Two recent news stories about wildlife management in the Sierra Nevada remind us of how deeply we humans affect what we like to think of as the “natural” world. We are, it seems, involved in pretty much everything that goes on around us.
The first story comes out of UC Santa Cruz, where research fellow Jack Hopkins has recently published the results of a study that documents shifting patterns in black bear feeding habits in Yosemite.
As anyone who spends time in the Sierra knows, American black bears happily seek out and consume food brought into the mountains for human use. Some bears become highly dependent upon human foods, which are rich in calories and often all-too-easy to obtain.
This dependence (almost an addiction) can result in extensive property damage in campgrounds, and “offending” bears often become aggressive and must be destroyed. You’re all familiar with stories of raiding campground bears and the havoc they sometimes create.
For several decades, national park managers at Yosemite have worked diligently to turn this situation around. Similar work has occurred locally at Sequoia and Kings Canyon. The key, the managers realized, was that human behavior had to change. Only when campers and other visitors to the mountains realized that bears must be denied access to human food would the situation improve.
Out of this came the modern world of “bear-proof” garbage cans and food-storage lockers in campgrounds coupled with education and also with fines for people who ignored the rules and continued to allow bears to obtain human food.
Campers have sometimes chafed against all this, but now we have proof that it has made matters better. According to the UC Santa Cruz study, the percentage of human food in bear diets in Yosemite has now dropped by almost two-thirds as compared to 1975-1985.
The result, of course, is that bears eating more natural diets interact less often with visitors, do less damage to human property, and – most importantly – live longer and more natural lives.
The second story – still developing actually – has to do with Sierra Bighorn sheep.
The Sierra Nevada contains many thousands of black bears but only a few hundred bighorn sheep. Sheep numbers were once much higher, but populations crashed in the late nineteenth century in response to the introduction into the mountains of domestic sheep and diseases they carried. As a result, wild sheep came very close to extinction.
Seeking to increase wild sheep numbers, wildlife managers in recent decades have worked to protect the handful of existing herds. At the same time they have done their best to encourage these herds to grow so that they could then capture “surplus” animals and release them in other places that had once supported sheep populations. This has now been done successfully several times, including in the Tioga Pass area along the eastern boundary of Yosemite National Park.
Here in the southern Sierra, wild sheep occupy the rugged Sierra Crest region that marks the eastern boundary of Tulare County. Two small herds persist in the vicinities of Mt. Williamson and Mt. Langley. Now, we have a third herd.
Within the past several weeks, California Department of Fish and Game officials have cooperated with National Park Service staff to reintroduce bighorn sheep into the Big Arroyo region east of Mineral King. Brought in by helicopter, ten ewes (females) and four rams (males) now occupy the area. The fourteen sheep came from Wheeler Ridge northwest of Bishop and Sawmill Pass near Independence.
Those who know our local mountains will recognize that the Big Arroyo is in the wilderness heart of Sequoia National Park and about as far removed from civilization as one can get these days. The hope, of course, is that in this remote region the sheep will reproduce and prosper.
As I remarked at the beginning of today’s column, both of these stories serve to remind us of the inescapable role we humans play these days in most everything.
We have profoundly affected bears by making human food available to them, a change that not only corrupted many wild bruins but also often led to their premature deaths. Now we know that we must discipline ourselves if we are to live successfully with these intelligent and highly adaptable animals.
As for wild sheep, we almost lost them altogether because we prized domestic sheep grazing above the needs of wildlife. We reduced sheep numbers so severely that without our help their very survival fell into doubt. Now, seeking to reverse this grim pattern, we are investing significant money in an attempt to return wild sheep to our local mountains
As is so often the case, we humans have the capacity for both good and evil. Today, at least when it comes to wildlife, it’s nice to be able to report two successes.
© Wm. Tweed