DISTRIBUTION,MIGRATION AND TIMING OF MOULT IN THE SOUTH AFRICAN CLIFF SWALLOW

Earle, R. A. 1987. Distribution, migration and timing of moult in the South African Cliff Swallow. Ostrich 58:118-121. The South African Cliff Swallow Hirundo spilodera breeds in South Africa mainly between 25 and 31S and 24 and 31E. In some years with exceptionally high rainfall the breeding range is more extensive. Man has probably had a pronounced influence on the present-day distribution of this species. Seven winter recovery/collecting localities are known from the lower Congo basin in Zaire. Possible migrating birds were observed in Zambia and Malawi in the east, and on the Namibian coast in the west. The few sight records suggest a direct migrational route over Botswana. Moult takes place between March and September primarily in the winter quarters, but about 2% of the birds handled during March and April started moult before migrating.     

THE SYSTEMATIC POSITION OF THE SOUTH AFRICAN GANNET

Summary

Randall, R. M., Randall, B. M., Cooper, J. &; Frost, P. G. H. 1986: A new census method for penguins tested on Jackass Penguins Spheniscus demersus. Ostrich 57: 211–215

A census method for Jackass Penguins based on their moulting cycle is described. Population estimates were substantially higher with this method than with total counts, but were not dissimilar to maximum estimates obtained from strip counts. The moult method estimates the size of the entire population and is independent of the breeding cycle and breeding status of both individuals and population. It is not plagued by the problem of absenteeism encountered during most phases of the penguin annual cycle and is independent on their diel activity. The drawbacks to the method are that it is laborious and protracted, that it does not differentiate between the breeding population and the whole population, and is unsuited to some species and some habitats.     

NOTES ON THE SOUTH AFRICAN SPECIES OF CORVUS

Winterbottom, J. M. 1975. Notes on the South African spscies of Corvus. Ostrich 46:236-250. The three indigenous species of Corvus in South Africa are compared in respect of geographical and ecological distribution, status, breeding, food, economic importance and general habits. Apart from the limitation of range in albicollis by its nesting requirements, it is extremely difficult to pin-point any factors in which the species so differ as to explain the paradoxes of their distribution.     

ON THE SOUTH AFRICAN RACE OF THE LITTLE SPOTTED WOODPECKER

Discriminant analysis functions have previously been determined for sexing Mediterranean Yellow-legged Gulls Larus michahellis michahellis from the western Mediterranean basin. However, data from eastern Mediterranean populations are lacking. In this work, we used morphometric data from a sample of 81 Mediterranean Yellow-legged Gulls (39 males and 42 females) breeding in the Gulf of Gabès in south-eastern Tunisia to (1) determine a discriminant function useful for sex discrimination, and (2) assess the accuracy of previously published functions in sexing Mediterranean Yellow-legged Gulls from our study area. Our results showed marked sexual differences in all morphological measurements, with males being significantly larger than females. The best discriminant function included head length, bill depth and wing length, and accurately classified 93% of sampled birds. We also found that Mediterranean Yellow-legged Gulls from the Gulf of Gabès could accurately be sexed using discriminant functions determined for another North African population, but not with a function determined for a South European population, although distances between sites are almost the same.     

PRODUCTION OF THE AFRICAN CATFISH (CLARIAS GARIEPINUS) I. GROWTH,MORTALITY AND YIELD SOUTH OF THE ZAMBEZI

SUMMARY

Clarias gariepinus were sampled from eight water bodies in southern Africa between 1973 and 1975. Aging results indicate a similar growth pattern for most areas with a near linear age-length relationship. Between year growth compensation was found to be present in Lakes Kyle and Mcllwaine in Zimbabwe, and to a lesser extent in Hardap Dam, South West Africa, but not present in Lake Kariba, Zimbabwe.

The fishable biomass of catfish from Lake Kyle is estimated between 0,61 to 1,14 kg ha^?1. Fishable biomass for all species is in the range 12,1 to 22,7 kg ha^?1.

The instantaneous growth rate was found to be between 0,20 and 0,25 for fully recruited age groups. The fishing mortality appears to be in the range of 0,4 for Lakes Kyle and Kariba and 0,5 for Lake McIlwaine. All of these levels are above the yield per recruit F₀, 1 levels of 0,27, 0,28 and 0,24 respectively which would normally indicate that each of these stocks is being overexploited. However, this does not appear to be the case in these tropical impoundments.     

AGENCY, PERSONHOOD AND THE 'I' OF DISCOURSE IN THE PACIFIC AND BEYOND

Sahlins bases his account of Polynesian 'heroic history' partly on the fact that chiefs used the pronoun 'I' in reference to their whole group. Mosko (1992) argues that Sahlins's consequent emphasis on 'encompassment' as the modality of chiefly action is diametrically opposed to Strathern's on 'partibility', the effacement of parts of the person as a condition of action. Drawing on comparative material from the New Guinea Highlands, where big men also use 'I' for their whole group, and on Benveniste's and Urban's accounts of the meaning and use of personal pronouns, I argue instead that moments of both encompassment and partibility are inherent in language, corresponding to two distinct dimensions in which the pronouns are meaningful (the 'direct indexical' and the 'anaphoric'), and that close attention to the interaction between the two can yield new insights into the nature of personhood and social agency.     

NOTES ON THE TAXONOMY, SPAWN AND LARVAL DEVELOPMENT OF SOUTH AFRICAN SPECIES OF THE INTERTIDAL LIMPET SIPHONARIA (GASTROPODA: PULMONATA)

The taxonomy of South African Siphonaria is reviewed. We concludethat nine species are valid. These are: S. anneae Tomlin, 1944;S. capensis Quoy & Gaimard, 1833; S. compressa Allanson,1959; S. concinna Sowerby, 1824; S. dayi Allanson, 1959; S.nigerrima Smith, 1903; S. oculus Krauss, 1848; S. serrata (Fischer,1807) and S. tenuicostulata Smith, 1903. Of these, Siphonarianigerrima Smith, 1903, has been incorrectly synonymized withSiphonaria carbo Hanley, 1858, which is not present on SouthAfrican shores. S. aspera Krauss, 1848 is reduced to a juniorsynonym of S. Serrata (Fischer, 1807). Shell characteristicsand mode of larval development are described for these nineSouth African species. All species deposit benthic egg massesand development may be either planktonic with swimming veligerlarvae (S. capensis, S. concinna and S. oculus) or direct, withcrawling larvae emerging from the eggs (S. anneae, S. compressa,S. dayi, S. nigerrima, S. serrata and S. tenuicostulata). (Received 20 November 1992; accepted 24 January 1994)