Soft touch or heavy hand? Legislative approaches for preventing invasions: insights from cacti in South Africa
Format Extent863234 bytes
MetadataShow full item record
The rate of transportation, introduction, dissemination and spread of non-native species is increasing despite growing global awareness of the extent and impact of biological invasions. Effective policies are needed to prevent an increase in the significant negative impacts caused by invasive species. Here we explore this issue in the context of the history of invasion and subsequent regulation of cacti introduced to South Africa. We considered seven approaches to restricting trade—by banning: (1) species already invasive in the region; (2) species invasive anywhere in the world; (3) species invasive anywhere in the world with a climate similar to the target region; (4) genera containing invasive species; (5) growth forms associated with invasiveness; (6) cacti with seed characteristics associated with invasiveness; and (7) the whole family. We evaluate each approach on the basis of the availability/complexity of information required for implementation including the cost of the research needed to acquire such information; the likely numbers of false positives and false negatives; the likely degree of public acceptance; and the costs of implementation. Following a consultative process, we provide recommendations for how to regulate non-native cacti in South Africa. The simplest option would be to ban all cacti, but available evidence suggests that most species pose little or no risk of becoming invasive, making this option unreasonable. The other extreme—reactively regulating species once they are invasive—would incur significant control costs, likely result in significant environmental and economic impacts, and limit management goals. We recommended an intermediate option—the banning of all genera containing invasive species. This recommendation has been partly incorporated in South African regulations. Our study emphasizes the importance of scientific research, a legal framework, and participation of stakeholders in assessments. This approach builds awareness, trust, and support, and ensures that all interests are reflected in final regulations, making them easier to implement and enforce.