Showing papers in "Ostrich in 1974"
TL;DR: Totals in this study averaged 8 m2 of reeds, where nests are built and potential mates are courted, and relations with other species on the territory are described.
Abstract: Summary Craig, A. J. F. K. 1974. Reproductive behaviour of the male Red Bishop Bird. Ostrich 45:149-160. Male Red Bishop Birds Euplectes orix show territorial behaviour while in nuptial plumage. Territory-holders drive off other conspecifics in Chases or by means of Threats. Bouts of threatening between neighbouring males are common; FightsMayoccur. Relations with other species on the territory are described. Territories in this study averaged 8 m2 of reeds, where nests are built and potential mates are courted. No feeding is done on the territory. Three calls termed Chipping, Rattling and Sizzling form a large part of the male's activity. Chipping is the alarm call, while Rattling and SizzlingMaybe important in mate attraction. In courtship the male makes a characteristic flying approach, a Bumble-flight, followed by the perched Swivelling display. The copulation approach is similar in form. Any bird in non-breeding plumageMaybe courted, since no response from the partner seems to be necessary.
25 citations
TL;DR: It is not surprising that egg-covering is most highly evolved in tropical and subtropical regions where predator-pressure is higher, and the danger of overheating by direct sun is greater, than elsewhere.
Abstract: Summary Maclean, G. L. 1974. Egg-covering in the Charadrii. Ostrich 45: 167–174. Deliberate egg-covering in the Charadrii (waders) occurs in at least 13 species in four families (Jacanidae, Glareolidae, Charadriidae and Thinocoridae). The habit is most widely developed in the genus Gharadrius, of which at least four species cover their eggs. Egg-covering is done by kicking material over the eggs with the feet in most species, but in the Glareolidae and probably some other groups, only the bill is used. The primary function of egg-covering appears to be concealment, but the secondary function of thermoregulation appears to have become almost as important in a few species, especially as a device to insulate the eggs against exposure to the sun. It is not surprising that egg-covering is most highly evolved in tropical and subtropical regions where predator-pressureMaybe higher, and the danger of overheating by direct sun is greater, than elsewhere.
20 citations
TL;DR: The distribution of seabirds off the southwestern coast of Africa was observed during April and November, and observed south of Africa in March, April and May, the least in November as discussed by the authors.
Abstract: Summary Summerhayes, C. P., Hofmeyr. P. K. & Rioux, R. H. 1974. Seabirds off the southwestern coast of Africa. Ostrich 45: 83–109. The distribution of seabirds off the southwestern coast of Africa was observed during April. May and November, and observed south of Africa in March. Most seabirds off the west coast were concentrated near to the coast or over the edge of the continental shelf. These are sites where forms of upwelling bring water rich in nutrients to the surface of the sea. The most birds were seen in March, April and May, the least in November. Most common over the shelf-edge were, in order of abundance, Blackbrowed Albatross, Cape Hens, Shy Albatross, Yellownosed Albatross, Wilson's Storm Petrels, Cape Gannets, Common/Arctic Terns, and Antarctic Skuas. Seasonal shifts in their ranges and population densities probably reflect the influence of breeding and migration. Comparable concentrations of seabirds were only seen as the cold, nutrient-rich waters of the Subantarctic were approached south...
20 citations
TL;DR: It seems probable that recruitment to the breeding population at these colonies is insufficient to balance adult mortality and the population may be declining, and some conclusions can be deduced from the results.
Abstract: Summary Houston, D. C. 1974. Mortality of the Cape Vulture. Ostrich 45: 57–62. An attempt was made to analyse the ringing returns of the Cape Vulture Gyps coprotheres from Transvaal colonies. Although it is not yet possible to determine annual mortality rates, some conclusions can be deduced from the results. Mortality during the early age classes is high and is over 500; during the first year. Mortality must decline rapidly with age, but it seems probable that recruitment to the breeding population at these colonies is insufficient to balance adult mortality and the population may be declining.
17 citations
TL;DR: The East African status of the 24 Lari recorded is summarized and clarifies, especially the breeding of eight terns, two gulls and the African Skimmer, and breeding seasons are discussed fully.
Abstract: Summary Pritton, P. L. & Erown, L. H. 1974. The status and breeding behaviour of East African Lari. Ostrich 45: 63–82. This paper summarises and clarifies the East African status of the 24 Lari recorded, especially the breeding of eight terns, two gulls and the African Skimmer. Breeding seasons are discussed fully. The season for terns and the Sooty Gull on offshore coral islets in northern Kenya, mainly in July-August when the islands are least accessible, is probably a man-orientated defence mechanism rather than a response to food availability. Inland, the Greyheaded Gull breeds in comparatively inaccessible sites, on islands in large lakes, generally during the main rains. Here it is believed more likely that food supplies are influenced by the onset of rains, and that the inaccessibility of sites at that season is a secondary advantage. Whiskered Tern breeding is mainly initiated by the onset of rains and the consequent creation of suitable habitat. It is uncertain what factors influence Skimmers to ...
16 citations
TL;DR: New data from comparisons of the egg and red blood cell proteins, using the technique of isoelectric focusing in acrylamide gel, indicate that Promerops is a specialized starling and that an appropriate taxonomic treatment is to include the subfamily Promeropinae in the Sturnidae.
Abstract: Summary Sibley, C. G. & Ahlquist, J. E. 1974. The relationships of the African sugarbirds (Promerops). Ostrich 45: 22–30. Certain characters of the sugarbirds (Promerops) seem to suggest that the genus may be a geographically isolated derivative of the Australo-Papuan Meliphagidae or a separate group of unknown ancestry, the Promeropidae. Both theories have received support to the present day. New data from comparisons of the egg whi te and red blood cell proteins, using the technique of isoelectric focusing in acrylamide gel, indicate that Promerops is a specialized starling and that an appropriate taxonomic treatment is to include the subfamily Promeropinae in the Sturnidae. This discovery not only explains the characters of Promerops but solves one of the most contentious zoogeographic problems in ornithology.
11 citations
TL;DR: Adult moult records support the sequence and duration of moult suggested by Douthwaite (1971) though no overall decrease of moul activity was recorded during the breedi...
Abstract: Summary Sugg, M St J 1974 Mensural and moult data from a breeding colony of Pied Kingfishers Ostrich 45: 227–234 Pied Kingfishers were ringed over two breeding seasons at a breeding colony on the Kenyan shore of Lake Victoria Data were collected on weight, wing and bill length, injury and moult Bill abrasion and breakage from nest excavation was found in both sexes and regeneration of worn and broken bills was recorded Adult birds of both sexes returned to the colony to breed but no juvenile was recaptured the year after hatching Females are slightly larger than males (wing length) and both sexes showed a weight increase in the evening prior to roosting Juveniles had shorter wings and bills than adults but their weights were similar Their bills were short, soft, weak and the gape was salmon pink No juveniles showed any moult Adult moult records support the sequence and duration of moult suggested by Douthwaite (1971) though no overall decrease of moult activity was recorded during the breedi
10 citations
TL;DR: Nesting habitat at Lake McIlwaine, Rhodesia, Ardea purpurea nests in bulrush Typha latifolia stands or on island termite mounds covered with reeds Phragmites mauritianus, which are connected to the mainland by Polygonum senegalense weed.
Abstract: Summary Tomlinson, D. N. S. 1974. Studies of the Purple Heron, Part 1: Heronry structure, nesting habits and reproductive success. Ostrich 45: 175–181. At Lake McIlwaine, Rhodesia, Ardea purpurea nests in bulrush Typha latifolia stands or on island termite mounds covered with reeds Phragmites mauritianus, which are connected to the mainland by Polygonum senegalense weed. Nest construction was different in thickness, diameter, height and materials used between the two types of nesting habitat. Clumping of nests in pairs and trios was apparent andMayhave some social significance. The Marsh Harrier Circus ranivorus preyed on the eggs and small chicks of the heron, whilst the Clawless Otter Aonyx capensis probably preyed on large chicks destroying the nest completely in the process. Low lake levels appear to be a major limiting factor to nesting success.
9 citations
TL;DR: Skead et al. as discussed by the authors described the topography, climate and habitats of the S.A. Lombard Nature Reserve and the status of 183 species recorded while the author was resident on the reserve, July 1964 to June 1967, arranged into the various habitat types.
Abstract: Summary Skead, D. M. 1974. Habitats and feeding preferences of birds on the S.A. Lombard Nature Reserve, Transvaal. Ostrich 45:15-21. The topography, climate and habitats of the S.A. Lombard Nature Reserve are described. The status of the 183 species recorded while the author was resident on the reserve, July 1964 to June 1967, was arranged into the various habitat types. It was found that 25% were residents while 65% of the residents occurred in the “Indifferent” category. Birds with a mixed diet predominated, 48,9%, while insect-eaters rated second, 35,8%.
8 citations
TL;DR: The throat puffing component in the Aggressive Upright Display appears unique to A. purpurea as does the clappering and sudden retraction of the neck in the Stretch Display.
Abstract: Summary Tomlinson, D. N. S. 1974. Studies of the Purple Heron, Part 2: Behaviour patterns. Ostrich 45: 209–223. Some aspects of Purple Heron Ardea purpurea behaviour have been covered although the study is not complete. Further observations are needed, especially on pair formation, nest building and copulation. Many of the displays described for the Ardeidae are clearly homologous and only slight differences exist. The throat puffing component in the Aggressive Upright Display appears unique to A. purpurea as does the clappering and sudden retraction of the neck in the Stretch Display. Birds raised in captivity provided valuable information on agonistic behaviour patterns and the behaviour of young.
TL;DR: In the Western Cape Province there has been little change in the status of either species but there are indications that D. viduata is appearing mote regularly in the Eastern Cape Province and the position in East Griqualand and the Transkei is obscure.
Abstract: Summary Clark, A. 1974. The status of the whistling ducks in South Africa. Ostrich 45:1-4. Since the 1920's the status of Dendrocygna viduata and D. bicolor has changed from that of an irregular to that of a regular species in the Transvaal, Zululand, Natal and Orange Free State. In more recent years their numbers have shown a steady increase and breeding has been established. D. viduata numbers built up more quickly than D. bicolor and it has become an established resident whereas D. bicolor is primarily a summer visitor. In the Western Cape Province there has been little change in the status of either species but there are indications that D. viduata is appearing mote regularly in the Eastern Cape Province. The position in East Griqualand and the Transkei is obscure. In South West Africa, excluding the north east corner, D. viduata remains irregular and D. bicolor rare. The preference shown by both species for areas where sewage effluent is disposed of and for new storage dams inevitably links their spr...
TL;DR: The South African National Unit for Bird-Ringing Administration now produces comprehensive computer print-outs of ringing and recovery information and as a result this published report is highly condensed.
Abstract: Summary Elliott, C. C. H. 1974. Sixteenth ringing report for Southern Africa. Ostrich 45:161-166. A report of ringing activities in Southern Africa from 1 July 1970 to 30 June 1973 is presented. The newly founded South African National Unit for Bird-Ringing Administration now produces comprehensive computer print-outs of ringing and recovery information and as a result this published report is highly condensed. Details of the totals of palaearctic migrants ringed and recovered are given together with those from the major studies, past and present, on ethiopian species.
TL;DR: Schulten et al. as mentioned in this paper analyzed the Gullet and stomach contents of 23 Southern Pochards, 17 Fulvous Treeducks, 14 White-faced Treeduck, 15 Hottentot Teals, 4 Redbilled Dacks, 1 Whitebacked Dack and 1 Pigmy Goose.
Abstract: Summary Schulten, G. G. M. 1974. The food of some duck species occurring at Lake Chilwa, Malawi. Ostrich 45: 224–226. Gullet and stomach contents of 23 Southern Pochards, 17 Fulvous Treeducks, 14 White-faced Treeducks, 15 Hottentot Teals, 4 Redbilled Teals, 1 Whitebacked Dack and 1 Pigmy Goose were analysed. These birds were shot in the Lake Chilwa area (Malawi, C. Africa) between 1969–1972. Most of the food components were identified and their occurrence is presented in a table. The results are discussed.
TL;DR: Data suggest that the Rufouseared Warbler is not a member of the genus Priniu, the generic position it currently occupies.
Abstract: Summary 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.
TL;DR: From August 1967 to November 1970 roadside counts of Blackshouldered Kites Elanus caeruleus were made along the Great North Road from the Pienaar's River Irrigation Settlement, near Hammanskraal, to Warmbaths, Transvaal.
Abstract: Summary Skead, D. M. 1974. Roadside counts of Blackshouldered Kites in the central Transvaal. Ostrich 45: 5–8. From August 1967 to November 1970 roadside counts of Blackshouldered Kites Elanus caeruleus were made along the Great North Road from the Pienaar's River Irrigation Settlement, near Hammanskraal, to Warmbaths, Transvaal. The mean density for this period was 10 km per bird. Counts were also made along the same route, but for a shorter distance to the farm Vaalbosch. The mean density for this route was 17 km per bird. Relative density was higher than in the Cape Province.
TL;DR: Numbers made at various waters in the Transvaal and Orange Free State, South Africa, in which the numbers are separated according to plumage are presented and discussed in the light of the work done by Siegfried (1968, 1970).
Abstract: Summary Clark, A. 1974. Plumage changes in the male Maccoa Duck. Ostrich 45: 251–254. Maccoa Duck Oxyura mi ccoo counts made at various waters in the Transvaal and Orange Free State, South Africa, in which the numbers are separated according to plumage, are presented and discussed in the light of the work done by Siegfried (1968, 1970) on this species. Males invariably outnumber females and the indications are that Transvaal birds move out of the area during winter when most males are in non-breeding plumage. There is little difference in the pattern of plumage changes between Transvaal and Cape birds.
TL;DR: The list of species affected with botulism in an Orange Free State dam is given, and a few short notes on the problems encountered in assessing the number of affected birds, and the factors affecting mortality rates are given.
Abstract: Summary Van Heerden, J. 1974. Botulism in the Orange Free State goidfields. Ostrich 45: 182–184. The list of species affected with botulism in an Orange Free State dam is given together with a few short notes on the problems encountered in assessing the number of affected birds, and the factors affecting mortality rates.