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10 A. B. M. MOORE ET AL. exceptions: (1) two subtly different species of cownose rays Rhinoptera sp., for which field identification characters (Last et al., 2010b) only became available at the end of the survey, and (2) a number of morphologically similar Carcharhinus species in the initial part of the first survey (Kuwait in 2008). Undescribed taxa [whipray Himantura sp. B sensu Manjaji, 2004; guitarfish Rhinobatos cf. punctifer (‘RHY’ sensu Henderson et al., 2007)] were also recorded, as was a cryptic species complex [Himantura uarnak (Gmelin 1789)]. Preliminary examination of barcode data, photographs and specimens indicates that taxonomic clarification is also required for several more batoid species collected in this survey (White et al., 2010; R. D. Ward, W. White, P. Last, pers. comms.). TAXONOMIC COMPOSITION A total of 39 elasmobranch species (including the H. uarnak species complex) were recorded during the survey, comprising 21 shark, five guitarfish and 13 ray species (Table I). These belonged to a total of 13 families, of which the most species-rich were whaler sharks (Carcharhinidae, 14 species) and stingrays (Dasyatidae, five species). The vast majority (c. 80%) of elasmobranchs were sharks, with rays comprising c. 16%; guitarfishes were relatively unimportant overall (c. 4%). Amongst the sharks, carcharhinids dominated (c. 73% of total individuals), with weasel sharks (Hemigaleidae) and carpetsharks (Hemiscyllidae) comprising c. 3% each. Houndsharks (Triakidae) and hammerhead sharks (Sphyrnidae) each comprised
ELASMOBRANCHS IN KUWAIT, QATAR AND ABU DHABI 11 (a) (b) (c) (d) Fig. 2. Broad taxonomic composition of elasmobranchs recorded at each sampling event: (a) Kuwait 2008, (b) Qatar 2009, (c) Abu Dhabi 2010 and (d) Kuwait 2011. , Chiloscyllium arabicum; , Triakids & Hemigaleids; , small (100 cm maximum L T ) carcharhinids and sphyrnids; , guitarfishes; ,rays. further species was recorded beyond approximately three quarters (c. 1500) of the total individuals recorded, suggesting that these surveys adequately recorded species richness of landings at the time of the survey. Conversely, new taxa were recorded throughout the much smaller survey in Abu Dhabi, indicating that species richness was insufficiently sampled at this location. SIZE, MATURITY AND SEX COMPOSITION Table I presents details of species abundance, size ranges for males and females and male maturity for the individuals sampled in the 2008–2011 surveys. The vast majority (c. 90%) of all sharks recorded were small with an L T between 50 and 90 cm, and this pattern was broadly consistent across the four sampling events (Kuwait 2008 c. 85%; Qatar c. 94%; Abu Dhabi c. 87%; Kuwait 2011 c. 87%) (Fig. 2). The sample comprised mostly of species with a small reported maximum size of 200 cm L T [comprising pigeye Carcharhinus amboinensis (Müller & Henle 1839), spinner Carcharhinus © 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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