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Study Says Loss of Wolves Damaging Olympic National Park's Forest Ecosystem


An over-abundance of elk is damaging the rainforest ecosystem of Olympic National Park, according to an Oregon State University study. OSU photo.

To many, the heart and soul of Olympic National Park is the temperate rainforest. There so much moisture falls that places such as the Hoh Rainforest and the Queets valley feel spongy, the air heavy with humidity.

Indeed, when the park was set aside in 1938, it was done so "to preserve the finest sample of primeval forests in the entire United States."

But there's trouble in this paradise, according to a study from Oregon State University. The loss of wolves from the park's ecosystem is causing a decline in those forests, for the predators are not around to keep Olympic's elk herds in check. As a result, the ungulates are over-grazing the forests.

This recently released study maintains that "the extermination of wolves in the early 1900s set off a 'trophic cascade' of changes that appear to have affected forest vegetation and stream dynamics, with possible impacts on everything from fisheries to birds and insects."

Published in the journal Ecohydrology, the report cites information gathered by the Press Expedition during its exploration of the Olympic peninsula in 1890. That expedition found the banks of the upper Quinault River “so dense with underbrush as to be almost impenetrable,” according to the OSU report. "Logs jammed the rivers, dense tree canopies shaded and cooled the streams, and trout and salmon thrived along with hundreds of species of plants and animals."

Such a scene is hard, if not impossible, to find today.

“Today, you go through the same area and instead of dense vegetation that you have to fight through, it’s a park-like stand of predominantly big trees,” says Bill Ripple, a co-author of the study and forestry professor at Oregon State University. “It’s just a different world.”

Elk, he says, are transforming Olympic's landscape as streamside ecosystems are losing young trees to the voracious animals.

Compounding the problem of wolf eradication was the creation of the national park in that it offered protection to the elk from hunters. As a result, their numbers soared and vegetation tumbled.

“Our study shows that there has been almost no recruitment of new cottonwood and bigleaf maple trees since the wolves disappeared, and also likely impacts on streamside shrubs, which are very important for river stability,” said Robert Beschta, lead author of the study and professor emeritus of forest hydrology at OSU. “Decreases in woody plant communities allow river banks to rapidly erode and river channels to widen.

“Tree and shrub species along stream banks and floodplains started crashing first,” Professor Beschta explains. “Then, apparently, the rivers began to unravel. Now we have large areas where the forest understory vegetation is mostly just grasses and ferns.”

The report notes that streams that once flowed in tight channels held in check by thick vegetation have broadened and become braided. Too, the scientists note that the water is open to the warming sun and less enriched by plants and insects. Nearly half of the terraces along the Queets River have disappeared because of accelerated erosion over a period of multiple decades.

“We’ve seen the impact of wolves on the ecosystem in Yellowstone, the effect of cougars in Yosemite National Park, the same basic story about the importance of key predators being played out in many different places,” Professor Ripple says. “What’s so surprising here is that it’s happening in a temperate rainforest, which is hugely productive and has such high levels of vegetation growth. But even there, when the ecosystem gets overwhelmed with many large herbivores, the vegetation just can’t keep up.”

An effort was considered to restore wolves to the park ecosystem in recent years, but no decision or actions have been undertaken to accomplish that.


Replace wolves with controlled hunting.

Need a better predator/pray balance...not control hunting! Keep the damn hunters and ranchers out of the equation and let nature do it's job.

Both of the comments do hold important issues in preserving the ecosystem. There are times that both are needed to bring an deterorating ecosystem back into check. Hunting by it's self isn't the answer, you need the balance of predator/prey to keep things under control after the ecosystem has been restored. The process of restoring the wolf population is only part of the equation, you will need to replant loss vegation along river/creeks bed to stop the erosion, and be able to manage those areas to ensure future growth and stability.

As I understand it, Olympic Nat'l. Park is pretty remote. That being the case, maybe some of the ranchers near Yellowstone could be mollified by transporting some wolves to your neck of the woods. Lots of places, livestock owners don't like the wolves, I know the actual numbers prove them wrong, and so do you, but it's still a tough sell.

Carry on, then.

Controlled hunting or "culling" of animals doesn't work. That was proven in Yellowstone, where elk numbers were kept artificially low for years through "culling". Yet the aspen, cottonwoods, beaver, songbirds, willows etc. did not make a comeback until the wolves were returned. Even when elk numbers were lower than they are now. Why? Because it is not just elk numbers, it is elk HABITS. Habits are not changed by human hunting or culling, they are changed by the constant threat of an apex predator. In fact this is a complaint that many hunters have about wolves. The elk no longer hang out in river bottoms munching willows and aspen shoots. They sneak in at night and then scatter. They are constantly on the move. Wild elk again instead of cattle waiting to be "culled". My guess is that, given half a chance, wolves will return on their own; but if not, reintroduction certainly should be considered.

Hunters with firearms are the main control on Olympic Peninsula elk-populations today. Hunters - both local rural folk and veritable hordes in pickup campers 'from the cities' - lobby heavily to manage the herds at the highest achievable levels - the better to successfully hunt them.

Present limits on the carrying capacity for elk are set primarily by the amount of clearcut logging being done outside the Park on public & private timberlands. Elk - as browsers - do best where most of the growth is in the form of brush and herbage. Once trees begin to dominate a site, they shade out such growth and the area offers insufficient food for them.

These are, bear in mind, Roosevelt Elk, bigger than typical North American Wapiti, and they travel, live & feed in large herds. Many dozens ... even hundreds in the old days when they had access to extensive forest fire regeneration areas. The limited size of today's clearcuts, may in turn be limiting the size of the herds we see.

Kurt, it is my understanding that originally, President Theodore Roosevelt set aside the Olympic Mountains (about 30 years before it was made a Park) explicitly as a refuge for the summer calving grounds of the elk herds. The herds head above the timberline for the meadows, as directly & early as the melting snowpack allows. Further, the really desirable forest stands were in the lowlands outside the rugged terrain of the Olympic Mountains ... and both Roosevelts failed to preserve those forests and have been criticized for demurring to timber and State economic interests. By the time Franklin made the Park, the big lowland trees - the real forest treasure that would have astounded people today (I've lived with the stumps all my life...) were gone.

There are good studies showing dramatic elk increase following large fires of the past (The Forks Burn, 1952, perhaps 50 square miles), and hunters today head directly for clearcut regions (in the lowlands) that have had a few years to 'jungle out', and the elk have learned where they are, but not enough time for tree-regeneration to start killing off the browse.

Wolves would be expected to drive the elk from low-quality understory where they might now be loitering in the fall within the Park (to avoid the hunters, possibly). Such 'elk parks' are a known habit of the herds, and they do chew-up & trample such sites rather noticeably. They shelter from hard weather and chew their cud within such open-understory, closed-canopy timber ... and will nibble on what little brush grows there, easily overpowering its ability to regrow. But that's just part of being elk ... and possibly avoiding the dominant predator today. [close to Franks' comment..]

The basic 'problem' with the idea to reintroducing wolves in the Olympics, is that they are expected to follow the herds out of the Park in the fall, as the elk return to the lowland wintering grounds, where they will compete directly with firmly entrenched & highly organized hunters. The assessment of the Park's wolf carrying capacity was about 50 animals. Their assessment-descriptor did not include the private & commercial timberlands, making key parts of the wolf-proposal a wink & blink game.

Small numbers of wolves have been moving into various parts of the region surrounding the Olympic Peninsula. Since these wolves are not generally being hunted or trapped, it is reasonable that a pack may establish on the Peninsula by it's own devices. This could be a considerably more interesting & valuable process to observe, than another head-butting contest by opposing human groups.

hunters need to stay the hell away and it would all be fine

the hunters need to stay away and the wolfs need a reservation to keep pochers away

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