Oregon Public Broadcasting

A study of Olympic National Park suggests the elimination of wolves 70 years ago has dramatically altered the park ecosystem.

Larger elk herds triggered landscape transformation.

The Oregon State University researchers take no position on whether wolves should be reintroduced into this part of the Northwest.  Correspondent Tom Banse has more.

Two forestry researchers measured tree growth patterns and re-read historical journals to see whether Olympic National Park is as pristine as it seems.  Bounty hunters and trappers exterminated the area’s last wolves in the 1930’s.

Oregon State professor Bill Ripple says removal of the top predator set off an ecological cascade.

Bill Ripple: “That increased elk foraging in the streamside areas.”

Thickets of trees and shrubs in the flood plain decreased.

Bill Ripple: “And then we think that ecological cascade continued on to the shape of the streams.  It increased erosion and the streams widened as another result. And this has implications for fisheries and fish habitat.”

Federal biologists who work in Olympic National Park say the Oregon researchers overstate the impact of wolves, especially when you get down to river shapes.

A rebuttal paper is in the works.  Returning wolves to Olympic National Park was discussed in the late 1990’s, but died for lack of support in Congress.

Oregon State University report - .pdf