They suck up millions of gallons of water, further endanger already threatened or endangered species, cost billions of dollars, undermine agriculture, affect waterways and land from plains to forests, ruin ecosystems by crowding out native species, and breed like crazy.

Invasive species swim, grow, crawl, have plagued western states for decades, affect about 100 million acres or the size of California, and breed like crazy.

And they must be stopped, the Western Governors’ Association announced Thursday.

The association published the first-ever list of the 50 worst invasive species — 25 terrestrial and 25 aquatic — affecting the west. (full article)