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 DR EE CAMPBELL

Tel: 041-5042329

Fax: 041-5832317

E-mail: btaeec@upe.ac.za

THEME: SUSTAINABLE ENVIRONMENT THEME

PROGRAMME: SE: MARINE AND COASTAL RESOURCES

THRUST: COASTAL COMMUNITIES AND LIVING RESOURCES

TITLE: BIOLOGICAL MANAGEMENT AND UTILISATION OF SOLAR SALT WORKS

The biology of solar saltworks is integral to salt production and can have a positive or negative influence on the quality and quantity of salt produced. A balanced or efficient biological system produces optimum quantities of organic materials properly distributed between the planktonic and bottom communities. An inadequate biological system lacks sufficient biological productivity, while an unbalanced system is caused by sub-optimal distribution of organic materials (Davis 1978).

The future of some South African solar saltworks is uncertain due to unbalanced biological systems. Various factors promote a biological system that is unsatisfactory to salt production, including excessively deep ponds, high concentrations of combined nitrogen and phosphorous, and high organic production. Disturbances due to excessive nutrients allow species that are usually constrained by low nutrients and high salinities to reproduce excessively, outcompeting those species beneficial to salt production.

The aims of this project were the identification of problems associated with an unsatisfactory or unbalanced biological system and to provide biological management guidelines to assist local salt production companies to improve the quality and quantity of salt produced. To achieve this, the physical factors, nutrient regimes, organic concentrations, and biota within four salinas were investigated. A comparative analysis of the biota within the four salinas was also conducted. The aim was to identify differences in biomass between the planktonic and benthic communities, and, in the watercolumn, between macrophytes and phytoplankton. Particulate organic carbon (POC) in the benthos and water column was also analysed and all compartments were converted to similar units.

Two small, comparatively young solar saltworks near Velddrif provided examples of naturally oligotrophic (Velddrif salina) and balanced (Kliphoek salina) systems. The brine feeding the Velddrif salina is pumped from an ancient underground aquifer and fertilization was required to establish a suitable biological system. The Kliphoek salina is less than ten years old, surrounded by agricultural land and the brine is pumped from a dead-end of the Berg estuary, which forms the initial pond of the saltworks.

The brine for the two East Coast salinas is pumped from the Swartkops Estuary, close to the Chatty River. Brine enters the Swartkops salina, flowing gravimetrically to the second pond from which approximately half of the brine is pumped 1.5 km to the Missionvale salina. Both salinas are surrounded by high-density informal housing with no structured sewage or refuse removal. The Swartkops solar saltworks receives large volumes of nutrients derived from the informal settlements via intake water. Over the past five to eight years, there has been a marked increase in nutrient concentrations in the water pumped into the saltworks (MacKay 1994, Du Toit 1998). Nutrient concentrations showed large temporal variations, conducive to fluctuations in biomass of organisms favorable to salt production and the encouragement of species detrimental to salt production.

An important organism influenced by water quality is the brine shrimp Artemia salina. A. salina is integral to salt production. Brine shrimps clear the brine by grazing on phytoplankton, provide dissolved organic matter for the red halophylic bacteria, and their excretory wastes are expelled in a capsule, transferring significant quantities of organic matter to the sediments.

Artemia concentrations in the Kliphoek and Velddrif systems are satisfactory and do not exhibit large temporal fluctuations. The variable nutrient loads of the brine entering the Swartkops and Missionvale salinas result in large fluctuations in Artemia populations and insufficient cleaning of the brine entering the crystallizer ponds.

The depth of certain ponds in the Swartkops and Missionvale salinas are unacceptably deep with insufficient phytoplankton biomass in most of the Swartkops ponds. An experiment in which the depths of two evaporation ponds in the Swartkops system were lowered for two months demonstrated that shallower brine depths (decreased from 1.2 m to 60 cm) significantly increased phytoplankton concentrations in the respective ponds. The equivalent salinity ponds in the Missionvale system were the control and showed no significant increase in chlorophyll a concentrations (using water chlorophyll a as an indication of phytoplankton biomass).

Vascular plants and macroalgae dominated the biomass in the inlet ponds of the Swartkops, Missionvale and Kliphoek salinas while benthic microalgae dominated the first four ponds of the Velddrif system. Macroalgae predominated in the Swartkops salina until the mid-salinity ponds, contributing at least 50% of the biomass until the fifth pond, where benthic microalgae became dominant.

In the Missionvale salina, the large macroalgal biomass in the first pond was replaced in the third pond (at lower salinity than in the Swartkops system) by phytoplankton and a benthic-dominated system. Benthic microalgae had the highest biomass in the pre-crystallizer pond but was replaced by the phytoplankton component in the crystallizer, pond eight.

Benthic microalgal- dominated evaporation ponds are advantageous to the efficient functioning of a salina. Benthic microalgae are a primary carbon source for estuarine food webs, are an important component in nutrient cycles and function as sediment stabilisers (Pinckney and Zingmark 1983).

The macroalgae that dominated the first pond of the Kliphoek salina were replaced by phytoplankton that comprised at least 75% of the living biomass throughout the remainder of the system. Benthic microalgae increased proportionally to the phytoplankton component as the salinity increased but did not dominate as in the Missionvale and Velddrif systems. In contrast, as the brine progressed through the Velddrif salina, phytoplankton steadily replaced benthic microalgae as the dominant primary producer. Phytoplankton maintained the highest biomass in the crystallizers of all four of the salinas, with benthic microalgae also making up a significant portion.

The concentrations of water POC and benthic POC in relation to the biotic (living) components were also analysed. Macroalgae in the first and fourth ponds of the Swartkops salina, and the first pond of the Missionvale salina dominated the watercolumn carbon but for the remainder, benthic POC and water POC contained more than 95% of the carbon content. This has particular relevance to salinas where high POC concentrations can detrimentally affect salt production. Water column POC levels in the crystallizer ponds of the Missionvale system were highest of the four salinas. Next highest was Kliphoek, Swartkops and the lowest by a factor of 2 was Velddrif. The comparatively high POC levels in the Missionvale salina is most likely due to the late transition from a benthic-dominated system to phytoplankton-domination in the crystallizer pond.

The elevated phytoplankton biomass in the initial ponds of the Swartkops and Missionvale salinas was also greater than that recorded for the Swartkops estuary (Hilmer 1984) indicative of the increased planktonic primary production within the salinas. Maxima of benthic POC were found in mid-salinity ponds of both the Swartkops and Missionvale salinas.

The unacceptably high POC levels in the pre-crystallizer ponds of three of the systems are a symptom of their hypertrophic state. Management recommendations have been made to the systems' managers and these include: The transfer of the inlet pipe of the Swartkops salina to limit influx of nutrients (Swartkops and Missionvale salinas); adjust pumping to keep the desired salinity in each pond (Davis 1978, Swartkops, Missionvale and Kliphoek salinas); adjust pond depths to allow light to reach pond bottoms (Swartkops, Missionvale and Velddrif salinas); and to install internal banks to maximize pond areas and reduce "short-cuts" across the ponds (Swartkops salina).

Davis, J.S. 1978. Biological management of solar saltworks. In: Fifth International Symposium on Salt. Ohio Geological Society. Vol. 2. Cleveland, Ohio.

Du Toit, S.R. 1998. Artificial wetlands in the management of solar saltworks. M. Sc. thesis, Department of Botany, University of Port Elizabeth. pp 117.

MacKay, H. M. 1994. Management of water quality in an urban estuary. Ph D thesis. University of Port Elizabeth, Port Elizabeth, South Africa. pp 242.

Pinckney, J. and Zingmark, R.G. 1993. Biomass and production of benthic microalgal communities in estuarine habitats. Estuaries 4: 887-897.

DEPARTMENT OF ZOOLOGY

Tel: 021-8083233

Fax: 021-8082405

E-mail: mic@land.sun.ac.za

THEME: SUSTAINABLE ENVIRONMENT THEME

PROGRAMME: SE: MARINE AND COASTAL RESOURCES

THRUST: MARINE AND COASTAL BIODIVERSITY AND CONSERVATION

TITLE: Behavioural ecology of southern African seahorses and pipefish (syngnathids)

Although this project was technically terminated in 2000, it will continue under a new NRF grant to TJ Robinson, M I Cherry, BA Cook and CA Matthee for 2001-2002, as it has effectively run for only one year to date (Funds allocated in 1999 were returned as the project was not operational, and in 1998 both students involved withdrew registration at mid year, so little was achieved.

This project has made excellent progress during the course of 2000. Tagging of seahorses (a prerequisite for behavioural studies) was investigated and proved impractical, so it was decided to focus on genetics aspects of the project. So far over 100 seahorses have been sampled non-destructively (by means of fin-clipping) from the Knysa and Swartvlei populations, of which 18 have been sequenced for the D-loop gene. To date five haplotypes have been identified, three of which are unique to Knysna and three of which are shared by the Swartvlei population.

An attempt is being made to extract DNA from a formalin-preserved specimen from the Keurbooms Estuary, as we were unable to find any seahorses there ourselves.

I do not recommend review of this project until the end of 2002, when it should have been effectively completed.

Tel: (021) 424-3330

Fax: (021) 424-6716

E-mail: lcompagno@samuseum.ac.za

THEME: SUSTAINABLE ENVIRONMENT THEME

PROGRAMME: SE: MARINE AND COASTAL RESOURCES

THRUST: MARINE AND COASTAL BIODIVERSITY AND CONSERVATION

TITLE: BIOLOGY OF THE CLASS CHONDRICHTHYES (CARTILAGINOUS FISHES: SHARKS, RAYS AND CHIMAERAS).

Overview of Important Findings and Implications for Science, Engineering and Technology 1996 to 2000

1. FAO Catalogs of World Sharks, Batoids and Chimaeroids. Catalog research includes basic systematics and morphological background work for preparation of a revised FAO catalog of world sharks, a new multiauthored batoid catalog, and a chimaeroid catalog. The original 1984 catalog proved to have a very broad and unexpected application to a variety of scientific disciplines in biology as shown by reference to Science Citation Index. The breath and depth of coverage for the new catalog was expanded beyond the scope of the original catalog to address a broader range of users as well as problems with the previous version. This included: a. Development of the Chondtaxon and Systema Chondrichthyes databases to support the writer's systematic and other biological research on chondrichthyans in general and production of the FAO chondrichthyan catalogs in particular. Systema Chondrichthyes is a text database and framework for production of the catalogs and for organization of biological data. The batoid catalog section of this was distributed to coauthors J.D. McEachran, P. Last, B. Seret, M. de Carvalho, and D. Ebert. b. Reexamination of hexanchoid, squaloid, pristiophoroid, batoid, squatinoid, heterodontoid, orectoloboid and lamnoid morphology, including skeletal anatomy, which allowed a reassessment of the relationships of these groups and of cranial character systems which have been misinterpreted for the last two centuries (particularly the basal plate structure of squalomorphs and jaw suspension of elasmobranchs). A major question that had to be addressed was if the squaloid sharks (Order Squaliformes) were monophyletic or not. c. Development of a synthetic classification and cladogram of the living chondrichthyan orders, building on published cladistic research subsequent to the 1984 shark catalog and the writer's own research, as a framework for the catalogs. c. Participation in a field trip in January and February 1996 to Thailand, Singapore, and Malaysia (including Sabah, Borneo) under the auspices of the UK Darwin Initiative program and the USA Ocean Wildlife Campaign, to collect data of relevance to the catalogs as well as for other projects. d. Preparation and completion of the accounts of the Orders Hexanchiformes, Pristiophoriformes, Squatiniformes, Heterodontiformes, Lamniformes, Orectolobiformes and the squaloid families Echinorhinidae, Squalidae, Centrophoridae and Oxynotidae for the first and second books of the three-volume FAO shark catalog. The catalog format was changed by FAO during the course of the period from a single volume in two parts to a three book set, each with separate introductory material, bibliography, and appendices. e. Completion of the second book of the shark catalog (Orders Heterodontiformes, Lamniformes, and Orectolobiformes), which will be published in early 2001. The FAO catalogs will also be published in modified form as an ETI Linnaeus database on CD-ROM.

2. FAO regional species identification guides. Contributions by the writer are included in the following guides, which are major taxonomic reviews of marine fishes and other organisms:

a. K. E. Carpenter and V.H. Niem (eds, first three volumes published in 1998, 1999, and 2000). FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. LJVC produced the peer-reviewed species guide to non-batoid sharks, batoids, and chimaeroids, coauthored with V. Niem, P. Last, M. de Carvalho, and B. Seret; these were published in 1998 and 1999 (the latter issued in 2000). This research included revisionary work on numerous families of cartilaginous fishes in the area, including the Rhynchobatidae and Carcharhinidae.

b. K. E. Carpenter, ed: FAO species identification guide for fishery purposes. The living marine resources of the Western Central Atlantic. LJVC wrote the peer-reviewed species guide to non-batoid sharks, which is in press (2001). This is a greatly expanded version of the original FAO WCA species sheets for sharks published in 1978 and also prepared by the writer.

3. Rhynchobatus systematic revision. Continuing work on the batoid genus Rhynchobatus (Rhynchobatidae) or 'wedgefishes'. These are mostly very large (3 meters maximum, except for one dwarf species) inshore batoids which are important fisheries species wherever they occur, and which are affected by the oriental fin trade and have major conservation problems from overfishing. Work included further analysis of morphometrics, meristics and skeletal characters for the revision, collection of additional material including adults of the undescribed dwarf wedgefish R. sp. B from Singapore, and publication of preliminary findings on the genus for the Western Central Pacific in the FAO WCP species guide in 1999. The basic findings include the discovery that the wide-ranging Indo-West Pacific R. djiddensis is a species complex that includes, so far, four similar species that are readily separable on meristics, morphometrics, external morphology, coloration, and skeletal features: R. australiae Whitley, 1939 with a wide if spotty range from Mozambique to Australia and the Philippines; R. djiddensis (Forsskael, 1775) from the Western Indian Ocean; R. laevis (Bloch & Schneider, 1801) from the Northern and possibly the Western Indian Ocean, and the Western Pacific; and R. sp. A, from the Western Pacific. Two additional species that are readily separable from the R. djiddensis complex and from each other include R. luebberti, from Tropical West Africa; and R. sp. B from Singapore and Indonesia.

4. River shark systematics. Continuing work on the revision of the river shark genus Glyphis has resolved some of the problems as additional new material became available and extent of variation within one of the species (sp. B) was established. Some highlights include: a. Discovery of characters of external morphology, coloration, tooth counts, tooth morphology, and vertebral counts to distinguish the species of Glyphis, with five or six species identified so far. b. Discovery of the Kinabatangan Glyphis by the Darwin Sabah Project, which proved to be undescribed (G. sp. B) and the same as a specimen of Glyphis collected over a century ago from Borneo. c. Validation of G. siamensis from Myanmar as a species separable from G. gangeticus and other species. d. Discovery that a big-jawed and big-toothed species of Glyphis from New Guinea and northeastern Australia (G. sp. A) is most likely to be a synonym of the problematical G. glyphis. e. Discovery that a flatheaded Glyphis from New Guinea and northern Australia is undescribed (G. sp. C). Preliminary findings on the Western Pacific species of Glyphis were published in the FAO Western Central Pacific species identification guide, and a short paper was published on the conservation status of G. gangeticus.

5. Miscellaneous published work and ongoing research, primarily on systematics and natural history of cartilaginous fishes, including: A published paper on a new species of Paragaleus from the Arabian Sea and the Persian Gulf; publication of chapters on systematics, morphology and biodiversity for a technical book on elasmobranchs edited by Dr. W. Hamlettfurther work on the systematics and morphology of sawfishes (Pristidae), some of which is published in the FAO WCP identification guide for batoid and some of which is in the sawfish section of the FAO catalog of world batoids; a short paper on the conservation status of the bluegray carpetshark, Heteroscyllium, for Chondros, which apparently wasn't published due to the chief editor's (S. Cook) death but which was used in the published IUCN 2000 Red List assessment of this shark as well as the FAO shark catalog; work on a paper on an undescribed genus and species of pseudotriakid shark from the Western Indian Ocean; work on a paper revising the sleeper shark genus Somniosus with K. Yano and J. Stevens; a review in preparation of the general biology of the sand tiger shark (Odontaspis ferox); a published paper on the dusky shark in the Mediterranean Sea; a published paper on three new species of Asymbolus catsharks (Scyliorhinidae) from Australia with P. Last and J. D. Stevens; work on an undescribed species of Bythaelurus catshark from the Galapagos Islands with J. McCosker preliminary work on a field guide to world sharks; work on a revision of the sixgill stingray genus Hexatrygon with P. C. Heemstra; a paper on cormorant predation by Cape fur seals by M. Marks and colleagues; ongoing research on behavioral ecology, systematics, population structure, and age and growth of catsharks (Scyliorhinidae) in Cape waters, by three students, M. Marks, B. Human, and A. Dainty at the University of Cape Town.

6. Systematic, zoogeographic and biological research on the southern African chondrichthyan fauna. This includes new locality records and new species discovered in the area, and compilation and analysis of locality data from Marine and Coastal Management Africana cruises off the southwestern and southeastern coasts of South Africa. A research report was completed in 1999 on distribution of cartilaginous fishes off the southwestern and southeastern Cape for the World-Wide Fund for Nature and the University of Cape Town; considerable work was accomplished on a paper covering the distribution of cartilaginous fishes off the southeastern coast of South Africa collected by RV Africana; work on a revised version of the 1989 field guide to South African sharks which may be expanded to all of Africa; publication of a paper on the feeding ecology of catsharks off the west coast of southern Africa with D. Ebert and P. Cowley; publication of a paper on the biology of southern African Mustelus with M. Smale; publication of a multidisciplinary paper on the biology of the Izak catshark off South Africa; a published checklist of the cartilaginous fishes of the South China Sea; a contribution on chondrichthyian diversity in a paper edited by M.J. Gibbons on the taxonomic richness of South Africa's marine Fauna was published in 1999; and a paper reviewing the systematics and biodiversity of southern African chondrichthyes was published in 2000.

7. Conservation of cartilaginous fishes. Conservation work included participation in the UK Darwin Initiative project on elasmobranch diversity and conservation in Sabah, Borneo, Malaysia, with several publications in print, in press, or in preparation including a paper in print on biodiversity, conservation and management of Sabah elasmobranchs; a paper in progress on a description of a new species of river shark, genus Glyphis, from Borneo; a paper in press on freshwater and coastal elasmobranchs in the Indo-West Pacific; papers in press on biodiversity of cartilaginous fishes in the South China Sea and adjacent areas; and a paper on the need for adequate systematic collections of Indo-West Pacific cartilaginous fishes. LJVC participated in the journal Chondros, dedicated to rational conservation, management and exploitation of sharklike fishes, until the unexpected and untimely death of its senior editor, S. Cook, in 1996; likewise LJVC prepared sections for the Ocean Wildlife Campaign book being prepared by S. Cook, which was apparently abandoned by OWC after his death. Also, LJVC prepared 21 accounts and coauthored 17 more out of 97 accounts assessing elasmobranch species for the IUCN Red List as part of his work for the IUCN Shark Specialist Group, which was published in 2000; an additional assessment was coauthored by B. Human, one of the SRC graduate students. Several southern African endemic sharks and other species of elasmobranchs found in southern Africa are now on the 2000 Red Lists. Two other papers were published on IUCN matters including one on the use of IUCN criteria for assessing species of cartilaginous fishes, and another on the conservation status of freshwater elasmobranchs. LJVC contributed to drafting of the FAO Action Plan for sharks by participating in a workshop in Tokyo. LJVC also participated in the Marine and Coastal Management chondrichthyan working group, which addressed conservation and management issues on South African cartilaginous fishes including regulating white shark cage diving and development of a South African management plan for cartilaginous fishes following the FAO Action Plan. LJVC wrote reports to motivate protection of the whale and basking sharks off South Africa; supplied information to the International Humane Society and the U.S. National Marine Fisheries Service for CITES listing of the white shark; supplied information to the Maltese government as part of a motivation by the UK Shark Trust for protection of the white shark in Maltese waters (which passed); and supplied information and to the South African Ministry of Environmental Affairs and Tourism for CITES listing of the basking shark.

8. White shark research. This included M. Marks' observations of white shark injuries to Cape fur seals, Cape gannets and African penguins; Marks' systematic free-diving behavioral observations of white sharks; further revision of the white shark complex behavior manuscript including interactions of white sharks with prey or nonprey organisms and inanimate objects (including seal and penguin decoys); the formation of a research alliance between SFRI, University of Stellenbosch, and SAM for sonic telemetry of white sharks (with funds awarded from the International Foundation for Animal Welfare); and further work on the skeletal morphology of the white shark with M. Gottfried. Publications include papers on white sharks biting boats and other inanimate objects by M. Marks and colleagues; size and allometry of white sharks; the morphology and biology of the giant megatooth shark (Carcharodon megalodon with M. Gottfried and C. Bowman; white shark predation on turtles and ocean sunfish; a review of the conservation status of the white shark; and on new tropical records of white sharks in the Indian Ocean. Research at SRC over the past decade and particularly over the last five years shows the popular and scientific concept of the white shark as a simple solitary eating-machine is incorrect. This animal is social and has complex social and asocial behavior involving over eighty different behavioral elements that we know of. Certain modern hypotheses on white shark predatory behavior such as 'bite-and-spit' prey-handling and 'exsanguination' of prey, obligate seal predation by large white sharks, and obligate lipophagy are seriously flawed. White shark interactions with people, including so-called 'attacks', have to be reinterpreted in the context of the white shark's complex behavior, including transferral of social behaviors to human beings, including agonistic activities, investigative behavior, displacement, and even play. Predation by white sharks on human beings does occur but is fortunately very rare; mistaken identity of humans for prey species may occur but may be less common than suggested in the literature.

9. Whale shark research. This included a multi-authored paper on recent sightings and strandings of whale sharks off South Africa; and the first South African satellite track of a whale shark, in cooperation with the U.S. Shark Research Institute and using a radio tag relayed by the French ARGOS satellite system.

10. Dr. R. Alexander was awarded her Ph.D. from the Department of Zoology, University of Cape Town. for outstanding work on the morphology of the circulatory system of batoids and other elasmobranchs, including the discovery of endothermy in batoids and comparison of batoid and lamnoid endothermy; she has several papers published on the subject and a book based on her masters and doctoral dissertations in preparation.

11. SRC SET involvement: SRC has major Science, Education and Technology involvement with local and international media, including numerous interviews and participation in natural history video documentaries on cartilaginous fishes with local film-producers and international producers including the BBC Natural History Unit, Survival Anglia, National Geographic, and Discovery Network (see Annual Reports for details). Also two semipopular books were published in which LJVC had written substantial chapters, the 1998 Reader's Digest explores sharks, and the 1999 Weldon-Owen Sharks, a revised version of an earlier book published in 1987. LJVC also was a scientific consultant for an educational book by M. Levine on white sharks, published in 1997. A SRC website was established, and work is in progress for major expansion.

Alexander, R. L. 1996. Evidence of brain-warming in the mobulid rays, Mobula tarapacana and Manta birostris (Chondrichthyes; Elasmobranchii: Batoidea: Myliobatiformes). Zool. J. Linnean Soc. (London), 118: 151-164, fig. 1-5.

Alexander, R. L. 1998. Blood supply to the eyes and brain of lamniform sharks (Lamniformes). J. Zool. London (1998) 245: 363-369, fig. fig. 1-3.

Beckley, L. E., G. Cliff, M.J. Smale & L.J.V. Compagno. 1997. Recent strandings and sightings of whale sharks in South Africa. Environmental Biology of Fishes, 50, (3): 343-348, 1tab., 3 fig.

 Cliff, G., L.J.V. Compagno, M. Smale, R. P. van der Elst, & S. P. Wintner. First records of white sharks, Carcharodon carcharias from Mauritius, Zanzibar, Madagascar and Kenya. South African Journal of Science, 96, July 2000: 365-367, fig. 1.

Collier, R. M., M. A. Marks & R. W. Warner. 1996. White shark attacks on inanimate objects along the northwest coast of North America. In Great White Sharks. The biology of Carcharodon carcharias, ed. A. P. Klimley & D. Ainley. Academic Press, pp. 217-222.

Compagno, L.J.V. 1995, 2000. Checklist of Philippine Chondrichthyes. Shark Research Center, South African Museum, SRC Report 19951107, Revised 2000-02-22. Revised version presented to the WWF Philippine shark biodiversity project, February 23, 2000.

Compagno, L.J.V. 1996. Review: Sharks of Hawai'I. Their biology and cultural significance. By Leighton Taylor. Copeia 1996(1): 231-233.

Compagno, L.J.V. 1997. Threatened fishes of the world: Glyphis gangeticus (Müller & Henle, 1839)(Carcharhinidae). Environmental Biology of Fishes 49: 400, ill.

Compagno, L.J.V. 1998. Red List species assessments. In N.A. Gibble, G. McPherson, & B. Lane, eds., Shark management and conservation. Proceedings from the Sharks and Man workshop of the Second World Fisheries Congress, Brisbane, Australia, 2 August 1996, Dept. Primary Industries, Queensland, Aust: 72-73.

Compagno, L.J.V. 1998. Status of freshwater elasmobranchs. In N.A. Gibble, G. McPherson, & B. Lane, eds., Shark management and conservation. Proceedings from the Sharks and Man workshop of the Second World Fisheries Congress, Brisbane, Australia, 2 August 1996, Dept. Primary Industries, Queensland, Aust: 76-77.

Compagno, L.J.V. 1999. Chondrichthyes. In Gibbons, M. J., et al., The taxonomic richness of South Africa's marine fauna: a crisis at hand. S. African J. Sci. 95(1): 10, Tab. 1.

Compagno, L.J.V. 1999. Chapter 1. Systematics and body form. In W. C. Hamlett, ed.. Sharks, skates and rays. The biology of elasmobranch fishes. Johns Hopkins Press, pp. 1-42, fig. 1.1-1.15.

Compagno, L.J.V. 1999. Chapter 3. Endoskeleton. In W. C. Hamlett, ed.. Sharks, skates and rays. The biology of elasmobranch fishes. Johns Hopkins Press, pp. 69-92, fig. 3.1-3.8.

Compagno, L.J.V. 1999. Appendix. Checklist of living elasmobranchs. In W. C. Hamlett, ed.. Sharks, skates and rays. The biology of elasmobranch fishes. Johns Hopkins Press, pp. 471 to 498.

Compagno, L.J.V. 1999. `Kinds of sharks' (pp. 20-35), `Sharks and their relatives' (pp. 36-37), `Shark encounters in South Africa' (pp. 134-147), 'Conserving sharks (pp. 214-218)', and `Checklist of living sharks' (pp. 230-233), in Stevens, J. D., consulting ed., Sharks. Revised edition. Weldon Owen publishers, Australia, 1-240 pp, ill.

Compagno, L.J.V. 1999. Chimaeras. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1532-1537, figs.

Compagno, L.J.V. 1999. Diversity of cartilaginous fishes in the Western Cape and southwestern part of the Eastern Cape. Shark Research Center, South African Museum, SRC Report 19990318: 1-16, fig. 1-2.

Compagno, L.J.V. 1999. Checklist of cartilaginous fishes from Belize. Shark Research Center, South African Museum, SRC Report 19990804: 7 pp. Presented to FAO/ICLARM Belize workshop on Western Central Atlantic species sheets.

Compagno, L.J.V. 1999. Conservation status of the basking shark, Cetorhinus maximus, in southern Africa. Shark Research Center, South African Museum, SRC Report 19990920A, 10 pp. Prepared for the Chondrichthyian Working Group, Marine and Coastal Management (Sea Fisheries Research Institute).

Compagno, L.J.V. 1999. Conservation status of the whale shark, Rhincodon typus, in southern Africa. Shark Research Center, South African Museum, SRC Report 19990920B, 13 pp. Prepared for the Chondrichthyian Working Group, Marine and Coastal Management (Sea Fisheries Research Institute).

Compagno, L.J.V. 2000. An overview of chondrichthyan systematics and biodiversity in southern Africa. Trans. Roy. Soc. South Africa 1999 54(1): 75-120, fig. 1-9, tab. 1-2.

Compagno, L.J.V. 2000. Elasmobranchii, Holocephali. In J. E. Randall & Kelvin K. P. Lim, eds. A checklist of the fishes of the South China Sea. Raffles Bulletin of Zoology (supp. 8): 577-584.

Compagno, L.J.V. 2000. Species evaluations for Carcharhinus borneensis, C. hemiodon, C. leiodon, Dasyatis garouaensis, D. laosensis, Glyphis gangeticus, G. glyphis, Hemitriakis leucoperiptera, Himantura fluviatilis, H. oxyrhyncha, H. signifer, Leptocharias smithii, Megachasma pelagios, Notorynchus cepedianus, Poroderma africanum, Scylliogaleus quecketti, Taeniura lymma, Triakis acutipinna, T. megaloptera, Urogymnus asperrimus, U. ukpam. IUCN Species Survival Commission, Red List 2000, http://www.redlist.org and CD-ROM.

Compagno, L.J.V. 2000. Sharks, fisheries and biodiversity. Shark Research Center, South African Museum, SRC Report 20000221, 1-15. Prepared as part of a presentation for Shark Conference 2000, Honolulu, Hawaii, Feb. 21-24, 2000, for the Barbara Delano Foundation and published at: http://www.westpacfisheries.net/sharkcon/documents.

Compagno, L.J.V., & S. F. Cook. 2000. Species evaluations for Dalatias licha, Himantura chaophraya, Pristis microdon. IUCN Species Survival Commission, Red List 2000, http://www.redlist.org and CD-ROM.

Compagno, L.J.V., S. F. Cook & M. I. Oetinger. 2000. Species evaluations for Anoxypristis cuspidata, Pristis zijsron. IUCN Species Survival Commission, Red List 2000, http://www.redlist.org and CD-ROM.

Compagno, L.J.V., & M. Kroese. 2000. Species evaluations for Haploblepharus edwardsi, H. fuscus, Scyliorhinus capensis. IUCN Species Survival Commission, Red List 2000, http://www.redlist.org and CD-ROM.

Compagno, L.J.V., Freidhelm Krupp, & Kent E. Carpenter. 1996. A new weasel shark of the Genus Paragaleus from the northwestern Indian Ocean and the Arabian Gulf. Fauna of Saudi Arabia, 15, 1996: 391-401, figs. 1-4.

Compagno, L.J.V., & P.R. Last. 1999. Order Pristiformes. Pristidae. Sawfishes. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1410-1417, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Rhinobatiformes. Rhinidae (= Rhynchobatidae). Wedgefishes. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1418-1422, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Rhinobatiformes. Rhinobatidae. Guitarfishes. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1423-1430, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Rhinobatiformes. Platyrhinidae. Thornback rays. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1431-1432, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Torpediniformes. Narkidae. Sleeper rays. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1443-1446, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Torpediniformes. Hypnidae. Coffin rays. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1447-1448, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Torpediniformes. Torpedinidae. Torpedos. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1449-1451, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Myliobatiformes. Plesiobatidae. Giant stingaree. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1467-1468, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Myliobatiformes. Hexatrygonidae. Sixgill stingray. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1477-1478, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Myliobatiformes. Gymnuridae. Butterfly rays. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1506-1510, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Myliobatiformes. Myliobatidae. Eagle rays. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1511-1519, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Myliobatiformes. Rhinopteridae. Cownosed rays. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1520-1523, figs.

Compagno, L.J.V., & P.R. Last. 1999. Order Myliobatiformes. Mobulidae. Devil rays. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1524-1531, figs.

Compagno, L.J.V., P.R. Last, B. Seret, & M. R. De Carvalho. 1999. Batoid fishes. General remarks, key to families, and list of families and species occurring in the area. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1397-1409, figs.

Compagno, L.J.V., P. R. Last & J.D. Stevens. 2000. Species evaluation for Heteroscyllium colcloughi. IUCN Species Survival Commission, Red List 2000, http://www.redlist.org and CD-ROM.

Compagno, L.J.V., Mark A. Marks, & Ian K. Fergusson. 1997. Threatened fishes of the world: Carcharodon carcharias. Environmental Biology of Fishes 50: 61-62, ill.

Compagno, L.J.V., & J. A. Musick. 2000. Species evaluation for Pseudocarcharias kamoharai. IUCN Species Survival Commission, Red List 2000, http://www.redlist.org and CD-ROM.

Compagno, L.J.V., & V. H. Niem. 1998. Sharks. In Carpenter, K.E. and V.H. Niem (eds), 1998. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 2: 1195-1368 (173 pp).

Compagno, L.J.V., C. Simpfendorfer, J.E. McCosker, K. Holland, C. Lowe, B. Wetherbee, A. Bush, & C. Meyer. 1998. Sharks (Reader's Digest explores). Reader's Digest, 160 pp., illustr.

Compagno, L.J.V., John D. Stevens, & Peter R. Last. 1999. Australian spotted catsharks of the genus Asymbolus (Carcharhiniformes: Scyliorhinidae). Part 1: Description of three new species from Western Australia. In P. R. Last, Ed. Australian catsharks of the genus Asymbolus (Carcharhiniformes: Scyliorhinidae). CSIRO Marine Laboratories, Report (239): 2-18, fig. 1-3.

Cook, S.F., & L.J.V. Compagno. 1996. Preliminary field report and recommendations for structuring the freshwater and marine inshore elasmobranch project in Sabah, east Malaysia. Chondros res. rept. 9602A, 13 pp.

Cook, S.F., & L.J.V. Compagno. 2000. Species evaluations for Hexanchus griseus, Pristis pristis. IUCN Species Survival Commission, Red List 2000, http://www.redlist.org and CD-ROM.

Cook, S.F., L.J.V. Compagno & P. R. Last. 2000. Species evaluation for Pristis clavata. IUCN Species Survival Commission, Red List 2000, http://www.redlist.org and CD-ROM.

Cook, S.F., L.J.V. Compagno, & M. I. Oetinger. 2000. Species evaluation for Pristis perotteti. IUCN Species Survival Commission, Red List 2000, http://www.redlist.org and CD-ROM.

Cook, S.F., G. Zorzi & L.J.V. Compagno. 2000. Species evaluation for Bathyraja abyssicola. IUCN Species Survival Commission, Red List 2000, http://www.redlist.org and CD-ROM.

De Carvalho, M. R., L.J.V.Compagno, & P.R. Last. 1999. Order Torpediniformes. Narcinidae. Numbfishes. In Carpenter, K.E. and V.H. Niem (eds), 1999. FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Rome, FAO, 3: 1433-1442, figs.

Ebert, D. A. 1996. Biology of the sevengill shark, Notorynchus cepedianus, in the temperate coastal waters of southern Africa. S.African J. Mar. Sci. 17: 93-103, fig. 1-9.

Ebert, D. A., L.J.V. Compagno, & P. D. Cowley. 1996. A preliminary investigation of the feeding ecology of catsharks (Scyliorhinidae) off the west coast of southern Africa. S.African J. Mar. Sci. 17: 233-240, Fig. 1-2, tabl. 1-6. Recd. 1997.

Fergusson, Ian K, & L.J.V. Compagno. 2000. Distributional note on the dusky shark Carcharhinus obscurus from the Mediterranean Sea, with a first record from the Maltese Islands. In: B. Seret & J.-Y. Sire, eds. Proc. 3rd European Elasm. Assoc. Meet. Boulogne-sur-Mer, 1999. Paris: Soc. Fr. Ichthyol. & IRD, 2000: 57-65. Figs. 1-3; 1 tab.

Fergusson, I.K., L.J.V. Compagno, & M.A. Marks. 2000. Predation by white sharks Carcharodon carcharias (Chondrichthyes: Lamnidae) upon chelonians, with new records from the Mediterranean Sea and a first record of the ocean sunfish Mola mola (Osteichthyes: Molidae) as stomach contents. Environmental Biology

Tel: (021)808-3230

Fax: (021)808-2405

E-mail: bac@maties.sun.ac.za

THEME: SUSTAINABLE ENVIRONMENT THEME

PROGRAMME: SE: MARINE AND COASTAL RESOURCES

THRUST: MARINE AND COASTAL BIODIVERSITY AND CONSERVATION

TITLE: BIOGEOGRAPHY, SYSTEMATICS AND CONSERVATION OF SPONGE CRABS (FAMILY DROMIIDAE) OF SOUTHERN AFRICA

Overview of Important Findings and Implications for Science, Engineering and Technology

Although a final report is required, the project will only essentially be completed by the end of 2001, by which time more specimens would have been collected. This will enable me to submit the manuscripts which have been held up by the lack of fresh specimens for genetic analysis.

The project has been successful in that it has met the following goals:

1. The distribution, as well as centres for species richness and endemism for sponge crabs in SA are now known.

2. Morphological variation within and among the more common species is now known, and preliminary data exists on the genetic variation within and among the 17 endemic species. These data will be submitted in the form of MSS during 2001, following a 'last ditch effort' to acquire fresh specimens to boost the genetic database.

3. It has enhanced our knowledge of our endemic invertebrate fauna.

4. Collaboration between US and MCM has been good, and collaboration was also established with a researcher from New Zealand..

5. At least four published papers and one popular article will result from the study, and these should all be submitted/accepted in 2001.

The following goals were not met:

The training of a black student did not occur, owing to the loss of a Kenya student who was unable to get NRF funding to register for a MSc. Ms Nyonje elected to do a degree in Amsterdam, as she was offered a full bursary to do so.

Tel: 021-6503631

Fax: 021-6503301

E-mail: pcook@botzoo.uct.ac.za

THEME: SUSTAINABLE ENVIRONMENT THEME

PROGRAMME: SE: MARINE AND COASTAL RESOURCES

THRUST: MARICULTURE

TITLE: POTENTIAL FOR USE OF HATCHERY REARED ABALONE JUVENILES TO RE-SEED THE NATURAL ENVIRONMENT

Overview of Important Findings and Implications for Science, Engineering and Technology

A. SCIENTIFIC PROGRESS AND POSTGRADUATE STUDENTS

The project on the role of enteric gut bacteria in abalone was completed and resulted in two publications, 4 international symposium presentations and an MSc for Jean Erasmus. Work on the use of rotation diets for feeding abalone was completed by Brynn Simpson and resulted in one publication, two international symposium presentations and a successful MSc. Work on triploidy induction was completed, resulted in a successful MSc for Nigel Stepto and the results have been published in Aquaculture International.

Kevin Ruck has completed his work on sabellid infestations of abalone and his presentation generated considerable interest at the 3rd International Abalone Symposium (California). Ruck has subsequently been awarded an MSc for this work. After completing his MSc, Ruck took up employment as an abalone farm manager, but he still continues to work on systems designed at eradicating this parasite from farmed abalone. His work has produced 3 publications in international journals. In addition, we have formed a partnership with a research team from the University of California, Santa Barbara and members of that team visited South Africa in March 1998, to work with us on the sabellid problem. We expect at least two more publications to come out of that work.

Results of the reseeding/ ranching project have been very encouraging and were received enthusiastically at three completely independent international symposia (California, Norway, Cape Town). The results have been put into commercial operation and have resulted in the building of an abalone ranching operation at Port Nolloth. It also formed the basis of a successful MSc awarded to Jason Scott by our partner institution, the University of Stirling, UK. Research is, however, ongoing and formed the basis of a PhD project for Schalk de Waal, which was completed in 2000. Funding for this project was provided partly by Port Nolloth Sea Farms (our industrial partner) and partly by the Government of the Northern Cape.

Forensic work on the species level identification of abalone tissues has progressed very well and besides being reported at several international symposia, it has attracted co-operation from researchers in several other countries (Mexico, Australia, USA) as well as forming the basis of a co-operative research project with the forensic laboratory of the South African Police Services. We expect conservation authorities from several overseas countries to use our facilities and expertise for similar forensic work and this is already happening with the Mexican authorities, for whom we have completed a forensic investigation. The work formed part of a thesis that earned Neville Sweijd a PhD in 1999 and has also produced several publications in the international literature.

Ismail Matthews worked on the diatom diets of newly settled abalone postlarvae. He determined which species of diatoms are most useful as abalone food and also looked at the bacterial flora associated with these diatoms and determined the contribution that bacteria could make to larval nutrition. This work has been presented at international symposia and has also produced on publication in an international journal. His MSc was presented in 2000.

Kasturi Reddy's work on the toxicity of ammonia to abalone, has progressed well. She has determined toxicity levels for various size classes and determined the rate at which animals appear to become tolerant to ammonia. The possibility that acclimatization to ammonia is based on the production of some type of "stress proteins" is now being investigated. Kasturi will complete a PhD on this work in 2001. The results of this work were presented at the 4th International Abalone Symposium (February 2000) and will result in several publications.

A joint project with the Sea Fisheries Research Institute on the effects of Red Tide on abalone larvae, forms the basis of Lizeth Botes' PhD project. She has made considerable progress with identifying the organisms responsible for toxicity and results have already been presented at several local and international symposia as well as to the Abalone Farmers Association (who have given financial support to the project). Major funding for this project continues to be provided by SFRI. Lizeth Botes should complete her PhD by the end of 2001.

Rauri Bowie used molecular genetic techniques to investigate various aspects of abalone biology, the project being aimed at providing a molecular genetic basis for abalone conservation. Bowie received an MSc for this work in 1999. The work has been presented at two separate international symposia and two papers have been submitted to international journals.

Samson Omolo, a Kenyan student, undertook a project to look at biochemical aspects of transport stress in abalone which are exported live to markets in the East. Mortalities during transport are still unacceptably high and his project was designed to investigate the underlying biochemical reasons for this mortality. He isolated a number of enzymes that are responsible for the build-up of metabolic end-products that contribute to mortality, and the results of his work have greatly improved our understanding of the biochemical basis of transport mortality. He was awarded an MSc for this work during 2000.

Liesl Muller is involved in an MSc project, based at Aquafarm in Hermanus. She is investigating factors that lead to improved survival rates of newly settled abalone postlarvae. She will submit an MSc on this work at the end of 2001.

Carlos Ruiz has joined the team working on the effects of Red Tide organisms on abalone. The main focus of his MSc is to use molecular genetic techniques to identify the various species of planktonic organisms responsible for Red Tides.

Our co-operative initiative with the University of Stirling (U.K) resulted in the incorporation of two MSc students from Stirling (at no cost to us) into the research programme (Jason Scott and Shirley Plant). Both were awarded an MSc for the work that they did in this programme.

A number of Honours students (e.g. N. Bridel , M. Shearer and M. Griffiths) have undertaken abalone projects in co-operation with my research team.

B. IMPACT ON INDUSTRY

Most of the projects being carried out within this programme have a very direct and immediate relevance to the abalone farming industry. The projects outlined above are designed to address actual operational needs of the emerging industry and to improve the efficiency of operation of the farms. As the abalone farming industry is expected to expand to be worth about R100 million per year, the importance of operating at optimum efficiency is obvious. One of the main constraints to this is the lack of skilled manpower and students produced from my research group have been, and will continue to be, in high demand. In addition, very real questions being asked by the industry have been addressed by the group.

The potential danger posed by Red Tides, for example, could cause a serious negative impact on farms and the relevance of an early warning system to predict the occurrence of Red Tides is obvious. Both of the stress-related projects (Omolo and Reddy) are obviously of direct relevance to abalone farmers because of the decrease in growth rate that either form of stress could induce.

The basic feasibility of abalone ranching has already been established with preliminary experiments. With growth rates between 50 and 75% of the maximum obtained in onshore growout facilities on other abalone farms, the economic prospects are good, even with a small recovery rate (of seeded abalone) of less than 5. The fulfillment of this project will be directly within the stated mission of the NRF especially with regard to economic growth and social advancement of all South Africans. The ranching projects have already been taken up by industry and this form of abalone farming is expanding, several new applications to initiate ranches having been lodged. The genetic implications of ranching activities are important and are being addressed by the projects of Sweijd and Bowie. Also of direct and immediate relevance is the use of genetic results in forensic techniques and the results generated by this team have been taken up by the South African police as well as enforcement authorities in other countries such as Australia and Mexico. One of the most important constraints to the development of abalone farming in South Africa is the lack of sufficient suitable qualified manpower. . Students qualifying through this programme have no problem in finding jobs and, in fact, are often employed even before their studies are completed

Students undertaking projects in this programme are encouraged to feed their results back to the abalone farming industry. To facilitate this, items are included on the agenda of every meeting of the Abalone Farmers Association where individual researchers are given the opportunity to report on their results. This has applied particularly to the projects on Red Tides, transport stress and control of sabellids.

C. INTERNATIONAL COOPERATION

Dr R. Searcy-Bernal, Universidad Autonoma de Baja California, Mexico.

A 6 month sabbatical period was spent working with Dr Searcy-Bernal's research team on the diatom diets of newly settled abalone post-larvae. We developed techniques to investigate feeding activity in post-larvae and examined timing of dietary changes from bacteria to diatoms. We investigated diatom selectivity of post-larvae and determined rates of diatom ingestion, effects of diatom density and effects of antibiotics on post-larval growth rates. The results of these studies have formed the basis of two full-length research papers (in prep) and have also been reported to the South African abalone industry where some farms have already incorporated some of the suggestions coming from this research. Much of my work in Mexico was carried out in association with a working abalone farm "Abulones Cultivados" (Erinida, Baja California) with whom a close working relationship was developed.

Dr. Rodney Roberts (New Zealand)

A close relationship was also formed with Dr R. Roberts (New Zealand) who was also in Mexico for some time, and we have initiated some joint research projects with his team, New Zealand strains of diatoms suitable for abalone feeding already having been supplied to our research facilities at UCT.

Dr. Nick Elliott (Tasmania)

An exchange programme was initiated with Dr. Nick Elliott, whereby my research assistant (Neville Sweijd) spent 3 months working in Tasmania and Brad Evans from Tasmania spent the subsequent three months working in my laboratory in Cape Town. During this time, considerable progress was made on designing and implementing molecular genetic techniques for abalone and, overall, the exchange was extremely productive.

Following the very successful presentations given by my team at the 3rd International Abalone Symposium (Monterey, California) I was elected as Chairman of the International Organising Committee of the International Abalone Society and, as such, I was requested to organise and host the 4th International Abalone Symposium in Cape Town in 2000. Neville Sweijd was elected editor of the International Newsletter of the Society. During the 4th International Abalone Symposium, I was elected as President of the International Abalone Society and Neville Sweijd was elected as secretary.

D. S.E.T. AWARENESS

Members of my team (including the Grant Holder) took part in an SABC programme (50:50) which looked at the problem of the illegal exploitation of abalone in South Africa. Our forensic technique for the identification of abalone was discussed and, following this, we were approached by the "Tomorrow's World" team from the BBC. A similar programme which highlighted our forensic technique was subsequently shown on British television.

PAC also contributed to a subsequent SABC television environmental programme (The Green Machine) in which the over-exploitation of South Africa's abalone resource was again discussed. A subsequent SABC television programme in 2000, highlighted several aspects of mariculture, and PAC was again interviewed.

Publication of the forensic technique has also generated interest from the South African Police and we have now initiated a project to train members of the SAPS forensic laboratory in the use of this technique. We expect to work in co-operation with them on this project during 1998.

Several articles have appeared in the popular press including MusNews (newsletter of the South African Museum) and the newsletter of the Aquaculture Association of southern Africa.

Details of the forensic project, carried out in association with the South African Police Services were reported in the local press as well as in UCT's Monday Paper. Articles written by members of this team have appeared in both The Argus and Die Burger. For example, PAC was requested to provide the information for a recent article in "The Argus" which highlighted the current situation with regard to abalone farming in South Africa. Several members of the research team (e.g. Sweijd, Lopata) have also contributed newspaper articles on the abalone project. In addition, the project will be highlighted in an NRF newsletter during 2001.

Tel: 021-6503259/70

Fax: 021-6897573

E-mail: vernon@molbiol.uct.ac.za

THEME: SUSTAINABLE ENVIRONMENT THEME

PROGRAMME: SE: MARINE AND COASTAL RESOURCES

THRUST: MARICULTURE

TITLE: CHARACTErsaTION OF THE IMPACT, BOTH POSITIVE AND NEGATIVE OF MARINE BACTERIA ON MARICULTURE OF MARINE ORGANISMS AND THE USE OF RECOMBINANT DNA TECHNOLOGY FOR THE ENHANCEMENT OF SOUTH AFRICAN MARICULTURE ENTERPRISES.

Overview of Important Findings.

The Research Plan consisted of three sub-projects: Investigation of the role of melanin in the association between the pathogenic marine bacterium Vibrio cholerae and economically important shellfish; Investigation of the mechanisms of pathogenesis of bacterial epiphytes of Gracilaria gracilis and the use of recombinant DNA technology for the improvement of disease resistance in this red seaweed; and The role of enteric bacteria in the nutrition of the abalone, Haliotis midae. This Final Report will deal with each of these separately.

1. Investigation of the role of melanin in the association between the pathogenic marine bacterium Vibrio cholerae and economically important shellfish.

This project characterised how melanin is synthesised by Vibrio cholerae, with the eventual aim of investigating whether the pigment enables the bacterium (and consequently similar marine bacteria) to associate with economically important shellfish. This hypothesis was based on the ability of melanin to act as a scavenger of reactive oxygen intermediates (ROIs) that are generated during the animal's response to infection.

To achieve our objectives, the genes responsible for melanin biosynthesis in V. cholerae were cloned and identified. The primary gene encoded for a hydroxyphenylpyruvate dioxygenase (hppd), while the identity of the second gene product remains unknown. The hppd gene was extensively characterised using standard molecular techniques. The enzyme was purified and polyclonal antibodies were generated against Hppd. The antibodies were used to determine when translation of the hppd mRNA occurred, while RT-PCR was used to monitor transcription of the hppd gene in V. cholerae. Thus, we were able to show that although the hppd gene is transcribed throughout the growth phase of the life cycle of V. cholerae, translation only occurred well into the stationary phase of growth. We were also able to construct an hppd V. cholerae mutant which was used to show that pigmentation was able to protect the wild-type bacterium from oxidative stress due to ROIs.

Since the primary environmental signal responsible for melanin production in Vibrio cholerae was elevated salinity, we investigated the nature of the osmoregulatory machinery of this bacterium in order to determine how pigmentation is regulated. We cloned the ompB operon from V. cholerae and showed that it is structurally different to the ompB operons from other Gram negative bacteria such as Escherichia coli. We also identified a gene (greB) located upstream of the ompB operon that regulated the expression of the ompB operon in an unique way.

Finally, since our hypothesis supposes that melanin acts as an important defense system against ROIs, allowing the bacterium to infect shellfish, we investigated the nature of additional components that may be involved in protection against oxidative stress. One possibility would be catalase enzymes which are known to hydrolyse peroxide. Thus, we have cloned and characterised the catalase gene from V. cholerae and are currently characterising its role in protecting the bacterium against damage from ROIs and the extent to which this protection occurs in relation to the protection provided by melanin.

Unfortunately, the work has not progressed sufficiently for us to tackle the next phase which will be investigating whether there is indeed a link between pigmentation in Vibrio cholerae, and related bacteria, and their association with commercially important shellfish. This will become feasible once various mutant strains have been generated.

2. Investigation of the mechanisms of pathogenesis of bacterial epiphytes of Gracilaria gracilis and the use of recombinant DNA technology for the improvement of disease resistance in this red seaweed.

This sub-project is aimed at gaining an understanding of the nature of the bacterial pathogens and the mechanism whereby they cause disease in the commercially important agarophyte Gracilaria gracilis at Saldanha Bay. The project also is concerned with the ability of the seaweed to protect itself from infection.

We have shown that bacterial epiphytes that are agarolytic are able to cause bleaching and thallus degradation. We were able to identify bacterial pathogens of G. gracilis using a pathogenicity assay that we developed. The assay makes use of axenic seaweed and satisfies all the requirements of Koch's postulates for the identification of pathogenic organisms. Two of the pathogens were characterised extensively and shown to belong to the genus Pseudoalteromonas. The agarase gene has been cloned from both strains and analysis of the genes revealed that they are structurally different, with the agarase from Pseudoalteromonas gracilis active at temperatures of up to 55oC. This is an important finding as disease is only induced during the summer months when the water temperature at Saldanha Bay is raised and the upper water column becomes oligotrophic.

Antibodies generated to the purified agarase from P. gracilis were used in an immuno-gold study which clearly showed that the bacterial agarase was associated with the mucilage component of the algal cell wall and that it was responsible for the extensive degradation seen in infected seaweed.

We developed a cDNA-AFLP technique for identification of algal genes that are up-regulated following infection by a bacterium pathogenic to the seaweed. Using this technique, we were able to clearly demonstrate that the seaweed responds to infection by expressing a number of genes that may encode for proteins that are involved in a disease resistance response. A number of these gene fragments were isolated, cloned and sequenced. From a Blast search of the Genbank database, we were able to show that at least two of the cloned gene fragments do indeed code for putative pathogen response proteins, indicating that G. gracilis possesses a defense system for protection against pathogens (similar to that of higher plants).

3) The role of enteric bacteria in the nutrition of the abalone, Haliotis midae.

This sub-project is focussed on the digestive role played by enteric bacteria of the South African abalone Haliotis midae. Since abalone are grazers that rely on seaweed for their nutritional requirements, it is important to know whether bacteria colonising their gut enhance the digestion of seaweed.

We have isolated a variety of bacteria from the digestive tract of H. midae and characterised these bacteria in terms of the genus that they belong to. We have employed a ribotyping protocol to genetically fingerprint the bacteria that make up the enteric community so that we will be able to identify specific bacteria colonising the abalone digestive system.

We have screened the bacteria for the ability to degrade a variety of polysaccharides that are found in the seaweeds that are commonly fed to farmed abalone. Thus, we have shown that the enteric bateria colonising the gut of the South African ablaone are capable of hydrolysing agar, alginate, carboxy methyl cellulose (CMC), carrageenan and laminarin. We also developed a protocol for rendering abalone gnotobiotic (bacteria free) and this allowed us to investigate the role played by the polysaccharolytic bacteria colonising the abalone digestive tract in terms of their contribution to digestion of ingested eaweeds. Thus, we were able to show that, although the abalone is capable of digesting CMC, laminarin, carrageenan, alginate and agar, bacterial polysaccharolytic activity clearly enhanced the rate of polysaccharide hydrolysis.

Besides their importance in degrading seaweed components, we have shown that abalone enteric bacteria are also important as a source of protein. This is significant since Ecklonia maxima, the most commonly used seaweed for feeding farmed abalone in the Western Cape, is notoriously poor in protein content.

Implications for SET in South Africa.

This research plan has resulted in two PhD theses being produced, with another two currently being completed. There has also been one MSc student and a number of BSc(Hons) students who have participated in this research plan. Of the students involved in this research plan, the majority have been black and/or female. Five research papers have been published in international journals, while another five papers are currently in preparation. The research has also been presented at a number of national and international conferences. Seven postgraduate students have had the opportunity to attend and present their research at the following international conferences: Second International Symposium on Abalone Biology, Fisheries & Culture (Hobart, Tasmania), 7th International Conference of the International Association of Applied Algology (Knysna, South Africa), International Marine

Biotechnology Conference '97 (Sorrento, Italy), 4th International Abalone Symposium (Cape Town, South Africa), 5th International Marine Biotechnology Conference (Townsville, Australia) and the 17th International Seaweed Symposium, (Cape Town, South Africa).

The sub-project dealing with disease resistance in Gracilaria gracilis has resulted in a France-South Africa co-operative grant being awarded to foster collaboration between my laboratory and the research group led by Dr Philippe Potin of NRS/Laboratoires Goëmar S.A., which is part of Prof Kloareg's group at Roscoff. It should be noted that we are currently considered to be one of the leading research groups in the newly emerging field of phycopathology. This was clear from the comments and encouragement that we received in response to our research papers that were presented at the 17th International Seaweed Symposium. Unfortunately, it seems that despite all this, our funding for seaweed research has been stopped by the NRF, ostensibly due to the lack of large scale seaweed farming in South Africa. In response to this, it should be noted that all new technologies are preceded by good fundamental science (as was the case in the development of abalone farming technology which led to commercial farming of Haliotis midae in South Africa). Unless the disease problem can be addressed, commercial production of G. gracilis will never become a reality in Saldanha Bay. In addition to this, it is highly likely that on-shore cultivation of G. gracilis will be undertaken shortly to produce abalone feed. Once again diseases affecting this seaweed will need to be characterised and strategies developed to overcome outbreaks of infection.

The sub-project dealing with the role of enteric bacteria in digestion of seaweed ingested by abalone has proved highly successful in that close links with the abalone industry in South Africa have been developed, specifically through the Abalone Farmers Association of Southern African. The research has significant commercial applications for improving abalone cultivation and consequently I cannot go into detail in this report due to contractual obligations currently being negotiated.

Finally, the success of this research plan in terms of establishing Marine Biotechnology in South Africa has resulted in my being elected as the South African representative on the International Organising Committee which is responsible for the International Marine Biotechnology Conferences held every three years. In addition, I have been successful in negotiating African membership in the European Society for Marine Biotechnology. It is hoped that by linking African scientists with established scientists involved in Marine Biotechnology, expertise and increased critical mass will result in Marine Biotechnology being established as an important thrust that will result in new technologies and sustained resource management in coastal African countries.

Tel: (046)-6038264

Fax: (046)-6225109

E-mail: m.davies-coleman@ru.ac.za

THEME: SUSTAINABLE ENVIRONMENT THEME

PROGRAMME: SE: MARINE AND COASTAL RESOURCES

THRUST: COASTAL COMMUNITIES AND LIVING RESOURCES

TITLE: MARINE INVERTEBRATE AND ALGAL RESEARCH

Our primary area of research interest has been, and continues to be, the chemistry of South African marine natural products in particular the bioactive metabolites produced by four groups of soft-bodied marine invertebrates ie. sponges, octocorals, molluscs, and ascidians. Given the abundance and immense diversity of South Africa's marine resources and the long tradition of natural product research in this country it is somewhat surprising that South African marine natural products chemistry research has been largely neglected by South African scientists. Therefore on the completion of my post-doctoral training with leading international marine natural product chemist Professor John Faulkner at Scripps Institution of Oceanography (1991), I realised that a study of the natural products chemistry of South African marine organisms was a potentially rewarding and relatively untapped research opportunity.

In my attempts over the last seven years to establish a South African presence in the international marine natural products research field I have organised financial and material support from the FRD (NRF), Rhodes University, SmithKline Beecham (USA), the National Cancer Institute (USA) and Dow AgroSciences (USA). This financial support has led to invaluable, rewarding and sustained collaborations over the last six years with local and international researchers including Professor Faulkner (SIO, USA), Professor Gerwick (OSU, USA) Dr Cragg (NCI, USA), Dr Colin (CRRF, Palau), Dr Chapin (Dow AgroSciences, USA)Dr Burgoyne (Inflazyme,Canada)Dr Barrows (University of Utah, USA)Professor Garson(University of Queensland), Dr Carte and Dr Eggleston (SmithKline Beecham USA and UK) Dr Kelly (NIWA, New Zealand) Dr Schleyer (ORI, Durban), Dr Coetzee (UPE, Port Elizabeth), and Dr Gibbons (UWC, Cape Town).

Although my annual funding for research (student stipends excluded) has rarely exceeded US$10 000 my research group has isolated, identified and published the structures of over fifty new natural products from South African marine organisms in 17 research papers in international journals. In addition to the 17 papers pertaining directly to South African marine natural products I have also been a co-author on a further 6 international publications relating to the natural product chemistry of marine organisms from Madagasca, Antarctica, and the South Pacific. Finally, I have co-authored 3 natural product reviews and 11 papers in plant natural product chemistry. My research group is the only African based research group publishing in the field of marine natural product chemistry.

My research group has made 8 presentations at five international conferences and 21 at eight local conferences. I have given six lectures at five different research institutions in the USA and four around South Africa. I have also given public lectures at schools, the National Science Festival and both the Port Elizabeth and East London Museums.

I have successfully supervised three PhD and one MSc student in marine natural products chemistry and have co-supervised one PhD in organic synthesis. A further two PhD's and one MSc are currently in training. Three of my research students have won gold medals for their research presentations at Eastern Cape Post Graduate Research Seminars and one also won the best poster award at a recent South African Marine Sciences Symposium. Two of my PhD students went to the USA for post doctoral training on the completion of their PhD's, one was appointed to a senior position at Lever Brothers and the fourth joined the lecturing staff at Rhodes University. This year my one MSc student successfully completed her PhD at Cambridge University in the UK.

Our research collections of invertebrates have been made off Cape Town, the Tsitsikamma National Park, Algoa Bay, Port Alfred, Coffee Bay, Aliwal Shoal and Mozambique. We have contributed significantly to the research effort in the Tsitsikamma National Park through the donation of ca. R30 000 of SCUBA diving equipment from SmithKline Beecham and the publication of 5 research papers describing the chemistry of bioactive natural products from Tsitsikamma invertebrates(two further papers are in preparation).The work in the Tsitsikamma also led to the discovery of a new genus of latrunculid sponge.

Although our recent three year old anti-cancer collaborative drug discovery programme with the National Cancer Institute in Algoa Bay, has not as yet yielded any new anti-cancer drugs it has led to the resuscitation of UPE's Research Diving Unit, supported an ascidian taxonomy PhD project at UPE and has provided the most comprehensive collection and complete record (including underwater photographs and detailed database)ever made of invertebrate and algal life in Algoa Bay. The collection of over 800 marine invertebrates and algae will be fully identified by 2002. The Algoa Bay collection has also provided PhD project material for three students (two at Rhodes and one at UWC).

The necessity to give research students as broad a training as possible has resulted in the diversification of our research effort to include natural product synthesis and marine chemical ecology. We have made substantial progress in both these areas and recently published the first ever synthesis of a South African sponge natural product.

In conclusion I believe we have made a substantial contribution to the understanding of the immense biodiversity and related pharmaceutical/agrochemical potential of marine invertebrate and algal life off the south east Coast of South Africa. Although no marketable pharmaceuticals or agrochemicals have emerged as yet from South African marine organisms, the international interest in our work makes it important that the established momentum and expertise is maintained through continued NRF support.

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