Assessment of sampling approaches for a multi-taxa invertebrate survey in a South African savanna-mosaic ecosystem

Undergraduate entomology field excursions are a valuable source of biodiversity data: a case for spider (Araneae) bycatches in ecological studies

As part of an undergraduate Entomology module, field excursions were undertaken to a mixed livestock farm in central South Africa, during March-April 2015, 2016 and 2018-2020. The aim was for groups to determine and compare terrestrial arthropod biodiversity in three strata of three contrasting biotopes, with particular emphasis on insects. To determine the contributions such excursions make to documenting biodiversity of a non-target taxon, the spider (Arachnida: Araneae) data generated by students was compared with the local species richness (LSR) for the area. The LSR for the farm Bankfontein included a total of 242 species, representing 40 families. Over the 5 years, student groups sampled a total of 158 spider species, representing 65.3% of the LSR. The number of species sampled per year ranged between 57 and 94 for undergraduate students (1-3 groups), and was 119 species for the final year of the study carried out by the author and two post-graduate students (2 groups), which could be attributed to collector experience and modification of the sorting process for beat sampling, particularly. This study emphasizes the importance of utilizing students as a valuable resource to generate biodiversity data, particularly where financial and human resources may be limited.

A conservation assessment of the terrestrial invertebrate fauna of Mkambati Nature Reserve in the Pondoland Centre of Endemism

Mkambati Nature Reserve (NR) falls within the Pondoland Centre of Endemism, which is part of the Maputaland-Pondoland-Albany global biodiversity hotspot. The biodiversity status of this area is based largely on its flora, and the invertebrates are poorly known. The area is under threat from various proposed developments. We surveyed 14 orders in three invertebrate phyla at 26 sites with two main objectives: (1) to assess the fauna in terms of conservation value, and, (2) to identify habitats and sites of conservation concern. From the survey, 3231 samples were sent for identification and 425 species were identified. A minimum of 18 new species were confirmed. Mkambati NR shows exceptional diversity for molluscs (Gastropoda, 51 species), bees (Apoidea, 48 species) and true bugs (Heteroptera, 65 species). At least 43 species collected from the Reserve are South African endemics, 31 have a restricted distribution within South Africa and 18 are only known from the Reserve itself.Conservation implications: The authors provide the first assessment of the invertebrate fauna of the Mkambati NR, which indicates that it is a rich and important fauna. The results highlight the need to consider invertebrates in other biodiversity assessments in the Pondoland region. In terms of habitats, for both forest and grassland there was a large difference in the invertebrate communities at different sites, even over relatively short distances in grassland; shared habitat attributes clustered sites with more similar communities, for example, rocky ledges or the sea shore. All forest patches are a priority for protection.

Conservation and monitoring of invertebrates in terrestrial protected areas

Invertebrates constitute a substantial proportion of terrestrial and freshwater biodiversity and are critical to ecosystem function. However, their inclusion in biodiversity monitoring and conservation planning and management has lagged behind better-known, more widely appreciated taxa. Significant progress in invertebrate surveys, systematics and bioindication, both globally and locally, means that their use in biodiversity monitoring and conservation is becoming increasingly feasible. Here we outline challenges and solutions to the integration of invertebrates into biodiversity management objectives and monitoring in protected areas in South Africa. We show that such integration is relevant and possible, and assess the relative suitability of seven key taxa in this context. Finally, we outline a series of recommendations for mainstreaming invertebrates in conservation planning, surveys and monitoring in and around protected areas.Conservation implications: Invertebrates constitute a substantial and functionally significant component of terrestrial biodiversity and are valuable indicators of environmental condition. Although consideration of invertebrates has historically been neglected in conservation planning and management, substantial progress with surveys, systematics and bioindication means that it is now both feasible and advisable to incorporate them into protected area monitoring activities.