Invasive plant species are a major global threat and islands like St Helena are particularly vulnerable to the introduction and establishment of non-native plant species. Due to St Helena's unique native biodiversity, invasive plant species can have devastating effects on the environment.
Since the completion of the Airport construction, several plant species previously not known to St Helena have been recorded. One plant species in particular was observed at several locations. Initially, due to the plant's similarity to some of the native species, the identification proved difficult. However, the plants were later positively identified as the Namibian Ice Plant (Galenia populosa) (see poster attached).
It is thought these plants were introduced to the Island through river sand imported from Namibia during the Airport construction. Since April 2017, continual monitoring and surveys have been conducted by the Agriculture & Natural Resources Division (ANRD), Environmental Management Division (EMD), Landscape & Ecology Mitigation Project (LEMP) and the Invasive Plant team.
Invasive Plant Specialist, Ludi Kern, explains:
From the current data, it is clear that there is a significant increase in the number of plants since first observed. The highest number of plants are usually observed during the rainy season.
Regular surveys are conducted at previously reported sites and people working in these areas are encouraged to report any new plants found. Identification of additional sites relies heavily on the public and their observations. There is a possibility that the river sand was transported to other areas of the Island by persons who bought or used it. If the public is aware of any sand being used outside of the Airport, we encourage you to inform the Invasive Plant Team.
Should the ice plants continue to spread, it could negatively affect our native habitat. To prevent this spread, we need to act now. Whilst Galenia populations are still relatively small and isolated, their effective dispersal mechanisms, fast growth and adaptation to dry harsh conditions increase their chances to become a serious invader if not managed.
If you have seen any of these plants then please contact the Invasive Plant Team via the below details:
Email: email@example.com Tel: 24724 or 66463Email: firstname.lastname@example.org Tel: 22224 or 67142
Messages can also be sent to the team via their dedicated Facebook page: https://www.facebook.com/WeedbustersStHelena/ Please send a description of the area the plants were observed (or GPS location) and if possible take a photo of the plant. It is important not to remove the plants.
A species alert has been posted on the Project Facebook page and is also attached to this press release.
Source: St Helena Government