VITAL SIGNS

The waterbirds of Knysna Estuary

- DAVID ALLAN, IAN RUSSELL, JANE TURPIE, LORNA WATT & PAT NURSE

Situated along South Africa’s celebrated Garden Route, the town of Knysna is flanked by forested hills, pristine nature reserves and the expansive waters of Knysna Estuary. Snaking from the Outeniqua Mountains, the waters eventually spread into a broad basin before meeting the Indian Ocean at a narrow gap between the Knysna Heads. It is one of the largest estuaries in South Africa and has been ranked as the most important in terms of conservation value, taking size, type, rarity and biodiversity into account. Ranked 13th out of 258 estuaries in the country relevant to its importance for waterbirds, this jewel of the Garden Route is also a popular tourist destination and a prime location for holiday homes.

Despite its significance, its birdlife is relatively poorly studied in comparison to several large South African estuaries; the first thorough waterbird count was made in January 1979 by the erstwhile Western Cape Study Group. The most comprehensive information comes from the Coordinated Waterbird Counts Project (CWAC) which, since January 1993, has conducted counts at low tide in summer and winter over an impressive 30 years.

The typical community of large waterbirds comprises just over 60 species, dominated by ducks, resident and migratory waders, gulls, terns, cormorants, ibises, spoonbills and herons. The list of vagrants boasts southern Africa’s first claimed Spotted Sandpiper in the mid1800s (although this specimen can no longer be traced) and the sixth Lesser Yellowlegs, seen in November 2010. 

By the numbers