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Barry Commoner's Four Laws of Ecology, as written in The Closing Circle in 1971. PowerPoint Presentation
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Barry Commoner's Four Laws of Ecology, as written in The Closing Circle in 1971.

Barry Commoner's Four Laws of Ecology, as written in The Closing Circle in 1971.

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Barry Commoner's Four Laws of Ecology, as written in The Closing Circle in 1971.

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  1. Barry Commoner's Four Laws of Ecology, as written in The Closing Circle in 1971. 1. Everything is Connected to Everything Else. There is one ecosphere for all living organisms and what affects one, affects all. Consider- let’s remove the gray wolf from the Lamar Valley of the Greater Yellowstone Ecosystem…. Wait! We already did that in the 1800-1900’s!

  2. Okay fine, now what did the gray wolf normally eatin this ecosystem? X X X Human? Cow? Ok, a few Sheep? Once in a while Elk American Bison? Yah Baby! Moose?

  3. Okay, so what do Elk eat? Vegetation such as Aspen or Willow When the wolves were removed would you expect the number of Elk to increase or decrease? Duh! If the number of Elk increased, what would you expect to happen to the Aspen and Willow abundance?

  4. Freshly sprouted willow branches, healthy and un-browsed by elk A 1992 study in northern Yellowstone found that elk reduced potential willow seed production by 100% and that 47% of the willow communities had been height suppressed. Wolves were re-introduced into the area starting in 1995

  5. Photo taken 7/17/1997 Decadent (dying) Aspen in the northern Greater Yellowstone Ecosystem (northern range). All trees are 100-130 years old. No new growth since the root sprouts (ramets) have been completely eaten by Elk. (Page 66 in Yellowstone’s destabilized ecosystem by Frederic H. Wagner)

  6. Over browsed Aspen stand being replaced by sagebrush and related species (Photo from the Northwest Habitat Institute.)

  7. Aspen stands provide food or cover for literally hundreds (thousands) of other species, many of which have declining populations. For example, Red-naped Sapsucker MacGillivray’s Warbler Yellow Warbler CalliopeHummingbird Additional information about bird declines due to lack of wolf predation on large herbivores J. Berger, et al, 2001. Ecological Applications 11(4):947-960

  8. Back to willow- For the sake of discussion, does anything else eat willow plants? Beavers! So if the amount of available willow decreases, what would you expect to happen to the beaver population?

  9. Do Beaver have any effect on the environment? Does anything depend on the Beaver? So what was once a fast moving stream, is now a pond containing an entirely new ecosystem and supporting bank vegetation and creating flooded valleys which effect the water table.

  10. Barry Commoner's Four Laws of Ecology, as written in The Closing Circle in 1971. 2. Everything Must Go Somewhere. There is no "waste" in nature and there is no “away” to which things can be thrown. If willow and aspen communities are removed due to over browsing by Elk or Moose etc, and the beaver depart because of the lack of food/cover, can you predict what might happen to the stream banks and water table of the resulting ecosystem?

  11. Can you predict what kind of species would be able to use this ecosystem? What do you suppose would happen if land managers tried to re-introduce beaver into this system?

  12. Barry Commoner's Four Laws of Ecology, as written in The Closing Circle in 1971. 3. Nature Knows Best. Humankind has fashioned technology to improve upon nature, but such change in a natural system is “likely to be detrimental to that system.” So, what the heck, let’s just put the wolves back into the Greater Yellowstone Ecosystem? Hmmmmmm…… now there’san idea……. Stay tuned.

  13. Barry Commoner's Four Laws of Ecology, as written in The Closing Circle in 1971. 4. There Is No Such Thing as a Free Lunch. In nature, both sides of the equation must balance, for every gainthere is a cost, and all debts are eventually paid.

  14. West Virginia mountain forest view, original photograph by Jim Clark, Mountain Memories, Vandalia Press 2003

  15. A massive dragline, dwarfed by the huge scale of the operation, at work on a mountaintop removal surface mine operation near Kayford Mountain, West Virginia. Photo by Vivian Stockman, Oct. 19, 2003

  16. David Raup’s Corollary to Commoner’s Law