Bull Trout
            NE Studies
            Hood River
            Upper Klamath
       Redband Trout
            Great Basin
            Klamath Basin
            Blitzen River
            Malheur River
       Cutthroat Trout
            Miller Lake
       Oregon Chub
       Sand Roller
       Tui Chub
       Speckled Dace
       Borax Chub
       Warner Sucker
       Goose Lake Fishes






Pacific and Western Brook Lamprey

Spawning Western Brook Lamprey Coastal Oregon populations of Pacific lamprey Lampetra tridentata and western brook lamprey L. richardsoni are considered depressed due to habitat loss and passage problems (Close et al. 2002, Nawa 2003, ODFW 2006). Dam counts at Winchester, Bonneville, and Leaburg dams show a dramatic decrease from historical levels (Kostow 2002, Nawa 2003, ODFW 2006). In 2003, eleven environmental groups petitioned the U.S. Fish and Wildlife Service to list Pacific, western brook, river and Kern brook lamprey as endangered in the Pacific Northwest and California (Nawa 2003). Even though the petition cited multiple reasons for habitat loss, the U.S. Fish and Wildlife Service determined the petition did not contain adequate information to warrant a listing (Federal Register, 69 (27 December 2004) 77158-77167). The Oregon Department of Fish and Wildlife recently reviewed the status of western brook and Pacific lamprey and found populations to be ‘at risk’ of extinction (ODFW 2006) due to habitat loss, passage barriers and pollution. However data necessary to conduct a thorough and detailed assessment are lacking.

Much of the data lacking are critical to the effective management and conservation of Oregon’s coastal lamprey species. The Columbia River Basin Lamprey Technical Workgroup (CRBLTW 2005) and members of Columbia River Inter-Tribal Fish Commission (CRITFC 2004) have identified and prioritized critical data gaps for Pacific lamprey, many of which also apply to western brook lamprey. Among these are 1) methods to assess distribution and abundance of all life stages and appropriate techniques for monitoring population status; 2) population structure and delineation; 3) population dynamics; 4) basic biology including interspecific and community level relationships; 5) limiting factors and threats including passage issues, and 6) habitat needs and requirements.

Spawning Distribution and Habitat Associations

In 2004 and 2005 the Native Fish Investigation Project conducted a study to identify habitat Pacific Lamprey Redd variables associated with spawning Pacific and western brook lamprey in order to infer distribution throughout coastal Oregon. The objectives of this study were to

    1) Determine distribution of spawning Pacific and western brook lamprey in the Smith River basin;

    2) Describe redds of both species; and

    3) Describe associations of spawning Pacific and western brook lamprey in relation to habitat unit and reach scale habitat characteristics.

In general the results of the study show,

    1) Reach scale habitat variables were correlated with stream size and elevation and were the best descriptors of lamprey distribution.

    2) Unit type and dominant substrate were weakly associated with spawning lamprey; and

    3) Other ecological factors (i.e. presence of ammocetes, network distance from rearing or aestivation sites) may have had a stronger influence than habitat structure.

See 2005 final report for complete results and references cited above.

Freshwater Residence of Adult Pacific Lamprey

In 2006 we initiated a study to continue the examination of the adult freshwater phase of the Pacific lamprey life history by describing the duration, locations and habitat use of aestivating lamprey. Adult Pacific lamprey re-enter freshwater late April through June, aestivate 6-10 months, and spawn the following spring.  It is unknown where in the watershed lamprey aestivate, what habitats they occupy during aestivation, and whether they make another significant migration to the gravel beds before spawning. Our study aims to better describe this life history trait and to further describe habitat features associated with aestivation. Description of this habitat can be used to better focus conservation efforts for this species. Our approach is to implant radio tags at Smith River Falls (Umpqua Basin) in 40 adult lampreys returning from the ocean in the spring and track individuals throughout the following year using radio telemetry. We will describe movement throughout the year, the physical characteristics of Pacific lamprey over-winter habitats and document the location relative to spawning grounds.


Annual Reports and Publications:

Gunckel, S.L, K.K. Jones, and S.E. Jacobs. 2009. Spawning distribution and habitat use of adult Pacific and western brook lampreys in Smith River, Oregon. Pages 173-190 in L. R Brown, S.D. Chase, M.G. Mesa, R.J. Beamish and P.B. Moyle, editors. Biology, management and conservation of lampreys in North America. American Fisheries Society, Symposium 72, Bethesda, Maryland.

Gunckel, S.L., K.K. Jones, and S.E. Jacobs. 2006. Spawning distribution and habitat use of adult Pacific and western brook lamprey in Smith River, Oregon.  Oregon Department of Fish and Wildlife, Information Report 2006-1. Corvallis.

Relevant Information:

Oregon's Lampreys: Natural History, Status, and Analysis of Management Issues

ODFW Oregon Native Fish Status Report (2005)


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