Implications for Policy and Research

There has been no prior synthesis of pathway information, impacts, or human management of introductions for alien reptiles and amphibians. Yet those data are of critical importance for informing future management and research decisions with respect to these animals. They are especially important inasmuch as the mod ern flood of invasive species represents one of our greatest conservation challenges. So what general patterns and conclusions emerge from the data provided in the previous chapters?

We have seen that a wide array of pathways has been involved in herpetological introductions, but that six of these have been dominant, even though their impor tance varies taxonomically, temporally, and geographically. In addition to these, four minor pathways contributed lesser numbers of introductions to the total. We have seen that several of these major and minor pathways revolve around similar, unifying themes: an aesthetic nexus that promotes the keeping of animals and their frequent escape, release, or introduction via private owners, wholesalers, retailers, exhibitors, or zoo personnel, and a trade-goods nexus that transports animals in cargo or vehicles as unintentional hitch-hikers in the course of regional or interna tional trade activities. The patterns of taxonomic, temporal, and geographic varia tion seen in pathway importance allow scope to investigate whether ecological and economic parameters might serve to predict variation in naturalization and invasion success. Although that work is not begun in the present work, one study demon strates the importance of climate, propagule pressure, and phylogenetic propinquity in predicting establishment success among alien reptiles and amphibians (Bomford et al., 2005, in press). Examination of a wider array of ecological attributes seems likely to improve predictive success in this regard, which would be useful for screening proposed deliberate introductions for likely invasiveness.