invasive species

The teams in the project will develop recommendations for a large-scale strategy to manage invasive species.

The volunteer day is one of the rehabilitation efforts along the 13 miles of the North Platte River that runs through Casper.

The boat from Canada was last in the water on the St. Lawrence River two years ago.

Cheatgrass currently grows on about 40 square miles of the forest and is spreading at a rate of about 20 percent a year.

The historic stocking of nonnative fish nearly eliminated westslope cutthroat trout and fluvial arctic grayling from Yellowstone.

That could mean more giant rangeland wildfires that in recent decades destroyed vast areas of sagebrush country that support some 350 species of wildlife, including imperiled sage grouse.

Starting this year, only rubber boots will be allowed in Yellowstone because felt sole boots are virtually impossible to cleanse of mussels.

The Western Governors' Association published the first-ever list of the 50 worst invasive species -- 25 terrestrial and 25 aquatic -- affecting the west.

The boating season will run from May 26 through Nov. 4.

If nonnative mussels are detected in Yellowstone, a closure to all watercraft (except authorized National Park Service boats) would occur to prevent the spread to other waterways.