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Two Umbrina species, U. canariensis Valenciennes 1843 and U. robinsoni Gilchrist and Thompson 1908, are recognised from southern Africa. The latter species was hitherto believed to be a synonym of Umbrina ronchus Valenciennes 1843 (type locality Canary Islands). U. canariensis is distributed along the South Africa eastern seaboard from Cape Point to Sodwana Bay and U. robinsoni is known from False Bay to Madagascar and Oman. African Umbrina taxonomy has, however, been hindered by geographic samples that were either too few or consisted of specimens of disparate length; and as a result the identification and distribution of South African Umbrina species was confused. Morphological comparison of a large number of South African Umbrina with specimens from the type locality (Canary Islands) confirmed the identity of South African U. canariensis and allowed for an expanded description of the species. However, differences between specimens of U. ronchus and those of the second South African species (n = 251) led us to resurrect U. robinsoni (Gilchrist and Thompson 1908) as a valid name for this species. U. robinsoni differs from U. ronchus in having a smaller supraoccipital crest and thus a less steep pre-dorsal profile; a shallower preorbital bone (13-21% head length [HL] vs 21% HL); and a shorter nostril-orbit distance (2.4-6.9% HL vs 7.8-8.5% HL). Colour patterns also differ between the two species, with U. ronchus lacking the oblique, wavy, white stripes evident on the flanks of U. robinsoni. U. ronchus does not occur in South African waters, and is an eastern Atlantic species occurring from Gibraltar to Angola. Specimens from the east coast of Africa (Mocambique to Gulf of Oman) that were previously identified as U. ronchus are U. robinsoni. Differences between U. robinsoni and U. canariensis include: a lower modal number of soft dorsal fin rays, (22-27 vs 24-30); less deep body depth, (26-36% standard length [SL] vs 33-39% SL); shorter pectoral fin length (15-21% SL vs 20-25% SL); longer caudal peduncle length (26-34% SL vs 21-28% SL) and snout length (27-38% HL vs 23-32% HL); and smaller orbit diameter (14-33% HL vs 23-34% HL). Otoliths of U. robinsoni differ from those of U. canariensis in being smaller, less elongate, lacking a massive post-central umbo and having a post-dorsal spine remnant. The body colour and nature of the striping pattern on the flanks differs markedly between the species: in U. robinsoni the oblique stripes are thin, wavy, white lines; in U. canariensis the oblique stripes are thicker, nearly straight and brown; U. robinsoni also lacks the triangle-shaped mark on the outer operculum and the dark pigmentation of the inner operculum that is found on U. canariensis. Spatial analysis of South African specimens collected with a variety of gear revealed U. robinsoni to be a shallow-water species found from the surf-zone to 40m, whereas U. canariensis occurs predominantly from 40 to 100m depth. Although both species occur throughout the South African eastern seaboard, U. canariensis is most common west of the Kei River, where the shelf is wider. Examination of three specimens of U. steindachneri Cadenat 1950 confirmed the presence of a fourth sub-Saharan Umbrina species that is limited to tropical West African waters from Senegal to Angola. U. steindachneri differs from the other African Umbrina in having a high number of soft dorsal rays (28-29), a greater 3rd dorsal spine length (25-27% SL) and a very pronounced and convoluted striping pattern on the flanks.

Interview questionnaires and access point surveys were conducted in order to describe and quantify the catch composition of the inshore net-fisheries in the Western Cape, South Africa. A total of 138 562 fish, representing 29 species from 20 families, was recorded in 141 monitored commercial gillnet fishing operations between February 1998 and October 1999. Numerically, the legal target species, harders Liza richardsonii,dominated the catches, contributing 94.87% of the total gillnet catch. Elf, Pomatomus saltatrix, horse mackerel Trachurustrachurus capensis, gurnard Chelidonichthys capensisand barbel Galeichthys felicepswere the most common bycatch species, and contributed 4.2% to the total catch numerically and occurred in 12–47% of the marine 44–64-mm gillnet catches that were monitored. Five species most frequently targeted by shore-anglers on the West Coast: galjoen Dichistius capensis, white stumpnose Rhabdosargus globiceps, hottentot Pachymetopon blochii, silver kob Argyrosomus inodorusand white steenbras Lithognathus lithognathus, also occurred in gillnet catches. Most of the bycatch consisting of immature, undersized fish that were often injured during entanglement and were not released alive. L. richardsoniialso numerically dominated the beach-seine hauls that were monitored (>99%) with only four bycatch species being recorded in low numbers. Beach-seine questionnaire respondents, however, reported sporadic catches of at least 17 bycatch species, including occasional appreciable catches of the important linefish species L. lithognathusand A. inodorus.

Total catch and effort for the inshore net-fisheries in the Western Cape, South Africa, were estimated by means of face-to-face questionnaire, telephone and access point surveys, analysis of factory records and compulsory catch returns. In most areas, gillnet fishing effort was confined to summer, with highest average catch per unit effort during months of low effort. Records of monofilament gillnet sales show that approximately 180 illegal nets are sold annually (20% of all sales). During the period 1994–1999, only 26 illegal mesh size nets were confiscated annually (14% of those sold) on average, indicating that few illegal fishers are apprehended. Beach-seine fishers appeared to operate opportunistically throughout the year along the West Coast, whereas South-West Coast permit-holders concentrate their activity during summer. Sources of survey error in effort and catch-rate estimation are discussed. Approximately 25 000 gillnet days and 3 200 beach-seine hauls made annually land around 6 000 tons of fish, substantially more than the mean annual reported catch of 1 369 tons. Comparison of observed or documented catches with compulsory catch returns confirmed that as little as 21% of the actual effort and only 8%of the fish caught are reported. Despite the fact that catches are much greater than those reported, the lowercatch rates, smaller average size of fish caught and historical and anecdotal evidence suggest that the harder Liza richardsoniistock is regionally over exploited in areas with high fishing effort. It is concluded that the inshore net fishery in the Western Cape is oversubscribed in most regions and a reduction in latent and "recreational" effort is therefore recommended. A suitable reduction in total effort may allow the L. richardsoniistock to recover, reduce the ecosystem effects of the fishery by reducing the amount of bycatch and improve catch rates for bona fidecommercial fishers. It would also facilitate improved monitoring and policing of the fishery and hopefully improve compliance with regulations.

Data collected by questionnaire and telephone surveys conducted during 1998 and 1999 are used to describe the socio-economic characteristics of inshore netfishers in the Western Cape. Approximately two-thirds of netfishers work or have worked in other fishing sectors and a further 6–50%, depending on the area surveyed, are retired. Very few (0–11%) permit-holders in most areas classified their occupations as netfishers and the majority claimed to make <5% of their income from netfishing. Estimated costs and returns to net permit-holders suggest that, in most areas, commercial netfishing at current levels of catch and effort is not economically sustainable in the long-term. Only Saldanha-Langebaan gillnetters and beach-seine permit-holders, on average, manage to cover their opportunity costs and make an economic profit. The lack of profits in other areas is compelling evidence that the net fisheries are at or beyond the open access equilibrium point, suggesting that effort reduction in the order of 60% is necessary if maximum economic yield is to be obtained from the fishery. The netfisheries provide part-time employment for approximately 2 000 crew in the Western Cape. Additional economic benefits and employment directly related to the fishery in the form of equipment and fuel purchases made by fishers, maintenance of fishing gear and the sale of fish are estimated to contribute at least R15 million to the regional economy annually. Between 42 and 76% of respondents felt that their catches had declined since they had started netfishing and most felt that no new permits should be issued. Knowledge of catch restrictions among respondents was low (53–73%), indicative of a lack of communication between management and fishers, poorly defined permit conditions and a lack of enforcement. Many fishers interviewed feel it is unfair that they are restricted to catching only low-value target species and do not adhere to the catch restrictions, even if they do know them. The importance of the netfishery for participants varies greatly between and within areas. In order to reduce effort equitably, current and potential new permit-holders should be assessed on an individual merit basis.

Abstract: Particles (approximately 180 to 250 Μm across) were reduced by CO-CO2, by H2-H2O, and by CO-CO2-H2-H2O in a small fluidized bed, with facilities for automatic sampling of off-gas. Structural changes in the preheating period and during reduction were followed by surface area measurements and by microscopy. During reduction, surface areas increased initially and then decreased, as porosity created by chemical reaction was reduced by sintering; ‘uniform internal reduction’ was observed from magnetite to wustite. Although the bed was operated under vigorously bubbling conditions, with flow rates 7 to 15 times the minimum fluidization velocity at temperature, gas utilization was high for abstraction of about two-thirds of the maximum amount of oxygen removable by the inlet gas. The utilization fell sufficiently in the remaining stages of the reaction for approximate rate constants to be estimated. The rate increased (a) with increasing temperature, (b) with increasing gas flow, (c) with increasing reducing potential of the inlet gas, and (d) with increasing hydrogen content of inlet gas. The off-gas analyses showed the importance of the water gas shift reaction within the pores of the fluidized particles.

To investigate ethnic differences and the effect of age and education on awareness and attitudes of women towards hormone replacement therapy (HRT), we conducted a questionnaire survey of 180 women attending a gynaecology clinic, of whom 152 (84.4%) responded. Seventy‐one of the women had heard of HRT. Awareness of HRT was higher in the 50‐59 year age group and in women with higher education, but lower in Indo‐Asian women than in white and black/Afro‐Caribbean women. Friends, relatives and the media were important sources of information (apart from the doctor), especially among the younger age groups. The women themselves ranked their overall understanding of HRT as ‘low’; 78% felt they did not know enough about the subject. A distorted perception of benefits/risks associated with HRT was also noted – cardiovascular protection was not appreciated, whereas there was an excessive fear of breast cancer. Twenty‐eight per cent of the menopausal, postmenopausal and hysterectomised women surveyed were current HRT users. We conclude that factors such as ethnicity, age and educational level have an impact on women's awareness of and attitudes towards HRT. Some confusion about the real benefits/risks still exists, which probably accounts for low acceptance of this treatment, and suggests that clinicians prescribing HRT need to be aware of these problems.