KARACHI: Fishermen of Sindh and Makran coast, Balochistan, have witnessed occurrence of huge aggregations of oceanic squid in the offshore waters of Pakistan, claimed World Wildlife Fund for Nature-WWF Pakistan on Sunday.
Since November 2016, they have been sighting increase in the occurrence of oceanic (Sthenoteuthis oualaniensis), sometimes caught in their gillnets. In the beginning of this year, they located unprecedented concentration of this squid in offshore waters between 20o and 24o N both along Sindh and Balochistan coasts especially in the Khori Great Bank along Sindh coast and in off Malan along Balochistan coast.
This squid lives in open waters from the surface down to depths of around 1,000 m of ocean. It exhibits diurnal vertical migration and moves from deeper layers to surface or shallower waters during night. Japanese Research Vessel "R/V Shoyo Maru" during the survey in 1975 located dense concentration of this squid about 90 nautical miles off Pasni, Balochistan. They observed that purple back flying squid seemed to inhabit the 120-200 m depth layers during daytime. A positive light attraction effect due to the vessels light was observed during night time. Acoustic survey revealed that the squids are widely and abundantly distributed in the offshore waters in the region. However, in 1976 this research vessel again conducted acoustic surveys but could not locate any such concentrations.
Purple back flying squid is occasionally caught by fishermen as by-catch of trawling and tuna gillnetting in the offshore waters but never observed its dense concentration. A number of fishermen trained by WWF-Pakistan have reported unusual increase in the population of this species from November, 2016 to January, 2017. Interestingly, one of the fishermen, Nakhuda Hidayatullah, recorded a large number of squids encircling his gillnetter during the daytime (about 12:00 in the noon) at 65 nautical miles southwest of Cape Monz. This is quite extraordinary as purple back flying squids are seldom seen in the surface waters.
It is also interesting that in some other areas of Arabian Sea and Persian Gulf unprecedented occurrence of purple back flying squid was observed during November and December, 2016. Fishermen in Fujairah, UAE caught a large number of this oceanic squid in November, 2016. Similarly, very high catches of this species were recorded from Oman. From both these areas these squids were processed and exported. However, processing industry in Pakistan has not yet taken any such step for harvesting, processing and export of this squid.
Muhammad Moazzam Khan, Technical Advisor (Marine Fisheries) WWF-Pakistan pointed out that abundant occurrence of purple back flying squid in the Arabian can be attributed to long term changes in oceanic regime. Climate change may have also influenced the unprecedented appearance of the oceanic squids in Pakistani waters. As this species is found in abundance, therefore, there is an opportunity for the Pakistan's fisheries industry to gear up for exporting this high priced commodity to Far East Asian countries.
Commenting on the sudden increase in the purple back squid in Pakistan, Rab Nawaz, Senior Director Programmes, WWF-Pakistan stressed the need for studying long-term changes in the oceanographic factors that may result in increase of certain species. Occurrence of bloom of jellyfish in December, 2016 and that of purple back flying squid indicates that climate change is playing important role in the ecosystem dynamic of the Arabian Sea.