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A. A. Kistchinski 《Ibis》1975,117(3):285-301
Studies were made in 1970 in the Chukotski Peninsula, in 1971 in the delta of the Indigirka river and in 1972 in the delta of the Yana river. Grey Phalaropes inhabit polygonal and tussocky moss-sedge tundra rich in swamps, lakes and (in June) temporary ponds. Population density in favourable habitats may reach 1–2 pairs ha-1. Data on breeding chronology are presented, and various aggressive and courtship displays described. Most phalaropes seem to keep within a home range, sometimes large, during courtship time, but no defended territories and no forms of territorial behaviour exist. Many birds, both local nesters and wanderers, can feed on any pond. Sexual dimorphism is described. In 1970, three non-breeding cock-plumaged females were taken. Pairs are formed both before arrival and on the nesting grounds. All courtship displays are wholly or mostly initiated by females. In 1971, in the Indigirka delta, all the Grey Phalaropes were paired by 12 June, and stayed in pairs until the end of egg-laying. In 1970, on the northern Chukotsk, phalaropes seemed to form no (or very few) permanent pairs. Throughout June, most birds occurred in mixed flocks constantly moving between lakes or ponds. Copulation seemed to be promiscuous within the local population; polyandry cannot be excluded in some cases. Pairs appeared to be created only for the time of egglaying; probably, the only biological role of pair-formation is to find a male for incubating. Thus, a definite social system is not a species-specific feature; it can vary depending on local and yearly situations, including probably sex ratio. Nests are usually situated in very wet places, sometimes on the water edge. They can be found as little as 3 m apart, but are usually 40–80 m apart, or further. Incubation begins after the second or third egg. After the end of egg-laying, males drive females away from the nests, and pairs break up. Females and non-breeders gather in flocks and move onto the lakes of maritime tundra, and later on to the sea. The composition of the flocks is not constant: they often join together or part. Brooding males feed near their nests, sometimes in groups; not unfrequently they join flocks of females and non-breeders for some time. The normal average clutch-size is c. 4 eggs; when nesting was delayed (in the central Indigirka delta in 1971) the average was 3–61. The loss of nests was great in 1971; numbers of young on 1–3 August was 10 times lower than adult numbers in June.  相似文献   

3.
Mrs. J. A. Scott 《Ostrich》2013,84(3):201-207
Scott, J. A. 1975. Observations on the breeding of the Woollynecked Stork. Ostrich 46: 201–207.

Little is known about the breeding of the Woollynecked Stork Ciconia episcopus in Africa. This paper discusses breeding, adult and nestling behaviour, nests and sites. Seasonal movements are discussed briefly. Eight nests were studied during 1970 to 1974. At one nest incubation was established at 30 to 31 days and the fledging period 55 to 65 days. No feeding of the young was observed at any time, though one eight hour observation period was undertaken. Few mating displays were seen and none away from the nest.  相似文献   

4.
Barbara K.  Snow 《Ibis》1966,108(2):265-280
From 25 September to 8 October 1963 daily observations were made on a group of Flightless Cormorants Nannopterum harrisi nesting on the west side of Albemarle Island in the Galápagos. Flightless Cormorants are apparently bottom-feeders, and confined to shallow coasts at the western end of the Galapagos Archipelago where there is an upwelling of cold nutrient-rich water. There is no reason to suppose that they are declining in numbers. Males are very much larger than females, the size difference between the sexes being greater than in other species of cormorants. Courtship behaviour, nest-building and mating are described. The earliest phases of courtship take place on the water, later phases at the nest-site. Homologies are traced with other cormorant species. In contrast to other members of the family, allopreening apparently does not occur. Both sexes incubate and care for the young. Observations on families of different ages over the 12-day period allowed the development of the young to be traced up to the age of about 40 days. Egg-laying takes place in most months of the year, with a peak in April-June and perhaps a second peak about October. Observations on birds colour-ringed on an earlier visit suggested that individuals do not breed more than once in the year. Nesting success appeared to be very low in 1963.  相似文献   

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B. E. Marshall  J. Cooper 《Ostrich》2013,84(4):141-149
Ward, D. 1989. Behaviour associated with breeding of Crowned, Blackwinged and Lesser Blackwinged Plovers. Ostrich 60: 141–150.

The behaviour of Crowned Plovers Vanellus coronatus, Blackwinged Plovers V. melanopterus and Lesser Blackwinged Plovers V. lugubris in mate and territory acquisition and defence was documented and related to the habitats these birds occupy. The open habitat occupied by vanelline plovers makes them particularly vulnerable to predation and as a result, they have a highly-developed ability to detect potential predators and have developed a number of behavioural strategies to avoid predation. This has resulted in these birds having a higher reproductive success than that documented for other precocial birds.  相似文献   

7.
在豢养条件下,白鱀豚的游泳除背向上正常姿态外,尚有侧游、仰游、滚游、跳跃、直立、浮卧和滑行多种型式。呼吸间隔时间不均匀,最短5秒,最长243秒,呼吸率为109—143次/小时。它的昼夜活动表现出明显的“激烈活动”和“平缓活动”两种状态,后者可能是一种休息方式。  相似文献   

8.
SUMMARY

The distribution of four species of Chaoboras over selected parts of Zimbabwe is given. The effect of temperature on the duration of the larval life cycle is discussed in relation to the generation time and the lunar periodicity of the adult emergence period. There were apparently two generations of larvae present in the habitat at any one time, although these generations were not distinct due to the variations in the time taken by the larvae to complete development at any temperature. The emergence was synchronized to the lunar cycle, but the actual moon phase at which emergence occurred was variable, as the two populations under observation both changed from new moon emergences to full moon emergences during the study. Some observations on the behaviour of adult Chaoboras edulis are given.  相似文献   

9.
《Ibis》1953,95(4):581-614
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10.
V. E. M. Burke  L. H. Brown 《Ibis》1970,112(4):499-512
This paper summarises observations on the breeding behaviour of the Pink-backed Pelican Pelecanus rufescens at Rakewa, Nyanza Province, Kenya, where the species has bred for at least 200 years. Observations covered most of one breeding season, November 1962 to April 1963. Of at least 250 nests, 35 were closely observed. The community consisted of about 815 pelicans of which about 540 were adults. The death rate is estimated at 13% per annum and the mean life-span at about seven and a half years. The breeding site, in trees above a small swamp, is 15 miles from the favoured feeding ground. The colony is protected by local Luo people. The pelicans feed and roost mainly at the Miriu Delta, 15 miles away, travelling between the two places so high up as to be unseen. They fish in the early morning, visiting the colony to feed young mainly between 09.00 and 13.00 hrs. Once the young are large both parents roost away from the colony at the Delta. The breeding season takes place from August, towards the end of the rains, to March, at the end of the dry season. The birds breed in synchronised groups, the breeding cycle for any group occupying five months. Nuptial display is performed on the nest trees, by single pairs or small groups. Two main displays are described, “pointing” and “bill-clapping”. Mating occurs on the nest, with little preliminary display. Nests are slight stick structures, repaired from year to year, and used by other pelicans if abandoned. The clutch is normally two eggs, occasionally three. Both sexes incubate, with infrequent change-overs, for 33–35 days. The chick is first brick-red, becoming covered with white down. Feathers break through at about 12 days and have covered much of the body by 30 days. At 40 days chicks can recognise their own parent. They fly at 70–75 days. Parents feed chicks by regurgitation, sometimes into the nest. They brood them closely at first, but after 10–12 days leave them much alone. Large chicks thrust the head far into the parental gullet, and injuries result from such feeding struggles. Feeding usually occurs before mid-day, each parent normally delivering two feeds with a rest between. Curious convulsive movements of the young are probably begging displays. Forty-two young hatched in 35 nests, an average of 0.6 chicks/egg laid. The heaviest mortality among young occurred between 10–30 days when 31% of all chicks died. Young which flew were produced at the rate of 0.47/egg hatched, 0.28/egg laid, and 0.57/pair.  相似文献   

11.
SUMMARY

Breeding behaviour of Labeo umbratus was observed in the Modder River, Orange Free State, and ova were collected from below the site and hatched. Fry were reared for 12 months to confirm the identification of the ova collected. The behaviour of spawning fish and the oviposition site are described.  相似文献   

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K. R. L. Hall 《Ostrich》2013,84(3):113-125
Jackson, S. 1984. Predation by Pied Kingfishers and Whitebreasted Cormorants on fish in the Kosi estuary system. Ostrich 55:113-132.

Identification of otoliths from the regurgitated pellets of Pied Kingfishers Ceryle rudis and Whitebreasted Cormorants Phalacrocorax carbo from the Kosi estuary system provides information on the relative proportions of fish species in the diets of the birds. This information can be related to the feeding habits, distribution and abundance of their prey. It is also an indication of the feeding range of the birds. There is little overlap between both the size classes and the species of fish taken by the two predators. This is because of the difference in size and fishing techniques of C. rudis and P. carbo, and of differences in their feeding ranges. Competition for food between the two populations of birds studied is minimized by these differences.  相似文献   

14.
H. H. Hamling 《Ostrich》2013,84(1):9-16
Maclean, G. L. 1974. The breeding biology of the Rufouseared Warbler and its bearing on the genus Prinia. Ostrich 45: 9–14.

The Rufouseared Warbler Prinia pectoralis, a common species of the Kalahari scrub, nests after rain at any time of the year. Nest construction and nest sites are described. The clutch is normally three or four eggs. Incubation takes 12 to 13 days and the nestling period is 11 to 13 days. Data suggest that the Rufouseared Warbler is not a member of the genus Priniu, the generic position it currently occupies.  相似文献   

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16.
M. P. Kahl 《Ibis》1967,109(1):25-32
Hamerkops were studied in Uganda, mainly in the vicinity of Kampala, during January-August 1964. Behavioural observations were made of nest-building pairs, as well as of non-breeding birds.
Locomotion and feeding behaviour are described. Diving take-offs and landings, essential for entering or leaving a completed nest, are sometimes seen in other situations as well. Birds sometimes forage while on the wing, in addition to the more usual method while wading.
The most frequently seen comfort movements and maintenance activities are described. Hamerkops do not excrete onto their legs when over-heated as do the storks. The resting posture of sitting completely down on horizontal branches, which is common among Hamerkops, apparently is not known in any of the herons or storks.
Primarily hostile (Upright and Forward Threat) and primarily sexual ("Yip-purr", Nodding and False Mounting) social displays are described. During False Mounting, birds mount their partners repeatedly without making any attempt at copulation; reverse mountings, in which the other partner assumes the top position, are frequent.
The large, hollow nest and its construction are briefly described. During the 6–7 week building period at one nest, at least 8000 loads of material were added to the structure. Both members have an equal role in nest-building, and generally work independently of each other. They showed no stick-exchange displays as do herons and storks.
When all known aspects of the Hamerkop's behaviour are considered, there appears to be little similarity with either the herons or the storks. In fact, present behavioural evidence does not seem to indicate a particularly close relationship with any other birds so far studied.  相似文献   

17.
P. J. Mundy  A. W. Cook 《Ostrich》2013,84(3-4):72-84
Mundy. P. J. & Cook, A. W. 1977. Observations on the breeding of the Pied Crow and Great Spotted Cuckoo in northern Nigeria. Ostrich 48:72-84.

The breeding cycle of the Pied Crow Corvus albus was studied in 1971. The birds bred in the wet season and all of 23 pairs were single-brooded. They appeared to nest territorially, and mostly close to human habitations. Average clutch size was 4.8 eggs and the greenish eggs were either pale and lightly marked, or darker and heavily marked. The average incubation and fledging periods were 181/2 and 38 days respectively. Chicks hatched asynchronously. Five crow nests were found parasitised by the Great Spotted Cuckoo Clamator glandarius and it appeared that only one hen cuckoo was responsible. The cuckoo apparently did not remove, or even crack, host eggs. One instance of an adult cuckoo feeding a juvenile was seen. In terms of growth increments a cuckoo chick substituted for one-half a crow chick but developed faster and fledged in nearly one-half the time. The cuckoo reduced host breeding success practically to zero apparently by indirect means, which contrasts with its situation in Europe.  相似文献   

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R. J. Nuttall 《Ostrich》2013,84(2-3):110-117
Summary

Nuttall, R.J. 1992. Breeding biology and behaviour of the Quail Finch Ortygospiza atricollis. Ostrich 63:110-117.

During a study of the breeding biology of the Quail Finch Ortygospiza atricollis, observations of nest-building, egg-laying, incubation and nestling periods, and nestling development in a grassland near Pietermaritzburg, South Africa were supplemented with observations of breeding behaviour in captivity. Mean clutch size was 4,5 and eggs were laid at intervals of approximately one day. Incubation began after the third or fourth egg was laid. An incubation period of 15–16 days and an estimated nestling period of 18–19 days was recorded. Incubation and brooding are shared by both sexes. Breeding success was low (26,7% ?28,6%), with most losses resulting from predation during either the egg-laying or incubation stages.  相似文献   

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