltator). Tioris olivacmwhich has sets of two or three, andTroglodytes musculuswhose set is three or four, both lay their eggs at intervals of approximately 24 hours.5 The hour of hatching, for a given species or in a single nest, is more variable than the hour of laying.6 With flycatchers of the genusMyiozetetes, eggs hatch during the (late ?) night and forenoon, scarcely ever in the afternoon. Apparently there is a diurnal rhythm in the birdling's efforts to break through and escape from the shell.7 With the tanagerRamphocelus passerinii, eggs hatch predominantly in the forenoon, not infrequently in the afternoon, rarely during the night. Here the predominance of hatching in the forenoon may be caused by constancy in the hour of laying and in the length of the incubation period when this is not retarded.8 Among passerine birds, there seems to be a well marked tendency for eggs to hatch in the afternoon far less frequently than would be expected if the distribution of this event were random through the 24 hours of the day. But apparent excep

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1952.tb01787.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1952.tb01788.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

Summary.1 During the summer of 1949 separate expeditions visited the islands of Palma and Gomera in the Canary Islands.2 A survey of the birds was made, mainly of the Passerine species, to determine in which habitats they were found.3 The distributions of some of these species is discussed and, so far as possible, accounted for.4 Of 12 species common to Palma and Britain, five had calls which differed distinctly, while three,Fringilla coelebs, Parus caeruleusandPhyllosropus collybita, were strikingly different.5 A systematic list for the two islands is

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1952.tb01789.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

Summary.The Oyster‐catcherHaematopus astraleguspopulations of western Europe (Holland, South Britain, Fair Isle, Unst and Faeroe Islands) differ very little morphologicallv, but show interesting variations in their distraction displays.These displays, comprising (1) aggressive flight, (2) a furtive run, (3) false‐brooding, (4) pseudo‐sleeping, and (5) lure display, are described, with comments on their regional importance. Aggressive flight, false‐brooding and lure display are more strongly developed in Faeroe than elsewhere. At Fair Isle (and to a less extent at Unst) displacement “ butterfly‐flight” replaces lure display.It is shown that the lure display has evolved as a terrestrial modification of displacement “ butterfly‐flight”, which has proceeded furthest in the Faeroe population, hardly at all in the more southerly populations, and to an intermediate degree among the birds of Unst.The Oyster‐catcher's extension to the Faeroe Islands—probably from the British area, in Comparatively recent times—involved colonization of an atypical moorland habitat. The distraction displays appear to have been perfected in the absence of terrestrial predators other than men and dogs, which have been present for about 1000 years.The remarkable development of these display patterns is probably due to hereditan differences, affecting ethological attributes, which have arisen between the Faeroe and the more southerly populations. It is suggested that their evolution has been stimulated by the psychological effect of frequent disturbance of the brooding urge by man, during the attempt to colonize a new and

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1952.tb01790.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

Summary.1 An account is given of the breeding cycle of the Greater Shearwater, with speciat reference to the colony (estimated at 4,000,000 breeding birds) at Nightingale Island in the Tristan da Cunha group.2 The birds arrive at the breeding grounds during late August and September. There is a brief laying season during the second week of November and the chicks hatch early in January. In April the adults desert their young, when they are full–grown but still in down. Fully feathered juveniles are found at the beginning of May and start flying towards the end of the first week of May. As far as is known the juveniles have all left the breeding grounds by early June.3 Special points of interest relating to the breeding cycle are:.‐(a) The presence of Greater Sheanvaters at the breeding grounds in large numbers at least one–and–a–half months in advance of the laying season. (b) The overcrowding of the breeding grounds at Nightingale. (c) The courtship ceremonies. (d) A strongly developed diurnal habit during the breeding season, although the birds are most active after 4 p.m. (local time) and at night. (e) The presence of large numbers of juveniles at the breeding grounds during May. (f) The apparent absence of adults from their burrows. from mid–April onwards.4 The occurrence of the Greater Sheanvater at the north–easterly limits of its range at the time breeding IS beginning suggests that a proportion of the population fails to breed each year, and that the main return from the north takes place in mid–ocean, and down the west side of the Atlantic, mainly in August.5 Flight and locomotion are described.6 Data collected on the exploitation of this species by the Tristan islanders show that the annual depletions are not more than l% of the estimated Shearwate

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1952.tb01791.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

Summary.1 Personal observations are given on habits, habitat, and notes ofCertlmlauda curvirostris.2 Certain call–notes may be connected with the feeding of juvenals and the keeping together of family parties.3 Breeding cycle is correlated with latitude.4 There are grounds for accepting two forms of Long–bill Lark in South West Africa and all the forms of Long–bill Larks as geographical races of one species, including C.subcoronataSmith andC. falcirostris Reichenow.5 In all, seven geographical races are recognizable in specimens in the National Collection. Other races have been described whose validity has n

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1952.tb01792.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

Summary.Trapping and ringing of non–resident birds in Egypt in 1949 and 1950 are recorded and details of re–trapping after migration and of one foreign recovery are gi

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1952.tb01793.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

Summary.1 The winter environment of Arctic Lapland is described, in so far as it affects the birds.2 The wintering birds are listed, together with their main foods, and the adaptations shown by them are discussed, a distincfion being drawn between “ pre–adaptations” and “specific adaptations”.3 The effect of man on the winter avifau

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1952.tb01794.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

Summary.The birds seen on the Berlengas, the Desertas, Baixo Island, and the Salvages in June and July 1939 are listed and field notes are given on certain species.InPuffinis kuhlii borealisincubation was by both sexes. Where it is unmolested by man, as at Grande Salvage, this bird is partly diurnal in visiting the land; where molested, as on the Berlingas' and Desertas, it is nocturnal.InBulweria bulweriiincubation is by both sexes, probably in shifts of two or more days.At Grande Salvage there appears to be a division of the year into specific breeding seasons by which the maximum use is made of the ground–burrows by two if not three species of petrels. This probable breeding competition is discussed, and other examples suggested from the literature of petrels breeding on small tropical and sub–tropical isla

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1952.tb01795.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY