Extinction of the Javan Rhinoceros from Vietnam
Twenty rhinoceros faecal samples collected by CTNP and WWF between 2003 and 2006 were sent to Queen’s University in April 2010 for analysis. Bacterial diversity profiles of these samples concluded that there were at least two individuals present in the population in 2003-2006.
WWF and Cat Tien National Park conducted a comprehensive survey of the Javan rhinoceros population from October 2009 to April 2010, to determine the population status through genetic analysis of rhinoceros dung samples collected. Dung detection dogs were employed for the survey to increase the detection of rhinoceros dung. The team achieved good coverage, surveying the 6,500ha ‘rhino core area’ three times and approximately 3,500ha of the wider area, where signs of rhino have not been recorded since 1993, to ensure no individuals were missed.
Twenty-two dung samples were collected by the survey team from the rhino core area between October 2009 and February 2010 and sent to Queen’s University, Canada for genetic analysis. No signs of rhinoceros were found outside of the rhino core area at any time during the survey. From 5th February to mid-April, the team did not find any new rhinoceros footprints or dung in Cat Loc.
On 29th April 2010 a Javan rhinoceros was found dead in Cat Loc; samples of skin and teeth were taken from the skeleton and sent to Queen’s University to be included in the genetic analyses. The genetic analyses confirmed that all of the dung samples collected in 2009/2010 belong to one individual, the same individual that was found dead in April 2010. Genetic sexing indicates that this individual was female.
Bacterial diversity profiles of the faecal samples, which discriminate among different individuals, supported the conclusions from the genetic work that there was 1individual in 2009-2010, and showed that this individual was one of the two individuals present in 2003-2006.
Given the good survey coverage of the area, the field observations, and the genetic and bacterial diversity work, we can therefore confirm that the Vietnamese population and the annamiticus subspecies of Javan rhinoceros is extinct. The Javan rhinoceros is therefore confined to one population on Java, Indonesia.
Poaching was identified as the cause of the extinction of the subspecies; the last individual was shot in the leg, which probably caused its death, and the horn had been removed (Streicher et al 2010). Habitat loss due to agricultural conversion and development is also recognised as a driving force behind the loss of this population; the habitat of the species in Vietnam has declined from 75,000ha when it was rediscovered in 1988, to less than 30,000ha today. Furthermore, the population was restricted to only 6500ha of this habitat due to the presence of a heavily used motorbike dirt-track connecting settlements within the park, which restricted access to other parts of Cat Loc, and encroachment of agricultural land within the rhino core
The issues of poaching and habitat loss are not unique to Cat Tien National Park but are a nationwide problem in Vietnam, as a result of poor protection and law enforcement efforts and ineffective protected area management. Consequently, Vietnam is on the verge of an extinction crisis with many other species threatened by hunting and habitat loss. Significant improvements need to be made in law enforcement and protected area management in Vietnam, and the way in which conservation organisations cooperate with protected areas, to ensure that other species do not share the same fate as the Javan rhinoceros.