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The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

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Common name: Olympic Mudminnow

Taxonomy: available through www.itis.gov

Identification: Wydoski and Whitney (1979); Page and Burr (1991).

Size: to 9 cm TL (Wydoski and Whitney 2003)

Native Range: Coastal lowlands of Olympic Peninsula, Washington, from Ozette Lake and Queets River drainage to upper Chehalis River drainage (Mongillo and Hallock 1999). Occasionally found in lower Deschutes River (Puget Sound drainage), apparently as a result of floodwater exchange with Chehalis River (Wydoski and Whitney 1979; Page and Burr 1991).

Alaska	Hawaii	Puerto Rico & Virgin Islands	Guam Saipan

Native range data for this species provided in part by NatureServe

Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Ecology: Generally found in lowlands in slow moving streams, marshes, ponds, wetlands, and other habitats with low water flow, muddy bottoms, and abundant aquatic vegetation. Primarily consumes benthic and aquatic invertebrates (ostracods, isopods, oligochaetes, mysids, mollusks, and insect larvae) (Mongillo and Hallock 1999).

Means of Introduction: Unknown.

Status: Established in Washington.

Impact of Introduction: The impacts of this species are currently unknown, as no studies have been done to determine how it has affected ecosystems in the invaded range. The absence of data does not equate to lack of effects. It does, however, mean that research is required to evaluate effects before conclusions can be made.

Remarks: The Olympic Mudminnow, orignally considered introduced in the northern portion of the Olympic peninsula (e.g., Ozette Lake, Queets River; Wydoski and Whitney 1979), has been found in two areas between the suspected "introductions": the Hoh and Quillayute rivers (Mongillo and Hallock 1997; 1999), which are north of the Queets River and south of Lake Ozette. These new discoveries suggest that this species is actually native throughout the Olympic peninsula but was unknown prior to recent sampling. Lake Ozette and the Chehalis River drainage were ice free during the most recent glaciation, providing refugia for Olympic Mudminnows and other species (Mongillo and Hallock 1999).

References: (click for full references)

Mongillo, P.E., and M. Hallock. 1997. Distribution and habitat of native nongame stream fishes of the Olympic Peninsula. Washington Department of Fish and Wildlife Technical Report #FRD 97-05. 45 pp.

Mongillo, P.E., and M. Hallock. 1999. Washington state status report for the Olympic mudminnow. Washington Department of Fish and Wildlife. 36 pp.

Page, L.M., and B.M. Burr. 1991. A field guide to freshwater fishes of North America north of Mexico. The Peterson Field Guide Series, volume 42. Houghton Mifflin Company, Boston, MA.

Trotter, P.C., B. McMillan, and D. Kappes. 2000. Occurrence of the Olympic mudminnow on the east side of the Puget Trough. Northwestern Naturalist 81(2):59-63.

Wydoski, R.S., and R.R. Whitney. 1979. Inland fishes of Washington. University of Washington Press, Seattle, WA.

Wydoski, R.S., and R.R. Whitney. 2003. Inland fishes of Washington. Second edition. University of Washington Press, Seattle, WA.

Other Resources:

Author: Matt Neilson, and Pam Fuller

Peer Review Date: 3/5/2012

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.