In order to study the movements and activities at sea of jackass penguins rearing chicks, a radio telemetry study was undertaken. Twenty five transmitters were attached to breeding adult penguins at their nest sites. These penguins were tracked for a total of 414 hours using a system of antennae on a motor–boat, the island and land–based stations. The foraging paths, foraging duration, foraging distances and swimming speeds were studied. The penguins' foraging patterns were similar; they generally left the island at night and travelled towards their foraging area, actively foraging from first light until they swam back to the island. The foraging durations and distances varied, as did the swimming speeds, according to availability of food.

The production of acid mine drainage (AMD) containing high amounts of sulfate, heavy metals and low pH is of increasing concern. AMD is highly corrosive and results in economic and environmental problems. Organic electron donors for sulfate reduction were chemically characterised for potential use in AMD treatment. This was done in a process to develop a correlation between chemical composition and the capacity to drive sulfate reduction. Potential organic electron donors for sulfate reduction were chemically characterised in terms of dry matter content, ash content, total Kjeldahl nitrogen, lignin content, cellulose content, crude fat, crude fibre, in vitro digestibility, water-soluble carbohydrates, total non-structural carbohydrates and starch content. The chemical composition of the organic electron donors was then compared to results obtained from pilot plant studies where the organic electron donors for sulfate reduction were evaluated in terms of sulfate reduction. The chemical composition of the carbon source severely impacted its capacity to drive sulfate reduction and may be used to assist in predicting the sulfate reduction capacity of a carbon source. Organic electron donors for sulfate reduction high in protein content and low in lignin content or high in carbohydrate and crude fat content increased the capacity of a carbon source to drive sulfate reduction. The higher the fibre content of a carbon source, the lower the capacity to drive sulfate reduction. No correlation could be drawn between % dry matter, % ash content and sulfate reduction for the organic electron donors tested. Chemical characterisation can be used to assist in predicting sulfate reduction capacity of organic electron donors.

With 8 figures in the text) Jackass penguin chicks from the age of about 10 days were hand reared on different diets: mullet Liza richardroni, anchovy Engraulis capensis and squid Loligo reynaudi, until they fledged. The weight of food fed and the daily weight increment of the chicks was measured. Excreta were collected every 5-6 days and analysed to establish metabolized energy and metabolic efficiency. Culmen measurements were taken regularly and plotted against age. The age, weight and sum of food fed up to fledging was compared between diets as well as with field data. Compensatory growth was exhibited when stunted chicks on a relatively poor diet had their diet changed to a relatively better diet.

The formation of floating sulphur biofilm was observed in the microbial ecology studies of tannery ponds undertaken by the Environmental Biotechnology Group at Rhodes University. This was related to the steep Redox gradients established at the air/ water interface of anaerobic, organically loaded and actively sulphate reducing systems. This study investigated the potential for applying these observations in developing a floating sulphur biofilm reactor for the removal of sulphide from sulphide-rich effluents produced in wastewater treatment systems. This was carried out in five sequential experimental phases. Where original studies had been undertaken using sulphide-rich water derived from sewage sludge as the carbon source, the successful establishment of a floating sulphur biofilm from effluent of lignocellulose-derived wastewaters had been shown. The effect of influent sulphide concentrations, flow rate and reactor dimensions on the sulphur biofilm formation were investigated for the optimisation of elemental sulphur recovery and sulphide removal efficiency. Polysulphide formation was enhanced by inserting a silicone tube rack and resulted in increased elemental sulphur recovery. Sulphide removal efficiency of 65% and a sulphur recovery of 85% were obtained at the end of the investigation while inter-harvest recovery period of the biofilm was reduced from an initial 4-5 days to 6-12 hours.

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