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SOUTH AFRICAN REPTILE SPECIES AND THEIR PHYLOGENETIC RICHNESS NOT SUFFICIENTLY SAFE-GUARDED.

Authors :
Tolley, Krystal A.
Weeber, Joshua
Maritz, Bryan
Verburgt, Luke
Bates, Michael F.
Conradie, Werner
Hofmeyr, Margaretha D.
Turner, Andrew A.
da Silva, Jessica M.
Šmíd, Jiří
Alexander, Graham J.
Source :
African Herp News; Dec2019, Issue 72, p91-92, 2p
Publication Year :
2019

Abstract

African reptiles are under threat primarily due to habitat loss as a result of agriculture, resource extraction, and urbanisation. Extinction risk of South African reptiles was assessed as of 2018 using IUCN criteria and we 'backcast' these assessments to infer extinction risk circa 1990. A Red List Index (RLI: a measure of the extinction risk for a group of species) for 1990 and 2018 was estimated, and the protection level afforded to South African reptiles was investigated by intersecting reptile distributions with the network of protected areas. Furthermore, phylogenetic diversity of South African reptiles was mapped and intersected with national land cover for 1990 and 2013 to identify areas of high phylogenetic richness that may be impacted by habitat transformation. Level of extinction risk for South African reptiles (ca. 5.4%) is lower than the global average, and most currently threatened species would have already been at risk by 1990. The RLI is slightly lower in 2018 than it was in 1990, and the decrease is more prominent for endemic reptiles than for all reptiles combined. Most South African reptiles fall into the Well Protected category, implying that the protected area network has substantial conservation impact. However, most threatened reptile species are Poorly Protected or Not Protected. The current extent of the protected area network therefore, does not adequately mitigate extinction risk for reptiles. Notably, two South African reptiles are Critically Endangered and in protected areas, two others are already classified as Extinct, and rough estimates of extinction rates are similar to values estimated for other vertebrates. Phylogenetic diversity mapping showed that the greatest historical impacts to phylogenetic richness for reptiles are in the northeast (Limpopo, Mpumalanga, and Gauteng provinces), southwest (Western Cape Province) and the coastal margin of KwaZulu-Natal. By considering additional metrics that are directly guided by our in-depth knowledge of the species, their distributions and the threats, we demonstrate that South African reptiles are under pressure, that risk of extinction is tangible for several species and that phylogenetic richness of reptiles in certain areas of South Africa is imperilled by loss of habitat. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
10176187
Issue :
72
Database :
Supplemental Index
Journal :
African Herp News
Publication Type :
Academic Journal
Accession number :
141538503