Hitched to the Universe
“When we try to pick out anything by itself, we find it hitched to everything else in the Universe.”
–John Muir
We have heard the warnings all our lives: the industrial activities, and simply the sheer burden of the number of people on the planet are greatly altering our environment. Hollywood has made millions upon millions of dollars, illustrating the dire consequences to be played out over the succeeding decades and centuries. But, sometimes people get it right – they make changes that benefit the ecosystem. Think about the ban on DDT, and the reversal of reproduction fortunes for peregrine falcons and eagles. Or the efforts to ban lead ammunition in California to support the recovery of the condor. Simply removing hunting allows animals to move back into their natural ranges and expand their population, such as the sea otter.
So today’s news says that research shows that grizzly bears are healthier in Yellowstone due to the reintroduction of wolves. Turns out, there were just too many elk browsing on plants and reducing the availability of plants for grizzly food. (Yes, grizzlies eat a great amount of berries, and only an occasional tourist or Boy Scout.) So, when you add the wolves back in, who help keep the elk population in check, it benefits the bears.
Now, there may seem to some contradictory findings, as the bears were also eating elk, and there was some concern about the elk populations. But, by adding the wolves back into the ecosystem, the berry-bearing bushes and shrubs are recovering, and the bears are enjoying this fruity harvest. And, the wolves have increased the complexity, and hence the stability, of the ecosystem.
Some may think that wolves and grizzly bears are dangerous and should be “controlled.” After all, we haven’t had a grizzly in California since 1922 (except on the state flag). And, we haven’t had a wolf in California since 1924…until recently. In late 2011, a lone wolf wandered over the border from Oregon to check out the real estate. While these big predators can be intimidating, as general rule, humans are not on their preferred menus. But, their presence signals a more balanced and healthy ecosystem, which in the end, is good for humans, too.
Read more:
Yellowstone grizzlies put on the pounds, thanks in part to wolves
And for you science nerds, here is the link to the journal article:
Journal of Animal Ecology: Trophic cascades from wolves to grizzly bears in Yellowstone