SOUTH LAKE TAHOE (AP) — Researchers at Lake Tahoe are raising new concerns about nonnative, warm-water fish invading the mountain lake's chilly waters, including giant, minnow-gulping goldfish weighing as much as 4 pounds. Studies in the mid-2000s prompted funding for a warm-water fish control program at the University of Nevada, Reno. Since the project began in 2011, scientists have removed thousands of fish, including about 90 goldfish, mostly on the south end of the lake around the Tahoe Keys.