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4 A. B. M. MOORE ET AL. E); in Qatar (12–29 April 2009) at Corniche, Doha (25 ◦ 17 ′ N; 51 ◦ 32 ′ E), Doha main wholesale market (25 ◦ 17 ′ N; 51 ◦ 32 ′ E) and Al Khor (25 ◦ 41 ′ N; 51 ◦ 31 ′ E); and in the U.A.E. (Abu Dhabi Emirate) (5–11 April 2010) at Abu Dhabi City (Mina Zayed) (24 ◦ 30 ′ N; 54 ◦ 22 ′ E) (Fig. 1). Elasmobranchs were openly sold in Kuwait in 2008, but in 2011, the Public Authority for Agriculture and Fisheries (PAAFR) was actively enforcing a ban on their sale in the market, so most sampling was performed at the quayside. Further brief SCS visits were made to Qatar (Doha wholesale market) in April of both 2010 and 2011, although these were not sampled and only photographs were taken for later evaluation of broad species composition. A planned SCS market survey to Bahrain in April 2011 was postponed as a result of political unrest. All specimens were identified and measured to the nearest cm using total length (L T , upper caudal fin lobe straightened along the body axis) for sharks and guitarfishes (i.e. Rhinidae, Rhinobatidae and Rhynchobatidae), or disk width (W D ) for rays (i.e. all non-guitarfish batoids). Sex was recorded and apart from a few instances [including eight pregnant whitecheek shark Carcharhinus dussumieri (Müller & Henle, 1839)], male and female elasmobranchs were not routinely dissected for macroscopic examination of the reproductive tract owing to logistical constraints. For male sharks, maturity was categorized based on a slightly adapted version of the scale in Henderson et al. (2006) but using only external examination of claspers. The classes used were juvenile (i.e. claspers undeveloped, not extending beyond posterior tips of pelvic fins), maturing (extending beyond posterior margin of pelvic fin, but flexible and not fully calcified) and mature (much longer than pelvic-fin rear margin, rigid). From this, a male maturity size range was derived for each species, from the size of the smallest maturing individual to the size above which all males were mature. These data were also used to construct maturity ogives and L T at 50% maturity (L T50 ). For rays, only the size above which all individuals were deemed mature (i.e. fully developed, rigid claspers) is presented here; male maturity data for guitarfishes are not presented as claspers can remain flexible in mature animals (A. Henderson, pers. comm.). DATA ANALYSIS For those species where a total of >100 individuals were recorded (seven sharks and three batoids) the size-frequency distributions for each sex were tested to see if data conformed to a normal distribution using an Anderson–Darling test. Dependent on whether data were distributed normally or not, intergender size differences were then investigated using either a two-tailed t-test or a Mann–Whitney U-test, to test for possible sex-based differences in fisheries landings. The Mann–Whitney U-test was further used to investigate possible geographic and temporal differences in landed size for both sexes between sampling events in the two most commonly recorded species, i.e. milk shark Rhizoprionodon acutus (Rüppell, 1837) and C. dussumieri. Size-frequency distributions of males and females were compared using a χ 2 contingency test with the size distribution divided up into 5 or 10 cm size class intervals as appropriate to the L T of the species under consideration. To test the null hypothesis of sex ratios being at parity for each sampling event, a χ 2 test was performed for each species. For male sharks with a sample size of >200, L T50 was calculated using the logistic equation Y = x + (z − x)(1 + e −K(L T−L T50 ) ) −1 ,whereY is the percentage of males mature in the L T size class (cm) and K, x and z are constants. The equation was fitted using the non-linear curve fitting programme in Minitab v14 (www.minitab.com). The relationships between C. dussumieri maternal L T and both litter size and mean embryo L T were investigated using correlation analysis. RESULTS IDENTIFICATION AND TAXONOMY A total of 4649 elasmobranchs were examined during the survey (Table I). The vast majority of individuals were successfully identified to species level, with two © 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 5 Table I. Elasmobranch taxa recorded in surveys of markets and harbours during April in Kuwait (2008 and 2011), Qatar (2009) and Abu Dhabi (2010): number, percentage of total of all species, size range by sex (sharks and guitarfishes LT, raysWD; mean ± S.D. cm) and male maturity. For sharks, the range of the smallest maturing size above which all males were mature, excluding anomalous outliers, and for rays, only the size above which all males were mature are presented Taxon Kuwait 2008 Number of individuals (% total of all species combined) Kuwait 2011 Qatar Abu Dhabi Total all sites Male (♂) and female (♀) size range (mean ± s.d. cm) Male maturity (cm) Sharks Hemiscyllidae Chiloscyllium arabicum 20 (1·32) Triakidae Mustelus mosis 15 (0·99) Hemigaleidae Chaenogaleus macrostoma 39 (2·57) Hemipristis elongata 1 (0·07) Paragaleus randalli 5 (0·33) Carcharhinidae Carcharhinus spp. A 62 (4·09) Carcharhinus amblyrhynchoides 5 (0·33) 105 (15·02) 12 (1·72) 17 (2·43) 5 (0·25) 2 (0·10) 30 (1·49) — 1 (0·05) 5 (0·72) 35 (1·73) — 2 (0·10) 3 (0·43) — 130 (2·80) 5 (1·20) 1 (0·24) 34 (0·73) 87 (1·87) — 2 (0·04) 23 (5·54) 68 (1·46) — 64 (1·38) — — 8 (0·17) ♂ 56–77 (68·6 ± 4·4) ♀ 56–80 (68·8 ± 4·9) ♂ 65–84 (72·3 ± 4·9) ♀ 63–83 (76·0 ± 5·0) ♂ 70–90 (78·1 ± 5·2) ♀ 58–92 (80·3 ± 7·8) ♂ NA ♀ 117–119 (118·0 ± 1·4) ♂ 61–81 (73·2 ± 4·5) ♀ 56–83·6 (70·3 ± 8·3) ♂ 67–130 (84·1 ± 19·4) ♀ 63–140 (86·4 ± 15·3) ♂ 80–88 (85·4 ± 4·8) ♀ 82–166 (100·0 ± 36·9) 62–68 NAmin –65 NAmin –70 NA 61–64 NA NA © 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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