When wolves were reintroduced to Yellowstone, no one anticipated how much they would change the landscape. It seems as though nearly all of the changes link back to the fact that deer and elk behave differently when wolves are around. They graze in smaller herds, and move more frequently. They’re harder for humans to kill, because they’re more watchful and live in smaller herds. And they browse less intensively, allowing cottonwood and aspen groves to replenish themselves for the first time since the 1920s when the wolves disappeared.
(I edited this wolf photo from this website, and the guy that posted it thought it was probably a remote camera photo).
Wolves hunt along the waterways, and so grazers no longer browse along the water’s edge. The big winner in this reorganized ecosystem is the beaver. Beavers have a long childhood: they live at home for two summers, and the third summer they move out and build their own dam and lodge. That summer when they’re three years old is the most vulnerable time in their life. They have to hide in streamside burrows until their new ponds fill in and their lodge is built. Where the streamside vegetation is sparse, they are killed.
When wolves were returned to Yellowstone’s Northern Range, the thicker riparian edge provided good hiding space for the three-year-old beavers, and the beaver population increased by 9 times in a decade. Nine times. If you want more beaver in the landscape, just add wolves.
Ranchers talk about the expense of wolf predation, and hunters dislike having warier prey. But in the arid West, one thing that everyone agrees on is that more water is a good thing. Wolves make the deer and elk nervous, it’s true, but more beaver means more wetlands, and more wetlands means a lusher landscape with more prey. Surprisingly, wolves (and the beavers that followed) brought more bird species, and denser bird populations, more butterflies and of course more soil moisture downstream. It is a strange fact that the same people who want wolves removed from the Western woods like water more than anything.
The very same people.
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