nets due to their inability to detect the nets before collision. In 2001, 80 harbour porpoises were killed in salmon gillnet fisheries in British Columbia, Canada. Hector's and Maui's dolphins In New Zealand, these dolphins have a high rate of entanglement. Hector's dolphin (Cephalorhynchus hectori) is endemic to the coastal waters New Zealand and there are about 7,400 in abundance. A small population of Hector’s dolphins is isolated on the west coast of the island and have been declared a subspecies called Maui's dolphin. Maui's dolphins (Cephalofhynchus hectori maui) are often caught in set nets and pair trawlers resulting in less than 100 left in the wild. For protection, a section of the dolphin’s range on the west coast has been closed to gillnet fisheries. Indo-Pacific humpback and bottlenose dolphins Drift and bottom-set gillnets are the biggest conservation threat to these dolphins in the Indian Ocean. There have only been assessments in some areas, such as Zanzibar. Hunting, until 1996, reduced the population and contributed to its decline. Now hunting has been replaced with eco-tourism. It was estimated in 2001 that there are 161 bottlenose dolphins (Tursiops aduncus) and 71 Indo-Pacific humpback dolphin (Sousa chinensis) that are left based on photo-identification mark-recapture techniques. A study on bycatch revealed over 160 incidences of bycatch since 2000. Approximately 30% of bycatch is in drift and bottom-set gillnets. Mortality is about 8% and 5.6% for bottlenose and humpback dolphins respectively . The mitigation of bycatch is imperative for these species and eco-tourism. Irrawaddy dolphins Based on a survey in 2001, fewer than 70 Irrawaddy dolphins (Orcaella brevirostris) left in the upper region of the Malampaya Sound in the Philippines and 69 individuals in the Mekong River. They have been severely impacted by lift nets, and crab gear and they are critically endangered. It is estimated that mortality from bycatch may be greater than 4.5% in Malampaya Sound and 5.8% in the Mekong River. The population is declining dramatically. Current bycatch levels are unsustainable and bycatch reduction measures as well as long-term systematic monitoring are urgently required. The elimination of gillnets from areas of high use is needed and economic incentives need to be provided to the local people. Spinner and Fraser’s dolphins In the Philippines, tuna driftnet fisheries have a substantial impact on the populations. One tuna fishery alone kills 400 spinner dolphin (Stenella longirostris) and Fraser's dolphins (Lagenodelphis hosei) each year. Round-haul