Article by Douglas Fox
Discussion Questions
1. Are fenced landscapes fragmented habitats? How do they differ from other anthropogenic features that fragment habitat (e.g., roads, agriculture)? Are fences uniformly resistant to wildlife, or are they more permeable for some species than others? Which species in the article may be more affected by fences, and which kinds of fences may be more or less permeable?
2. How did the fence of Addo influence elephant biology? Did it cause inbreeding? What morphological characteristics of elephants were used to assess inbreeding and ecological effects? Did the fence affect behavior? Relate these stories about the Addo fence and elephants to what you know about population ecology.
3. The United States has been constructing a fence on the Mexican border to control illegal human immigration. How do you think this fence will affect ecosystems? Are there any wide-ranging species shared among the bordering states in the U.S. and Mexico? Might any endangered species be affected?
4. What technological processes are outlined in the article as means of making fences more effective for target species and less for non-target wildlife? What is RFID? To what distances is RFID effective? How was it developed? What about biological fences? What are some of the advantages and potential drawbacks of each of these approaches?
5. How can knowledge of ecology and animal behavior help with the construction of fences? Why is it important to engage biologists when planning such fences?
6. Back in the 1970’s and ‘80’s, environmental activists in the American West would routinely cut barbed wire fences (illegally) to help restore wildlife population connectivity. What do you think of this behavior?
7. Fences are sometimes used in a positive sense to enhance wildlife migration. In what circumstances would one want to use fences to direct movements away from potential hazards?
Websites for Further Information
• Legal case about the environmental effects of the U.S. border fence (pdf)
• Wildlife Fencing Guidelines from the Wyoming Game and Fish Department: http://gf.state.wy.us/downloads/pdf/habitat/Bulletin%20No.%2053.pdf
• National Geographic special on pronghorn migration: http://news.nationalgeographic.com/news/2009/08/090813-pronghorn-migration-missions-video-wc.html
Wildlife and Fences in the News
• Immigration fence seen as a deadend for wildlife (MSNBC, May 21, 2007): http://www.msnbc.msn.com/id/18788333/
• Pronghorn get free rein on the prairie (The Globe and Mail, August 19, 2009): http://www.theglobeandmail.com/news/national/pronghorns-get-free-rein-on-the-prairie/article1253962/
Peer-reviewed Literature (in addition to citations listed in the article)
• Clevenger, A.P., B. Chruszcz, and K.E. Gunson 2001. Highway mitigation fencing reduces wildlife-vehicle collisions. Wildlife Society Bulletin 29: 646-653.
• Thouless, C.R., and J. Sakwa. 1995. Shocking elephants: fences and crop raiders in Laikipia District, Kenya. Biological Conservation 72: 99-107
Key Concepts
• Animal migration and dispersal
• Conflicts between wildlife conservation and agriculture
• Applied ecology
