Troubled waters: Threats and extinction risk of the sharks, rays and chimaeras of the Arabian Sea and adjacent waters

The extinction risk of sharks, rays and chimaeras is higher than that for most other
vertebrates due to low intrinsic population growth rates of many species and the fishing intensity they face. The Arabian Sea and adjacent waters border some of the

most important chondrichthyan fishing and trading nations globally, yet there has
been no previous attempt to assess the conservation status of species occurring here.
Using IUCN Red List of Threatened Species Categories and Criteria and their guidelines
for application at the regional level, we present the first assessment of extinction
risk for 153 species of sharks, rays and chimaeras. Results indicate that this
region, home to 15% of described chondrichthyans including 30 endemic species, has
some of the most threatened chondrichthyan populations in the world. Seventy-eight
species (50.9%) were assessed as threatened (Critically Endangered, Endangered or
Vulnerable), and 27 species (17.6%) as Near Threatened. Twenty-nine
species (19%)
were Data Deficient with insufficient information to assess their status.
Chondrichthyan populations have significantly declined due to largely uncontrolled
and unregulated fisheries combined with habitat degradation. Further, there is limited
political will and national and regional capacities to assess, manage, conserve or rebuild
stocks. Outside the few deepsea locations that are lightly exploited, the prognosis
for the recovery of most species is poor in the near-absence
of management.
Concerted national and regional management measures are urgently needed to ensure
extinctions are avoided, the sustainability of more productive species is secured,
and to avoid the continued thinning of the regional food security portfolio.