The local and state transportation agencies are developing an inventory of the culverts and their conditions. Species Interactions Salmon have survived major climatic and geologic changes over the past 5,000 years because of their genetic diversity. Scientists have identified characteristics of salmon that vary for each tributary. When hatchery stocks are introduced to streams, the spawning may produce future generations without the characteristics needed for that particular stream. There has been no analysis of the earlier releases, but approximately 440,000 live fish or eggs have been released into Johnson Creek since 1978.
Fishing is another species interaction.
Overharvesting can reduce the number of salmon as well as genetic diversity. No records exist of the harvest of salmon from Johnson Creek, or through their migratory route. In 1998 the Oregon Department of Fish and Wildlife discontinued stocking the creek with legal-size rainbow trout, which will reduce the incidental harvest of salmon. Efforts in our watershed Laws and regulations are the primary means of protecting Johnson Creek and other watersheds from the impacts of human activities. There is broad water quality legislation like the Clean Water Act, and there are more specific regulations directed to agriculture, industry, construction, wetlands, water diversions, and stormwater discharge.