Tiny birds, vast journeys: Inside SA’s first shorebird tracking project

A groundbreaking new research initiative is set to uncover the remarkable journeys of migratory shorebirds by deploying satellite tracking devices on species such as the Curlew sandpiper and Grey plover — marking a first for South Africa.

Led by BirdLife South Africa, the project focuses on tagging, colour-ringing and monitoring birds at key coastal sites, including the Berg River estuary, to better understand their movements along the Africa–Eurasian Flyway, a major migratory route covering Europe, Asia and Africa. The aim is to identify critical habitats and inform conservation efforts that stretch across continents.

The organisation describes the initiative as a major milestone for southern Africa, where the migratory routes, stopover sites and breeding grounds of local shorebird populations have long remained poorly understood.

“While tracking studies have been conducted elsewhere along the flyway, few tagged birds have reached South Africa, leaving the migratory routes, stopover sites and breeding areas of South African populations poorly understood,” said BirdLife South Africa.

“This is the first time long-distance Palearctic migratory shorebirds, in this case the Curlew Sandpiper and Grey Plover specifically, have been fitted with tracking devices in South Africa.”

For Jessica Wilmot, the flyway and migrants project manager, the project builds on years of work along the country’s west coast while expanding its reach far beyond national borders.

“BirdLife South Africa has worked along the West Coast for many years and this project builds on that foundation, showing not only how landscapes are connected within South Africa but how shorebirds link us to critical wetlands across the continent,” she said.

“Following the recent Ramsar Conference of the Parties 15 in Victoria Falls, it’s a timely reminder of how important these ecosystems are.”

Rebuilding a lost research capacity

Wilmot said efforts to track migratory shorebirds in southern Africa had historically been constrained by cost, capacity and technology.

Tracking devices remained expensive and, until recently, many were too large for small-bodied species such as Curlew sandpipers, she said. Globally, most tracking research had focused on Europe, where relatively few birds travelled as far south as Africa.

At the same time, South Africa had experienced a decline in wader ringing and trapping expertise. Decades ago, the country played a leading role in flyway research through Safring, the South African Bird Ringing Unit, but reduced funding and capacity made large-scale wader work, which required specialised teams and coordinated field efforts, increasingly difficult to sustain.

What had changed, Wilmot said, was a renewed focus on flyway-scale conservation combined with advances in lightweight tracking technology that now made it possible to safely monitor smaller species.

Crucially, the project had been enabled through international collaboration. Partnerships with the department of ornithology at Max Planck Institute for Biological Intelligence and Wetlands International had provided both the technical expertise and the tracking devices themselves. Long-term funding support from the Royal Society for the Protection of Birds and the Ecological Restoration Fund had also been central.

Together, the developments mark what Wilmot described as an important step in rebuilding regional capacity, demonstrating the power of collaboration in advancing conservation across an interconnected flyway system.

Global shift in conservation thinking

The project is unfolding against a broader shift in how migratory species are understood and protected globally.

At a recent meeting of the Convention on Migratory Species (CMS), governments formally recognised “marine flyways” for the first time — a landmark development in ocean conservation.

The framework identifies vast migration highways used by more than 150 seabird species across 54 countries, highlighting how threats such as climate change, invasive species and overfishing operate across entire ocean basins.

While the CMS decision focuses on seabirds, conservationists say the principle applies equally to shorebirds moving along continental routes such as the Africa–Eurasian Flyway — reinforcing the need for coordinated, cross-border conservation.

Complex, unpredictable journeys

Early tracking data from the South African project is revealing how complex and variable the migrations can be. 

“This variation in movement patterns is one of the most exciting — and least understood — findings,” Wilmot said.

The birds appeared to travel in loose flocks, with their routes shaped by a mix of external factors such as wind and weather systems and internal dynamics including experience and the possible role of “leader” individuals.

“There also appears to be a degree of flexibility and decision-making along the way,” she said. “Some individuals have already shown unexpected behaviour, including backtracking or deviating from anticipated routes.

“Understanding these dynamics is exactly why this research is needed. Migration is far more complex and adaptive than we previously assumed.”

Rethinking conservation priorities

Early results show that many birds are using sites recognised as important, including the Makgadikgadi Pans, which are designated as key Biodiversity Areas.

“This reinforces the importance of these landscapes and strengthens the case for their continued protection and management,” Wilmot said.

At the same time, the tracking data was beginning to highlight how birds used areas beyond the boundaries of recognised conservation sites — and in some cases, entirely new locations. “As the dataset grows, this information can inform the expansion of protected area boundaries or the identification of additional priority sites,” she said.

“Ultimately, effective conservation depends on understanding the full network of habitats these birds rely on. Without tracking data, we simply don’t know whether the current system of protected areas is sufficient to support them throughout their migration.”

Critical estuary under pressure

One of the focal sites of the project, the Berg River estuary, is among South Africa’s most important coastal wetlands but also one under increasing strain.

Wilmot said the system had been shaped by historical and ongoing changes, including altered river flows, infrastructure development and the expansion of agriculture and urban areas.

Reduced freshwater inflow because of upstream abstraction, declining water quality and disturbance from recreational activities and overfishing were degrading critical habitats such as saltmarsh.

More recently, prolonged drought had intensified the pressures, leading to hypersaline conditions, vegetation die-off and further destabilisation of the ecosystem.

More broadly, she warned that estuaries remained under-protected in South Africa despite their importance for biodiversity, ecosystem services and climate regulation through “blue carbon” storage.

“The loss and degradation of these systems not only threaten waterbirds, but also reduce their capacity to buffer climate change, impacting both biodiversity and the communities that depend on them for their livelihoods,” Wilmot added.