Abstract

HADDAD, Charles R.  and  DIPPENAAR-SCHOEMAN, Anna S.. Diversity of non-acarine arachnids of the Ophathe Game Reserve, South Africa: Testing a rapid sampling protocol. Koedoe [online]. 2015, vol.57, n.1, pp.1-15. ISSN 2071-0771.  http://dx.doi.org/10.4102/koedoe.v57i1.1255.

As part of the second phase of the South African National Survey of Arachnida (SANSA), field surveys were conducted in many degree-square grids throughout the country using a standardised rapid sampling protocol. This study reports on the arachnid diversity of the Ophathe Game Reserve (OGR) in northern KwaZulu-Natal, as found during a preliminary survey in June 2007 (mid winter) and a SANSA field survey in October 2008 (mid spring) in four representative habitats. The SANSA survey included seven sampling methods: pitfalls, beating, sweep-netting, litter sifting, hand collecting, night collecting and Winkler traps. A total of 282 species in six arachnid orders were collected during the two surveys, of which spiders were the most species-rich order (268 species in 47 families). The SANSA survey yielded 966 adult arachnids, representing six orders and 197 species, with a further 67 species represented only by immatures. Although adult arachnid abundance (n) differed considerably between the four habitats (range: 156-321), adult species richness (S_obs) was less variable (range: 65-85). These survey results are comparable with several longer-term surveys in the Savanna biome, and indicate that the SANSA sampling protocol can yield an impressive diversity of arachnids during a relatively short period of sampling, with a high level of coverage (> 0.8 for sites and most sampling methods) and moderate levels of sample completion for adults (> 0.55 for all sites), despite logistical and temporal challenges. Additional repetitions of the SANSA sampling protocol in other seasons will likely increase biodiversity knowledge of arachnids in OGR considerably. CONSERVATION IMPLICATIONS: The implementation of rapid sampling protocols in an atlas project is essential to generate a large volume of species-level data. The SANSA protocol is an efficient means for rapidly generating arachnid data, and in future will allow for an assessment of diversity patterns in degree-square grids across South Africa.

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