EPPO Global Database

EPPO Reporting Service no. 07 - 2012 Num. article: 2012/157

The economic cost of invasive alien species in Great Britain

The impact of invasive alien species can be manifold, ranging from loss of crops, damaged buildings, and additional production costs to the loss of livelihoods and ecosystem services. As detail in many cost estimates is lacking and as the impact on different sectors is largely unknown, research was carried out in Great Britain to estimate the current annual cost of invasive alien species (IAS) on the British economy. References related to over 500 non-native species were gathered from the scientific and grey literature as well as from the internet. A detailed questionnaire was sent to key organizations to gather initial information.

The total current annual cost of IAS to the British economy is estimated at 1 291 461 000 GBP in England, 244 736,000 in Scotland and 125;118 000 in Wales. The total annual cost of IAS to the British economy is therefore estimated to be approximately 1.7 billion GBP (2.16 billion EUR). Among all species groups, plants represent the highest annual costs with 483;030 000 GBP (approximately 612 600;000 EUR).

The annual costs of some individual invasive alien plants on the British economy had been estimated as follows:
Cost (in GBP)
in EUR
Fallopia japonica (Polygonaceae, EPPO List of IAP)
165;609 000
210 045 000
Hydrocotyle ranunculoides (Apiaceae, EPPO A2 List)
25;467 000
32;300 000
Rhododendron ponticum (Ericaceae)
8;621 000
10;900 000
Heracleum mantegazzianum (Apiaceae, EPPO List of IAP)
2;362 000
2 900 000
Impatiens glandulifera (Balsaminaceae, EPPO List of IAP)
1;000 000
1 300 000
Buddleia davidii (Scrophulariaceae, EPPO List of IAP)
961 000
1;200 000

Impacts and costs are estimated by sectors, some are detailed below:
Agriculture and horticulture: Bromus spp. and in particular Bromus sterilis (Asteraceae) are important weeds in British cereals and leguminous crops, causing cereal yield losses up to 45%. Avena fatua and Lolium perenne (Asteraceae) are also weeds in cereals, and Veronica persica (Plantaginaceae) is an important grain contaminant.
Forestry: Rhododendron ponticum (Ericaceae) is suspected to be present over 826 998 ha in Great Britain.
Tourism and recreation: the species considered to be a threat to fishing (angling) are Azolla filiculoides (Salviniaceae), Crassula helmsii (Crassulaceae, EPPO A2 List), Hydrocotyle ranunculoides, Elodea canadensis (Hydrocharitaceae), E. nuttallii (Hydrocharitaceae, EPPO List of IAP), Fallopia japonica, Lagarosiphon major (Hydrocharitaceae, EPPO List of IAP) and Myriophyllum aquaticum (Haloragaceae, EPPO List of IAP). The total annual cost estimate for angling is 1;365 084 GBP (1 700 000 EUR).
For recreational boating, expenditure is made for the control of H.;ranunculoides, H. mantegazzianum and I. glandulifera, as well as of Elodea spp., and Lagarosiphon major. The management of these aquatic species is estimated to amount to 29;862 650 GBP (37 800 000 EUR) annually.
Construction, development and infrastructure: the main species causing additional costs to the construction industry is F. japonica, and this species also reduces the value of housing and land for housing. Plants such as I. glandulifera and H. mantegazzianum cause delays to development projects. In addition, the total cost of B. davidii to infrastructures is estimated at 960 430 GBP (1;200;000 EUR).
Transport: F. japonica is a major concern for road management, as is H.;mantegazzianum, I. glandulifera and B. davidii.

This study demonstrated the benefits of intervention at an early stage, as well as long-term cost savings, if eradication is undertaken early in the invasion process.


Williams F, Eschen R, Harris A, Djeddour D, Pratt C, Shaw RS, Varia S, Lamontagne-Godwin J, Thomas SE, Murphy ST (2010) The economic cost of invasive non-native species on Great Britain. CABI, Wallingford (GB), 199 pp.