Glossy Ibis and Common Greenshank at Lake Victoria

Field Observations

Two Species, Two Migration Strategies

During visits to the Ssese Islands in October 2024 and again in January 2026, the contrast between these two Palearctic migrants became clear. The Glossy Ibis, recorded as just 2 individuals at Banga Island, is one of the less predictable migrants in Uganda's Lake Victoria region. Its metallic bronze-green plumage, iridescent even in overcast light, is unmistakable once learned. Most birds pass through Uganda on their way further south, which explains why sightings at any single site tend to be small in number even when populations across sub-Saharan Africa are stable.

The Common Greenshank tells a different story. Six individuals were recorded at Lutembe Bay during structured waterbird counts, making it the more reliably encountered of the two species along the northern lake shoreline. The Greenshank's preference for open mudflats and sandy shallows fits Lutembe's character precisely — this Ramsar-designated wetland offers exposed foreshore between patches of papyrus, exactly the habitat a feeding wader needs after hundreds of kilometres in the air.

Both species belong to a migration system that links the high-latitude breeding grounds of northern Europe and Siberia to the wintering wetlands of sub-Saharan Africa. The routes they follow have been refined over thousands of years, but they are not immutable. Habitat loss at stopover sites along the way can disrupt an entire migratory cohort's energy budget, which is why the continued integrity of lake-fringe wetlands like Lutembe and Mabamba matters far beyond Uganda's borders.

Banga Island and the Ssese Corridor

Banga Island, one of the 84 islands of the Ssese archipelago, lies roughly 60 kilometres southwest of Entebbe across the open water. Its position in the lake's northern basin places it directly in the path of migrants moving southward along Uganda's interior. The island has a rocky shoreline interspersed with papyrus beds and small sandy spits — ideal for waders and ibis resting after a night crossing.

During a three-day stay at Banga in October 2024, the overall species count reached 22 recorded from the two main Ssese survey points (Lutoboka and Banga combined), totalling 1,163 individuals. The Common Sandpiper was particularly numerous — 26 birds at Lutoboka and 21 at Banga, making it by far the most abundant Palearctic wader in this survey. The Glossy Ibis, appearing as 2 birds at Banga only, represents what ornithologists classify as a scarce but regular migrant in this corridor.

What the Ssese Islands offer that many mainland sites cannot is a degree of isolation from direct human disturbance. The islands are primarily forest-covered with fishing communities concentrated on a few larger beaches. The bird populations here are not subject to the agricultural drainage that has altered many mainland wetlands around Lake Victoria's shoreline. This may explain why Banga records migrants that are absent from more disturbed mainland sites.

Lutembe Bay: The Accessible Alternative

For those arriving at Entebbe Airport and wanting an immediate introduction to east Africa Lake Victoria's birdlife, Lutembe Bay is the obvious starting point. It lies on the northern shore of Murchison Bay, a 20-minute drive from the airport. The bay's shallow margins, combined with the presence of large horticultural farms that keep some areas of open water free from dense papyrus, create a mosaic of microhabitats that attracts both resident species and migrants.

The 2019 Uganda Bird Monitoring survey recorded 28 species and a significant total of individuals at Lutembe, with Grey-headed Gull dominating the counts at 912 birds on muddy islets. Among the Palearctic migrants, the Greenshank was recorded alongside Slender-billed Gull (29), Gull-billed Tern (11), Lesser Black-backed Gull (10), Ruff (6), and Marsh Sandpiper (4). This is a remarkably diverse assemblage of Palearctic visitors for a single site in Uganda's interior, and it reflects Lutembe's status as both an Important Bird Area (IBA) and a Ramsar site.

The site does face pressure, however. The surrounding area is heavily cultivated with flower farms that drain into the bay, and water quality has declined measurably in recent decades. During a visit in January 2026, water hyacinth covered portions of the bay margin that had been open water in previous years. The consequences for migrants that depend on exposed mudflats are direct — fewer available feeding stations means shorter stopover times and reduced energy replenishment before the next leg of the journey.

Reading Migration Through Numbers

One of the most useful aspects of Uganda's structured waterbird monitoring programme, conducted by NatureUganda in partnership with the Uganda Wildlife Authority, is its long-term consistency. The same sites are surveyed twice per year — once in January (peak migrant presence) and once in July (when most Palearctic migrants have returned to their breeding grounds). The comparison between the two seasons reveals the true scale of migration pressure on these sites.

In July, a survey like Lutembe Bay will record far fewer individuals and species than in January. The Greenshank will be absent; the ibis, if present at all, will be vagrants rather than migrant cohorts. This seasonal contrast is itself a data point — it shows that the lake's northern wetlands are functioning as genuine migratory wintering grounds rather than year-round resident habitat for most of these species.

For the Glossy Ibis specifically, the picture is more complex. Unlike the highly predictable waders, ibis movements show more inter-annual variation. A species that breeds across a wide range from southern Europe through Central Asia can appear in Uganda in variable numbers depending on conditions at its breeding sites and along its route. The 2 birds at Banga in 2024 may represent a small fraction of a much larger cohort that passed through at night or stopped briefly at other sites along the lake's western shore.

Conservation Significance for the East Africa Lake Victoria Region

East Africa's Lake Victoria holds a disproportionate share of the continent's freshwater bird diversity. Uganda alone lists around 160 waterbird species, of which 89 per cent are classified as water specialists. Within this community, Palearctic migrants form a significant seasonal component — species that are born in one ecosystem, mature in another, and depend on a chain of healthy wetlands to complete their annual cycle.

The Glossy Ibis and Common Greenshank are both classified under the Africa-Eurasian Waterbird Agreement (AEWA), which provides a framework for their protection across the flyway. Uganda is a signatory to both AEWA and the Ramsar Convention, which gives sites like Lutembe Bay formal protection status. In practice, however, the effectiveness of these designations depends on national enforcement capacity and on the sustained engagement of local communities who live alongside these wetlands.

NatureUganda's monitoring data, which extends back to 2006 for the Ssese Islands, shows that while species presence has been broadly maintained, population densities at some sites have fluctuated. The continued involvement of local rangers and community guides — [QUOTE: local guide on first impressions of the morning migration flights across the bay] — remains one of the strongest safeguards for these habitats in the long term.