OVERBERG RENOSTERVELD TRUST

Just six observers make global case for renosterveld

A team of just six people managed to log an incredible 922 renosterveld species sightings over the course of four days in September. This is once again testament to the vast diversity of species, from animals to plants, you’ll find in renosterveld.  

Every year the Great Southern BioBlitz serves as the ideal opportunity for the Overberg Renosterveld Trust team and friends to photograph, capture on the iNaturalist app, and thereafter identify the observed species. This event takes place across the southern hemisphere, as an opportunity for conservationists and citizen scientists to learn more about the natural world and contribute to a global database of the world’s incredible biodiversity.  

The Great Southern BioBlitz is particularly important for renosterveld because it takes place as the world’s richest bulb habitat flowers in spring. This year the event occurred between 20 and 23 September 2024.   

The ORT team, consisting of Odette Curtis-Scott, Grant Forbes, Tevin Adams, Cliff and Suretha Dorse, with inputs from Michelle de Wet and Ben de Wet who joined for part of the blitz, contributed 2,719 observations in the Overberg, with 922 confirmed (identified) species. This included many very special sightings, such as a ‘new’ species of jumping spider.  

Digger Bee (Amegilla sp.), Bladderhopper (Bullacris sp.), Brown Vapourer Moth (Bracharoa dregei).

Striped field mouse, Southern black Korhaan, Rhene konradi.

Black Cocktail Ant on Diosma fallax, Neddicky (Cisticola fulvicapilla), Klein Karoo Triton (Tritonia baker).

Sheathing Spiderlily (Ferraria variabilis), African Spoonbill (Platalea alba), Common Satin (Geissorhiza aspera).

Regarding the GSB highlights, Odette says: I got down on the ground to look at a tiny plant, and out of the corner of my eye, I saw something absolutely miniature, but very colourful. When I looked closely, it was a bright orange jumping spider with iridescent blue markings. It was a mature male and was literally just 2mm in size. The experts say they think it’s a new species that is currently being described within the genus Tanzania.

I was also so excited to find an inland Black Button Spider (Latrodectus renivulvatus). These are such maligned species – but they’re actually very shy and secretive. During the GSB, I saw a few threads of a web sticking out in a hole. And then I found the spider in a retreat in the hole. I’ve dreamed of finding a mature female like this one for years, so this was such a treat.

I’ve never seen a Tiger Beetle (Cicindela lurida) before – so spotting them during the GSB really stood out for me. This is a very cool insect – a super fast-moving, predatory beetle.

 Black Button Spider (Latrodectus renivulvatus), Tanzania, Tiger Beetle (Cicindela lurida)

Grant says: They may be ecosystem engineers, but ants are often overlooked. But during the GSB, an almost prehistoric ant, called the False Trap Jaw Ant (Genus: Anochetus) caught my eye with its elongated mandibles that end in an acute tooth. Our host site during the GSB at Melkhoutebosch has very Karoo-like habitats, and that’s why they are home to these Baster Slag Yster Mure, as they’re known in Afrikaans. These little ants are predacious, using their trap jaw mechanism to seize prey and jump backwards. If they’re disturbed or attacked they play dead; so these guys definitely caught my attention.

The second sighting that was very cool for me was the Black Thread Snake or Kaapse erdslangetjie – which you can find out more about on our Renosterveld Field Guide app. This endemic snake measures up to 20 cm. These small guys are blind and prey on ants and termites and they can secrete pheromones to protect them from the ferocious attacks of ants and termites.

Seeing the salmon-pink flowers of Aspalathus rosea was a real highlight. This species is Endangered and they are mostly found in remnants of renosterveld and renosterveld-fynbos areas. The species has lost so much of its habitat due to agriculture and invasive alien plants and that makes the work of the ORT so important – as we work with farmers to secure sites forever. Fortunately the site where we found the Aspalathus is an easement already. We were lucky enough to find this very cryptic species because they grow low to the ground and are often hard to find, but in flower they really pop.

Aspalathus rosea, False Trap Jaw Ant (Anochetus), Black Thread Snake

The umbrella project

This includes all the regions participating across the southern hemisphere. In the umbrella project, 261,758 observations were captured, with 26,187 species observed, and 8,561 observers.  

The Overberg district placed fifth overall. What made the Overberg’s performance notable was the low number of observers – just 86 people participated, and the region ranked just 28th for the number of observers. As such, Overberg participants observed on average 115 species, versus 23 observations per observer across the rest of the umbrella project.  

– In the umbrella project, ORT Conservation Manager Grant Forbes took 10th spot with 1,310 observations and 6th place for the number of species (624 species).  

– CEO Odette Curtis-Scott placed 25th for observations (927 observations) and 11th for the number of species observed (484).  

Southern Africa 

In Southern Africa, the Overberg placed 4th overall with 9,911 observations and 5th for species observed with 1,702 species.  

– Grant made the fifth most observations, but placed FIRST across Southern Africa in terms of species observed.  

– Odette came in 14th for observations and 6th for species observed.  

Overberg

The ORT’s observations amounted to 27% of all the Overberg region’s observations.  

– In the Overberg, Grant took 1st place for most observations and species. 

– Odette took second place in terms of both observations and species observed. 

Our sincere thank you

– We’re very grateful to Melk Houte Bosch Guest Farm for providing us with the base from which we could explore and blitz the area. This truly is a worthy break away. And they are also making such a valuable contribution to renosterveld conservation through our Easement Programme.  

– Also, thank you to the Ford Wildlife Foundation for providing us with the vehicle which allowed us to travel to the sites.

– And thank you to each of the landowners who provided access to their farms, to participate in the GSB 2024.  

    ORT © 2012 - 2024 | Trust no IT851/2012 • PBO no 930039578 • NPO no 124-296