Radio-collaring is widely used as a monitoring tool in the conservation of the black rhinoceros Diceros bicornis. We examined rates and causes of radio-transmitter collar failure on black rhino in the Sinamatella Intensive Protection Zone (IPZ), Zimbabwe, between September 1993 and February 2000. Two collar designs, hose and strap, were fitted on immobilized rhinos in four main collaring operations. Eighty nine collars were monitored: 28 hose and 61 strap. Within 12 months of placement, all hose collars had failed. Of the strap collars, 73 per cent of those on males and 44 per cent on females had failed within 12 months. Failure rates were significantly higher in males for both collar types. For strap collars older males had higher failure rates than younger males. There was some evidence of a higher failure rate of strap collars during the wet season. Thirteen per cent of strap and 4 per cent of hose collars were removed because of poor transmission; 15 per cent of strap collars were removed because of injury. The implications of collar failure rates and the use of radio-collaring as a routine protection and /or monitoring strategy are discussed.

Mountain gazelles were reintroduced to central Arabia during 1991–95. Hawtah reserve was searched for gazelles during the 1998–99 winter. Gazelles were seen in one wadi system and their signs were found in several others and on the plateau. Sightings were used to calculate the minimum number of gazelles in the Matham wadi system, which previously held most of the population. During October–November 1998, the minimum number was 64 per cent less than 4 years earlier. Frequent observation of recent signs in areas where no gazelles were seen suggested that daytime sightings alone were no longer adequate for monitoring this population. The decline in the number of gazelles seen, an increase in their flight distance and an apparent change in their activity patterns were consistent with the rangers' claim that poaching had commonly occurred. Poaching started after reserve management built, without adequate consultation, a new fence that was intended to bar local people from part of the reserve. Management lessons include the need for the following: continued monitoring of reintroduced populations after the initial postrelease phase; long-term dialogue with local people; effective law enforcement; and the management of aridland domestic livestock in ways that prevent inter specific competition for food causing the elimination of wild ungulates.

The Leuser Ecosystem, northern Sumatra, Indonesia, contains the world's largest orang-utan Pongo pygmaeus population. We examine the consequences of the recent wave of forest conversion, and legal and illegal logging, on orang-utan numbers in the Leuser Ecosystem. We review density variation inside the Leuser Ecosystem and its causes, and the consequences of selective logging, exhaustive logging and clear-felling for habitat conversion on orang-utan densities. The analysis of the orang-utan's decline is based on information on forest loss, logging intensity, and the delineation of logging concessions and legal changes in land use status. The results indicate a very rapid decline, by c. 45 per cent, from c.. 12,000 in early 1993, over a 6- to 7-year period. During 1998 and 1999, losses occurred at a rate of about 1000 orang-utans per year. At this rate, further losses in the near future are expected to put the survival of Leuser's orang-utans in serious doubt.

Proponents of community conservation present it as a means of reconciling conservation and development objectives by ensuring that the interests of local people are taken into account in making trade-offs. Conservation critics see it as a challenge to the state-led, scientific management that is necessary to guarantee the preservation of biodiversity. In this paper, we argue that community conservation is not one thing but many. It is evolving both as a concept and as a practice that must be built on. It is not a project or policy ‘choice’ that can be simply accepted or rejected. The key questions about community conservation are who should set the objectives for conservation policy on the ground and how should trade-offs between the diverse objectives of different interests be negotiated.

Abstract The Critically Endangered Antiguan racer Alsophis antiguae is confined to Great Bird Island, a 9.9 ha (24.5-acre) islet off the north-east coast of Antigua in the Lesser Antilles. This island represents well under 0.1 per cent of the species's historical distribution range. During the past 5 years, the total number of racers aged 1 year or more has fluctuated between 51 and 114, and currently stands at approximately 80. Since 1995, the Antiguan Racer Conservation Project (ARCP) has en-deavoured to save this harmless snake from extinction by using a combination of education, conservation breeding, habitat restoration, local capacity building and applied research. The Antiguan racer's ecology and population dynamics have become well understood after 5 years of intensive study, and the species has evidently benefited from the project's rat eradication programme. The snakes are still seriously threatened by other intrinsic and extrinsic factors, however, including inbreeding depression, frequent hurricanes, invasive predators and deliberate killing by tourists, as well as the problem that Great Bird Island is too small to support more than about 100 individuals. This paper describes the activities and impact of this project to date, and outlines a series of conservation activities to safeguard the long-term future of the species, which include reintroduction of the Antiguan racer to restored islands within its former distribution range.

The Sumatran orang-utan is in dramatic decline, including the population in its main stronghold, the Leuser Ecosystem, in Sumatra, Indonesia (C. P. van Schaik et al. (2001) Oryx 35, 14–25). The major threats to the survival of Sumatran orang-utans are identified as habitat loss (mainly from conversion to oil palm plantations), habitat degradation and habitat fragmentation. The immediate causes of this are identified as weak compliance with regulations and laws; weak law enforcement and the weak legal environment. Corruption is identified as the ultimate causal factor underlying these three immediate causal factors, along with a frontier mentality and bureaucratic constraints. Together, they have resulted in the destruction of prime orang-utan habitat. Several political actions are recommended to improve the effectiveness of habitat conservation for the orang-utan and several technical challenges are to be overcome once the policy context is right. The most crucial problem to solve is the lack of regular funds for enforcement operations and establishing a new system of enforcement that is effective. In addition, the Gunung Leuser National Park needs to be redesigned by enlarging it to cover all high biodiversity areas within the Leuser Ecosystem. Moreover, habitat corridors between important forest tracts need to be re-established.