FEATURE CREATURE
FEATURE CREATURE HALAVI GUITARFISH GLAUCOSTEGUS HALAVI (
)
FEATURE IUCN RED LIST 2017 PHOTOGRAPHY PHILIPPE LECOMTE
RED LIST CATEGORY & CRITERIA: VULNERABLE Scientific Name: Glaucostegus halavi (Forsskål, 1775) Common Name: Halavi Guitarfish Synonym(s): Raja halavi (Forsskål 1775), Rhinobatos halavi (Forsskål, 1775), Scobatus halavi (Forsskål, 1775) Justification: The Halavi Guitarfish (Glaucostegus halavi) occurs in shallow waters of the Red Sea, Gulf of Aden, Sea of Oman, the Arabian Gulf and Arabian Sea to Pakistan and northern India (Gujarat). It is likely to grow slowly and mature late, giving it a low productivity. It is taken in variable quantities in gillnet and trawl fisheries, and habitat modification is a significant threat, particularly in the Gulf. There is preliminary evidence for declines of over 50% in the southern Gulf, and it would certainly have been impacted where heavy trawling pressure occurs off Gujarat (India) and probably elsewhere. Ongoing high levels of fishing pressure and coastal development are of concern, and overall it is suspected that the population would have declined by >30% over the last three generations (33 years). A further population
reduction is suspected over the next three generation lengths (2017-2050) based on current levels of exploitation, and the species is assessed as Vulnerable A2d+3d. Range Description: The Halavi Guitarfish is endemic to the Arabian Seas region, occurring in coastal waters of the Red Sea, Gulf of Aden, the Arabian Sea from Yemen to northern India (Gujarat) and the Gulf. Countries Occurrence: Native: Bahrain; Djibouti; Egypt; Eritrea; India (Gujarat); Iran, Islamic Republic of; Oman; Pakistan; Qatar; Saudi Arabia; Sudan; United Arab Emirates;Yemen FAO Marine Fishing Areas: Native: Indian Ocean – western Additional data: • Continuing decline in area of occupancy (AOO): Unknown • Extreme fluctuations in area of occupancy (AOO): Unknown • Estimated extent of occurrence (EOO) – km2 • Continuing decline in extent of occurrence (EOO): Unknown
• Extreme fluctuations in extent of occurrence (EOO): Unknown • Continuing decline in number of locations: Unknown • Extreme fluctuations in the number of locations: Unknown • Lower depth limit (metres): 100 Population: Frequent misidentification in the past may have complicated inferences of relative population size of this species. A recent study has recorded landings in the UAE where it is the most commonly landed guitarfish (14.7% of rhinopristoids) (R.W. Jabado unpub. data). It is uncommonly landed in Bahrain (Moore and Peirce 2013) and in the Saudi Red Sea (Spaet and Berumen 2015). However, landings are common in the Sudanese Red Sea (I. Elhassan pers. comm. 07/02/2017) and it has been recorded from fishery landings in Oman (Henderson et al. 2007). In Pakistan, it is frequently caught, but is not abundant (M. Khan pers. comm. 07/02/2017). Landings surveys in the UAE in recent years have demonstrated a rapid decline despite ongoing fishing effort; 10-20 individuals were regularly observed during 2010-2012, DECEMBER 2017 | DIVERS FOR THE ENVIRONMENT
27