The Liesbeek River catchment area is a microcosm of South Africa when it comes to bird life, and, with ongoing habitat restoration efforts, could even be manipulated to suit certain species.
This is one of the fascinating findings to emerge from the Friends of the Liesbeek (FOL) annual general meeting, at the Vineyard Hotel, last week, when committee members spoke about key developments along the river in the past year.
Guests were treated to wine and snacks and heard from researchers Jessleena Suri, of the Percy Fitzpatrick Institute of African Ornithology at UCT, and frog expert and sustainability consultant, Peta Brom.
Chairman Phil McLeansaid a deal had been struck with SABMiller to provide more funding to the 25-year-old organisation, which would support the Liesbeek maintenance team’s efforts to make improvements to the river and surroundings.
Project manager Kyron Wright described the organisation’s successes and challenges in the past year.
A lot of work had been done to clear alien vegetation along the 9km stretch and rooiels, Cape saffron and other trees had been planted. Routine maintenance along the upper reaches of the river had also gone smoothly.
However, Mr Wright said the area from Belmont Road in Rondebosch to Alma Road in Rosebank remained the FOL’s “most problematic” with a “significant homeless problem”.
He said people gave away their old camping tents, which the homeless were pitching along the river. “As a result there are frequently human ablutions in the river,” Mr Wright said.
By stark contrast, the stretch from Alma Road to the N2, the focus of much of the maintenance team’s efforts, had been completely overhauled in the past year. “We cleared the overgrown strip just before the greenbelt, as this had become a nest for the homeless. Then we began scraping the canal clean, while also planting 10 trees. Our main focus, however, was the retention ponds, which had been neglected for 15 years,” Mr Wright said.
“There is so much work that has been done. We spent a lot of time clearing out the typher, and then, after digging a trench, began reconnecting the first and the second ponds. The water supply has been improved dramatically, and ultimately we want to use the water as a bio-retention facility.”
Ms Suri spoke about her honours project, “Urban Rivers and Ecological Function: Bird Diversity in the Liebeek Catchment”, which explored 89 sites along the route.
“Birds are highly visible in the catchment area. In my research, I encountered 99 species, of which 64 were along the river, but there are known to be 120 species,” she said.
“That means that if you look at bird distribution in the country, as a whole, the Liesbeek catchment is a microcosm of South Africa.”
Interestingly, a number of raptors featured among this number, including goshawks and spotted eagle owls.
“A number of incredibly rare birds have also been spotted, including the fishing owls and the snowy eagret, the second most popular twitch in South Africa,” said Ms Suri.
“The Liesbeek is highly recognised by birders, and people are noticing the visible differences that have been made. The implication of my research is that different habitats preserve species, and habitat restoration can be manipulated to favour certain species.”
Ms Brom is investigating the prevalence of frogs and toads in gardens in Observatory, Rosebank and Little Mowbray.
“To date I have visited 44 gardens, and thankfully there has been a huge response from the community,” she said.
Particular species appear to be more common in certain parts of the research area. For example, the western leopard toad tends to proliferate around Observatory, while the Cape sand toad seems to relish conditions at Rondebosch Common.
Other species she has encountered are the Cape river frog (Rosebank Green), the clicking stream frog (everywhere) and the raucous toad (Observatory).