![]() ![]() In addition, the populations of each of the five countries in which black rhinoceroses still persist are mostly the result of large scale consolidation of fragmented local populations by means of past translocations and it is unknown how these admixed stocks relate to their founding local populations. One reason for the absence of a geographic overview of historic population ranges is that local extinctions, especially those occurring earlier in the 20 th century (mainly in West, Central and North-East Africa), may have occurred even before populations were identified by the relevant conservation authorities. However, the geographic and taxonomic patterns used to underpin this scheme coincide with gaps in specimen data, which need to be filled to better define population limits 15.ĭuring the 20 th century, most black rhinoceros populations were hunted to low numbers and many went extinct ( Fig. bicornis) subspecies was adopted by the IUCN’s African Rhino Specialist Group (AfRSG) and is the prevailing basis for conservation management of this species ( Fig. The four-subspecies classification of du Toit (1987) 11 dividing the species into the western ( D. bicornis is problematic because the evolutionary status of black rhinoceros populations has been debated for decades 8, 9, 10, 11, 12, 13, 14. The lack of a range-wide genetic assessment of D. Such information is now crucial to better understand ongoing trade and to monitor remaining populations 6, 7. However, in contrast, large-scale genetic management of black rhinoceros populations, including the assignment of individuals, their remains and products, to source populations, has been hampered by a lack of a range-wide understanding of the species’ genetic variation. Recently, molecular genetic approaches have been deployed in black rhinoceros conservation for forensic identification and enforcement purposes 5. Annual poaching counts have exceeded 1,000 individuals each year since 2013 4. Recently, it has been reported that rhinoceros poaching has reached a critical point, and if the killing continues, rhinoceros deaths would exceed births in 2016–2018 3. ![]() At the 16 th meeting of the Conference of Parties to the Convention on International Trade in Endangered Species (CITES 2013) 2, it was reported that poaching of black and white rhinoceroses in South Africa had increased from 13 per annum in 2007 to 455 by mid-October 2012, and Zimbabwe, where populations are much smaller, lost an average of 39 rhinoceroses per annum between 20 (CITES 2013) 2. Renewed poaching has threatened this recovery, as rhinoceros horn has attained an unprecedented and steadily rising value of $65,000 per kilogram 1. 1b), the black rhinoceros now survives in only five countries: South Africa, Namibia, Kenya, Zimbabwe and Tanzania (ranked by total population size). Despite a historic range that included much of sub-Saharan Africa ( Fig. During the 20 th century, populations are thought to have declined by more than twenty-fold until the mid-1990s, when intensive protection led to a population recovery to just over 5,000 individuals by 2014. longipes) declared extinct in 2011, has raised fears that this species will disappear from the wild within the next two decades 1 ( Fig. The well documented poaching and subsequent demographic collapse of black rhinoceros ( Diceros bicornis) populations, including the western subspecies ( D. Our results suggest a complete re-evaluation of current conservation management paradigms for the black rhinoceros. We also identify conservation units that will help maintain evolutionary potential. ![]() longipes), declared extinct in 2011, extends into southern Kenya, where a handful of individuals survive in the Masai Mara. We found that the historic range of the West African subspecies ( D. ![]() Genetically unique populations in countries such as Nigeria, Cameroon, Chad, Eritrea, Ethiopia, Somalia, Mozambique, Malawi and Angola no longer exist. Using both mitochondrial and nuclear datasets, we described a staggering loss of 69% of the species’ mitochondrial genetic variation, including the most ancestral lineages that are now absent from modern populations. Here we examined the range-wide genetic structure of historic and modern populations using the largest and most geographically representative sample of black rhinoceroses ever assembled. This knowledge gap has hampered conservation efforts because hunting has dramatically reduced the species’ once continuous distribution, leaving five surviving gene pools of unknown genetic affinity. Despite a wide historic distribution, the black rhinoceros was traditionally thought of as depauperate in genetic variation, and with very little known about its evolutionary history. The black rhinoceros is again on the verge of extinction due to unsustainable poaching in its native range. ![]()
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