Education of Biology Group

Monday, April 6, 2009

E-Book #7:Frontiers Issues to Teach Ecology

Surprises and lessons from the 1988 Yellowstone fires

Monica G Turner1, William H Romme2, and Daniel B Tinker3
The size and severity of the fires in Yellowstone National Park in 1988 surprised ecologists and managers alike. Much has been learned about the causes and consequences of crown fires from studies of the Yellowstone fires, and some results were surprising. Plant cover in burned areas was restored rapidly by native species, making post-fire rehabilitation generally unnecessary and possibly even counterproductive. While 20th-century fire suppression has affected systems like Yellowstone far less than other ecosystems, managing forests, people, and property in wildfire areas is an ongoing challenge. Insights gained and lessons learned from the Yellowstone fires may be applied elsewhere and can help inform fire policy.




Landscape Ecology of Large, Infrequent Fires in Yellowstone Park

Authored and edited by Charlene D'Avanzo, School of Natural Sciences, Hampshire College, Amherst, MA, 01002 cdavanzo@hampshire.edu

ARTICLE:
Turner, M.G., W.H. Romme, and D.B. Tinker. 2003. Surprises and lessons from the 1988 Yellowstone fires. Frontiers in Ecology and the Environment. 1 (7): 351-358.

ECOLOGICAL CONTENT:
landscape ecology, Yellowstone National Park, fire ecology, patch, disturbance, succession, regeneration, lodgepole pine

TEACHING FOCUS:
Landscape ecology is a relatively new aspect of ecology, and the first author of this paper, Monica Turner, is one of its strong proponents. This would be a good paper for discussion about what landscape ecology is and why it is interesting. The 1988 Yellowstone Fire made headline news and so the topic would draw in students. By working with the figures in this paper students will come to understand how fires produce a mosaic of plant communities and how different plants respond to fire. The Scientific


E-Book #6:TEACHING ISSUES AND EXPERIMENTS IN ECOLOGY

Title
When Biocontrol Isn’t Effective: Making Predictions and Understanding Consequences

ABSTRACT PAGE

The Issue
Invasive species cause significant ecological and economic harm, and therefore effective management strategies are of utmost importance. One common yet controversial method proposed to control invasive plant species is biological control. This issue explores how relatively short-term ecological research can be combined with matrix modeling to evaluate the likely success of biological control. Students will incorporate actual research data into a modeling program to determine the effects of biocontrol on the population growth rate of an invasive species. Further, they will explore the consequences of introducing an actual biological control agent and discuss the associated risks and benefits. This issue, particularly Figure Set 2, is most appropriate for use in an upper-level ecology or population ecology course.

Ecological Content
biological control, demography, herbivory, indirect effects, invasive species, matrix modeling, population ecology, plant tolerance, trophic cascades

Student-active Approaches
think-pair-share, jigsaw

Student Assessments
essay quiz, one minute paper, concept map

Authors
Michele R. Schutzenhofer1 and Tiffany M. Knight2 Washington University in St. Louis, St. Louis, MO 63130

1- mrschutzenhofer@mckendree.edu
2- tknight@biology2.wustl.edu

Acknowledgements
The authors would like to thank E.A. Pardini and the students in the Population Ecology course at Washington University in St. Louis for encouraging the continued development of this activity and Washington University and the National Research Initiative of the USDA Cooperative State Research, Education and Extension Service, grant number #05-2290, for financial support.
Citation Schutzenhofer, M. R. and T. M. Knight. February 2009, posting date. When Biocontrol Isn’t Effective: Making Predictions and Understanding Consequences.

Teaching Issues and Experiments in Ecology, Vol. 6: Issues
Figure Set #1 [online]. http://tiee.ecoed.net/vol/v6/issues/figure_sets/biocontrol /abstract.html



FIGURE SET HEADER for Set #1

Figure Set 1: What are the effects of herbivory on individual plant survival and growth?

Purpose: To interpret graphical results and to examine how herbivory affects individual plant survival and growth.
Teaching Approach: Think-pair-share
Cognitive Skills: (see Bloom's Taxonomy) -- Knowledge, Comprehension
Student Assessment: One minute paper

BACKGROUND for Set #1 (back1.html)

Invasive species are species that have been introduced from their native range into an area where they do not have an evolutionary history. Further, invasive species are categorized as highly problematic species, causing both economic and ecological harm (Pimentel et al 2005). There are numerous invasive plant species that have been introduced to the United States that are problematic and need to be managed, including bush honeysuckle (Lonicera maackii), garlic mustard (Alliaria petiolata), and spotted knapweed (Centaurea maculosa). Typical management strategies often include hand-pulling, mowing, chemical spray, or a combination thereof. For some species, these management strategies can be an effective means to reduce the abundance of invasive species, ultimately reducing the negative effects they have on native species and communities. In other cases, typical management strategies are not enough to reduce invasive species’ abundance or are too costly to employ. When such traditional management techniques prove inadequate (based on cost or effectiveness), biological control is often considered a feasible alternative. In plants, for instance, biological control consists of introducing enemies (herbivores), often referred to as biological control agents, from the plant’s native range. The herbivores are meant to “damage” the invasive plant species by consuming plant tissue, reducing plant resources, and therefore curbing its population growth.

One invasive species that is considered highly problematic is Lespedeza cuneata (common name: sericea lespedeza or Chinese lespedeza). Lespedeza cuneata is a perennial legume native to eastern Asia. It was introduced in to the United States in the 1930s to stabilize areas that had been strip mined. It was also recommended the Department of Transportation in many states to use for quickly stabilizing roadsides. While the plant grows quickly in poor soil and requires little maintenance, it is those same traits that also make it an invasive threat. Lespedeza cuneata does not stay put. From the initial plantings, L. cuneata has spread by the movement of animals, hay, and equipment used to cut hay, and through the blowing wind. It can now be found throughout the eastern and Midwestern United States. It encroaches on our native prairies, savannas, glades, woodlands and forests. Normal grassland management practices such as grazing and burning do not adequately control L. cuneata and can actually increase its spread.

Lespedeza cuneata produces prolific amounts of seed, and some of that seed can remain dormant in the soil and germinate at a later time, making it very difficult to eradicate the species once it establishes. Further, L. cuneata makes two different types of seeds: cleistogamous seeds



FIGURE SET HEADER for Set #2

Figure Set 2: What are the effects of herbivory on population growth rate?

Purpose: To understand how a demographic matrix model works using a modeling program (R). To use demographic modeling to calculate population growth rate for control plants and then modify the model to understand how herbivory treatments change the results. Students will find that individual level consequences (examined in figure set 1) do not always translate into population level consequences. Students will then calculate an elasticity matrix to understand that not all vital rates contribute equally to the population growth rate.

Teaching Approach: Think-pair-share
Cognitive Skills: (see Bloom's Taxonomy) -- Knowledge, Comprehension, Interpretation Student Assessment: essay quiz

BACKGROUND for Set #2 (back2.html)



FIGURE SET HEADER for Set #3

Figure Set 3: Indirect effects of biological control of knapweed.

Purpose: To allow students to teach each other about the cascading effects resulting from an introduced biological control agent, involving the invasive knapweed, the biological control agent (gall flies), mice, and hantavirus.

Teaching Approach: Jigsaw
Cognitive Skills: (see Bloom's Taxonomy) — Comprehension, Interpretation, Synthesis
Student Assessment: essay quiz, concept map

BACKGROUND for Set #3 (back3.html)

Background

For Instructor and Students

E-Book #5TEACHING ISSUES AND EXPERIMENTS IN ECOLOGY

Title: Of wolves, elk and willows: how predation structures ecosystems

ABSTRACT PAGE

The Issue
Elimination of top predators (e.g. wolves) from regions like the Greater Yellowstone Ecosystem leads to changes in prey population density and behavior, as well as overall community structure. This issue addresses how ecosystems change when predators are removed, and what happens in such a system when the predators are restored. It is designed to address students’ misconception that predators only influence ecosystems directly through predation. In the Greater Yellowstone Ecosystem, wolves exert impacts not only on their prey (elk) but also on lower trophic levels (e.g. willows).

Ecological Content
predation, trophic cascades, keystone species, direct vs. indirect effects, top-down vs. bottom-up effects, predator control, predation risk, prey behavior

Student-active Approaches
pairs share, hypothesis development, informal group work

Student Assessments
formulate hypotheses, essay quiz, minute paper, and concept map

Author
Cynthia Dott Department of Biology, Fort Lewis College, Durango, CO 81301 Dott_C@fortlewis.edu



FIGURE SET HEADER for Set #1

Figure Set 1: Changes in cottonwood and willow abundance in the 20th century.

Purpose: To practice interpreting graphical data; to use the data to generate hypotheses about what could have caused a decline in cottonwood and willow recruitment.
Teaching Approach: “Pairs share” and hypothesis development
Cognitive Skills: (see Bloom's Taxonomy) knowledge, comprehension, interpretation, analysis Student Assessment: generate hypotheses

BACKGROUND for Set #1 (back1.html)

Background

Where have the cottonwoods and willows gone?



FIGURE SET HEADER for Set #2

Figure Set 2: Factors influencing suppression and recrutiment of woody riparian vegetation.

Purpose: To practice interpreting graphical data; to use the data to accept or reject hypotheses about potential causes of cottonwood and willow decline; to refine and revise a hypothesis based on new data.
Teaching Approach: “pairs share” and report out
Cognitive Skills: (see Bloom's Taxonomy) – knowledge, comprehension, interpretation, analysis Student Assessment: essay quiz or minute paper

BACKGROUND for Set #2 (back2.html)

Background

What factors could influence suppression and recruitment of woody riparian vegetation?

FREE DOWNLOAD

FIGURE SET 3 FIGURE SET HEADER for Set #3

Figure Set 3: Causes of intense elk browsing on cottonwoods and willows during the 20th century.

Purpose: To practice interpreting graphical data; to use the data to address the question of why browsing by elk in Yellowstone was so intense during the 20th century.
Teaching Approach: “pairs share”
Cognitive Skills: (see Bloom's Taxonomy) -- knowledge, comprehension, interpretation
Student Assessment: minute paper or essay quiz

BACKGROUND for Set #3 (back3.html)

Background

Why was elk browsing on cottonwoods and willows so intense during much of the 20th century?

FREE DOWNLOAD


FIGURE SET 4 FIGURE SET HEADER for Set #4

Figure Set 4: How do wolves impact elk and elk browsing, if not by direct population control?

Purpose: To introduce the idea of indirect effects of predator on prey by changing prey behavior, and of trophic cascades – effects of predators on primary producers; to construct a flow diagram of effect of prey behavioral response to predation on vegetation; to use concept mapping to construct a complex food web for the Greater Yellowstone Ecosystem.

Teaching Approach: informal group work
Cognitive Skills: (see Bloom's Taxonomy) -- knowledge, comprehension, interpretation, application, synthesis
Student Assessment: flow diagram and (optional) concept map

BACKGROUND for Set #4 (back4.html)

Background

How do wolves impact elk and elk browsing, if not by direct population control?