The Rogue River is unique, with an ecosystem much more similar to California watersheds than any coastal watersheds in Oregon. Rogue salmon and steelhead are included in management units with California salmon and steelhead, rather than with Oregon coastal populations.
Spring Chinook
The Rogue River’s spring Chinook salmon, particularly the early-returning, early-spawning portion of the population, declined drastically following construction and operation of William Jess Dam and Lost Creek Reservoir. With post-dam spawning habitat limited to approximately 30 miles of the river between the Gold Ray area and Cole Rivers Fish Hatchery as well as Big Butte Creek, the population remains below the desired status level outlined in the 2007 Rogue River Spring Chinook Conservation Plan. The plan outlines management actions to restore numbers of naturally-produced spring Chinook, with a focus on safe reservoir operation by the U.S. Army Corps of Engineers to benefit spring Chinook.
While the population is below desired status levels (10-year average return of over 15,000), returns in recent years are well above levels that trigger conservation concerns. The estimate of abundance in 2014 was 5,593 naturally produced spring Chinook on the Rogue, but the 2015 estimate is expected to be 15,320 fish.
Steelhead
Summer steelhead is the iconic fish species of the Rogue going back to the days of author Zane Grey. Summer steelhead on the Rogue are different than any other summer steelhead in Oregon. The primary difference is their “half pounder” life history. After only a few months at sea, Rogue summer steelhead swim back to the river in late summer as 12 to 14 inch fish to rear and feed. Later, the fish head back to sea before returning on a spawning run. Because time spent in the ocean is reduced, Rogue summer steelhead do not grow as large as steelhead in rivers to the north (most are less than 24 inches in length), but the half pounder run provides a popular fishery in the lower river.
Rogue summer steelhead rear for up to three (or occasionally four) years in freshwater before migrating to sea, relying on good stewardship of Rogue streams to reach the age and size of a smolt to survive the ocean migration. During their time in freshwater, many juveniles migrate back and forth seasonally between small streams and the Rogue River. Barriers such as poorly-placed culverts can easily block migration by juvenile fish and greatly affect smolt production in the river. The fish have evolved to spawn successfully in small and intermittent streams, but these streams are often ignored and not considered to be fish streams by the general public.
The Oregon Department of Fish and Wildlife (ODFW) believes that summer steelhead are a priority for restoration on the Rogue. Returns meet population health goals on many years but not on an annual basis. Reliance on sensitive habitat is the primary reason for priority status. Restoration will not only ensure a healthy, sustainable population of summer steelhead in the Rogue but will benefit other fish species as well.
Coho salmon
Coho salmon are listed as threatened on the federal Endangered Species List as part of the Southern Oregon Northern California Coast (SONCC) ESU, and are the only federally-listed fish species on the Rogue. The ODFW organized an expert panel to identify the factors limiting coho production in the Rogue watershed. Unlike coho found in the rest of western Oregon, the expert panel considered summer temperatures and low streamflow to be among the primary limiting factors for Rogue coho. Restoration of summer streamflow and riparian vegetation to keep streams cool will help produce more coho on the Rogue.
ODFW supports restoration actions that address the limiting factors identified in the expert panel summary for coho in the Oregon portion of SONCC. Restoration projects that benefit both coho and summer steelhead – fish that rear in freshwater streams for at least one year – will provide the biggest ecological benefit for Rogue fish populations.