The following two papers on marine mammals in Iran were published last month.  Please email Gillbraulik@downstream.vg if you would like a pdf of either one.

Braulik, G. T., Savadkouhi, O. S., Fadakar, S., Mohammadi, H., Brownell Jr., R. L., Reeves, R. R., Nabavi, M. B. and Fernandez, A. 2010. A retrospective investigation of two dolphin mass mortality events in Iran, Autumn 2007. Zoology in the Middle East. 49:13-26.

During the autumn of 2007, two mass mortality events involving at least 152 small cetaceans were reported from southern Iran. Both events occurred on the Gulf of Oman coast near the town of Bandar Jask, and were separated by a month in time and more than 170 km in distance.

The first event, on 20 September 2007, involved 79 animals, probably all spinner dolphins (Stenella longirostris). Dead animals, all exhibiting a similar degree of decomposition, drifted to shore along 13 km of coastline over a period of approximately 24 hours. These circumstances suggest that the mortality was caused by a single acute event at sea.  Several carcasses had evidence of traumatic injuries, the stranding event was spatially and temporally coincident with an active fishing ground, and other potentially bycaught and discarded species were found on the beach.  This pattern is generally consistent with the hypothesis that the dolphin mortality was caused by fishing operations, although the available data are insufficient to confirm that hypothesis unequivocally.

On 24 October 2007 there was a mass stranding of 73 live striped dolphins (Stenella coeruleoalba).  The striped dolphin is a pelagic species believed to be rare in the Gulf of Oman.  The most likely explanation for this mass stranding is that the dolphin group was trapped by a falling tide among the complex sandbanks of the Kangan estuary. Striped dolphins are not normally found in shallow water or near shore, and their occurrence in this area is considered unusual. The factor or factors that caused them to enter this atypical habitat remain unknown.

The two mass mortality events involved different species and exhibited many different characteristics; there is no evidence to suggest that they were linked.  As the cetacean fauna of Iran is little known, it is hoped that the great national and international interest generated by these events will enhance Iran’s capacity and motivation for research and conservation of marine mammals. 

Braulik, G. T., Ranjbar, S., Owfi, F., Aminrad, T., Dakhteh, S. M. H., Kamrani, E. and Mohsenizadeh, F. 2010. Marine mammal records from Iran. Journal of Cetacean Research and Management. 11 (1):49-63.

Iran has 1,700km of coastline that borders the Persian Gulf and the Arabian Sea in the northwest Indian Ocean.  Apart from a handful of records, almost nothing is known about which marine mammal species occur in Iranian waters.  This review was conducted to fill this information gap.  A total of 127 marine mammal records of 14 species were compiled from Iranian coastal waters.  Ninety-nine were from the Persian Gulf, 26 from the Gulf of Oman and 2 were of unknown location.  Records of finless porpoise (Neophocaena phocaenoides) (25), Indo-Pacific humpback dolphin (Sousa chinensis) (24) and Indo-Pacific bottlenose dolphin (Tursiops aduncus) (22) were by far the most numerous, a probable reflection of their inshore distribution and local abundance. Other species recorded were long-beaked common dolphin (Delphinus capensis tropicalis), rough-toothed dolphin (Steno bredanensis), striped dolphin (Stenella coeruleoalba), spinner dolphin (Stenella longirostris), Risso’s dolphin (Grampus griseus), false killer whale (Pseudorca crassidens), sperm whale (Physeter macrocephalus) and dugong (Dugong dugon).  Records of 26 Mysticetes were compiled, 10 of which were tentatively identified as Bryde’s whales (Balaenoptera edeni), 1 possible fin whale (Balaenoptera physalus), 3 Humpback whales (Megaptera novaeangliae) and the remainder were not identified to species.  The largest threat to small cetaceans in Iran is likely to be incidental capture in fishing gear.  Nine finless porpoises were recorded as bycatch and this and other coastal species may be declining due to unsustainable mortality rates.  Some of the world’s busiest shipping lanes pass through Iranian waters and ship strikes are likely to be the largest threat to Mysticetes in the area.

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Gill Braulik

Sea Mammal Research Unit

Scottish Oceans Institute

University of St. Andrews

St. Andrews, Fife, UK

KY16 8LB

Mob: +44 7530900550

Research Fellow

Pakistan Wetlands Programme

House 3, Street 4,  Sector F7/2

Islamabad, Pakistan

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