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Scientific Name | Lumnitzera racemosa Willd. var. racemosa |
Higher Classification | Dicotyledons |
Family | COMBRETACEAE |
Common Names | Tonga Mangrove (e) |
National Status |
Status and Criteria | Endangered* B1ab(ii,iii,v)+2ab(ii,iii,v) |
Assessment Date | 2017/01/18 |
Assessor(s) | A. Rajkaran, J. Adams & D. van der Colff |
Justification | The species is assessed as Least Concern at the global scale, however it is experiencing population decline across its global distribution due to coastal development (Ellison et al. 2010). In South Africa at the regional level, this species is only known from a single location and it has a EOO and AOO <1 km ² with continuous decline as a result of harvesting. The intense pressure coming from harvesting has resulted in a decline in the population in the Kosi Bay area and the species is assessed as Critically Endangered, however because this is a regional assessment and the species is wide spread outside of the assessment area and also experiencing declines, based on IUCN regional assessment guideline, a regional assessment adjustment is required, and here we have adjusted the status to Endangered at the regional level. |
Distribution |
Endemism | Not endemic to South Africa |
Provincial distribution | KwaZulu-Natal |
Range | Occurs only in Kosi Bay. A globally widespread species also occurring from Kenya to South Africa, Madagascar, tropical Asia, Northern Australia and Polynesia. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Mangrove Forest |
Description | Mangrove swamps, usually on the landward side. |
Threats |
| The species occurs in the upper drier parts of the Kosi Bay estuary which makes the species more accessible to harvesters, branches are harvest most likely for firewood. These branches that are harvested result in a change in the growth form of the plant, this impacts on the reproductive output of the species by reducing resource allocation to reproduction (A. Rajkaran, pers. Comm. 2016). As a higher ratio of adults to seedlings have been recorded in a recent study by Rajkaran (2011). |
Population |
This species has a widespread global distribution, however its South African population is considered to be isolated from the neighbouring Maputo Bay population as few propagules are received, however this has not been quantified but based on propagule size and distance (±100 km) to travel to Kosi Bay; it is expected to be low (A. Rajkaran, pers. Comm. 2016). The potential recruitment in the Kosi Bay population from Maputo Bay is projected to be much lower than recruitment within the population.
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Population trend | Decreasing |
Citation |
| Rajkaran, A., Adams, J. & van der Colff, D. 2017. Lumnitzera racemosa Willd. var. racemosa. National Assessment: Red List of South African Plants version 2017.1. Accessed on 2019/12/11 |
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