The hawksbill turtle is seriously threatened with extinction, due mainly to trade in tortoiseshell. This has sent the price rocketing. Divers hunting for lobsters and snappers find it rewarding to search even the remotest reefs in the hope of getting the odd turtle – worth $200 or more. The authors urge that only by stopping the trade through CITES can the hawksbill be saved.

Uganda's national parks are littered with elephant carcasses, poachers' camps and meat-drying racks, and poachers are better armed and equipped than the guards. And the slaughter continues. Dr Edroma, who is Director of the Uganda Institute of Ecology, lists the steps that must be taken if the present disastrous situation is not to deteriorate to the point where Uganda's wildlife is effectively exterminated.

Man depends on plants for his food – directly through crops and indirectly through animals – and all our staple foods are derived from only about 30 species of plants. Yet we continue to fell the forests and clear land, exterminating plants that could possibly avert disasters in the future – just as the apparently useless wild wheat discovered in Turkey in 1948 proved to be resistant to certain diseases, including four races of rust, and is now used to breed rust-resistant hydrids. The author lists some of the disasters now occurring, such as siltation of waterways resulting from erosion due to forest destruction – some bulk cargoes are now diverted round Cape Horn due to silt in the Panama Canal. He asks, how severe must ecological disasters become before we recognise our dependence? Dr Jarvis works for IUCN's Threatened Plants Committee (TPC) at the Royal Botanic Gardens, Kew.

With a wild population of only thirteen known birds, the California condor is close to extinction. In 1980 only two pairs even attempted to breed. Breeding in captivity seems the only hope of saving the species, but the project approved by the Federal Government has roused considerable controversy. The author, who spent two years in California, presents the arguments on both sides, outlines the reasons why he believes the experiment should be tried and assesses its chances of success. On June 30, however, after this article was written, a two-month-old California condor chick died while being handled. In a postscript to the article Stephen Mills comments on the effects of this death on the programme.

Paraguay still has a vast area of almost undisturbed forest and savanna in the region known as the Chaco, where three large national parks, totalling over 1½ million hectares, protect a fauna that includes jaguar, puma, ocelot and a peccary that was ‘rediscovered’ in 1975. In 1979 the author, who is widely known as a scientist and conservationist, spent two months in Paraguay investigating the wildlife situation and national parks and has made recommendations for conservation measures to the Government.

To reach the Manu National Park means a day's journey by road over the Andes from Cusco, climbing up to the high puna grassland where one enters the park at the Tres Cruces guard post, 3300m above sea level. The last part of the road down to Shintuya at 300m has four unbridged river crossings that are impassable in the wet season from November to March. At Shintuya, if no park boat is available, the onward journey to Pakitsa, the administrative headquarters where there is accommodation, can only be made by hiring the Dominican Mission boat at $100 a day plus 30 gallons of gasoline (if you can get it) as well as enough for the return journey from Pakitsa to Cashu Cocha.

In 1976 one of the authors saw a pet turtle which he recognised to be Phrynops hogei. This was remarkable because hitherto the type specimen, first described in 1967, was the only one known to scientists. However, since 1976 three other live animals have been seen, and also eight museum specimens. From the new information the authors conclude that the range of the species is small, and also that the type locality was wrongly given. They think the turtle may well be endangered, and suggest a captive breeding programme for its conservation.

In the early 1970s the huge lechwe herds gave the Kafue Flats in Zambia one of the highest carrying capacities in the world – an estimated 11,000kg per sq km. But these highly specialised antelopes depend on the annual floods of the Kafue river, to which particularly they have adapted their breeding behaviour and the leks in which they mate. Since the completion of two huge dams on the Kafue these floods are now controlled in the interests of making electricity, and not of the lechwe. The author, who studied the lechwe's social organisation and behaviour in the Lochinvar National Park, first describes the lechwe's remarkable lek system, how they are adapted to the floods to the point of being able to graze in water up to their shoulders, and the remarkable way in which they maximise the resources of the Flats. In the second part (page 481) he shows how the new flood control can disrupt their breeding behaviour and social organisation, which might lead to the extinction of the Kafue lechwe.

The Tanzania-Zambia railway now bisects the Magombera Forest Reserve in Tanzania, and as a result the most viable surviving population of the rare endemic Iringa red colobus is seriously threatened. The railway has facilitated tree-felling, settlement and cultivation, and the colobus habitat is already seriously damaged. The authors conducted a survey of the forest in 1979, and recommended that the southern part, which has a viable colobus population, be included in the neighbouring Selous Game Reserve, thus giving that part the stronger protection of a game reserve, and that the local people be compensated by the release to them of a small area of the Selous.

Russian settlement of the Far East inevitably reduced numbers of Siberian tigers and leopards, whose magnificent skins were a major lure for the settlers. But in the 1880s tigers were numerous, and tracks often seen in the streets of Vladivostok; many were shot. Today there may be 200 or so, which is probably as many as at any time since 1914. Now fully protected, they appear to have adjusted to the timber mills and the secondary forest, and are often seen on roads and near gardens. Their main strongholds are two reserves, both likely to be enlarged. The leopard, however, is seriously endangered, and depends for survival on two reserves in the Ussuri region which are being combined to create one huge reserve 200 miles long.