Invasive species monitoring, South West England

The brief

Thomson Ecology was commissioned by Teignbridge Borough Council, as part of the Southwest Strategic Coastal Monitoring Programme, to map four invasive non-native plant species and two further non-native plant species identified at 23 sites. This covered over 24 km2 of coastal habitats found within Dorset, Devon, Cornwall and the Isles of Scilly.

The target invasive species were Himalayan balsam (Impatiens glandulifera), Hottentot fig (Carpobrotus edulis), Japanese rose (Rosa rugosa) and montbretia (Crocosmia x crocosmiiflora), and two other species – Karo (Pittosporum crassifolium) and Tresco rhodostachys (Ochagavia carnea).

What we did

The principal approach was to use recent aerial imagery to identify and map the target species present in the area of interest.

An experienced ecologist within the geospatial team took the lead on processing the aerial imagery data, mapping the extent of the target species into an ArcGIS geodatabase and writing up the final report detailing our methodology, results and the legal status of the invasive non-native species identified in this study.

From inspection of the aerial imagery and photographs collected as part of an earlier study, non-native plant species were identified as being present at 11 of the 23 sites studied.

The outcome

The written report along with GIS data was supplied to the client. Subsequently the report has been circulated amongst the Southwest Strategic Coastal Monitoring Programme partners and other interested parties.