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Scientific Name | Cyperus sensilis Baijnath |
Higher Classification | Monocotyledons |
Family | CYPERACEAE |
National Status |
Status and Criteria | Near Threatened B1ab(i,ii,iii,iv,v) |
Assessment Date | 2007/07/23 |
Assessor(s) | L. von Staden |
Justification | Restricted to the highly transformed KwaZulu-Natal coast (EOO 5300 km²). Known from seven highly disjunct locations, although it cannot necessarily be assumed that the species does not occur elsewhere, as suitable habitat exists in the intermediate areas. These potential locations are highly transformed by commercial sugarcane and ongoing coastal development. We estimate that there are 10-15 locations. This species is declining throughout its range due to coastal development, forestry plantations, urban expansion and commercial sugarcane. The only populations that are still healthy are in the St. Lucia region, where there are also stresses due to development, subsistence agriculture and interference with the hydrology of the system. |
Distribution |
Endemism | South African endemic |
Provincial distribution | KwaZulu-Natal |
Range | KwaZulu-Natal coast, from Umdoni Park to St Lucia. |
Habitat and Ecology |
Major system | Freshwater |
Major habitats | Indian Ocean Coastal Belt |
Description | Coastal grasslands and dunes, associated with seasonal pans, forms a conspicuous zone around the water edge, 5-50 m. |
Threats |
| This species has probably lost a much of its habitat to forestry plantations in the past around St Lucia, although the extent of loss of to the population and the time frame cannot be estimated accurately. Forestry plantations, especially gum trees, have extensive impacts on the water levels of wetlands and drainage lines, and therefore, although much of the forests in the area is owned by a conservation minded company, the impacts of the plantations on the water levels of wetlands are likely to be ongoing.
In the Durban area the wetland systems are disrupted and polluted by surrounding urban areas, and although the species appears to still occur in degraded wetlands, there may also have been declines in the past due to drainage of wetlands for development.
The coastal area between St Lucia and Durban is so excessively transformed to commercial sugarcane that virtually no natural habitats remain. It is not known whether this species occurs/ed in this area, but if it does it is quite likely very threatened.
South of Durban coastal development is causing ongoing, rapid declines in the habitat of coastal species such as Cyperus sensilis. |
Population |
Seven locations are known. In the St Lucia area, there are four locations, one within the St Lucia Wetland Park (a protected area), and plants also occur on four other properties of commercial forestry companies. Around Durban there are two known locations, one on a piece of natural vegetation in the middle of a racecourse, the other in a municipal park. Plants have also been recorded from Umdoni Park, where they are threatened and possibly already extinct due to coastal development. Locations are highly disjunct along the KwaZulu-Natal coast, and it is possible that other locations may exist. This species has been overlooked in Red Lists in the past.
The Cyperus sensilis hybrid, C. x turbatus, is found in disturbed wetland areas where road construction and excessive trampling have impeded drainage (Baijnath 1976). It is not certain whether this could indicate that C. sensilis is generally also tolerant of stagnant, degraded wetland habitats. C. sensilis has been recorded from the same sites as some known localities of C. x turbatus (Clairwood Race course, Umdoni Park). However, on the eastern shores of Lake St Lucia, where C. sensilis appears to be most common, wetland habitats are mostly pristine, so it cannot be assumed that the preferred habitat is degraded wetlands, although it may be tolerant of stagnation to a degree.
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Population trend | Decreasing |
Conservation |
| Protected in the Greater St Lucia Wetland Park. |
Notes |
| The collection records of this species indicate remarkable disjunctions along the KwaZulu-Natal coast - there is about 190 km between the St Lucia records and Durban and another 60 km between Durban and Umdoni Park. It can not necessarily be assumed that this species occurs nowhere in between these areas and that the localities known from herbarium records are the only existing localities. Coastal areas between Durban and St Lucia are however excessively transformed to commercial sugarcane (transformation = 74%, calculated using GIS), and between Durban and Port Shepstone coastal development is rapidly transforming coastal areas. If this species occurs in these areas, it is quite likely threatened and quite possibly not as common as the St Lucia area where the most extensive areas of suitable wetland habitat can be found. |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Cyperus sensilis Baijnath | NT B1ab(i,ii,iii,iv,v) | Raimondo et al. (2009) | |
Bibliography |
Baijnath, H. 1976. Studies in the Cyperaceae in Southern Africa: 8. Two new species of Cyperus L. Journal of South African Botany 42(4):369-375.
Baijnath, H. and Getliffe Norris, F. 1977. Studies in Cyperaceae in southern Africa: 9. Cyperus prolifer Lam. and some allied species. Journal of South African Botany 43(1):21-39.
Cook, C.D.K. 2004. Aquatic and wetland plants of southern Africa. Backhuys Publishers, Leiden, The Netherlands.
Raimondo, D., von Staden, L., Foden, W., Victor, J.E., Helme, N.A., Turner, R.C., Kamundi, D.A. and Manyama, P.A. 2009. Red List of South African Plants. Strelitzia 25. South African National Biodiversity Institute, Pretoria.
Sieben, E.J.J. 2009. The status and distribution of vascular plants (Magnoliophyta, Lycophyta, Pteridophyta). In: W.R.T. Darwall, K.G. Smith, D. Tweddle and P. Skelton (eds.), The status and distribution of freshwater biodiversity in southern Africa (pp. 83-98), IUCN and SAIAB, Gland, Switzerland and Grahamstown, South Africa.
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Citation |
| von Staden, L. 2007. Cyperus sensilis Baijnath. National Assessment: Red List of South African Plants version . Accessed on 2025/05/19 |
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