The historical presence of fish communities in this area is unknown, but Willamette River fish communities would have likely utilized the bottomland side channels and wetlands areas with connectivity to the river. Miller Creek likely provided off-channel as well as spawning and rearing habitat as far upstream as possible within flow and slope constraints.
Several fish species utilize Miller Creek. Both the railroad/Marina Way culvert and private marina access road culvert allow for some fish passage but likely impede fish migration during at least parts of the year. Field surveys conducted by the Bureau of Planning staff and ODFW biologists in 1990 found sea-run cutthroat trout, Coho salmon, and short-head cottid in Miller Creek in the unrestricted reach upstream of Highway 30 (City of Portland Bureau of Planning, 1991b). Steelhead have also been observed in Miller Creek (City of Portland Bureau of Planning, 1991b). Macroinvertebrate species were abundant and include various stoneflies, mayflies, caddisflies, water striders, and crayfish (City of Portland Bureau of Planning, 1991b).
Fish communities in Miller Creek have likely been impacted by vegetation management, flow modification, channel alteration, and road crossing activities in the subwatershed.