Invasive Species

Our understanding of most of the current environmental issues facing us would probably be improved with a stronger understanding of basic ecology. Environmental issues, such as invasive species, provide opportunities to apply what we have learned in an applied context.

Invasive species can have profound effects on an environment. Because the resident species have had no evolutionary history with the invader it is possible that the resident species are highly susceptible to the negative effects of an invader (e.g., they have no defenses agaist a predator or a disease). Last summer I saw first hand how evolutionary history can influence interactions bewteen species. The Galapagos Islands are so isolated from continental South America that no large predators have been able to colonize the archipelago. Thus, when we would go hiking on the Galapagos Islands, the birds and animals living there literally showed no fear so that we were able to approach them very closely (I used to be impressed at all of the amazing photos I have seen of birds on the Galapagos Islands, but now I know that the photographer was only two feet away). Imagine what would have happened had a predator been introduced; the fearless animals would have been easy prey to an exotic predator.

Further Info

1) Here is a link to a presentation that I made for my seminar on the Rio Grande River. It provides general information about invasive species, how species can harm communities, and efforts that people have used to try to control invasive species. It also discusses some examples of species that have invaded Texas.

http://www.slideshare.net/secret/bL1TCLiLtoH5Np

2) Here is a link to a presentation that I made for my seminar on the Rio Grande River discussing the invasive tree, tamarisk (Salt Cedar). Tamarisk is an important invasive species in riparian areas of the western US and has become an important environmental issue in the region. There is a lot more detail in this presentation than you need to worry about.

http://www.slideshare.net/secret/CxG30GwOj6yRr7


Expected Learning Outcomes

At the end of this course a fully engaged student should be able to

- discuss the variety of mechanism through which novel species are introduced into a community (TEKS 112.43. 12B & 12E and TEKS 112.44. 4C, 4D, & 4E)

- identity examples of introduced species in your own area

- identify examples where introduced species have caused economic and environmental damage to an ecosystem (TEKS 112.43. 12B & 12E and TEKS 112.44. 4C, 4D, & 4E)

- explain why introduced species might often have large negative effects in communities (TEKS 112.43. 12B & 12E and TEKS 112.44. 4C, 4D, & 4E)

- discuss potential ways to limit invasions or to remove novel species (TEKS 112.43. 12B & 12E and TEKS 112.44. 4C, 4D, & 4E)