Tracking the Invisible: Waterbird Discoveries on the Kgomo-Kgomo Floodplain
- Dr Jonah Gula
- 20 hours ago
- 6 min read
Dr. Jonah Gula holds a PhD in Ecological Sciences from University of KwaZulu-Natal (UKZN) and a MSc in Wildlife Ecology from Texas State University. Jonah’s research background is diverse: he has worked on species from black bears and bighorn sheep to river otters and sage-grouse. However, since 2018 his work has focused on filling knowledge gaps about poorly-studied African waterbirds. This work has led to collaborations across South Africa, Botswana, Namibia, Mozambique, and Zambia. His postdoctoral research at UKZN, supervised by Prof. Colleen Downs, is especially focused on waterbird movement in the region, and he currently has tagged birds moving through all southern African countries.
Floodplains are among the most dynamic ecosystems in southern Africa. With every rainfall event they transform, expanding into shallow wetlands, then slowly retreating again into grasslands and mudflats as the water evaporates. For waterbirds, these changes dictate everything. Foraging habitat appears and disappears, and birds must constantly track these shifting conditions. Understanding those movements is at the heart of my research.
I am a postdoctoral research fellow at the University of KwaZulu-Natal (UKZN), where my work focuses on the population ecology and movement patterns of waterbirds, particularly how they respond to rainfall and changing hydrology in floodplain systems. Over the past few years I have conducted fieldwork across southern Africa - including Zambia, Botswana and South Africa - using GPS telemetry to uncover how birds track ephemeral habitat conditions across vast wetland networks that often span multiple countries.
Recently I spent a week working on the Kgomo-Kgomo floodplain, operating from Zaagkuilsdrift Bird Sanctuary and Lodge, a location long known among birders for its extraordinary diversity of birds, especially waterbirds. In the years I have been catching and tagging waterbirds across southern Africa, this was the most productive week of waterbird ringing and tagging I have ever experienced. Within a few days my colleague and I managed to deploy 10 GPS tracking devices on waterbirds on the Kgomo-Kgomo floodplain. Several of these represented global firsts, and the diversity of species we caught and ringed on the floodplain was nothing short of remarkable.
One of the highlights of the week was fitting the first ever GPS tracking device on a Dwarf Bittern. This species is famously secretive, spending most of its life hidden deep within reedbeds and dense wetland vegetation. Because of this, its migration has remained largely a mystery. For the first time, we will now be able to follow an individual bird and see where it travels when it leaves the floodplain as the southern summer comes to a close. At the moment we have only a single bird tagged, but next summer we plan to deploy more tracking devices so we can start building a more complete understanding of the species’ movements.
We also tagged four Yellow-billed Ducks, another species that has never before been tracked. Despite being widespread across southern Africa, surprisingly little is known about how these ducks move between wetlands on a seasonal basis. Historic ring recovery data from ducks ringed at important wetlands such as Barberspan and recovered >1000 km away have demonstrated incredible movement potential of this species. With the tracking devices we have deployed at Barberspan and Kgomo-Kgomo floodplain, we will record the first detailed movements of this species to understand seasonal patterns in how they use southern Africa’s wetland network.
Another species we tagged was the Glossy Ibis, part of an ongoing study I’ve been running across the region. During this field session we added four more birds to the project, following four tagged at Barberspan and two tagged in western Zambia. So to date we have tagged a total of ten ibis. Already tracking data from Glossy Ibis tagged at Barberspan and in Zambia have shown that they are capable of large movements of hundreds of kilometres in a day. As the Kgomo-Kgomo floodplain starts drying later in the season, we expect to see similar movements from the birds tagged there.
Another exciting milestone of the expedition was the first deployment of a GPS tracker on a Greater Painted Snipe. At Kgomo-Kgomo we tagged an adult male and shortly after we tagged an adult female at Barberspan. These birds represent the first two Greater Painted Snipes tagged anywhere in the world and follow on the heels of ongoing tracking work on the Australian Painted Snipe by my colleagues in Australia. The Greater Painted Snipe is notoriously cryptic and difficult to study, and almost nothing is known about its movement ecology. These two birds will provide the first real glimpse into how this fascinating species uses the landscape, and we are planning more fieldwork in South Africa to deploy three more tags in the near future.
Beyond the excitement of tagging new birds, what really struck me during the week was the sheer abundance and diversity of waterbirds present on the floodplain, and in our mist nets! In many wetlands across southern Africa, catching and ringing waterbirds can be very slow compared to ringing land birds. However, netting waterbirds at Kgomo-Kgomo was so productive that on our first night we ended up staying out all night catching and ringing birds. Never in my experience have we been so overwhelmed with birds that it required an all-nighter.
We captured species that are rarely encountered during ringing or research work, including Baillon’s Crake, Black-winged Pratincole, Yellow-billed Egret, White-backed Duck, and Fulvous Whistling-duck. The ducks in particular were epic: we caught and ringed 64 ducks of 6 species in just two nights/mornings. Our only regret was that we did not have more tracking devices to deploy!
Much of this success comes down to the landscape itself. The Kgomo-Kgomo floodplain, with its mosaic of shallow wetlands, grasslands and seasonal pans, provides ideal habitat for a wide range of species, and the shallow pans where we worked held high densities of individuals and species. Operating from Zaagkuilsdrift Bird Sanctuary and Lodge, positioned right on the edge of the floodplain, allowed us immediate access to these habitats throughout the week.
At the moment, the tagged birds are still moving locally within the floodplain. But as the summer rains begin to decrease, the floodplain will start to change. As the floodplain begins to dry, many of these birds will almost certainly begin making larger movements to locate new foraging habitat elsewhere in the region. Thanks to the tracking devices, we will be able to follow these movements in near real time, mapping the journeys of these birds across southern Africa’s shifting wetland network.
For me, the week served as a powerful reminder of how important places like this floodplain are - not only for birders who come to experience its remarkable diversity, but also for scientists trying to understand how waterbirds survive in such dynamic environments. And when wetlands are as healthy and productive as Kgomo-Kgomo, it also makes my job as a scientist all the more exciting and successful.
I am excited to have started work on the Kgomo-Kgomo floodplain with the support of Zaagkuilsdrift Bird Sanctuary and Lodge, and I look forward to a return to continue my research there. I am confident that as the tracking devices begin to reveal new information, it will not only be me but also the birding community that loves Zaagkuilsdrift and Kgomo-Kgomo who will be amazed at what we learn about the species we tagged. Kgomo-Kgomo is just one piece of the puzzle of southern Africa’s wetland network, but it is clearly a critical one.
Zaagkuilsdrift Bird Sanctuary & Lodge, is recognised as one of South Africa’s most significant floodplain birding destinations, renowned for its exceptional warbler and LBJ diversity. The lodge offers purpose-built accommodation for birders, on-site hides, and immediate access to extensive wetland and grassland habitat. As active custodians of the Kgomo-Kgomo floodplain, Zaagkuilsdrift blends conservation commitment, community partnership, and owner-managed hospitality of the highest standard. Zaagkuilsdrift — Accessible. Authentic. Exceptional. https://www.zaagkuilsdrift.co.za/
