The goal of this project is to develop consistent and comprehensive statewide fish distribution data for all salmonid species at a scale of 1:24,000. This distribution data will represent the known or probable presence of all salmonid species throughout the state of Oregon. Known distribution supported by recorded observation data will be distinguished from information that has no supportive observation data (referred to as probable presence information). Probable presence information will be categorized according to the level of confidence of the biologist providing the information. Where available, and as time permits, information will be captured to describe the level of confidence that a particular species does not occur in a given area. However, no attempt will be made to verify species absence.

For anadromous salmonids, distribution will be identified by habitat use-type (spawning and rearing, rearing and migration, or migration only). Resident salmonids will be noted as present - no attempt will be made to distinguish the use of the habitat involved, unless migration corridors are a critical feature of the species’ life history.

Fish distribution occurring on streams contained within the 1:100,000 routed stream layer will be displayed as continuous lines on the stream line-work by habitat use-type or presence category. Distribution occurring on 1:24,000 scale streams will be displayed as points on the stream and will represent use-type transition points along a stream, with the furthest upstream point also representing the upper extent of fish distribution. These data points can be used to create continuous lines when a 1:24,000 routed stream layer becomes available.

The results of this project will be fully compatible with current efforts to develop 1:24,000 stream coverages. It is anticipated that once the 1:24,000 stream coverages are available for entire 4^th field HUCs, information resulting from this proposal will be incorporated onto the new 1:24,000 map layers as lines rather than points. Until that time, information from both scales will be combined and overlaid onto digital topographic map images called digital raster graphics (DRGs). Upon completion of the project, ODFW will conduct a one-day workshop for all potential end users (e.g., ODEQ, ODF, ODFW, Watershed Councils) to describe the data and demonstrate appropriate uses, along with training on how to access the database.

The source for determining the distribution for all streams indicated to have species presence will also be recorded. ODFW District staff, along with biological staff from other cooperating agencies will be asked to assist with identifying physical observation data as their schedules permit and this information will be recorded as it is made available. Either physical observations or the professional judgment of staff biologists will be considered viable documentation and distribution will be recorded based on either source. In some instances, professional judgment of assisting biologists from differing agencies will not match. Project staff will arbitrate these cases according to established guidelines until a final decision is reached.

Observation data will be categorized based on the specificity of the location information provided (i.e. stream name, stream length along a stream, exact pool location, etc.). Observation data that cannot be linked to a single stream will not be utilized (i.e. a juvenile trap at the mouth of a subbasin). Observation data used to verify fish distribution will be obtained and forwarded to the StreamNet Library in Portland where it can be made available if direct access to the source data is needed.

Ancillary attribute information will also be captured which will enhance the utility of the fish distribution information. This will include information on the existence of barriers to upstream migration of adult fish. Migration barriers will be categorized according to their influence on the fish (total or partial barrier), by species. Also, information on timing of occurrence by life-stage (spawning, rearing, migration) and genetic and production origin (wild, hatchery - how did the species come to be there originally, and how is it being sustained presently) will be compiled at the 4^th, 5^th, or 6^th field hydrologic unit (HUC) scale depending on the precision of available information.

During the scope of this project, all attributes will be maintained and updated as new information become available. However, once established, distribution information will not be changed or modified without credible proof that a change is necessary. This will prevent the need to re-visit with every area biologist each time a modification is proposed.

At present, most information related to fish distribution is located at individual ODFW field offices as well as several other natural resource agency offices, making it difficult to determine where the various species and their habitat occur within watersheds. This effort will bring together information from various sources into a single database. Existing information will be used as the starting point for making updates. This will ensure that past efforts are not wasted or duplicated. This effort will also ensure that new information is compatible with existing ODFW fish distribution data layers by using established criteria and definitions.

1. 1: