ECOLOGICAL RESTORATION READINGS: FREEMAN, 2005 Chapter 54 Pages 1277-1283

ECOLOGICAL RESTORATION

READINGS:FREEMAN, 2005

Chapter 54Pages 1277-1283

What is restoration ecology?

• It is the application of ecological principles to return populations, species or communities (ecosystems) to their natural state.

• The act of restoration covers a wide range of problems to be solved and practices to be used.

Restoration of Populations or Species

• When a local population or entire species is showing signs of progressive decline, then the act of restoration is best described as recovery.

• When a local population or a large number of populations have become extinct, restoration requires reintroduction.

Reintroduction of Populations

• The reintroduction of a population to an area where it was once known to occur requires more knowledge and effort than the act of recovery.

• Two of the problems to be solved are: * where to get the plants or animals to be introduced? * where to find the most suitable habitat for introduction?

Recovery of a Population

• One of the unfortunate lessons learned by conservation biologists is that protection of plant and animal populations by establishing preserves is only a first step for many populations.

• Increasing the size of a declining or small population requires a good deal of knowledge about the biology of the species.

Recovery Studies: Doing Some Science

• Even in the highest quality preserves, some species may not be maintaining stationary or growing populations.

• Even populations that are stationary may be small thus at high risk for extinction.

• Determining best practices for recovery efforts requires “doing some science.”

Recovery Study: Site

• Wolf Road Prairie is a 80 acre nature preserve of which approximately 40 acres is managed as prairie and savanna. Remainder is marsh and shrub dominated “prairie”.

• Largest remnant of high-quality tallgrass prairie on silt-loam soil in Illinois.

• 327 native taxa have been recorded as being present in the area since 1973.

Recovery Study: Observations

• It is common practice to sow seeds of the plant species as the major attempt at recovery.

• It is possible to transplant adult plants as a means of promoting recovery.

• Little is known about the relative success of the seeding versus transplant methods for promoting recovery of a plant species in a prairie remnant.

Recovery Study: Experimental Subject

• Great St. John’s Wort is a perennial forb that has a complex life history.

• Only 1 plant was known to exist at Wolf Road Prairie in 1991; making it a good subject for a recovery project.

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• Great St. John’s Wort is much less common in Illinois than in Wisconsin.

• Its relative rarity and fidelity to native plant associations give it the highest conservation value (10).












These are the various stages in the reproductive life of Great St. John’s Wort (Hyparicum pyramidatum).

Life History Stages of Great St. John’s Wort

Recovery Study: Question

Which life history stage of Great St. John’s Wort is likely to have the highest survivorship during the early years of a recovery project?

Question: Which life history stage of Great St. John’s Wort is likely to have the highest survivorship during a recovery project?

Hypothesis: Transplants of adult plants are more likely to survive than juvenile plants or seedlings arising from stratified seeds.

Null Hypothesis: Survivorship of all life history stages will be equal throughout the recovery project.

Experimental Setup: Establish all three life history stages of Great St. John’s Wort in the UIC Greenhouse. Take to randomly selected sites at WRP and transplant or sow seeds. Record number of plants surviving for several growing season.

Results:

• Conclusion: Recovery of Great St. John’s Wort is best using vegetative stage year old plants.



How effective is seeding as a recovery method?

• Of the nearly 4 million seeds sown at WRP, only 30 adult flowering plants were known to be produced.

• Odds of getting from seed to flower were about a million to one.

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Number of Seeds

118575 163998345391

760500

998000

416667 358333

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Year Seeds Harvested

1993 1994 1995 1996 1997 1998 1999 2000

Seeds Sown at Wolf Road Prairie

Great St John's Wort

Restoration of Communities (Ecosystems)

• The task of restoring communities (ecosystems) is even more complex than the task of recovery since the goal is to enhance the survival of a larger number of species.

• At UIC, we recognize three different levels of community restoration.

Enhancement

• This level of activity focuses on only a few native species that may require efforts at recovery or reintroduction.

• Ecosystem level management techniques place primacy on fire.

• An example is found at Woodworth Prairie. Visit: http://www.uic.edu/depts/bios/prairie/

Revitalization• Focuses on a larger number of species

and modifications of the physical environment.

• Native species are augmented by plants and seeds from native plant gardens.

• Non-native species are targeted for removal by cutting or herbiciding.

• Fire is used as a management tool.• An example is Wolf Road Prairie. Visit: http://www.savetheprairiesociety.org/

Reconstruction• Works with land where native communities

have been replaced by non-native species.• Efforts to reintroduce a large number of native

species and control populations of non-native species.

• In addition to using fire, herbicides, mowing, and cutting, hydrology returned to original conditions.

• An example: Schulenberg Prairie. Visit: http://chicagowildernessmag.org/issues/summer2000/schulenberg.html

ECOLOGICAL RESTORATION

READINGS:FREEMAN, 2005

Chapter 54Pages 1277-1283

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ECOLOGICAL RESTORATION READINGS: FREEMAN, 2005 Chapter 54 Pages 1277-1283