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16 A. B. M. MOORE ET AL. between maternal L T and litter size (Pearson r = 0·785, n = 8, P0·05). The L T of the embryos and that of the smallest animals recorded in landings indicate that birth size locally is c. 36–38 cm L T . A female R. oligolinx of 67·4 cmL T contained three embryos (males of 23·6 and 28·2 and a female of 26·2 cmL T ). An 83·5 cm L T M. mosis from Abu Dhabi contained 11 fully formed embryos (six males 25·5–28·4 cmL T ; five females 26·5–26·7 cmL T ). In addition to five embryos, the right uterus also contained a yolk-coloured oval ovum of solid waxy material c. 5 cm long, which is unusual (A. Henderson, pers. comm.). Other notable opportunistic observations from females of elasmobranch species whose biology is poorly known were an aborted recently formed candle (i.e. eggs within a common shell) from a 180 cm L T bowmouth guitarfish Rhina ancylostoma Bloch & Schneider 1801 (Abu Dhabi); mature oocytes of ≤1·4 cm diameter in a 23·2 cmW D scaly whipray Himantura imbricata (Bloch & Schneider 1801) in Qatar; several female cowtail stingray Pastinachus sephen (Forsskål 1775) of ≥61 cm W D with emergent fully formed embryos (Kuwait 2008); several females of Rhinoptera sp. (probably Rhinoptera jayakari Boulenger 1895) of ≥80 cm W D with emergent fully formed embryos and aborted embryos of 22·5–28·5 cmW D (Kuwait 2008). FISHERIES, BY-CATCH, DISCARDING AND UTILIZATION The majority of elasmobranchs recorded in this study were landed by small (c. 7–10 m) open speedboats operating gillnets to target teleosts in local, coastal waters. In addition to small gillnetters, larger (c. 15–20 m) dhows also operated, targeting teleosts with either hemispherical wire fish traps (gargoor) or gillnets, but these vessels appeared to contribute less to the overall elasmobranch landings recorded. In Abu Dhabi, these dhows (reportedly operating in Gulf waters) also landed large elasmobranchs from hook-and-line fishing as a targeted but apparently supplementary activity. While all quayside landings recorded at Abu Dhabi were caught in The Gulf, the retail market sold both locally caught elasmobranchs and those imported overland originating from the Gulf of Oman. A small number of small sharks at each survey location had apparently been caught by handline, presumably opportunistically during gillnetting. In addition, recent footage from Bahrain demonstrated that large gargoor (c. 250 cm height) can occasionally capture quite large (c. 150 cm L T ) rhynchobatids (A. B. M. Moore & R. Peirce, pers. obs.). All elasmobranchs recorded were landed and marketed whole, with no direct evidence of removal of fins at sea. Fins were observed being removed from sharks and guitarfishes in Kuwait and Qatar both by fishers at the quayside and by stallholders upon sale for consumption, apparently for onward sale. Large sharks and guitarfishes landed whole in Abu Dhabi were transported overland to other Emirates for processing, presumably for the fin market (A. B. M. Moore pers. obs.; R. Jabado pers. comm.). While prices were not recorded, sharks were marketed at relatively low prices compared to teleosts. Rays appeared to be of particularly low value and catches in Kuwait were commonly observed being discarded for disposal (either back at sea, in the harbour or in refuse), although rays picked from the gillnets of incoming vessels at Doha Corniche, Qatar, were always marketed. Rhynchobatid guitarfishes were the only commonly encountered batoid taxa that were apparently of some value, both as meat and apparently for fins. Weather conditions appeared © 2012 The Authors Journal of Fish Biology © 2012 The Fisheries Society of the British Isles, Journal of Fish Biology 2012, doi:10.1111/j.1095-8649.2011.03210.x
ELASMOBRANCHS IN KUWAIT, QATAR AND ABU DHABI 17 to have a notable effect on elasmobranch discarding practices in Kuwait, with the unsettled weather in April 2011 resulting in nets being emptied at the quayside rather than at sea. This factor is likely to explain the high number of low-value C. arabicum and R. granulatus recorded in 2011. OVERVIEW DISCUSSION The current study is the first detailed, large-scale survey of the diversity, biology and fisheries of Gulf elasmobranchs and provides a foundation for more refined characterization. This is despite its limitations in terms of seasonal coverage and relatively small sample size compared with other recent works sampling elasmobranch landings at (sub-) tropical locations (White & Dharmadi, 2007; Bizarro et al., 2009). Detailed assessment of reproductive status was not recorded in this study. The findings confirm that the elasmobranch landings in the parts of The Gulf covered by this survey are dominated by a few species of common, small carcharhinids which are caught largely as by-catch, and the species and size composition of these landings are notably different from those reported in adjacent Oman, which also has targeted fisheries for large pelagic species (Henderson et al., 2007, 2009). These data also confirm regional differences in the reproductive biology of common fisheries species, as well as sex-based and sampling event-based differences in the landed size of some common species, which may be due to fisheries or biological factors. Together, these highlight the need for local characterizations of elasmobranch fisheries in the western Indian Ocean. This study further confirms that significant numbers of multiple species of elasmobranchs are landed in Kuwait and Qatar, although the FAO does not list any landings of elasmobranchs from these countries. Furthermore, Kuwait, Qatar and the U.A.E. routinely catch and land elasmobranchs and should therefore strive to develop a shark plan, although it should be noted that all other Gulf states (Bahrain, Iran, Iraq and Saudi Arabia) have some documentary evidence of elasmobranchs occurring in fisheries, particularly as by-catch (Moore, 2011). Given the multiple nations that surround The Gulf, a shark plan may be best achieved with a regional approach, as was done for the Mediterranean Sea (UNEP, 2003). TAXONOMY AND SPECIES RECORDS The current study has provided valuable information on the diversity of elasmobranchs in the north-western Indian Ocean, an area which is in general poorly sampled despite indications that its elasmobranch fauna has significant biogeographic and taxonomic interest (Moore, 2011). While 39 taxa were recorded, many of these occurred infrequently, and the commercial harvest was dominated by a small number of small-sized sharks. The surveys provided a number of new records, the most notable of which was the rediscovery of C. leiodon in Kuwait, previously known only from a single specimen collected over 100 years ago from 3000 km away in Yemen (Moore et al., 2011). The surveys also provided significant range extensions for a number of shark (Moore et al., 2010) and batoid species, including the first © 2012 The Authors Journal of Fish Biology © 2012 The Fisheries Society of the British Isles, Journal of Fish Biology 2012, doi:10.1111/j.1095-8649.2011.03210.x
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