In the wolf hearings Fish and Game held around the state, one of wolf advocates most powerful arguments for keeping the wolf population high was their assertion that it would have a positive cascading effect throughout the ecosystem.
Their argument, based on the research of two Oregon State ecologists released in 2003, is that fear of wolves is keeping elk from eating too many young trees and shrubs in the streamside zones along rivers. Robert Beschta and William Ripple , professors of forestry at Oregon State say the reintroduction of wolves has allowed willows and cottonwoods to grow back, reducing erosion, improving stream quality and encouraging the return of species from insects up to birds.
The two OSU scientists research fits the view that restoring wolves has reduced the overgrazing that was going on in the park because the elk populations were allowed to grow largely unimpeded, a view livestock growers and range managers shared for years.
Don Despain, a retired plant ecologist with the U.S. Geological Survey, who has studied Yellowstone since 1971, has been telling me ever since their report came out in 2003 that he doesn’t believe wolves are the reason willows and other streamside shrubs are growing back. He and Yellowstone researcher Ron Renkin say longer growing seasons, caused by climate change, are the cause. There is a good story about this at High Country News.
Which scientists are right? Probably both. But it will take more research to determine whether climate change or wolves are having the larger impact.
Nothing is simple in ecology.
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Wolf populations important
A few weeks ago there was an article that talked about the number of people who hunt decreasing every year. Only a handful of people hunt now, even in Idaho, and in the not-so-distant future there may not be any significant number of hunters left. Seems to me that we will need to keep a healthy population of wolves and other predators to help balance the ungulate population.
More complex
Rocky Barber, you make it sound like scientists are in the "either or" camp on this issue. When reading the HCN article it is clear that the scientific community believes that the issue is much more complex and likely a combination of the wolf reintroduction and climate change.
Either/or?
I agree its complex. Despain is clearly a bottom up guy. For him it starts in the soil. But he says ecosystems are multi dimensional and small changes can make a big difference.
It does what it likes...
whether you understand or not. Whether or not can cause the changes as is claimed in this magnatude, nature can still take us out of the picture. We can be extinct too.
Wolves &Willows
In the area near the conluence of Soda Butte Creek and the Lamar River in Yellowstone, it is obvious that wolves play a very important part in willow and aspen regrowth.
Elk that show up along the streambanks in this area get killed or pursued by wolves. Before the wolves were reintroduced in the park, I would see elk all over along both streams when I visited. Today, the elk hurry through these areas and those that linger soon have wolves on their trail.
During a visit this fall, I photographed members of the Druid Pack feeding on an elk they had just killed in the Lamar River at the confluence. Thanks to wolves, the willows get taller every year.
He's correct in that aspect...
They can chew trees silly.
The positive impact
I'm glad someone acknowledges there is a good side to wolves. I'm interested to see if someone makes the wolf/willow tree/more oxygen/less "global warming" connection.
I'm beginning to wonder...
if 25% of that was only human's hot air but really ;-0
Interesting theory
I think you are on to something :p
I think...
I probably produce some myself : )