Upper Columbia Spring Chinook Salmon, Steelhead, and Bull Trout Recovery

3.3Management Actions

In sum, there are at least 132 management programs and projects being implemented in the Upper Columbia Basin. If the programs are implemented correctly and monitored for compliance, most of the programs (103 programs) promote the survival of spring Chinook, steelhead, and bull trout; 16 should have no effect or may promote survival.⁵⁰ Thirteen programs may threaten the viability of Chinook, steelhead, and bull trout in the Upper Columbia Basin. All hatchery programs have the potential to threaten viability by reducing the diversity of locally derived stocks. For example, the Entiat and Leavenworth National Fish Hatchery programs use out-of-basin stocks, which if stray into natural spawning areas, may affect the diversity and perhaps spawning success of naturally produced spring Chinook and steelhead (see Section 3.5). On the other hand, hatchery programs may also support recovery by increasing abundance of listed species. The U.S. Bureau of Reclamation (BOR) and the Army Corps of Engineers (ACOE) have programs that may threaten the viability of Chinook, steelhead, and bull trout populations. The Chief Joseph Dam Project (ACOE) and the Okanogan Project (BOR) probably affected or may affect spatial structure and productivity by reducing connectivity and decreasing stream flows needed for rearing and spawning. Programs that are designed to protect property and lives from flood damage can decrease viability of populations by decreasing habitat diversity and complexity. This plan does not advocate programs that could result in loss of property or lives. The point here is that some of these programs are not necessarily consistent with measures for establishing viable fish populations.

A management practice that deserves to be highlighted is the introduction of exotic fish species into the Upper Columbia Basin. Of the approximately 41 fish species in the Upper Columbia Basin, 16 are exotics (see Section 2.2). One species, brook trout, threatens the viability of bull trout in the Upper Columbia Basin. Brook trout are well established in several streams in the Wenatchee, Entiat, Lake Chelan, Methow, and Okanogan subbasins. Hybridization between brook trout and bull trout has been observed in the Chiwawa Basin and in Icicle Creek (T. Hillman, BioAnalysts, personal observation). Hybridization “pollutes” the bull trout gene pool and can result in offspring that are often sterile. Brook trout can also displace bull trout from rearing areas. In some streams (e.g., Big Meadow, Beaver, and Eightmile creeks), brook trout are so well established that they may have greatly reduced the numbers of bull trout in them (USFWS 2002). Current fishing regulations limit the harvest of exotic species. This protects exotic species and could be considered a threat as it reduces potential harvest of fish that compete or prey on ESA-listed species.

3.4Harvest

Even the large aboriginal fishery in the upper reaches of the Columbia River did not significantly reduce the abundance of anadromous fish. The fishery at Kettle Falls, which is presently submerged under the waters of Lake Roosevelt, was second only to Celilo Falls in its overall ceremonial significance and productivity. In the 1800s, before establishment of commercial fisheries in the lower Columbia River, the combined aboriginal harvest of salmon and steelhead in the Upper Columbia River was estimated in excess of two million pounds annually (Koch and Cochran 1977).

Commercial fishing had a significant effect on the abundance of salmon and steelhead in the Columbia River. An intense industrial fishery in the lower Columbia River, employing traps, beach seines, gillnets, and fish wheels, developed in the latter half of the 1800s. In the early 1900s, troll fisheries developed to catch salmon even before they reached the Columbia River. The late-spring and early summer Chinook salmon returns, which constituted the heart of the Columbia River runs, were decimated by the early 1900s (Thompson 1951). As these run components rapidly declined, fishing shifted earlier, later, and to other species. These changes, for a time, numerically masked the precipitous decline in the sought-after late-spring and early summer fish.

By the early 1930s, mean escapement of spring Chinook into the Upper Columbia Basin upstream from Rock Island Dam had declined to fewer than 3,000 fish.⁵¹ That escapement would represent perhaps 12,000 fish arriving in the lower Columbia River, inasmuch as fishing rates exceeded 75% in that period. Mean returns of steelhead to the Upper Columbia Basin were lower than 4,000 fish in the first part of the 1930s. Harvest rates of 70%, and probably higher, were common before the 1940s. If one assumes a 70% harvest rate, returns of Upper Columbia steelhead to the estuary may have amounted to about 13,000 fish.

By the 1930s and 1940s, restrictions on fishing time and gear had increased. For example, purse seines were outlawed in 1917, whip seines in 1923, fish wheels in 1927 (in Oregon), seines and traps east of Cascade Locks in Oregon in 1927, drag seines, traps, and set nets in 1935 (Washington), and seasons were gradually shortened. Catch rates almost certainly were much higher than those appropriate for maximum sustained yield for several decades before then. Presently, fishing rates have been reduced well below historical levels and approach about 12% for spring Chinook and 13% for steelhead.⁵²

Intensive harvest not only affected abundance and productivity of fish stocks, but probably also the diversity of populations. Intense size-selective fishing is known to alter genetics of salmon with the result that adult size declines. Historically, intense gillnetting (a method that selectively captures larger fish) in the Columbia River may have increased the proportion of smaller fish in escapements, with potential increases in jack fractions and reduced fecundity of females. Three-ocean spring Chinook adults may have been selected against at earlier high fishing rates. Harvest may have truncated run-timing characteristics or separated runs into early and late components. Harvest also reduced escapements of adults into tributaries, resulting in a reduction of marine-derived nutrients into tributaries.

Fishing was likely an important factor leading to the decline of bull trout in the Upper Columbia Basin. Certain areas within the basin were targeted bull trout fisheries, and large numbers of bull trout were harvested (WDFW 1992). For example, bull trout were harvested commercially in Lake Chelan (Brown 1984). Currently, with the exception of a bull trout fishery on the Lost River, bull trout harvest is prohibited. Although bull trout harvest is prohibited, they are still vulnerable to take due to misidentification, hooking mortality, and poaching. Schmetterling and Long (1999) found that only 44% of anglers correctly identified bull trout, and anglers frequently confused related species (i.e., bull trout and brook trout). Incidental hooking mortality is known to vary from about 5% to 24% for salmonids caught on artificial lures, and between 16% and 58% for salmonids caught with bait (Taylor and White 1992; Schill 1996; Schill and Scarpella 1997). Bull trout are incidentally caught during the sockeye salmon fishery in Lake Wenatchee and also during open seasons for mountain whitefish (USFWS 2002). The effects of hooking mortality, incidental harvest, and poaching could be significant (Taylor and White 1992; Long 1997; Schmetterling and Long 1999).