Eland saving Strandveld vegetation

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Unbeknown to most Cape Town residents, a herd of eland (Tragelaphus oryx) have been introduced into False Bay Nature Reserve on the Cape Flats to browse on available Strandveld every day. The Cape Flats, with its high urban population and reputation of crime, may seem like an unlikely place to reintroduce the world’s largest antelope. This unique project however is making it possible to save an endangered vegetation type.

Photo: Dalton Gibbs

The Gantouw Project

The project in question is the Gantouw Project, which aims to save Cape Flats Dune Strandveld through reintroducing the large herbivores which once roamed the landscape and kept the vegetation in check. The main working tools of this project are five eland that browse in the vegetation daily under the watchful eyes of field rangers and return to stay in a safe boma at night.

The Gantouw Project was started by the Cape Town Environmental Education Trust in 2015. Through this pilot project, the trust wants to determine if eland can be used as a sustainable and practical vegetation management tool in Cape Town. This indigenous vegetation type requires browsing to prevent bush encroachment.

Gantouw is derived from the Khoi word for ‘eland path’ – a route these large browsers once took across the Hottentots Holland Mountains.

Strandveld

Cape Flats Dune Strandveld occurs along the False Bay coast from Muizenberg to Gordon’s Bay and is endemic to the Cape Flats. It occurs nowhere else on earth. It is an endangered vegetation type growing on the old marine sands of the Cape Flats which are nutrient-poor and alkaline. “Unlike fynbos, Strandveld forms a dense thicket, and is filled with resprouting plant species,” says Dalton Gibbs, the southern regional manager of the Environmental Management Department at the City of Cape Town. Resprouting plants require intensive browsing as part of their lifecycle. “The eland keep the Strandveld in check and promote species diversity,” says Gibbs.

Strandveld plant species occur in patchy clumps surrounded by open spaces created by animal activity. Unlike the more familiar Fynbos, Strandveld plants produce fruits that are dispersed by animals.

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An eland in its boma. Photo: Dalton Gibbs

Threats to the Cape Flats Dune Strandveld

Strandveld vegetation relies on fire, herbivory (consumption of plant material by animals) and seasonal flooding to survive. “The underlying ecological driving forces which underpin Strandveld have been severely disrupted over the past two centuries,’ says Gibbs. “The most prominent of these is the reduction in groundwater over the past 70 years in order to facilitate urban development.” Alien vegetation further exacerbates the situation.

Furthermore, hippo, eland, black rhino and ostriches were replaced by domestic livestock at the end of the colonial period. Goats and other livestock would have fulfilled the Strandveld’s browsing requirements but in the last 50 years, livestock numbers have also dropped due to urbanisation.

Browsers tend to focus on new growth and shoots that are higher in nutrients. Older growth is not eaten and dies off to become fuel load. “Remove the large herbivores and the plants produce a greater fuel load,” explains Gibbs. “The greater the fuel load, the hotter and more frequent the fires.”

“Fire regimes have been similarly disrupted, with fires occurring earlier in the season,” says Gibbs. In some areas there have not been regular fires in many years, this means when there is a fire it is extremely hot and damaging. Bringing eland into the vegetation will make a difference in restoring the Strandveld to what it once was.

Eland helping save endemic butterflies

But there are more benefits than just intact, natural vegetation. By helping restore the Strandveld the eland are indirectly helping two critically endangered butterfly species – the Barber’s Cape Flats ranger (Kedestes barabarae bunta) and False Bay unique ranger (Kedestes lenis lenis). Both butterfly species are endemic to the Cape Flats region. Much of their habitat has been destroyed by urbanisation, alien species and an increased fire frequency.

The Barber’s Cape Flats ranger butterflies face the biggest threat. It is estimated that there are only around 60 individuals left. The Barber’s Cape Flats ranger has a restricted range and is currently only found in False Bay Nature Reserve where the eland are working hard to restore integrity for the Strandveld. The Barber’s Cape Flats rangers live in sword grass (Imperata cylindrica) as this is the host plant for their caterpillars.

If the eland do their job, the Cape Flats will be ablaze with the scarlet hues of candelabra lilies (Brunsvigia orientalis), Cape snow daisies (Dimorphotheca pluvialis) and rooipypie (Gladiolus cunonius) in seasons to come, and not raging fires.

Written by: Georgina Lockwood

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