Recently, the Virginia Department of Game and Inland Fisheries (VDGIF) joined the more enlightened states in publishing good quality GIS information on wild trout. Trout streams that support natural trout reproduction are classified on a 4-level scale (defined below the picture) as follows:
Sources: Virginia Department of Game and Inland Fisheries (VDGIF), Google Earth
Class i (cyan). Stream of outstanding natural beauty possessing wilderness or at least remote characteristics, an abundance of large deep pools, and excellent fish cover. Substrate is variable with an abundance of coarse gravel and rubble. Stream contains a good population of wild trout or has the potential for such. Would be considered an exceptional wild trout stream.
Class ii (blue). Stream contains a good wild trout population or the potential for one but is lacking in aesthetic quality, productivity, and/or in some structural characteristic. Stream maintains good water quality and temperature, maintains at least a fair summer flow, and adjacent land is not extensively developed. Stream would be considered a good wild trout stream and would represent a major portion of Virginia’s wild trout waters.
Class iii (green). Stream which contains a fair population of wild trout with carrying capacity depressed by natural factors or more commonly man-related landuse practices. Land use activities may result in heavy siltation of the stream, destruction of banks and fish cover, water quality degradation, increased water temperature, etc. Most streams would be considered to be in the active state of degradation or recovery from degradation. Alteration in landuse practices would generally improve carrying capacity of the stream.
Class iv (purple). Stream which contains an adequately reproducing wild trout population but has severely reduced summer flow characteristics. Fish are trapped in isolated pools where they are highly susceptible to predators and fishermen. Such streams could quickly be over-exploited and, therefore, provide difficult management problems.
On the “VA Resources” menu, you can find links to download this information to set up your own workstation. The “VA Quickstart Tutorial” explains how, designed for folks who know how to use Google Earth. Persons who are not experienced Google Earth users may want to download and work through a detailed tutorial on setting up Google Earth which can be found on any of the GIS Tools pages.