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South Africa has taken an iterative approach to marine ecosystem mapping over 18 years that has provided a valuable foundation for ecosystem assessment, planning and decision-making, supporting improved ecosystem-based management and protection. Iterative progress has been made in overcoming challenges faced by developing countries, especially in the inaccessible marine realm. Our aim is to report on the approach to produce and improve a national marine ecosystem map to guide other countries facing similar challenges, and to illustrate the impact of even the simplest ecosystem map. South Africa has produced four map versions, from a rudimentary map of 34 biozones informed by bathymetry data, to the latest version comprising 163 ecosystem types informed by 83 environmental and biodiversity datasets that aligns with the IUCN Global Ecosystem Typology. Data were unlocked through academic and industry collaborations; multi-disciplinary, multi-realm and multi-generational networks of practitioners; and targeted research to address key gaps. To advance toward a more transparent, reproducible and data-driven approach, limitations, barriers and opportunities for improvement were identified. Challenges included limited human and data infrastructure capacity to collate, curate and assimilate many data sources, covering a variety of ecosystem components, methods and scales. Five key lessons that are of relevance for others working to advance ecosystem classification and mapping, were distilled. These include (1) the benefits of iterative improvement; (2) the value of fostering relationships among a co-ordinated network of practitioners including early-career researchers; (3) strategically prioritizing and leveraging resources to build and curate key foundational biodiversity datasets and understand drivers of biodiversity pattern; (4) the need for developing, transferring and applying capacity and tools that enhance data quality, analytical workflows and outputs; and (5) the application of new technology and emerging statistical tools to improve the classification and prediction of biodiversity pattern. South Africa’s map of marine ecosystem types has been successfully applied in spatial biodiversity assessment, prioritization to support protected area expansion and marine spatial planning. These successes demonstrate the value of a co-ordinated network of practitioners who continually build an evidence base and iteratively improve ecosystem mapping while simultaneously growing ecological knowledge and informing changing priorities and policy.

Commercial fishing in False Bay, South Africa, began in the 1600s. Today chondrichthyans are regularly taken in fisheries throughout the bay. Using a combination of catch, survey and life history data, the occurrence and long-term changes in populations of chondrichthyans in False Bay are described. Analyses of time series data from five fishing methods between 1897 and 2011 provided trends in relative abundance. Of the 37 species found in False Bay, 25 showed no significant trends for any fishing method. Of the 12 species and two genera with catch trends, four showed a common trend across methods, two increasing (Mustelus mustelus and Carcharhinus brachyurus) and two decreasing (Galeorhinus galeus and Raja spp.), while another two species (Triakis megalopterus and Isurus oxyrinchus) showed highly significant declines in one method only. A productivity index was used in conjunction with information on species distribution, catch frequency and trends in abundance to assess the vulnerability of False Bay chondrichthyans. Among the various habitats and depth strata, the surf-zone has been most impacted by exploitation, whereas the conservation of deep-water, soft-sediment species has benefited from the ban on trawling in False Bay implemented in 1928. Continued monitoring using catch data from beach-seine, recreational shore-angling and the commercial linefishery is recommended, along with improved species identification.Key words: chondrichthyans, elasmobranchs, exploitation, vulnerability, population trends, conservation.

Wiley-Blackwell, 9600 Garsington Road, Oxford, OX4 2DQ, UK384 pages, hardcoverISBN 978-1-4051-9297-2. Price £120.00/€144.00/$170.17African Journal of Marine Science 2011, 33(3): 347–348

Includes bibliographical references (leaves 163-180)., In multispecies fisheries knowledge, personnel and funding limitations often create the dilemma over which species should be the first to receive management and research attention. This thesis uses a Multi-Criteria Decision Analysis approach to prioritize 176 South African linefish species on the basis of a number of criteria indicating conservation and socio-economic importance. Each species importance was assessed from the points of view of (1) conservation, (2) each fishery sector separately and combined and (3) the overall combined conservation and sectorial importance. Relative scores within each of the fishery sectors were dominated by two or three species such that the scores separating the remaining species from each other were small. On the whole, the top species included those most important in each sector, biogeographic region and in terms of conservation. The separate and overall ran kings should assist in the development of broadly acceptable management strategies for different fish. Catch data for 129 of 255 functional estuaries on the South African coastline were reviewed and the relationships between fish catch and estuarine size, type and biogeographical region analysed using simple and multivariate models. Estuary size alone explained over 80% of the variation in catch in the warm temperate region and over 90% of the variation in catch in the cool temperate and subtropical region. Further analysis of the two main estuarine types (permanently open and temporarily open/closed estuaries) revealed higher productivity for the permanently open systems. Both estuarine size (ha) and type (5 types) were used to explain catches using general linear models. The models were able to explain 82-98% of the variance in catches. The total estuarine catch in South Africa was estimated at 2 480 tons per annum with a total value of R748 million, of which 99% could be attributed to recreational angling. Estuarine contribution to the inshore marine fisheries was estimated at approximately R846 million per year with estuarine dependent species comprising 83% of the catch of the recreational shore and commercial seine and gillnet fisheries and only 7% of the catch of the recreational spearfishery and commercial and recreational boat fisheries. Total value of estuarine and estuary-dependent fisheries was estimated to be R1.594 billion per annum in 2008 rands. The cool-temperate Olifants and warm temperate Breede estuaries on the west and south coasts of South Africa have both seen a >35% reduction in mean annual runoff (MAR) from a historical reference condition to the present day with a >60% reduction possible under future development. With almost no exceptions, the Olifants Estuary fish assemblage has seen an overall 20% decrease in abundance from reference to the present day and will gradually decline to 55% of reference with a predicted future 60% reduction in MAR. Consequently, future reductions in flow are likely to see the Olifants Estuary progressing towards a low biomass, low diversity, marine-dominated system. In contrast, with the exception of some key exploited species, fish abundance in the Breede Estuary has increased by 6% from reference to the present day and is likely to increase to 115% of reference with future reductions in flow. In all, the fish assemblage will experience a gradual change from a relatively high-diversity low-abundance freshwater-rich system under historical flow conditions to a high-diversity, highabundance, marine-dominated system with future reductions in flow.

Bibliography: pages 108-123., This study was initiated in response to allegations by the conservation lobby that the commercial beach-seine fishery in False Bay was jeopardizing fish stocks and detrimentally affecting the ecology of the Bay. Its main aims were to quantify the current catch and place it in an historical perspective, to describe seasonal patterns in catches and effort and to assess the impacts of netting on juvenile fish and benthic organisms. The overall objective was to provide a "scientific" basis for the resolution of the controversy surrounding this fishery.

The Cape Elephant fish (Callorhinchus capensis) and two common sand shark species (Rhinobatos annulatus and Rhinobatos blochii) were caught off False Bay and Saldanha Bay and surveyed for their parasite community in 2013 and 2014. The surveys were used to build species accumulation curves (SAC) and calculate biodiversity indices, particularly, rarefied species richness, Shannon Weiner's diversity index, Simpson's index and Pielou's J index. The biodiversity indices were correlated with the host's biological data and parasite infection data, to determine the parasite community structure and provide insight into the host's community structure. The parasites identified in C. capensis (n=19) include a cestode (Gyrocotyle plana), two monogeneans (Callorhynchicotyle callorhynchi and Callorhinchicola multitesticulatus) and an isopod (Anilocra sp.). The cestode was the most prevalent at 68.4 % and the monogenean, C. callorhynchi was the most abundant (1.68 ±0.78) and had the highest infection intensity (4.00 ±1.45). The SAC and biodiversity measures indicate a uniform parasite community across the host population, suggesting a highly interactive shark community. Conversely, Rhinobatos annulatus (n=19) and R. blochii (n=17) had very limited parasite infection with two species of nematode found infecting the stomach (Proleptus obtusus) and encysted in the kidneys (Ascaris sp.) and a copepod species (Clavelottis sp.) found infecting the gills. Proleptus obtusus was the most prevalent (31.6 % and 29.4%), the most abundant (1 ±0.37 and 3.68 ±2.76) and had the highest mean infection intensity (3.17 ±0.4 and 14 ±1.5). A cestode (Trilocularia sp.) was found infecting three specimens of R. annulatus from False Bay. The SAC and biodiversity indices combined with the limited parasite infection indicate a non-uniform parasite community across the host population, suggesting an isolationist population. Within the parasite community discovered, a potential biological indicator for heavy metal accumulation was identified to determine the levels of heavy metal pollution within these two anthropogenically impacted bays. Gyrocotyle plana and Proleptus obtusus were chosen as potential indicators due to their high prevalence and the close relationship they have with their hosts. The results support the use of higher trophic level animals as biological indicators. The results also indicate that G. plana is an incredibly good accumulator of certain metals, particularly As (4073.52 ± 5561.54 μg/g), Mn (522.16 ± 578.21 μg/g), Pb (64.87 ± 101.7 μg/g), Ti (1821.42 ± 1348.16 μg/g), and Zn (12439.57 ± 9743.60 μg/g). Unfortunately water and sediment samples were not tested, however, concentrations were compared to baseline values, and the accumulation of these metals are orders of magnitude above the surrounding environment. Proleptus obtusus did not significantly accumulate metals from its surrounding environment. These results show that parasites can be used to infer their own and their host's community structure and confirm their usefulness as indicators of pollution in marine ecosystems.