Department of Statistical Sciences
University of Cape Town
| Avian Demography Unit
Department of Statistical Sciences University of Cape Town |
|
 Photo Doug Harebottle |
Rondevlei Nature Reserve is probably the most important breeding locality on the Cape Peninsula for colonial waterbirds, and probably supports the largest Sacred Ibis breeding colony in the south-western Cape. The reserve also supports significant numbers of Glossy Ibis, Cattle Egret, African Spoonbill, Blackheaded Heron, Grey Heron and Purple Heron during the breeding season which usually spans September to December. The birds use up to three of the four reed-islands in the vlei in which to build their nests.
To date a total of seventeen ringing sessions have taken place, nine in 2002, eight in 2003 and three in 2004. A summary of the number of colour-ringed birds is given below.
| Species | 2002 | 2003 | 2004 |
| Sacred Ibis | 476 | 884 | 71 |
| African Spoonbill | 14 | 1 | 2 |
| Blackheaded Heron | 13 | 11 | 1 |
| Grey Heron | 9 | 21 | 7 |
| Reed Cormorant | 4 | 5 | 0 |
| Blackcrowned Night Heron | 3 | 8 | 2 |
| Cattle Egret | 1 | 67 | 0 |
| Purple Heron | 1 | 6 | 1 |
| TOTAL | 521 | 1003 | 84 |
Thanks are due to Dalton Gibbs, reserve manager at Rondevlei, and his staff (Justin Miller, Crispin Barrett, Lynden Rhoda, Edward Moses, Theo Geland, Adrian Khan, Lesley-Anne Williams, Tshepo Mamabolo, Tamaryn Allan, and Adele Pretorius), Clifford Dorse, reserve manager at Zandvlei Nature Reserve, and his staff (Erica Foot), the Tygerberg Bird Club ringers (Peter Nupen, Margaret Macall and Bob Ellis), Graham Grieve, Paul Bremer, Darrel Lester, Kim Lester, Nina Lester, Steven Lester, Andrea Deary, Derek Noffke, Diella Noffke and Michael Brooks for their assistance in catching and ringing waterbirds at Rondevlei.
| Description | Photos |
| A juvenile Sacred Ibis being fitted with a red Darvic ring. |  Photo Doug Harebottle |
| Two juvenile Sacred Ibis awaiting release after being fitted with metal and red rings, September 2002. |  Photo Doug Harebottle |
| The two Sacred Ibis chicks back in the Rondevlei heronry. The red colour-rings are quite visible from a distance and should be able to be seen easily with binoculars or a telescope. |  Photo Dalton Gibbs |
| Two of the Grey Heron chicks that were fitted with red rings at Rondevlei Nature Reserve, September 2002. |  Photo Dalton Gibbs |
| A nest of an African Spoonbill among the Sacred Ibis colony. |  Photo Dalton Gibbs |
| Description | Photos |
| An individually colour-marked Cattle Egret fledgling. |  Photo Doug Harebottle |
| An individually colour-marked Sacred Ibis fledgling. |  Photo Doug Harebottle |
| A young Purple Heron with a unique colour-combination. |  Photo Doug Harebottle |
| Description | Photos |
| The first individually colour-marked Grey Heron for the 2004 season. |  Photo Doug Harebottle |
| The only two individually marked Black-crowned Night Herons ringed at Rondevlei for the 2004 season. |  Photo Doug Harebottle |
| One of 15 Sacred Ibis fitted with an unique colour combination. This bird was re-sighted during January 2005 at Rondevlei! |  Photo Doug Harebottle |
