Whale Distribution in the Northern Arabian Sea along Coast of Pakistan in 2019 based on the information obtained through Fisheries Crew-Based Observer Programme
Muhammad Moazzam, Rab Nawaz, Babar Khan, Sudheer Ahmed
International Whaling Commission
In 2012 WWF-Pakistan initiated an observer programme to monitor tuna gillnet operations in the coastal and offshore waters of Pakistan. Among other things, these observers were assigned to report observations of whales encountered during fishing operations. These vessels (with onboard observers) provided a platform of opportunity for recording the spatial and temporal distribution of whales in the Northern Arabian Sea. During 2019 a total of 7 sightings of Arabian Sea humpback whales, 1 sighting each of blue whales and Bryde???s whales, 6 sightings of sperm whales,8 sightings of baleen whales (that could not be identified to species level due to lack of adequate photographic or video evidence) and 3 records of entanglement and mortality of Cuvier???s beaked whales..
Fewer whales were recorded through the programme in 2019 than 2018 and 2017 when a total of 35 and 95 sightings of whale were recorded respectively. This decrease in sightings is attributed to many factors, including early closure of the fishing season in early April 2019 because of low catches and unreliable prices of tuna in the market. As such the fishery was closed for four months from mid-April to mid-August instead of the usual two months of June and July.
Extremely high sea surface temperatures during September to October 2019 (possibly an oceanic heat wave) were believed to be the cause of reduced tuna catches. Therefore, only a few tuna boats remained operational during this period. An unprecedented jellyfish bloom of Crambionella orsini from September 2019 onward forced fishermen to stop fishing operations during this period. Furthermore, the observer programme was completed on September, 2019, after which only 45 out of 75 observers voluntarily continued to provide information about sightings. The paper also reports on two baleen whale strandings - a Bryde???s whale (Balaenoptera brydei) stranded on the rocky shore at Gunz, western coast of Pakistan and a blue whale in Pushukan, Gwadar (West Bay).