Will current conservation responses save the Critically Endangered Sumatran rhinoceros Dicerorhinus sumatrensis?

Abstract

The Critically Endangered Sumatran rhinoceros Dicerorhinus sumatrensis formerly ranged across South-east Asia. Hunting and habitat loss have made it one of the rarest large mammals and the species faces extinction despite decades of conservation efforts. The number of individuals remaining is unknown as a consequence of inadequate methods and lack of funds for the intensive field work required to estimate the population size of this rare and solitary species. However, all information indicates that numbers are low and declining. A few individuals persist in Borneo, and three tiny populations remain on the Indonesian island of Sumatra and show evidence of breeding. Rhino Protection Units are deployed at all known breeding sites but poaching and a presumed low breeding rate remain major threats. Protected areas have been created for the rhinoceros and other in situ conservation efforts have increased but the species has continued to go locally extinct across its range. Conventional captive breeding has also proven difficult; from a total of 45 Sumatran rhinoceros taken from the wild since 1984 there were no captive births until 2001. Since then only two pairs have been actively bred in captivity, resulting in four births, three by the same pair at the Cincinnati Zoo and one at the Sumatran Rhino Sanctuary in Sumatra, with the sex ratio skewed towards males. To avoid extinction it will be necessary to implement intensive management zones, manage the metapopulation as a single unit, and develop advanced reproductive techniques as a matter of urgency. Intensive census efforts are ongoing in Bukit Barisan Selatan but elsewhere similar efforts remain at the planning stage.

Land Use and Landscape Pattern Changes on the Inside and Outside of Protected Areas in Urbanizing Selangor State, Peninsular Malaysia

“…Sungai Karang Forest Reserve and Raja Musa Forest Reserve) (Sasidhran et al 2016). Havmøller et al (2015) suggested that this species was already extinct in the wild in Peninsular Malaysia. Threats that responsible for the species' decline are habitat loss and poaching (Ahmad et al, 2013;Rabinowitz 1995).…”

Herd demography, sexual segregation and the effects of forest management on Bornean banteng Bos javanicus lowi in Sabah, Malaysian Borneo

“…Between 1973 and2010, 39.5% of forest in Sabah, Malaysian Borneo, was lost to selective logging, fire and conversion to oil palm and timber plantations (Gaveau et al 2014). Of this forest loss, 97% occurred in habitat suitable for the Bornean banteng Bos javanicus lowi (Gaveau et al 2014, likely the rarest mammal in Sabah now that the Sumatran rhinoceros Dicerorhinus sumatrensis has been declared extinct in the wild in Malaysia (Havmøller et al 2016).…”

Preventing Global Extinction of the Javan Rhino: Tsunami Risk and Future Conservation Direction

“…; Havmøller et al. ). Individual‐based monitoring is especially important, as it provides a richness of demographic information (Clutton‐Brock & Sheldon ) that can be critical in identifying effective conservation actions.…”

“…However, essential information (i.e., population size and distribution) required to understand the causes of population contractions and evaluate extinction risk is often unavailable (Jetz & Freckleton 2015). Our knowledge of even endangered charismatic megafauna (e.g., primates, carnivores, and rhinos) often lack detailed spatial information about where individuals occur or precise population estimates that are so important in directing effective conservation actions (Linkie et al 2010;Groves and Leslie Jr 2011;McClintock et al 2015;Schwitzer et al 2015;Havmøller et al 2016). Individual-based monitoring is especially important, as it provides a richness of demographic information (Clutton-Brock & Sheldon 2010) that can be critical in identifying effective conservation actions.…”