Chapter 17 Getting Practical about Introduced Species

Discussion Questions

1. Identify a nonnative species in your state or region that is widely perceived as beneficial. How was it introduced, from where, and how long ago? Now identify a nonnative species in your state or region that is widely recognized as damaging and destructive. How was it introduced, from where, and how long ago?
2. Suppose that 20 species were successfully established on an island, and 20 species were successfully established on a nearby mainland. What further information would you need to determine if the island is more invasible?
3. Suppose you had data recording the fate of introductions (naturalized or not? invasive or not?) on islands. What additional information or data would you want from those islands to test the biotic resistance versus biotic acceptance hypothesis?
4. What do you think is the path of introduction in your region for most nonnative terrestrial plant species? Insect species? Aquatic species?
5. Evaluate and compare the costs and benefits of control versus eradication of an invasive species that is known to be a problem in your region.
6. If humans value the presence of an introduced species of game fish, under what circumstances should efforts be made to eliminate the fish? Under what circumstances is it likely better to accept the continued presence of this nonnative species?

Group Projects

• Use the Global Invasive Species Database to generate a list of invasive species in your country or state. Select three species that are unfamiliar to you and then use your library and the Internet to locate ecological, economic, and possibly other studies examining these species. Rank the three species in terms of potential ecological harm and justify your ranking. Now rank the three species in terms of potential economic benefits, again justifying your ranking.
  
  
• The Australian Weed Risk Assessment is a questionnaire developed to screen out and prevent the importation of potentially troublesome plants. Develop a series of questions that could be used to decide whether a fish species is a high-risk import or presents relatively little ecological risk. Write between five and 10 questions with simple yes or no answers, and develop a scoring system that tallies the answers and yields a generalized “invasiveness risk” score. Provide the rationale underlying your scoring system.
  
  

Useful Websites

• Australian Weed Risk Assessment is a questionnaire-based process designed to assess the potential weediness of a plant species before it is allowed to enter Australia. http://www.agriculture.gov.au/ba/reviews/weeds


• Global Invasive Species Database was developed as part of the global initiative on invasive species led by the Global Invasive Species Programme (GISP). It provides global information on invasive alien species and covers all taxonomic groups from microorganisms to animals and plants. http://www.issg.org/database/welcome


• Invasive.org provides a database of invasive species that focuses on weeds, pests, and diseases but also includes links to dozens of other invasive species databases. http://www.invasive.org


• Invasive Species Specialist Group provides technical and policy advice to manage the risk of biological invasions. This IUCN group also shares information regarding invasive species via the Global Invasive Species Database. http://www.issg.org/

Suggested Readings for In-class Discussion

• Davis MA, Chew MK, Hobbs RJ, Lugo AE, Ewel JJ, et al. (2011) Don't judge species on their origins. Nature 474: 153-154.
  
  
• Murcia C, Aronson J, Kattan GH, Moreno-Mateos D, Dixon K, Simberloff D (2014) A critique of the ‘novel ecosystem’ concept. Trends Ecol Evol 29: 548-553.
  
  
• Norton DA (2009) Species invasions and the limits to restoration: Learning from the New Zealand experience. Science 325: 569-571.
  
  
• Seddon PJ, Griffiths CJ, Soorae PS, Armstrong DP (2014) Reversing defaunation: Restoring species in a changing world. Science 345: 406-412. (And response: Ricciardi A, Simberloff D (2014) Fauna in decline: First do no harm. Science 345: 884.)
  
  
• Simberloff D, Vitule JR (2014) A call for an end to calls for the end of invasion biology. Oikos 123: 408-414.