ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1953.tb00705.x

出版商:Blackwell Publishing Ltd    

年代:1953

数据来源: WILEY

摘要:

SUMMARY.1A brief outline of the topography of British Guiana is given.2The climate of the lowland forest region, which has two wet and two dry seasons, is described. The forest trees flower mainly in the long, and fruit in the short, dry season.3The natural vegetation of the coastland and of the lowland forest region is briefly described.4It is shown that man has effect on bird life only as the agent responsible for forest clearings, and the secondary forest that results from them and from forest fires.5The long‐established and comparatively large clearing at Mazaruni Station is described.6The bird communities of the evergreen forest and of forest clearings, and more briefly those of river, scrub and savanna habitats, are described.7It is shown that the principal breeding season falls in the first half of the year, especially in and at the close of the short dry season. A weak second peak of activity occurs in September. The forest birds are more strictly seasonal than those of clearings. Instances of restricted and special nesting seasons are given.8The breeding seasons of the lowland forest region of British Guiana and of other tropical regions are compare

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1953.tb00706.x

出版商:Blackwell Publishing Ltd    

年代:1953

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1953.tb00707.x

出版商:Blackwell Publishing Ltd    

年代:1953

数据来源: WILEY

摘要:

Summary.1. Recent published and unpublished observations ofPhalaropus fulicariusconfirm the existence of a large wintering area off North‐west Africa, from Cape Blanco to Sierra Leone.2. Published observations in the South Atlantic off South Africa indicate the presence of wintering birds. Some birds have been recorded well inland (probably. vagrants).3. Phalaropes off North‐west Africa seem most concentrated where the plankton is densest. Probably the same holds good for the south, though no great numbers have been seen here yet.4. The parallel of the Humboldt Current off South America lends support to the belief in a wintering area off the C

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1953.tb00708.x

出版商:Blackwell Publishing Ltd    

年代:1953

数据来源: WILEY

摘要:

Summary.1The Asiatic species of the genusSpizaëtusare reviewed. A new subspecies,S. nams stresemanni, is described from Nias Island.2There is evidence, as yet inconclusive, that three species replace one another geographically on the West Sumatran Islands, only one species occurring on any one island

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1953.tb00709.x

出版商:Blackwell Publishing Ltd    

年代:1953

数据来源: WILEY

摘要:

Summary.1The following five races ofC. sovimangaare recognized:C. s. sovimanga(Gmelin), Madagascar (except south‐east) and Gloriosa Island;C. s. apolisHartert, south‐eastern Madagascar;C. s. aldabrensisRidgway, Aldabra Island, Aldabra Archipelago;C. s. abbottiRidgway, Assumption Island, Aldabra Archipelago; and C. s. buchenorum nem‐ race, Cosmoledo Islands, Aldabra Archipelago.2Attention is drawn to birds from Astove Island, Aldabra Archipelago—none of which are available for study—which may prove to be an undescribed race linkingC. sovimangaandC. c

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1953.tb00710.x

出版商:Blackwell Publishing Ltd    

年代:1953

数据来源: WILEY

摘要:

Summary1The species concerned chiefly in this study are those in which the male does not incubate. Among such species the male may show interest in the nest whileitcontains eggs by: standing guard, bringing food, bringing materials of which the nest is constructed, escorting the female on her return to the eggs, and periodic visits of inspection. These contacts, which an individual male may use singly or in combination, are important in preparing him for the discovery of the nestlings.2Standing guard is most common among big, powerful birds, such as jays. Among weaker birds it seems to be chiefly individual rather than specific.3Three types of food‐bringing are distinguished: (1) sustaining, when the male provides most or all of the food for his incubating partner, as in hombills and goldfinches; (2) occasional, when scattered feedings do not materially diminish the time the female must devote to hunting her own nourishment; and (3) anticipatory, when the male brings food for his unhatched offspring rather than for his mate. Rarely a female bird offers food to her unhatched eggs.4Details of the events leading up to and following the male parent's discovery of the nestlings are given for 18 nests of 14 species in 7 families, together with less complete observations for several additional nests. Most of these studies were made in Costa Rim.5Eight male parents brought food within an hour after the first egg hatched; eight in from one to six hours; five in from six hours to 1 1/2 days; one between the sixth and tenth day after hatching.6In no instance did the female parent successfully attempt, by voice or gesture, to inform her mate that the eggs had hatched. At most she could demonstrate to him her own increased need of food. The male was obliged to discover the nestlings for himself; and his promptness in doing so depended as a rule upon the habits he had formed while his mate incubated (see para. 1 above).7If the male had not brought food during the period of incubation, he did not (in the cases adequately studied) come with a morsel until after he had seen the nestlings, the sight of which stimulated this new activity. If he had been bringing food before the eggs hatched he might have a morsel in his bill when he first saw the nestlings, and feed them at once. Among birds of this group it seems likely that the male was in some instances led to carry food to the nest by seeing his mate do so.8Male birds which do not incubate are often impatient to begin feeding. They may bring food and offer it to the unhatched eggs, or attend the nestlings in a neighbouring nest of another species until their own eggs hatch. When they first become aware of their own nestlings they may bring far more food than is needed, and present it again and again to the satiated babies. The female often benefits by this excess food, and may sit more constantly than before the eggs hatched.9In periods of inclement weather, and especially with large broods, prompt feeding by the male may be essential to the survival of the nestlings. In mild weather, and with small broods, his promptness seems tess importan

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1953.tb00711.x

出版商:Blackwell Publishing Ltd    

年代:1953

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1953.tb00712.x

出版商:Blackwell Publishing Ltd    

年代:1953

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1953.tb00713.x

出版商:Blackwell Publishing Ltd    

年代:1953

数据来源: WILEY

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1953.tb00715.x

出版商:Blackwell Publishing Ltd    

年代:1953

数据来源: WILEY