Cape’s wetland wonder

Published Sep 29, 2013

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Cape Town - It’s the day after heavy rains, and near Century City, Cape Town, birds are having a great time splashing in the water that has collected in lakes alongside the N1.

The water table here is high, and I’m wondering how Intaka Island, the place I’m about to explore, has fared in the extreme weather.

Intaka Island is an unexpected find, a green lung surrounded by the dense development that is Century City – office blocks, housing, and the shopping centre. For those who never venture beyond the N1 into the area, it’s a complete surprise.

Intaka Island is an artificial wetland created where the “sewe pannetjies” used to be – a natural wetland system that was overgrown by Port Jackson before development began there more than 20 years ago. Eight hectares of sandplain fynbos was considered worth preserving, and forms part of the 16ha wetland. Eight hectares were set aside for an artificial wetland for year-round filtering of the water from the canals that were built, and the other 8ha is a seasonal wetland.

Intaka Island now also has an environmental education centre, which is attended by anyone from toddlers to 90-year-olds, says Angelo Tilling, our guide.

Tilling takes school groups on tours of Intaka: “We teach them to look at nature in a different way,” he says. His previous job was dealing with the water, now he is an eco centre environmental assistant. One activity he does with groups is pond dipping – collecting water at various points and evaluating it under the microscope to assess the health of the water.

There are four cells, or ponds, which purify the water – the first two use weeds, the third sun and wind, and the fourth is a shallow pool where water sits for a period. The water is pumped back into the system after 85 days.

All the canals in Century City are man-made, and storm drains feed into pond number one, explains Tilling. In summer, when the levels get too low, recycled water from a sewerage works is pumped from Killarney. The water coming into the ponds is rich in nutrients, and algae, azolla, pond weed, duck weed, and hornwort thrive on these. Various biological controls are used to limit overgrowth, such as weevils for the azolla and barley straw for young algae (as well as mechanical removal of older algae). The barley straw is packed in sacks, and as it decomposes it releases an enzyme that kills the young algae.

As for my fears about high water levels after the rain, Tilling explains that when necessary the water is drained into the Black River and water levels return to normal within three to four hours.

As we walk around the area, which has wheelchair-accessible paths, Tilling’s sharp eyes catch sight of many birds, which he names for us. The rich variety of birdlife makes this a birder’s destination, with some rare specimens here and plenty of others. Intaka means bird in Xhosa, and when the sun appears, birdsong surrounds us.

There are four indigenous fish species here and 212 plant species, including 25 on the Red Data List of endangered plants. A medicinal garden, along with a sustainable indigenous fynbos and sandplain fynbos garden, is now a year and a half old. I spot an unusual plant in the natural wetland area, one I haven’t seen before, covered in pink flowers. It’s called Luibos, I’m told, and we find it again in the sandplain garden. Here are confetti bushes in full flower, as well as vygies and two varieties of wild fig.

Intaka Island is one of the few places in Cape Town where you can still find this type of sandplain fynbos vegetation. Many of the plants cultivated on the island are suitable for Western Cape gardens. Being indigenous to the area, they tend to cope well with the sandy soil, strong winds and dry summers, which are typical of the Cape.

The wetland system was landscaped about 15 years ago, and is known as Blouvlei. First the invasive Port Jacksons were removed, a small hill was created called Bird Mountain, and plants and trees were planted to create habitats and ecosystems.

Tilling constantly spots birds – it’s becoming a passion, he says. He points out a Red Bishop, picks up the song of a Karoo Preener, and sees a Cape Bulbul.

The seasonal wetland is full of water now, and we see a Flamingo fly over. There’s a Grey Heron, a Red-knobbed Coot, a Water Dikkop.

“There are two Red Kingfishers, four Malachite Kingfishers, but you have to be very patient to see them,” says Tilling.

He points out a bush on the second pond where a family of crowned night herons live.

This is a twitcher’s paradise. On a very good day you can spot 60 to 80 species, he says.

“I’ve developed a passion for birds. My own list is up to 85, and that includes four rare birds. I recently saw a Klaas’s Cuckoo and a Giant Kingfisher.”

In pond three are two heronries. A number of birds use these for breeding and roosting. These heronries have been recognised internationally for their simple construction and success in attracting birds. To prevent the guano from the heronries creating high phosphate levels in the water, there are tanks below to catch the guano. From here it is pumped on to land and used for fertiliser.

Pond three is purified by sun and wind. Pond four is surrounded by a hide – it’s a quiet spot where you can watch the birdlife. Artificial banks have been built to attract and encourage birds to breed.

Intaka Island is truly an oasis among the surrounding built environment. It’s surprisingly quiet, and you’d be hard pressed to know there’s a busy highway not far away.

Who visits the island? People in the area, people who work in Century City, birders, and school groups, says Tilling. It’s open to the public at a small cost, every day except Christmas.

There are 2km of footpaths, and you can take a ferry on the Grand Canal and around Intaka Island. It takes about 35 minutes. - Cape Argus

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