ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04125.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.tb04126.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary1New Zealand Blackbirds tend to be bigger than British.2The ratio of males to females was 2: 1 and of first‐winter males to second‐winter or older males 4–6: 5‐4 in a normal winter population.3The moulting season at Dunedin was January to April inclusive, but some first‐year birds had a partial moult in August, September and early October.4Plumage of females is classified into five colour‐groups; most birds were “darkish brown”.5The black beaks of first‐winter males change to orange by the end of August; beak‐colour of second‐winter or older males is considered to be a variable genetical character.6Seasonal variation in size of gonads, and its relation to behaviour, are discussed.7Songs and calls are described and related to behaviour. The total song‐period in New Zealand is 10½ months.8Territory is established in the Dunedin area in April and averages 1^ to 2 acres.9Pair‐formation takes place before July and full song plays no part in this.10The roosting site for an individual was constant whether the site was in the territory or not. Roosting and awakening times averaged 20 minutes after sunset and 43‐5 minutes before sunrise.11Nesting begins in late August in New Zealand and ends in late December. Resumption of breeding after desertion is discussed.12The rhythm of activity at the nest during incubation and the relationship of the males to the nest and to the incubating female are described.13Fertile eggs lost approximately 0–1 gm. weight per day of incubation. Nestlings increased in weight, from hatching to maximum, by 13‐3, 11‐2 and 11‐8 times respectively, and decreased in weight before leaving the nest.14Fledging success was lower in the New Zealand nests

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04127.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.1A study was made of Graceful WarblersPrima gracilisin Lower Egypt during 1949 and 1950, particularly of a community of five pairs in a nursery garden at Fay id (Canal Zone).2The Graceful is a bird of low vegetation and feeds on or near the ground. Adults remain paired throughout the year and live in the same plot of ground which is defended against other Gracefuls only during the reproductive cycle. There are two moults a year, before and after reproductive activities which extend from late January to November. During this time at least three broods may be reared.3At the beginning of the reproductive cycle the male's mouth and bill darken and he begins regular song, the territories now become re‐established by song and, when necessary, by display and attack. The average size of territory at Fayid was 2750 sq. yards.4The common displays of the male in the reproductive season are “bowing” and “wing‐snapping”, both being probably derived from locomotory intention‐movements. Song, a threat‐note (“jilting”) and a pure intention‐movement (“flicking”) are associated with the two displays, which are thought to be primarily aggressive. “Wing‐fanning” is a less frequent male display.5Sexual behaviour is described. The female “retires” from the male's company just prior to the copulation period. In her absence he builds. She assists later, and both birds continue throughout incubation.6Three to five eggs make up a clutch in Lower Egypt. A seasonal rise and fall in clutch‐size is indicated. Both sexes incubate in short spells (longest recorded 16½ minutes). In very hot weather at one nest the eggs were covered only 9% of observed time. The incubation‐period is about 11–12 days.7Some numerical data on parental attention are given. The nestling‐period is about 13–14 days. The development and behaviour of the young are outlined. Often the male tends the juveniles alone when the female is, presumably, preparing for another brood.8Reactions towards man and other predators are outlined and discussed in

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04128.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.tb04129.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary11500 weights of tits were obtained in the winter 1951–52 and in November and December 1952.2On average the birds weighed least in the early morning and most just before going to roost in the late afternoon. The increase in weight slackened off around mid‐day, corresponding with a decrease in feeding.3The average weights were inversely correlated with air temperature, owing to increased feeding on cold days.4Blue, Great and Coal Tits were on average heaviest in December (or possibly November) and weights then fell gradually.5It is suggested that the increase in weight by passerine birds in early winter is an adaptation for a potential shortage of food la

ISSN:0019-1019    

DOI:10.1111/j.1474-919X.1954.tb04130.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.tb04132.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.tb04134.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.tb04135.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.tb04138.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY