South Africa is home to over 500 species of herpetofauna (> 130 species of amphibians, Measey et al. 2019; > 400 species of reptiles, Tolley et al. 2023a) of which > 50% are endemic or near-endemic to the country (Tolley et al. 2019). Several species are considered to be of conservation concern (Tolley et al. 2023a), with their primary threat being habitat loss via agriculture, mining, urbanisation and other anthropogenic land-use changes (Tolley et al. 2019, 2023a). Ensuring that South African herpetofauna are protected in conservation areas (i.e., national and provincial reserves, etc.) is thus important for maintaining the high diversity, richness and endemism of these animals in the country. However, baseline occurrence data for many herpetofaunal species are sparse in some parts of the country because of limited sampling (Barends et al. 2020; Tolley et al. 2023b), especially in the arid Karoo region in the Northern Cape province (Conradie et al. 2016; Telford et al. 2022).

Meerkat National Park (MNP) is a recently established protected area situated in the Northern Cape province of South Africa (Figure 1) and is more than 135 000 ha in area (South African National Parks [SANParks] 2022). The park is situated roughly 100 km from the towns of Carnarvon to the southeast and Williston to the southwest. Historically, the area consisted of several farms that were primarily used as rangelands for domestic livestock farming. In 2017, the land was acquired by the National Research Foundation (NRF) and South African Radio Astronomy Observatory (SARAO) to support the Square Kilometre Array (SKA) radio telescope project. The area was officially declared a national park in March 2020, managed by SANParks (SANParks 2022).

Various terrestrial fauna and flora occur within the MNP, but considering the limited number of records in public databases, the area appears to have been historically poorly sampled, particularly concerning the herpetofauna. In 2023, SANParks commissioned several surveys to generate baseline species lists of different taxonomic groups in the park. In this study, we report on the results of a nine-day herpetological-focused survey that aimed to provide a foundational species list of the amphibians and reptiles in MNP.

Based on species occurrence records and inferred distributions, we estimated that at least 40 species of reptiles and amphibians occur in MNP. Our targeted survey confirmed the presence of six of seven species of amphibians and 24 of 35 species of reptiles in MNP, doubling the number of confirmed herpetofauna from 14 to 30 species, as well as providing a 232% increase in the number of herpetofaunal records for the park. Increased sampling is likely to yield more reptile species, as evidenced by species accumulation curves, which did not asymptote, the predicted species list based on IUCN distribution maps, and asymptotic species richness estimators. In addition, while our sampling improved on previous geographic coverage from 13 to 18 (out of 32) pentad grid cells, much of the park remains unsurveyed. Additional surveys targeting those areas could potentially aid in increasing knowledge of the herpetofaunal species richness and diversity in MNP.

Of the species recorded in MNP, small range extensions were recorded for two species. The leopard tortoise, Stigmochelys pardalis, was not predicted to occur in the park (Hofmeyr & Baard 2023) but was observed in several pentads to the east and southeast of MNP, approximately 50 km west of the nearest records of native populations. Similarly, the bug-eyed house snake, Boaedon mentalis, was predicted to occur only marginally in the western regions of the MNP, but our records confirmed that the species also occurs in the east of the park, outside of its current inferred distribution (Conradie et al. 2023). Furthermore, a new record from iNaturalist (www.inaturalist.org/observations/255269037) from November 2024 was further east of our records, supporting the wider distribution of B. mentalis. Taken together, our records and those from iNaturalist allowed us to adjust the distribution polygons for both species (Figure 1-A1). In addition, while not a range extension, our observations of bullfrogs (Pyxciecephalus adspersus) are also of interest for the park as the species is rare in the region, and our records in MNP fill in a gap in the occurrence records and confirming that the park offers a suitable refuge for the species given the range of available water sources.

The majority of species recorded in MNP are categorised as Least Concern per the IUCN Red List. Only Chersobius boulengeri (Endangered) and Psammobates tentorius (Near Threatened) are of conservation concern (see Table 1). Importantly for these species, the park provides an ideal haven with suitable habitat that includes several rocky ‘koppies’, outcrops and ridges that C. boulengeri prefer, and sandy substrate with succulent vegetation suitable for P. tentorius. However, our observations of these tortoise species were of deceased individuals. Thus, while we can confirm these species are present in the park, their abundance and welfare are uncertain. Further evidence is required to ascertain the population status of these two species in MNP.

Several species expected in the park were neither detected during our survey nor reported on previous surveys. This is unsurprising given the low detection probabilities of some reptiles (Mazerolle et al. 2007) and the short duration of our survey. Future surveys could assist with detecting additional herpetofaunal species in MNP and would provide a more comprehensive list of species in the park. However, some common species that we expected to be abundant (e.g., Agama atra, or Pachydactylus capensis) were not recorded despite the multiple sampling approaches used. Moreover, we found no fossorial lizards (e.g., Acontias spp., Scelotes spp.), no monitor lizards (Varanus albigularis), and no terrapins (e.g., Pelomedusa galeata). Surprisingly, observations of some typically abundant Karoo species were low. For example, we observed only five individuals of Pedioplanis lineoocellata, a species which is typically among the most abundant lizards in the Karoo (KA Tolley pers. obs. 2018). While this might be attributed to a recent drought experienced in the region (SANParks 2022), previous reptile surveys in other parts of the Karoo also under and following drought conditions yielded substantially greater numbers of lacertid observations (Telford et al. 2022). Unfortunately, without data before the drought to contrast against, we cannot provide evidence in support of or against this hypothesis.

Overall, our herpetofaunal-focused survey of MNP provided a substantial increase in the number of records of amphibian and reptile species in the park. However, it is clear that further sampling is required to gain a more complete species list for MNP and to assess trends in population abundances. Additional surveys or long-term surveys are likely to result in additional species detections that can build on the list we produced here. In addition, there are several areas of the park that remain unsampled that could potentially yield additional species. This study therefore provides a provisional list of the species present in MNP, which can act as a solid baseline for further surveys.