Saturday, January 16, 2010

A Lesson in Ecology

Lately, I've been thinking about the first law of ecology which states: everything is connected to everything else. Last week I stood in the Hayden Valley watching the Canyon wolf pack feed on a carcass. They had pulled a piece of winter-killed bison calf (winter kill is when an animal succumbs to some other ailment such as hunger, weakness, or injury and dies on its own) aside and the alpha female and male were eating while the big, black alpha male slept in the sun nearby. As soon as the two wolves moved off to nap the ravens descended. Later, when the wolves moved further away I'm sure the coyotes in the valley came to scavenge as well. Eagles and magpies may join them. Not mention a host of beetles and bugs that will finish the process. All the result of one bison calf dying—and that's only the beginning.

In the years since the 1995 wolf reintroduction there have been a number of ecological changes in Yellowstone that scientists are studying to determine the relationship between the changes and the wolves. Having wolves as predators appears to change where elk graze. Now elk stay out of streambeds because they are vulnerable to attack there. Willows are recovering in Yellowstone. With the growth of willows there has been an increase in beaver (who have been at low numbers). Because of the dams beavers build wet, riparian areas are increasing. With more marshy areas the moose population may rise, not to mention amphibians and song birds. The wolf return means fewer coyotes. Fewer coyotes likely result in more fox, more rodents, and more pronghorn antelope fawns survival. More rodents mean more owls, hawks, and eagles.

Sometimes the interrelationships tell a sad story. Trumpeter swans are recovering from near extinction in the middle of the past century. Hundreds of swans migrate from Canada to winter in and around Yellowstone. They come because thermal runoff into rivers keeps the water from freezing. Swans used to fly further south, but they have lost wetlands along the way. They migrate by memory and now that no swans know the way the restoration of wetlands will not restore their previous migration. Should Yellowstone have a hard, cold winter many will starve to death and threaten the existence of the year-round swan population in the area. I wonder how they lost their wetlands. Was it in the building of houses, suburbs, and cities? I like to believe that if a few ponds and marshes were preserved along the way that human society would reap as many benefits from them as the swans would. I believe that unintended consequences matter. Sometimes they matter most.

Garrett Hardin expressed the first law of ecology in these words, "We can never merely do one thing." Although humans have a tendency to view themselves as separate from nature, this first law applies just as it does to wolves, ravens, and swans. Each choice and decision has multiple effects, many of which are unexpected.


Sometimes, the end of a long day finds me driving through the woods watching the last rays of sun filter through the trees casting long shadows on the snow. I think about relationships. I chose to come to Yellowstone to guide and drive. I knew I would learn some mechanical skills and facts about the Park. I didn't fully realize the way the friends I make here would change my perspective. Or that being here would clarify my expectations of work that I would like to pursue. I value relationships with friends and family so much more.  Priorities are different.  I hadn't expected to learn about faith, trust, and patience. I am learning a bit more about prayer and to search and work for answers.  As the sun slips behind the horizon I conclude that human life is as complexly woven as the natural environment that surrounds me.

All things by immortal power.
Near of far, to each other linked are,
that thou canst not stir a flower
without troubling of a star.
- Francis Thompson (English poet 1859-1907)



Sources: Decade of the Wolf by Douglas W. Smith & Gary Ferguson, http://www.trumpeterswansociety.org/swan-migration-project.html

3 comments:

Jacque said...

Another beautiful treescape photo!

Unknown said...

I seem to remember that the Trumpeter Swans used to also winter in the reserve around Willard Bay until it was seriously compromised in a drought around 10 years ago. I have a book about it that was recommended to me in the environment classes I was taking.

jonny said...

How true that it seems to be the unintended consequences that matter most. Thanks for that thoughtful reminder.