Hexanchus griseus (Bonnaterre, 1788)

Alkusairy, Hasan & Saad, Adib, 2018, Species Composition, Diversity and Length Frequency of By-Catch Sharks from the Syrian Coast, International Journal of Research Studies in Zoology 4 (1), pp. 11-21 : 15

Hexanchus griseus

TL ranged between 102 and 310 cm for males and between 85 and 345 cm for females. Common TL ranged from 155 to 230 cm for males and from 175 to 275 cm for females. This species was recorded in all months through the period of study. Females constituted 63.5% of species catches. Its caught appeared a significant difference between seasons (X 2 = 11.441, P = 0.010), peak of season landing was in autumn ( Fig. 2a ), a high proportion of juveniles was recorded in spring ( Fig. 3a ). [ 16] suggested that males and females of H. griseus maturing at 300 and 350 cm TL, respectively. In Mediterranean Sea. Consequently, about 97% of males and 100% of females were immature of catches ( Fig. 4a ).

Figures

Figure 2. Changes of caught specimens number per season; (a) H. griseus,(b); H. perlo, (c); C. plumbeus, (d); M. mustelus (e); G. melastomus, (f); S. blainvillei, (g); C. moluccensis, (h); C. granulosus

Figure 3. Size (TL) variations of abundant and common of by-catch sharks per season off Syria coast. Males (gray), females (white): (a); H. griseus,(b); H. perlo, (c); C. plumbeus, (d); M. mustelus (e); G. melastomus, (f); S. blainvillei, (g); C. granulosus, (h); C. uyato

Figure 4. Total length (TL) frequency distributions (percent of species catch) of the abundant and common bycatch sharks off Syrian coast. Males (black), females (white). Vertical lines indicate maturity size of males (sporadic) and females (continuous) following literature: (a); H. griseus,(b); H. perlo, (c); C. plumbeus, (d); M. mustelus (e); G. melastomus, (f); S. blainvillei, (g); C. granulosus, (h); C. uyato