PROJECT LEADER:
Mary Hanson, Bull Trout Coordinator, ODFW, 503-872-5252, ext. 5602, mary.l.hanson@state.or.us

PROJECT PURPOSE: Display current and historic (pre-1990) distribution of bull trout in Oregon (and in adjacent states where metapopulations overlap); for use with the 1997 statewide status report on bull trout, conservation strategies, and for general distribution.

COVERAGES: Coverages were created using ArcInfo software. ODFW uses the Lambert modified projection. The basic stream coverage is the USGS 1:100,000 layer. In several instances it was necessary to import stream layers using the 1:24,000 layer available from the US Forest Service or hand digitize using a USGS 7.5 quad map for guidance to adequately depict streams with bull trout not shown on the 1:100,000 layer.

Bulldist2000 is a line coverage displaying statewide bull trout distributions updated to include data collected through 1999 by state, federal and tribal fishery biologists. The item 'Bulltr' can be sorted for four categories (also displayed in hard copy version): 1) Spawning, rearing, or resident bull trout, 2) Historic Distribution (pre-1990), 3) Migrating bull trout, and 4) Probably Extirpated. There are also some segments with a 0 category, which has no significance for bull trout. Please remember that these distributions are where we have documentation of bull trout presence. Most surveys are done during the summer and fall months. Wintertime distributions could vary significantly from summer/fall locations, but we have very little data statewide to portray an accurate picture of winter distribution for bull trout. We do not consider these coverages complete as we continue to look for bull trout in potential habitat across their range and we likewise lack extensive information on winter habitat.

Additional categories have been added to the distribution coverage to start recording 1) spawning and resident rearing areas, 2) juvenile (0 - 2+) rearing areas different from 1, and 3) subadult (2+ to adult) rearing areas. These categories are incomplete and should not be used without consulting with Mary first.

A point coverage (Bullpoint2000) showing bull trout sighting information is also available at the ftp site. It is a partial record of a variety of surveys and miscellaneous observations of bull trout. Sighting (y,n) indicates whether bull trout were encountered at a particular site; Yrsight is the year the sighting occurred; Traptype, Trapnum are fields that indicate if a fish was captured in a trap, the trap type and a number if one exists; Yearfrom and Yearlast refer to trap operation periods; Statrpt refers to whether the point was included in the 1997 Oregon Bull Trout Status Report; Comment and Comment2 are for additional comments; Ahuc and Stream are geographic references; Method is how the fish was observed, whether it was captured in a trap, angled, observed during a survey, was an historic observation, electrofished, or tracked using radio telemetry; Revised indicates the year the coverage was updated; and Location is for indicating that the location is confirmed or not. A "n" indicates the location is provisional pending review by the source. A "y" indicates provisional location of a point has been confirmed. Absence of a "y" or "n" should not be interpreted as an unconfirmed location. The sources of the data are the same as for the line coverage.

UPDATES: The database will be updated as new information becomes available at least through July 2001. Coverages on the FTP site will be updated annually. Users of these coverages should check with Mary on any current updates to the coverages not reflected in the current version on the FTP site. Hard copy maps are plotted on an as needed basis and reflect the latest information. Future updates will be completed subject to available funding.