Mainstem Columbia River Research Articles

Phenotypic variability of rusty crayfish (Faxonius rusticus) at the leading edge of its riverine invasion

Abstract Species around the globe are undergoing phenotypic shifts at ecologically relevant timescales as they invade new ecosystems and respond to changing environments. Disentangling the contribution of environmental gradients from the process of range expansion in shaping these changes, and identifying the specific traits undergoing selection, are both critical to anticipate the secondary spread and impact of invasive species. Here, we investigate phenotypic changes in rusty crayfish (Faxonius rusticus), a nuisance invasive species, through an extensive survey of their invasion gradient in multiple tributaries of the John Day River (JDR, Oregon, U.S.A.), a major tributary of the Columbia River. Rusty crayfish in the JDR have developed better physiological condition (intrinsic growth and/or reproductive potential measured as RNA/DNA ratio) but less competitive morphology (lighter body and smaller claws) as they spread upstream and downstream from their location of initial introduction. In addition, rusty crayfish in invasion front populations are at a lower trophic level than conspecifics closer to core areas. By accounting for variations in temperature, primary productivity, and prey (macroinvertebrates) biomass throughout the invasion extent of rusty crayfish, our findings suggest that low conspecific densities at the invasion edge and spatial sorting primarily drive these phenotypic changes. The trends observed here are thus likely to intensify over time as rusty crayfish continues to rapidly spread throughout the JDR and reach the mainstem Columbia River. Our study shows that phenotypic shifts can manifest rapidly over environmental gradients experienced during the range expansion of aquatic invasive species. Patterns in both morphological and functional traits documented in the JDR demonstrate the importance of both environmental factors and dispersal processes in shaping these responses in riverine networks.

Hydropower and high productivity in the Hanford Reach: A synthesis of how flow management may benefit fall Chinook Salmon in the Columbia River, USA

The fall Chinook Salmon (Oncorhynchus tshawytscha) population that spawns in the Hanford Reach of the Columbia River, USA is paradoxical because it is located above 4 and below 10 main stem Columbia River dams and yet is one of the largest and most productive C. salmon populations in the Pacific Northwest. A synthesis of information collected in the Hanford Reach reveals that the hydrosystem above the Hanford Reach and the management of river flows may have contributed to the recent size and productivity of this salmon population. Mechanisms for high survival and capacity at each freshwater life stage have been identified. Plausible mechanisms for contributing to high spawning capacity include: (a) more spawning habitat available during the spawning period. Plausible mechanisms for high egg‐to‐presmolt survival include: (a) reduced desiccation of redds, (b) reduced scour of redds, (c) reduced sedimentation in redds, (d) improved flow exchange within redds, and (e) increased food availability. Smolt survival may also be enhanced through the large size they attain in the Hanford Reach. This synthesis of information provides an uncommon assessment of some the positive effects of flow management from hydropower dams on a valued native fish that has occurred over the last three decades. WIREs Water 2018, 5:e1275. doi: 10.1002/wat2.1275This article is categorized under: Water and Life > Stresses and Pressures on Ecosystems Water and Life > Conservation, Management, and Awareness

Emergency Fish Passage at a Fractured Mainstem Columbia River Dam

On February 24, 2014, a hydro mechanic from Grant County Public Utility District (PUD) discovered an anomaly in the handrail and track on the deck of Wanapum Dam, a structure that spans the 2.6-km-...

River Lamprey (Lampetra ayresii) Outmigrant Upstream of the John Day Dam in the Mid-Columbia River

The anadromous River Lamprey (Lampetra ayresii) is known to occur in North America from Alaska to central California, generally in association with larger estuarine systems (such as the Fraser River in British Columbia, the Sacramento River in California, and the Columbia River in Washington-Oregon; Vladykov and Follett 1958; Weitkamp and others 2015). Its occurrence in the Columbia River basin, however, has not been well documented. Although small numbers of juvenile (feeding phase) River Lamprey have been captured incidentally in the Columbia River Estuary (Bond and others 1983; Weitkamp and others 2012, 2015), there are few records of this species in freshwater (Kostow 2002). The farthest upriver report in the Columbia River basin is a March 1940 record at Bonneville (presumably at Bonneville Dam), 235 river kilometers (rkm) from the Pacific Ocean (Vladykov and Follett 1958). However, adult River Lamprey (117to 324-mm total length; Vladykov and Follett 1958; Bond and others 1983; Wydoski and Whitney 2003; Weitkamp and others 2015) are less noticeable than the larger Pacific Lamprey (Entosphenus tridentatus) (700to 800-mm total length; Clemens and others 2010) and might spawn in deep water in large river systems similar to other lamprey species (Dawson and others 2015). Thus, even when abundant, they are rarely observed in freshwater (Beamish 1980; Beamish and Youson 1987). Furthermore, during its prolonged freshwater larval stage, it is difficult or impossible to distinguish River Lamprey, either morphologically or genetically, from the closely related and widely distributed Western Brook Lamprey (Lampetra richardsoni) (Docker 2009). The nonmigratory, non-trophic adult Western Brook Lamprey (90to 180-mm total length) can be distinguished from adult River Lamprey by morphological and dentition characters (Wydoski and Whitney 2003; Docker 2009). There is a growing conservation concern for lampreys worldwide. Like other species, the River Lamprey is susceptible to various freshwater threats such as dredging and barriers to migration (Maitland and others 2015). The Columbia River Basin is currently fragmented by many mainstem hydropower, navigation, and flood-control dams, as well as numerous additional dams and irrigation diversions in tributary systems. Many of these dams do not provide fish passage and those that do are likely problematic for migratory adult lampreys (Moser and others 2015). Documentation of River Lamprey in the Columbia River basin would help inform management of this highly regulated system, as well as elucidate distribution patterns to aid conservation. A current effort is underway to increase the monitoring of outmigrating juvenile lampreys through the operation of salmonid smolt monitoring systems at mainstem Columbia River dams (Fish Passage Center 2014). Subsamples of juvenile (metamorphosed to outmigrating phase) and larval (unmetamorphosed) lampreys are collected, anesthetized, identified (to species for juvenile lampreys and to genus for larval lampreys), measured, and assessed for body condition. A putative juvenile (recently metamorphosed) River Lamprey was collected at the John Day Dam smolt bypass facility on 28 May 2013 from a sample time frame of 13:00 to 07:00. The fish was 144-mm total length and weighed 3.1 g. Its dentition pattern clearly distinguished it from the relatively more common Pacific Lamprey (Fig. 1). Pacific Lamprey have 3 large cusps on the supra-oral lamina, 4 pairs of lateral teeth, and 1 row of posterior teeth; whereas the River Lamprey has 2 cusps on the supra-oral lamina, 3 pairs of lateral teeth, and no posterior teeth (Wydoski and Whitney 2003). Its caudal pigmentation was likewise consistent with Lampetra spp. (Fig. 2, Fig. 3); lampreys in the Entosphenus genus possess a lighter caudal ridge, whereas the caudal ridge of Lampetra spp. is uniformly dark (Goodman and others GENERAL NOTES

Signals of climate, conspecific density, and watershed features in patterns of homing and dispersal by Pacific salmon.

It is widely assumed that rates of dispersal in animal populations are plastic in response to intrinsic and extrinsic cues, yet the factors influencing this plasticity are rarely known. This knowledge gap is surprising given the important role of dispersal in facilitating range shifts that may allow populations to persist in a rapidly changing global climate. We used two decades of tagging and recapture data from 19 hatchery populations of Oncorhynchus tshawytscha (Chinook salmon) in the Columbia River, USA, to quantify the effects of regional and local climate conditions, density dependence, watershed features such as area and position on the landscape, and direct anthropogenic influence on dispersal rates by adult salmon during the breeding season. We found that the probability of dispersal, termed "straying" in salmon, is plastic in'response to multiple factors and that populations showed varied responses that were largely idiosyncratic. A regional climate index (Pacific Decadal Oscillation), water temperatures in the mainstem Columbia River that was commonly experience by populations during migration, water temperatures in local subbasins unique to each population during the breeding season, migration distance, and density dependence had the strongest effects on dispersal. Patterns of dispersal plasticity in response to commonly experienced conditions were consistent with gene by environment interactions, though we are tentative about this interpretation given the domesticated history of these populations. Overall, our results warn against attempts to predict future range shifts of migratory species without considering population-specific dispersal plasticity, and also caution against the use of few populations to infer species-level patterns. Ultimately, our results provide evidence that analyses that examine the response of dispersal to single factors may be misleading.

Rearing in natural and recovering tidal wetlands enhances growth and life-history diversity of Columbia Estuary tributary coho salmon Oncorhynchus kisutch population.

This study provides evidence of the importance of tributary tidal wetlands to local coho salmon Oncorhynchus kisutch populations and life-history diversity. Subyearling and, to a lesser extent, yearling O. kisutch life histories utilized various estuary habitats within the Grays River, a tidal freshwater tributary of the Columbia River estuary, including restoring emergent wetlands and natural forested wetlands. Migration timing data, size distributions, estuary residence and scale patterns suggest a predominance of subyearling migrant life histories, including several that involve extended periods of estuary rearing. Estuarine-rearing subyearling O. kisutch exhibited the greatest overall growth rates; the highest growth rates were seen in fish that utilized restoring emergent wetlands. These results contrast with studies conducted in the main-stem Columbia River estuary, which captured few O. kisutch, of which nearly all were hatchery-origin yearling smolts. Restoration and preservation of peripheral and tributary wetland habitats, such as those in the Grays River, could play an important role in the recovery of natural O. kisutch populations in the Columbia River and elsewhere.

Comparison of DIDSON sonar based estimates of Chinook salmon escapement with other methods in the Coweeman River, Washington.

The Coweeman River supports a small spawning population of Tule fall Chinook salmon (200–2000 adults), which are listed for protection under the US Endangered Species Act but harvested in mixed stock Pacific Ocean and mainstem Columbia River fisheries. The Coweeman Chinook stock has a low proportion of hatchery spawners and has been used as an index population for other less intensively monitored Tule populations. Over the last decade the Washington Department of Fish and Wildlife (WDFW) and partners have funded numerous studies to determine effective methods to accurately estimate Chinook salmon escapement for this population. From 2007 to 2009, a DIDSON sonar was operated below the major spawning area to estimate escapement. Concurrently, independent escapement estimates were made using more traditional methods such as mark‐recapture, red counts, and area‐under‐the curve surveys. Bayesian approaches to estimate salmon escapement for all methods will be presented, with an emphasis on the use of mixture models for sonar‐based estimates and a comparison of the sonar estimates with more traditional approaches.

First Documented Spawning of White Sturgeon in the Lower Willamette River, Oregon

White sturgeon (Acipenser transmontanus) in the lower Columbia River system were previously known to spawn in only one area; within the 12 km of mainstem Columbia River downstream of Bonneville Dam. Our work provides the first documentation of white sturgeon spawning in the Willamette River, Oregon, a major tributary of the lower Columbia River. We used artificial substrates to sample for white sturgeon eggs downstream of Willamette Falls from 18 May to 20 May 2009 and collected a total of 22 fertilized eggs. Embryonic developmental stages ranged from pigmentation change (Stage 2) to early epithelial (Stage 8), corresponding to fertilization times of approximately 5–17 hours prior to collection. We estimated that spawning occurred between 2100 hours on 19 May and 0900 hours on 20 May 2009, and that a minimum of three independent spawning events took place during that time. Results suggest that the area immediately downstream of Willamette Falls may be important white sturgeon spawning habitat, and that the lower Willamette River is likely an additional source of production for the white sturgeon population in the lower Columbia River system.

Impacts of the Columbia River Hydroelectric System on Main-Stem Habitats of Fall Chinook Salmon

Salmonid habitats in main-stem reaches of the Columbia and Snake rivers have changed dramatically during the past 60 years because of hydroelectric development and operation. Only about 13% and 58% of riverine habitats in the Columbia and Snake rivers, respectively, remain. Most riverine habitat is found in the upper Snake River; however, it is upstream of Hells Canyon Dam and not accessible to anadromous salmonids. We determined that approximately 661 and 805 km of the Columbia and Snake rivers, respectively, were once used by fall chinook salmon Oncorhynchus tshawytscha for spawning. Fall chinook salmon currently use only about 85 km of the main-stem Columbia River and 163 km of the main-stem Snake River for spawning. We used a geomorphic model to identify three river reaches downstream of present migration barriers with high potential for restoration of riverine processes: the Columbia River upstream of John Day Dam, the Columbia-Snake-Yakima River confluence, and the lower Snake River upstream of Little Goose Dam. Our analysis substantiated the assertion that historic spawning areas for fall chinook salmon occurred primarily within wide alluvial floodplains, which were once common in the main-stem Columbia and Snake rivers. These areas possessed more unconsolidated sediment and more bars and islands and had lower water surface slopes than did less extensively used areas. Because flows in the main stem are now highly regulated, the predevelopment alluvial river ecosystem is not expected to be restored simply by operational modification of one or more dams. Establishing more normative flow regimes—specifically, sustained peak flows for scouring—is essential to restoring the functional characteristics of existing, altered habitats. Restoring production of fall chinook salmon to any of these reaches also requires that population genetics and viability of potential seed populations (i.e., from tributaries, tailrace spawning areas, and hatcheries) be considered.

Status of Fall Chinook Salmon Populations in the Mid-Columbia River, 1948–1992

Abstract Historically, fall Chinook salmon Oncorhynchus tshawytscha spawned in the main-stem Columbia River over a distance of approximately 900 km. However, because of hydroelectric development and other human activities, most natural production of upriver stocks of fall Chinook salmon (upriver bright, URB) is now restricted to a 90-km-long section of river known as the Hanford Reach. The adjacent Hanford Nuclear Reservation was managed for production of nuclear materials from 1943 to 1971, which restricted many development activities, including additional hydroelectric projects. Aerial counts of fall Chinook salmon redds since 1948 at the Hanford Reach provide an index of relative abundance among spawning areas and years. Redd counts during peak spawning were less than 1,000 annually from 1948 to 1961, but they increased to as high as 8,800 in 1989 following construction of several main-stem dams on both the Columbia and Snake rivers. Escapement of adult fall Chinook salmon to the Hanford Reach averaged...

Age and Length of Steelhead Smolts from the Mid-Columbia River Basin, Washington

Steelhead Onchorhynchus mykiss exhibit a wide range of life histories within and among stocks. Varying degrees of anadromy, length of freshwater life before emigration to the sea, and age at first maturity have been observed. Steelhead in the mid-Columbia River basin are at least partially descended from fish that were relocated to the major tributaries of the mid-Columbia River when Grand Coulee Dam was built. These fish do not spawn in the main-stem Columbia River and are strictly tributary spawners. Rearing conditions in these tributaries can be harsh. Researchers have observed a wide range of lengths and ages of juvenile O. mykiss (steelhead and nonanadromous rainbow trout) in these tributaries. This led to a need to document the age at migration of fish that were clearly smolts, as demonstrated by their downstream migration. Over 970 otoliths were collected from naturally produced steelhead smolts in 1988 and 1989 to determine the age at migration. Ages ranged from 1 to 7 years at Rock Island Dam and from 1 to 5 years at Rocky Reach Dam. These ages agreed with those estimated from adult otoliths. Age structure did not differ significantly between the two sampling sites, but length did, suggesting that fish emigrating from the Wenatchee River were shorter for a given age than fish produced above Rocky Reach Dam. Females made up 63.0% of the smolts collected at Rock Island Dam and were generally older than males, suggesting that males have a higher probability of remaining in freshwater. We attempt to explain the patterns observed in age and length of naturally produced steelhead smolts. We suggest that a more or less continuous downstream movement of juveniles occurs that takes them to areas with more adequate food supplies. Smoltification of individual fish appears to result as a threshold length is approached. Harsher growing conditions result in slower growth and older smolts, which may have implications for supplementation and introduction of steelhead where resident rainbow trout are present.

Spawning and Rearing Habitat Use by White Sturgeons in the Columbia River Downstream from McNary Dam

Spawning and rearing habitats used by white sturgeons Acipenser transmontanus were described from water temperature, depth, and velocity measurements and substrate types present at sites where eggs, larvae, young-of-the-year, and juveniles (ages 1–7) were collected. Spawning and egg incubation occurred in the swiftest water available (mean water column velocity, 0.8–2.8 m/s), which was within 8 km downstream from each of the four main-stem Columbia River dams in our study area. Substrates where spawning occurred were mainly cobble, boulder, and bedrock. Yolk-sac larvae were transported by the river currents from spawning areas into deeper areas with lower water velocities and finer substrates. Young-of-the-year white sturgeons were found at depths of 9–57 m, at mean water column velocities of 0.6 m/s and less, and over substrates of hard clay, mud and silt, sand, gravel, and cobble. Juvenile fish were found at depths of 2–58 m, at mean water column velocities of 1.2 m/s and less, and over substrates of hard clay, mud and silt, sand, gravel, cobble, boulder, and bedrock.

Past and present water-quality conditions in the Hanford Reach, Columbia River

Twelve water quality variables from upstream and downstream locations in the Hanford Reach of the mainstem Columbia River, southcentral Washington, were compared statistically for the two time periods 1951 to 1953 and 1986 to 1988. During the 1951 to 1953 period, beta radioactivity and, most likely, water temperatures in the Hanford Reach were significantly higher downstream than upstream, while dissolved oxygen and sulfate were significantly lower. The increased beta radioactivity and temperature downstream were due to the discharge of cooling water from five single-purpose production reactors then operating on the Hanford Site. The last production reactor closed in January 1971. During the 1986 to 1988 period, beta radioactivity and water temperatures were similar upstream and downstream, but nitrate nitrogen had become significantly higher downstream. Comparison of 1951 to 1953 with 1986 to 1988 showed, as expected, that beta radioactivity was much lower today, at essentially background levels. Phosphate in the Hanford Reach had decreased significantly over the 35 year interval, while biochemical oxygen demand, dissolved oxygen, and nitrate nitrogen had increased. These changes, while detectable statistically, were relatively small. Today, the quality of water in the Hanford Reach remains well within Washington State standards for Class A waters. Occasional low pH values, which appear to orginate upriver, violate these standards.