SEATTLE - A water-loving rodent native to South America that has destroyed thousands of acres of wetlands in the southeast has been spotted near Lake Washington. Nutria are semi-aquatic, chocolate-colored rodents that can weigh more than 20 pounds and eat one-quarter of their weight a day in crops and plants of all varieties. Also called coypu, or swamp rats, they burrow through marshes and levies, and females can produce more than a dozen offspring a year. A trapper recently caught nine along the shores of Lake Washington. Two University of Washington students are studying the rodents to determine where they...