The Western Indian Ocean represents ca. 8% of the world's oceans but generates only 4% of the global industrial catch. This region is also home to a great proportion of the world's population, living in developing countries with a high dependence on marine resources. Trends in the declared landings of marine resources from the Western Indian Ocean suggest that this ocean may be approaching its maximum harvest potential of ca. 4 Mt per annum, but underreported artisanal catches complicate more-detailed analyses. There is a growing demand for 'new resources' to make up for declining stocks, while several large fluctuations are linked to changes in market demand and over exploitation. Artisanal fisheries in the region are highly diversified. Preliminary results are presented of a project that evaluates the conservation status and sustainable management practices in 168 different fishery types. It is concluded that the majority of the region's artisanal fisheries are not adequately supported by scientific information and that management strategies need to be improved if the enormous development challenges of East African countries are to be met.

Growth rings (GR) were counted in vertebrae of 69 female (56–221 cm precaudal length; 3–238 kg) and 54 male (57–216 cm; 3–180 kg) C. leucas. Annual GR deposition could not be confirmed by centrum edge analyses but was assumed on the basis of ‘mark–recapture’ analysis of 10 sharks held captive for between 2.2 and 20 years in an aquarium. GR counts indicated that the largest female and male were 32 years (221 cm) and 29 years (216 cm), respectively and the smallest mature female and male were 14 years (197 cm) and 25 years (196 cm). Length at 50% maturity was 193 cm (21 years) and 190 cm (20 years) for females and males, respectively. Maximum age is >50 years, and the two specimens (216, 217 cm) that have been held in the aquarium for 20 years are both estimated to be >29 years. Von Bertalanffy parameters for the combined sexes were L∞ = 230 cm, k = 0.071 year–1, t0 = –5.12 years, and Gompertz parameters were w0 = 24 kg, G = 2.86, g = 0.046 year–1.

Largetooth sawfish Pristis pristis and green sawfish P. zijsron were not uncommon in catches made in KwaZulu-Natal (KZN) on the east coast of South Africa in the mid part of the last century but apparently have disappeared from this area. This paper traces the decline in sawfish catches from 1951 and assesses the current population status and local extinction risk, based on historical and current records up to 2012. Records were collected from research surveys, literature, media and museum specimens, and through contacting researchers and conservation managers who have worked in KZN coastal and estuarine areas. A total of 150 green sawfish, 7 largetooth sawfish and 89 unidentified sawfish records were located. Most sawfish (115) were caught during a four-year (1967-1970) gillnetting survey conducted by the Oceanographic Research Institute in the St Lucia estuarine system while 91 were caught in the bather protection nets installed and maintained along the KZN coast by the KwaZulu-Natal Sharks Board. Sawfish ranged from 63 to 533 cm total length (TL). Sawfish caught in the estuarine environments (mean TL 162 cm [SD 72], n = 95) were significantly smaller than those caught in the inshore marine environments (mean TL 310 cm [SD 109], n = 83), confirming the importance of estuaries as pupping and nursery areas. The St Lucia estuarine system, given the high abundance of sawfish, was determined to be the most important nursery area in KZN. The last sawfish encountered in KZN, which was not identified to species level, was caught in the bather protection nets in 1999 and released alive. Extinction probability analysis indicates that sawfish no longer occur in KZN waters. Anthropogenic changes to the St Lucia estuarine system, as well as to other KZN estuaries, gillnetting for bather protection, and illegal fish harvesting, coupled with a non-adaptive life-history style, may have precipitated the disappearance of sawfish from KZN waters.Online supplementary material: The complete list of records and specimens for largetooth sawfish Pristis pristis and green sawfish P. zijsron located by consulting various data sources, primary literature, media, museums and local conservationists and scientists is available online in Supplementary Appendix S1 at http://dx.

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