FISH PASSAGE AT ROAD CROSSINGS IN A MONTANA WATERSHED

A basin-wide assessment of fish passage through culverts was performed in the upper Seeley Lake watershed in western Montana. The watershed has many small streams that support a variety of trout species, predominately cutthroat trout and brook trout, but with some bull trout and brown trout too. A total of 47 culverts were studied, and at these culverts the FishXing model and a screening tool that is a composite of several flowchart-based models were used to predict fish passage success. At a subset of 21 culverts, fish were collected above and below the culvert to check for population differences with respect to species, size, and abundance. At another subset of 10 culverts, fish passage was directly assessed using fish traps. Results indicate that the FishXing model and the composite screen are conservative estimators of fish passage in culverts. The direct passage assessment indicated that more fish passage occurred during low flow than was expected, and the population (above/below) sampling results gave little evidence to indicate that many of the culverts were functioning as barriers to fish passage. However, there was evidence that fish passage was restricted at many of the culverts at low flow. High flow was not examined in detail at the field sites in this study.

Language

  • English

Media Info

  • Features: Appendices; Figures; References; Tables;
  • Pagination: 39 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00987640
  • Record Type: Publication
  • Report/Paper Numbers: FHWA/MT-05-002/8160,, Final Report
  • Contract Numbers: MSU G&C #Z2491/426249
  • Files: TRIS, USDOT, STATEDOT
  • Created Date: Mar 7 2005 12:00AM