Species diversity and distribution pattern of marine mammals of the Persian Gulf and Gulf of Oman - Iranian Waters

A total of 98 marine mammal records from Iranian coastal waters of the Persian Gulf and Gulf of Oman were compiled of which 66 are previously unpublished new records. Seventy-nine were from the Persian Gulf and 16 from the Gulf of Oman coast. The largest numbers of records were from Qeshm Island and Bushehr Provinces. Records of finless porpoise (Neophocaena phocaenoides), Indo-Pacific humpback dolphin (Sousa chinensis) and Indo-Pacific bottlenose dolphin (Tursiops aduncus) were by far the most numerous probably reflecting their inshore distribution and local abundance. Other species recorded are common dolphin (Delphinus capensis tropicalis), rough-toothed dolphin (Steno bredanensis), Risso’s dolphin (Grampus griseus), false killer whale (Pseudorca crassidens), and dugong (Dugong dugon). Evidence of 22 Mysticetes were obtained eight of which were tentatively identified as Bryde’s whales (Balaenoptera edeni), three as fin whales (Balaenoptera physalus) and three as humpback whales (Megaptera novaeangliae). The largest threat to marine mammals in Iran is likely to be incidental capture in fishing gear. Six by-caught finless porpoises were recorded, and this species may be particularly vulnerable to incidental mortality in gillnets. Recommended marine mammal research, conservation and management small projects in Iran are described

Habitat fragmentation and species extirpation in freshwater ecosystems; causes of range decline of the indus river dolphin (Platanista gangetica minor)

World Wildlife Fund-Pakistan -(http://www.wwfpak.org/) funded the interview surveys with support through the Pakistan Wetlands Project. The US Marine Mammal Commission (www.mmc.gov) provided funding to GB for reporting and analysis in grant number E4047595.Habitat fragmentation of freshwater ecosystems is increasing rapidly, however the understanding of extinction debt and species decline in riverine habitat fragments lags behind that in other ecosystems. The mighty rivers that drain the Himalaya - the Ganges, Brahmaputra, Indus, Mekong and Yangtze - are amongst the world's most biodiverse freshwater ecosystems. Many hundreds of dams have been constructed, are under construction, or are planned on these rivers and large hydrological changes and losses of biodiversity have occurred and are expected to continue. This study examines the causes of range decline of the Indus dolphin, which inhabits one of the world's most modified rivers, to demonstrate how we may expect other vertebrate populations to respond as planned dams and water developments come into operation. The historical range of the Indus dolphin has been fragmented into 17 river sections by diversion dams; dolphin sighting and interview surveys show that river dolphins have been extirpated from ten river sections, they persist in 6, and are of unknown status in one section. Seven potential factors influencing the temporal and spatial pattern of decline were considered in three regression model sets. Low dry-season river discharge, due to water abstraction at irrigation barrages, was the principal factor that explained the dolphin's range decline, influencing 1) the spatial pattern of persistence, 2) the temporal pattern of subpopulation extirpation, and 3) the speed of extirpation after habitat fragmentation. Dolphins were more likely to persist in the core of the former range because water diversions are concentrated near the range periphery. Habitat fragmentation and degradation of the habitat were inextricably intertwined and in combination caused the catastrophic decline of the Indus dolphin.Publisher PDFPeer reviewe