Japan dolphins and other sea species 'face extinction' The EIA says that dolphins are trapped and then sold to aquaria or slaughtered for consumption Japan's hunting of dolphins, smaller whales and porpoises is threatening some species with extinction in its coastal waters, a report by a British environmental group has said. The Environmental Investigation Agency (EIA) report says that more than a million such creatures have been killed in Japanese hunts in the past 70 years. It says that each year thousands are killed despite conservation concerns. The Japanese government has not commented on the report. But it has consistently defended its coastal whaling as a longstanding tradition, a source of livelihood and necessary for scientific research. The government has also argued that small cetaceans should be excluded from the International Convention on Whaling. 'Grave concerns' The BBC's Rupert Wingfield-Hayes in Tokyo says that the Japanese practice of driving many dolphins and porpoises onto beaches to be slaughtered has drawn international condemnation. Japanese hand-harpoon hunting vessel The EIA says that porpoises, dolphins and small whales are often chased until they become exhausted and within range of hand-held harpoons. The EIA says that it is also unsustainable, and a danger to human health. Studies have found high levels of mercury and industrial chemicals like PCBs in dolphin and porpoise meat. One study found people living in one dolphin-eating community in central Japan have mercury levels five times higher than normal.

There have been a few times in the history of mankind when we nearly died out as a species. Anthropologists call these events “bottlenecks”, times when the population of humans shrank – perhaps to as few as 2,000 people over 50,000 years ago. At those levels, we would be categorised as an endangered species on the IUCN Red List, existing in even fewer numbers than wild tigers do today. We survived, and in fact we’ve thrived, mainly because we adapted our environment to suit our needs. But to what degree has the survival and triumph of our species changed our planet? The best people to answer this could well be those who have the grandest perspective. Geologists can take a 4.5-billion-year step back and look at the human impact on our planet in the context of its long history – they can identify changes in the rock record within layers of deposited sediments that build up and are compressed over time.

Red List counts 'on the brink' species

East Asia's status as the world's main "extinction hotspot" is confirmed in the new Red List of Threatened Species.

Sawfish snout senses, swipes and stabs

The spectacular snouts of sawfish are

revealed as complete hunting weapons, sensing prey and killing them. The saws, which can grow more than a metre long in some species, have previously been identified as able to sense prey by their electric fields. Now, researchers have filmed the fish impaling prey on the teeth of the saws. They suggest in Current Biology that sawfish are more active hunters than previously thought, which could help in their much-needed conservation.

All seven species are listed as Critically Endangered on

South Africa troops tackle rhino poachers

Justice Minister Jeff Radebe said four military companies would be sent to the borders with Zimbabwe, Swaziland and Lesotho. Syndicates export the horns from Africa to parts of Asia and the Middle East. In 2011, a record 450 rhinos were killed by poachers in South Africa, the Department of Environment Affairs says. Mr Radebe said about 600 soldiers would join the fight against rhino poaching. "The deployment includes army engineers who are conducting repairs and maintenance on the Zimbabwe-Mozambique border fence, which is approximately 140 kilometres (85 miles)," Mr Radebe said. Last year troops were deployed along the Mozambican border, many of them inside the world-famous Kruger National Park where more than 200 rhinos were killed last year.