Research into IAS tends to focus on ecological aspects. However, the authors of this study argue that the social and economic aspects also need to be considered when designing strategies to tackle IAS. The study was based in the Doñana wetlands on the southwestern coast of Spain. The Doñana region plays a major role in wildlife conservation but is also used for agricultural purposes and tourism.
The survey questioned respondents about 15 non-native species including plants, invertebrates and vertebrates. A number of these have socio-economic benefits as well as negative environmental impacts. These included: the ice plant from South Africa, with uses in agricultural fields for soil fixation, but which competes aggressively with native species; eucalyptus trees from Australia, which are important to beekeepers and as a medicinal plant but which compete with native plants for water; and the red swamp crayfish, originating from North America, which is fished for food but can transmit disease to native species and degrade riverbanks through burrowing.
The survey was completed by five stakeholder groups in the Doñana region who were asked about perceived benefits of impacts of IAS and their willingness to pay for eradication measures. These groups were: local users (including farmers, fishermen and beekeepers), general tourists, 'nature tourists' and two groups of conservation professionals. Unlike previous surveys into perceptions of IAS, which have either questioned members of the public at random or a specific stakeholder group, this study deliberately compared a number of different stakeholder groups, each holding a different set of knowledge about IAS.
The results suggest that the more recently that the species was introduced, the more recognisable it is as a non-native species. Furthermore, different stakeholder groups were found to differ in their degree of knowledge, social perceptions, attitudes and willingness to pay for IAS eradication.
Income, age and distance of home from the Doñana region influenced how willing the respondents were to pay for eradication. For example, tourists from outside the area were more likely to pay than local users. Respondents who recognised the commercial benefits of IAS, such as crayfish fishermen or beekeepers, were the least likely to pay towards eradication. The results also indicate that respondents are more willing to pay for eradication of species with more general impacts on ecosystems, such as the water lettuce, and species which are less 'attractive', such as the Argentine ant.
Information campaigns highlighting the impacts of IAS that had been previously conducted in the Doñana region were found to have been successful, as respondents were more likely to recognise the subjects of these campaigns as invasive. Public information campaigns can therefore play an important role in supporting IAS management, the study suggests, and are key to the success or failure of IAS eradication projects. However, these should be targeted at specific stakeholder groups and take account of group interests, socio-demographic characteristics, environmental behaviour and personal experiences.