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Extensive testing for the presence of the parasite in wild trout populations all across the state. To date, we have sampled only a small percent of the state's salmonid habitats, but have tested all of the state's major trout fisheries. Our goal is to have statistically valid samples completed on all Colorado streams by 1999. To date, all major trout streams and most large cold- and coolwater impoundments have been tested. Areas still needing testing are largely confined to small streams and remote high mountain lakes. 2. Monitoring the level of virulence and infectivity of the disease in most major streams in the state that are currently affected at the population level (loss of year classes), including, but not limited to, the Arkansas, Big Thompson, Blue, Cache la Poudre, Colorado, Dolores, Fryingpan, Gunnison, Rio Grande, Roaring Fork, South Fork of the Rio Grande, South Platte, and Taylor rivers. Susceptibility testing of many strains and species of salmonids to determine their vulnerability to the WD pathogen, including brown trout, brook trout, A+ Colorado River cutthroat trout, Trappers Lake cutthroat trout, Colorado River rainbow trout, and Tasmanian rainbow trout. This effort will be continued in 1996 and will include tests on the Rio Grande and greenback cutthroat trout and the Snake River cutthroat trout, along with other salmonids. 4. Annual population-level monitoring as to the status of wild rainbow and brown trout populations in the streams in 42 (above) to assess whether or not there is a change in the effects of WD on wild salmonid populations. 5. Collection and testing of Colorado River cutthroat trout populations from 17 streams on the west slope during 1995. Encouragingly, all populations tested negative for WD. This effort is being continued and expanded in 1996. 6. Conducting a research project to answer the question of whether the continued stocking of trout from WD+ units into WD+ habitats increases or maintains WD spore levels above that produced by the alternative tubifex worm host. 7. Collection and preservation of aquatic oligochaete worms from the same streams where Colorado River cutthroat trout were captured and tested in 1995 to determine if the alternate host of the pathogen occurs in cutthroat trout habitats. We recommend that DOW biologists cooperate and share knowledge with other scientists and agencies involved in WD research. If this is done, everyone will benefit. As the magazine Fisheries recently noted, "A coordinated approach to investigating whirling disease across the country would shorten the learning curve, thereby benefitting public resource stewards and the private sector. It is time to search for answers and knowledge, not scapegoats." (Hulbert 1996). 9