#01 2021

Scientific riches retained at the SAEON Arid Lands Node

by Helga van der Merwe, SAEON Arid Lands Node

The end of 2020 brought about significant changes at SAEON’s Arid Lands Node with the retirement of the node manager, Dr Joh Henschel, and the end of wetland ecologist Dr Betsie Milne’s postdoc. Do not despair, however, these two scientists have subsequently accepted invitations to become SAEON research associates.

 Joh Henschel

Joh is an ecologist conducting environmental research in South Africa, Namibia and abroad. With an early background in marine biology, he has extensive experience in many terrestrial environments, particularly arid lands.

His MSc project demonstrated how bacteria affect the settlement of marine invertebrates. In his next study, he showed how female-dominated spotted hyaena clans are affected by male dispersal and cub survival. His postdoc on spiders highlighted aspects of behavioural, eco-physiological and ecological research on invertebrates and their interactions.

His second postdoc entailed field experiments that demonstrated how allochthonous (deposit or formation that originated at a distance from its present position) resources from highly productive aquatic systems represent subsidies that increase consumers’ impacts on terrestrial communities.

Joh led the development of long-term ecological research (LTER) networks in Namibia and facilitated LTER growth in South Africa and across southern Africa, connecting these infrastructures internationally to address questions of global change and anthropogenic effects on ecosystem integrity.

Joh’s overarching goal as SAEON research associate is to continue contributing towards arid lands research by conducting research, providing support to SAEON projects where appropriate, and popular writing. Examples of projects he is interested in are a review of brown locust population dynamics (based on a century of Agricultural Research Council data and literature), including collaboration with Wits University and the University of the Western Cape as well as fieldwork for this project.

Concurrently Joh is compiling a scientific paper of long-term (45 years) data of abundance and diversity of tenebrionid beetles, compiling an invited review of Southern Africa sand dune biota for a book on dunes, finalising a popular book based on his research of spotted hyaena ecology and providing inputs on Namib ecology for a book.

Other potential involvement may include providing support to two EFTEON projects (KIMTRI, Garden Route Gateway), continuing to provide support at Tierberg and Wolwekraal, and engagement with an international network on ecological restoration, including using some SAEON Arid Land Node sites (Tierberg, Wolwekraal, SKA) as focal sites.

Furthermore, Joh hopes to be able to support SAEON’s endeavour to secure historical data on the Karoo.

Betsie Milne

Betsie is our second new Research Associate, whose interest in biodiversity conservation began from a young age and evolved into a career. She obtained a BTech in Nature Conservation from the Tshwane University of Technology, a Master’s in Environmental Management from the University of the Free State and a PhD in Botany from Nelson Mandela University.

Her involvement in the mining industry of the Northern Cape since 2007 led to an increased awareness of the understudied ephemeral pans in the province. In 2016 she joined the SAEON Arid Lands Node as a postdoc, which led to ground-breaking research on these vastly neglected systems.

Betsie immediately hit the road (literally) and conducted an extensive survey across the Northern Cape, sampling 113 ephemeral wetlands, which led to a large amount of novel data on the distribution of large branchiopods. Most significantly, at least five new large branchiopod species were discovered. This project also highlighted the Northern Cape as a global large branchiopod biodiversity hotspot.

Betsie’s main research interests are temporary aquatic ecosystems in drylands and how these landscapes function in arid and semi-arid environments. Furthermore, she has an interest in the distribution of Branchiopoda (Arthropoda: Crustacea) in the temporary waters of southern Africa.

The publication of scientific and popular articles, and presentation of her research at numerous national and international conferences and forums, have disseminated information and conveyed her passion for wetlands in arid regions. Her representation as a committee member of the Northern Cape Wetlands Forum, and later as chairperson of this forum, shows her active involvement in supporting wetland research.

In 2020 Betsie also became a member of the National Freshwater Invertebrate Expert Group (large Branchiopoda) for the next National Biodiversity Assessment, a membership that will continue until 2025.

When asked about her most exciting career highlights, she includes:

  • The discovery of five large branchiopod species in the Northern Cape during her postdoc;
  • Being invited by Prof Brian Timms in 2017 to visit the dry lake systems in the Paroo region in Australia;
  • Being awarded a three-month scholarship to work with Prof Luc Brendonck at the Laboratory of Aquatic Ecology, Evolution and Conservation, KU Leuven, Belgium in 2019; and
  • A wet pan and its exciting discoveries.

The Arid Lands Node looks forward to continued collaboration with these two arid lands research specialists.

Joh introducing Betsie to Northern Cape wetlands

Joh studying a toktokkie beetle

Betsie sorting branchiopods in the Laboratory of Aquatic Ecology, Evolution and Conservation, KU Leuven, Belgium