The heronry on Robben Island is probably one of the largest off-shore breeding colonies for waterbirds in the southwestren Cape. During 2000 and 2001 the heronry supported close to 1300 nests consisting of 600 Cattle Egret, 600 Sacred Ibis, 100 Crowned Cormorant, 50 Little Egret and 4 Blackcrowned Night Heron pairs. The heronry was located amongst a large patch of Rooikrans (Acacia cyclops) trees on the southern end of the island. In 2002, the colony diminished to less than a third and abandoned the original site in favour of another Rooikrans-dominated area located just south of the harbour wall. Most of the Sacred Ibis abandoned the heronry and selected a grassland area on the western side of the island where they built their nests on the ground.
Three ringing sessions have taken place, two in 2002 and one in 2003. A summary of the birds colour-ringed to date is presented below.
I would like to thank Mario Leshoro (Robben Island Museum) for permission to ring on Robben Island and for arranging the logistics in getting to the island. The following people assisted with the catching and ringing of birds: Sue Kuyper, Mario Leshoro, Jane Underhill, Kathy Calf, Bill Watson, Peter Nupen, Kim Smith, Sam Wishart, Audrey Koester, Marius Wheeler, Michael Brooks, David Swanepoel, Martyn Peck and Ruben Fijn.