Mako sharks are targeted in the pelagic shark longline fishery, and caught as bycatch in the tuna/swordfish longline fishery.

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1 SANBI IDentifyIt - Species Shortfin Mako Shark - Isurus oxyrinchus Family Lamnidae Geographic location / distribution Habitat: Makio's are oceanic, pelagic species, distributed in temperate and tropical waters of all oceans. They prefer temperatures of C (seldom occurring in waters below 16 C), and occupy the area between the sea surface to 450 m, occasionally reaching greater depths. Fishery Mako sharks are targeted in the pelagic shark longline fishery, and caught as bycatch in the tuna/swordfish longline fishery. Size limits Southern bluefin tuna >6.4kg Bigeye tuna >3.2kg Yellowfin tuna >3.2kg Swordfish >119cm LJFL / >18kg dressed Marlins >210cm LJFL Stock status No conclusions from assessment studies, with some evidence that the stock could be over-exploited. Fisheries management Mako sharks fall within the management of the large pelagic fishery, and are therefore managed by Regional Fisheries Management Organisations. South Africa is a member of ICCAT and a co-operating non-member of IOTC and CCSBT. Although RFMO's manage high seas fisheries, management recommendations and resolutions are implemented by South Africa through national legislation and permit conditions. The South African Shark fishery was actually banned at the end of 2009 but vessels are allowed to fish on an exemption permit in 2010/2011. Mako shark are commercially valuable as opposed to the blue sharks. High prices create incentives to target mako sharks (sold as sakamuri) in the absence of tuna/ swordfish in a particular area. The Tuna fishery is managed by a Total Allowable Effort (TAE), meaning that instead of setting a limit on the catch, a limit is set on the number of rights holders allowed to catch tuna. Currently there is a limit of 200 rights holders in SA (including pole and longline). Longlining is not a very selective form of fishing and many species are caught incidentally on the the hooks. Bycatch species in this fishery include: billfishes (swordfish, marlins etc), seabirds, turtles and sharks. Recent assessments show that eleven species of seabird, four species of turtle and 20 species of shark are caught incidentally by this fishery. The FAO estimates that approximately 28% of the catch is discarded. Local studies indicate that discards comprise approximately 22% of the catch. Bycatch restrictions therefore exist to protect vulnerable species like sharks: The bycatch of billfish cannot exceed 10% of the total tuna catch A precautionary catch limit of 25 seabirds has been set for tuna longline vessels, after which further management restrictions are enforced Shark fins need to be landed with their trunks, with the fins not exceeding 5% of the weight of the trunk on foreign vessels according to ICCAT and IOTC, but 8% on SA vessels. Any Bigeye, Swordfish or Southern Bluefin tuna landed must be accompanies by the relevant RFMO (ICCAT, IOTC or CCSBT) catch statistical document. Maturity and Sizes Although biological data on the age and growth of shortfin mako in Atlantic waters is incomplete, studies show mako's

2 reach maturity at cm. However, much information is still unknown, except that mako's are born approximately 70cm in length and grow up to 400cm. Physical description Identifying characters Conical, pointed snout Caudal fin crescent shaped with large caudal keels Length of pectoral fins is less than head length Dark blue to cobalt blue on back, white belly and ventral surfaces Long exposed teeth without serrations Long gill slits Other similar species Carcharhinus brachyurus - Bronze Whaler Carcharodon carcharias - Great White Shark Prionace glauca - Blue Shark References FAO fact sheets Fishery Resource Monitoring System Fact Sheets: ICCAT Tuna fact sheets. ICAT Manual. January FAO Fisheries and Aquaculture Department. Biological characteristics of tuna/individual species sheets. FI Institutional Websites. Text by Michel Goujon and Jacek Majkowski. In: FAO Fisheries and Aquaculture Department[online]. Rome. Updated 24 February [Cited 30 November 2010]. Website: Shortfin Mako Shark Photo: Mark Conlin / swfsc.noaa.gov Photographer: P Mark Conlin / swfsc.noaa.gov Copyright/Website: Mark Conlin / swfsc.noaa.gov / Public Domain

3 Photo: NOAA-PIRO Public Domain Photo: NOAA - public domain Photo: NOAA - NMFS - Public Domain Shortfin Mako head. Photo: Public Domain.

4 Photo: Mark Conlin Photo: NOAA-SWFSC Shortfin Mako Jaw. Photo: Didier Descouens.

5 Shortfin Mako teeth. Photo: Joxerra Aihartza Photo: C. Da Silva Landed, headed & gutted without fins, the trunk can be differentiated from blues as it is a robust, round trunk. Usually partially gutted, with a very red meat. Nicola Okes Photo:

6 General Shark Identification Copyright/Website: TRAFFIC

7 Shark Trade Products Copy right/website: TRAFFIC Copyright All rights reserved.