KARACHI A female Risso's dolphin was found dead on the beach near Gunz area, Jiwani, by a team of researchers recently.
This is the first time that a dolphin of this species has washed ashore along the Pakistan coast.
In surveys done between 2005 and 2008, the Cetacean Conservation Pakistan (CCP) team has confirmed the presence of 12 different species of cetaceans (whales, dolphins and porpoises) along the country's coastline. Risso's dolphins were seen both along the Sindh and Balochistan coastlines during these surveys.
This is the first dolphin, however, to have died and have its body wash ashore in Pakistan. The body was spotted by Umer Waqas and Sabir Ali, both working with the CCP.
Speaking to Dawn, Mohammad Shoaib Kiani, a PhD student at the Centre of Excellence in Marine Biology, Karachi University, and member of the team, said the cause of death was still unclear. A few samples have been sent, however, for DNA and toxicological testing to a lab on the KU campus.
“It had no marks of any injuries. We are speculating that it may have washed ashore alive in the night and later died on the beach in the absence of any rescue efforts. Natural death is another possibility,” he said.
Expounding on the typical characteristics of a Risso's dolphin, he said that the animals were typically 10ft long (but can grow to up to 12ft) and could weigh up to 300-500kg. As with most other dolphin species, males are typically larger than females.
He said that more and more marine mammals were being stranded on the Pakistan coastline in recent years, but that no single factor was responsible for this. “I have a record of 125 strandings of marine mammals, most of them dolphins, in recent years. Of them, over 50 cases were recorded in the last three to four years, largely along Sindh's coast. This is because our team is more focused in that area and one can't rule out the possibility of more incidents of strandings in remote areas of Balochistan.”
Significant factors responsible for strandings, according to Kiani, included being caught as a 'by-catch', the activities of foreign trawlers, growing pollution, ship/boat strikes and, at times, naval exercises that make use of sonar equipment. Deliberate hunting and habitat loss were some threats that had endangered the mammal's survival all over the world, he said.
The 2005-08 surveys showed the presence of bottlenose dolphins, humpback dolphins, spinner dolphins, Risso's dolphins, killer whales (which are scientifically categorised as dolphins), finless porpoises, Bryde's whales, Cuvier's beaked whales, fin whales, sperm whales and hump-backed whales in Pakistan's waters. The largest of all mammals, the blue whale, has also been spotted.
The two-year research project on coastal marine cetaceans is a collaborative venture of three organisations Indus for All Programme (IFAP), Marine Conservation International (a UK-based organisation) and Pakistan Wetlands Programme (PWP). Dr Mauvis Gore from MCI is supervising this project.
Though the project focuses on two threatened Indus delta cetacean species, the Indo-Pacific humpback dolphin and Indo-Pacific bottlenose dolphin, information on all the cetacean species in the selected areas will be collected.