Columbia River Drainage Research Articles

Major reorganization of the Snake River modulated by passage of the Yellowstone Hotspot

ABSTRACT The details and mechanisms for Neogene river reorganization in the U.S. Pacific Northwest and northern Rocky Mountains have been debated for over a century with key implications for how tectonic and volcanic systems modulate topographic development. To evaluate paleo-drainage networks, we produced an expansive data set and provenance analysis of detrital zircon U-Pb ages from Miocene to Pleistocene fluvial strata along proposed proto-Snake and Columbia River pathways. Statistical comparisons of Miocene-Pliocene detrital zircon spectra do not support previously hypothesized drainage routes of the Snake River. We use detrital zircon unmixing models to test prior Snake River routes against a newly hypothesized route, in which the Snake River circumnavigated the northern Rocky Mountains and entered the Columbia Basin from the northeast prior to incision of Hells Canyon. Our proposed ancestral Snake River route best matches detrital zircon age spectra throughout the region. Furthermore, this northerly Snake River route satisfies and provides context for shifts in the sedimentology and fish faunal assemblages of the western Snake River Plain and Columbia Basin through Miocene–Pliocene time. We posit that eastward migration of the Yellowstone Hotspot and its effect on thermally induced buoyancy and topographic uplift, coupled with volcanic densification of the eastern Snake River Plain lithosphere, are the primary mechanisms for drainage reorganization and that the eastern and western Snake River Plain were isolated from one another until the early Pliocene. Following this basin integration, the substantial increase in drainage area to the western Snake River Plain likely overtopped a bedrock threshold that previously contained Lake Idaho, which led to incision of Hells Canyon and establishment of the modern Snake and Columbia River drainage network.

Drones, hydraulics, and climate change: Inferring barriers to steelhead spawning migrations

AbstractGlobal climate models suggest dramatic changes in the timing and form of future precipitation in the Pacific Northwest, United States. By some estimates, in the Columbia River drainage, basin‐wide snow‐water equivalencies could decrease by more than 50% before the end of the century, with locally more extreme variation. In the South Fork Clearwater River, Idaho, where hydraulic barriers are currently thought to partially limit ESA‐listed steelhead migrations, changes in precipitation that could exacerbate the intensity and timing of hydraulic barriers presents an obvious conservation concern. Evidence indicates that the strongest steelhead swimmers are capable of sustaining burst speeds for up to 20 s, with maximum speed being a function of fish size (length). Understanding hydraulic dynamics that have implications for migrating fish requires integration of high‐resolution hydraulic models with sufficient resolution to characterize the hydraulic experience of the fish. Unmanned aerial vehicles (drones) have recently emerged as useful platforms for measuring river ecosystems with high precision. Results from habitat surveys and hydraulic modeling can identify locations where intense hydraulic energy may preclude fish passage during critical migration periods. The current as well as future range of discharges can be evaluated with a spatially explicit hydraulic model to quantify when, where, and how long barriers to migration exist. Further, this approach provides a powerful tool for manipulating the digital physical channel form and presents a heuristic opportunity to test hydraulic scenarios to improve migration success.This article is categorized under: Water and Life > Nature of Freshwater Ecosystems Water and Life > Stresses and Pressures on Ecosystems Water and Life > Methods

Population structure of sea-type and lake-type sockeye salmon and kokanee in the Fraser River and Columbia River drainages.

Population structure of three ecotypes of Oncorhynchus nerka (sea-type Sockeye Salmon, lake-type Sockeye Salmon, and Kokanee) in the Fraser River and Columbia River drainages was examined with microsatellite variation, with the main focus as to whether Kokanee population structure within the Fraser River drainage suggested either a monophyletic or polyphyletic origin of the ecotype within the drainage. Variation at 14 microsatellite loci was surveyed for sea-type and lake-type Sockeye Salmon and Kokanee sampled from 121 populations in the two river drainages. An index of genetic differentiation, FST, over all populations and loci was 0.087, with individual locus values ranging from 0.031 to 0.172. Standardized to an ecotype sample size of 275 individuals, the least genetically diverse ecotype was sea-type Sockeye Salmon with 203 alleles, whereas Kokanee displayed the greatest number of alleles (260 alleles), with lake-type Sockeye Salmon intermediate (241 alleles). Kokanee populations from the Columbia River drainage (Okanagan Lake, Kootenay Lake), the South Thompson River (a major Fraser River tributary) drainage populations, and the mid-Fraser River populations all clustered together in a neighbor-joining analysis, indicative of a monophyletic origin of the Kokanee ecotype in these regions, likely reflecting the origin of salmon radiating from a refuge after the last glaciation period. However, upstream of the mid-Fraser River populations, there were closer relationships between the lake-type Sockeye Salmon ecotype and the Kokanee ecotype, indicative of the Kokanee ecotype evolving independently from the lake-type Sockeye Salmon ecotype in parallel radiation. Kokanee population structure within the entire Fraser River drainage suggested a polyphyletic origin of the ecotype within the drainage. Studies employing geographically restricted population sampling may not outline accurately the phylogenetic history of salmonid ecotypes.

Two new species of Fluminicola (Caenogastropoda, Lithoglyphidae) from southwest Oregon, USA, and a range extension for F. multifarius

We describe two new species of pebblesnails (Lithoglyphidae: Fluminicola) from southwest Oregon based on morphologic and mitochondrial DNA (COI, cytB) evidence. Fluminicola umpquaensis sp. n., which had been traditionally identified as F. virens prior to the recent restriction of the latter to the lower Columbia River drainage, lives in lotic habitats in the Umpqua River basin. This species is readily distinguished from closely related F. gustafsoni and F. virens by shell and anatomical characters, and by its mtDNA sequences (divergence >3.6% for both genes). Fluminicola fresti sp. n. ranges among lotic habitats in the North Umpqua River basin, and in the upper Rogue River drainage north of Little Butte Creek. This species differs from other congeners by >9.1% for both genes and is distinguished from closely similar and geographically proximal F. multifarius by several anatomical characters. Additionally, new records are provided for F. multifarius from the upper Rogue River basin south of Little Butte Creek, which extend the geographic range of this species about 80 km northward from the Sacramento River headwater region. This continues a recent series of taxonomic papers on the poorly known and little studied pebblesnail fauna of the vast Pacific watershed from northern California to southern British Columbia.

Investigating the effects of Pleistocene events on genetic divergence within Richardsonius balteatus, a widely distributed western North American minnow.

BackgroundBiogeographers seek to understand the influences of global climate shifts and geologic changes to the landscape on the ecology and evolution of organisms. Across both longer and shorter timeframes, the western North American landscape has experienced dynamic transformations related to various geologic processes and climatic oscillations, including events as recently as the Last Glacial Maximum (LGM; ~20 Ka) that have impacted the evolution of the North American biota. Redside shiner is a cyprinid species that is widely distributed throughout western North America. The species’ native range includes several well-documented Pleistocene refugia. Here we use mitochondrial DNA sequence data to assess phylogeography, and to test two biogeographic hypotheses regarding post-glacial colonization by redside shiner: 1) Redside shiner entered the Bonneville Basin at the time of the Bonneville Flood (Late Pleistocene; 14.5 Ka), and 2) redside shiner colonized British Columbia post-glacially from a single refugium in the Upper Columbia River drainage.ResultsGenetic diversification in redside shiner began in the mid to late Pleistocene, but was not associated with LGM. Different clades of redside shiner were distributed in multiple glacial age refugia, and each clade retains a signature of population expansion, with clades having secondary contact in some areas.ConclusionsDivergence times between redside shiner populations in the Bonneville Basin and the Upper Snake/Columbia River drainage precedes the Bonneville Flood, thus it is unlikely that redside shiner invaded the Bonneville Basin during this flooding event. All but one British Columbia population of redside shiner are associated with the Upper Columbia River drainage with the lone exception being a population near the coast, suggesting that the province as a whole was colonized from multiple refugia, but the inland British Columbia redside shiner populations are affiliated with a refugium in the Upper Columbia River drainage.

Comparison of population genetic patterns in two widespread freshwater mussels with contrasting life histories in western North America

We investigate population genetic structuring in Margaritifera falcata, a freshwater mussel native to western North America, across the majority of its geographical range. We find shallow rangewide genetic structure, strong population-level structuring and very low population diversity in this species, using both mitochondrial sequence and nuclear microsatellite data. We contrast these patterns with previous findings in another freshwater mussel species group (Anodonta californiensis/A.nuttalliana) occupying the same continental region and many of the same watersheds. We conclude that differences are likely caused by contrasting life history attributes between genera, particularly host fish requirements and hermaphroditism. Further, we demonstrate the occurrence of a 'hotspot' for genetic diversity in both groups of mussels, occurring in the vicinity of the lower Columbia River drainage. We suggest that stream hierarchy may be responsible for this pattern and may produce similar patterns in other widespread freshwater species.

River of Promise: Lewis and Clark on the Columbia by David L. Nicandri Clay S. Jenkinson

 OHQ vol. 112, no. 1 The last few pages of the book provide intriguing insights to the enigmatic figure of Senator Henry Jackson. An avowed cold warrior and an advocate of a strong American military, the “Senator from Boeing” was also a liberal on domestic issues, authoring some of the nation’s most important environmental laws and arguably the most significant political figure in bringing sovereignty to Indian people. Pacific Northwest tribes, in particular, worked closely with Jackson — even during his termination days — because he had a remarkable capacity to listen. Jackson’s association with Gerard, Trahant concludes, led to“steady progress on tribal control”(p. 116). Even in his two presidential bids, unlike other candidates, Jackson never used his successes on behalf of Indians to advance his candidacy. Trahant has special praise for the senator’s willingness to bring Forrest Gerard to the Senate Interior Committee and for refusing to use Indians as props to promote himself. Despite minor flaws — redundancies and too many lengthy quotations — this is a very revealing book. William G. Robbins Oregon State University River of Promise: Lewis and Clark on the Columbia by David L. Nicandri foreword by Clay S. Jenkinson University of Oklahoma Press, Norman, 2010. Illustrations, notes, bibliography, index. 325 pages. $29.95 cloth. $18.95 paper. When considering the Lewis and Clark Expedition and all the attention it received just a few years ago, it is hard to imagine that anything can or should be said about the subject — at least for a while.It is a pleasant surprise,then,to find much that is new and important in David Nicandri’s River of Promise: Lewis and Clark on the Columbia. As Clay Jenkinson notes in the book’s foreword, Nicandri provides a unique, close reading of the journals that will “inspire and pave the way for other scholars” in the post-bicentennial era (p. xiii). Nicandri is both a historian of the nineteenth -century Pacific Northwest, with a particular talent for the finer details of local history, and a long-time director of the Washington State Historical Society. The latter position made him a key player in the Lewis and Clark Bicentennial and provided a deep understanding of the event’s broad significance as well as its banal boosterism. This unique experience indirectly informs much of the book, which is equally concerned with enlarging scholarly understandings of the expedition as it is with reinterpreting stories and events associated with locally celebrated sites along the Columbia River drainage. This twin effort, and the skills Nicandri honed in the study of local histories, has been strengthened by the application of literary analysis. The result is a level of intellectual creativity that allows River of Promise to range, in the course of a single page,from minute details about the missteps of a packhorse in the Bitteroot Mountains to the narrative tropes and grand imperial concerns of late eighteenth and early nineteenth-century exploration. River of Promise has several theses, but much of the book, as Nicandri notes in his preface, is devoted to correcting “a significant shortcoming in the literature of the expedition [that stems from] the relatively small amount of analysis given to the voyage down the Snake and Columbia Rivers compared to the Missourian phases” (p. 3). As Nicandri makes plain, the Corps of Discovery found the area west of the Continental Divide to be more challenging than conditions on the Missouri River. It is in the Columbia drainage that Jeffersonian expectations about geography,commerce,and national destiny were most thwarted and challenged ,and that ideas and actions of the Corps of Discovery are most telling in their efforts to  Reviews resurrect or craft new geopolitical, personal, and interethnic understandings from scratch. By the time Lewis and Clark reached the lower Columbia River in October 1805, they were moving through a world already mapped by the British and dealing with Native peoples already connected to global trade networks. Lewis and Clark also feared (rightly) that they had not found the headwaters of the Columbia River, let alone the best route from eastern North America to the Pacific. Instead, their efforts seemed to confirm that Alexander MacKenzie, whose writings they carried...

Comparative maturation schedules of two Columbia River sockeye salmon Oncorhynchus nerka populations

Age and size at maturation affect an individual's reproductive success and reflect both evolutionary adaptations and phenotypic responses to environmental conditions. We evaluated age and size at maturity of sockeye salmon Oncorhynchus nerka from 2 populations within the Columbia River drainage: the Okanagan River, British Columbia (Canada), population and the endangered population from Redfish Lake, Idaho, USA. We compared available data on wild fish to data on fish reared under controlled laboratory conditions. Data obtained from the wild revealed that Okanagan River fish smolted at younger ages and larger sizes and then matured at younger ages than Redfish Lake fish. In captivity, fish from both populations were grown at the same rate and all smolted at Age 1. Despite their similar lengths as smolts, a greater proportion of Redfish Lake (>90%) than Okanagan River sockeye salmon (68%) matured 1 yr after smolt transformation. Calculated proba- bilistic maturation reaction norm midpoints for the captive fish indicated that Redfish Lake sockeye salmon in this study may have lower maturation thresholds than Okanagan River fish. Expression of different life history traits in the 2 populations under controlled conditions is consistent with a genetic basis for these traits and countergradient variation in maturation thresholds. Understanding life history differences and local adaptation among populations is important for their conservation, including anticipating responses to captive breeding regimes and supplementation, changing environmental conditions, and selective harvest.

Mitochondrial Variation and Biogeographic History of Chinook Salmon

AbstractThe genetic variation of many species in the Northern Hemisphere has been influenced by climatic changes during the Pleistocene Epoch. Phylogeographic studies can help determine intraspecific relationships and postglacial recolonization routes for many of these species, potentially leading to a more complete understanding of how flora and fauna respond to dramatic climate change. We analyzed the variation in the mitochondrial DNA sequences of Chinook salmon Oncorhynchus tshawytscha from California to the Kamchatka Peninsula, Russia, to gain insight into the role of Pleistocene glaciation in the genetic structuring of this species. The geographic distribution of haplotypes revealed high levels of genetic diversity in the Columbia River drainage. Nested clade analysis suggests northward expansion from this area during the late Pleistocene, a hypothesis that is further supported by evidence of demographic growth and population expansion in the northern portion of the species' range. Estimates of the divergence time between two phylogenetic clades are correlated with interglacial periods of the Pleistocene. The data suggest the absence of Chinook salmon from the current northern part of its distribution until the late Pleistocene, when northward expansion from a southern refugium occurred (during an interglacial period), followed by the recent genetic divergence of these northern populations.

Impact of the Potholes Reservoir Caspian Tern Breeding Colony on Out‐Migrating Juvenile Salmonids in the Mid‐Columbia River

AbstractWe examined the foraging behavior and diet of Caspian terns Hydroprogne caspia breeding at Potholes Reservoir, Washington, in 2003, 2005, and 2006, and we developed a bioenergetics model to estimate impacts on juvenile salmonids Oncorhynchus spp. from Columbia River stocks. Potholes Reservoir Caspian terns mostly foraged on local fish (68–97% of tern bill loads) rather than traveling to the Columbia River. Our model suggested that only 8,913–94,139 juvenile salmonids were consumed, representing 0.02–0.38% of the salmonids available to Caspian terns. Local foraging is probably explained by higher net profitability of Potholes Reservoir fish prey. Columbia River steelhead O. mykiss were the only juvenile salmonids that were energetically comparable with local Potholes Reservoir fish, mostly due to their high energy density and relatively large size. Passive integrated transponder tag analyses showed that Potholes Reservoir Caspian terns preferred steelhead (predation rates = 0.42–1.06%) to all other salmonid stocks (coho salmon O. kisutch = 0.09–0.36%; subyearling Chinook salmon O. tshawytscha = 0.009–0.040%; yearling Chinook salmon = 0.05–0.17%). Given the proposed reduction in nesting habitat at East Sand Island (ESI; where the current Caspian tern population consumes 3.6–5.3 million juvenile salmonids annually), we estimated the impact on salmonid stocks that would occur if ESI Caspian terns relocated to Potholes Reservoir. Depending on diet scenario, 100% relocation could result in juvenile salmonid consumption between 2.2 and 6.6 million fish, with lower values being much more likely, making Potholes Reservoir the colony location of least likely impact among all sites within the Columbia River drainage. We suggest that selection of sites for ESI relocation should be based on scientific evidence combining a quantitative approach, such as bioenergetics modeling linked to prey population growth rate.

Large-scale coastal change in the Columbia River littoral cell: An overview

This overview introduces large-scale coastal change in the Columbia River littoral cell (CRLC). Covering 165 km of the southwest Washington and northwest Oregon coasts, the littoral cell is made up of wide low-sloping dissipative beaches, broad coastal dunes and barrier plains, three large estuaries, and is bounded by rocky headlands. The beaches and inner shelf are composed of fine-grained sand from the Columbia River and are exposed to a high-energy winter wave climate. Throughout the Holocene, the CRLC has undergone large fluctuations in shoreline change trends, responding to a variety of coastal change drivers, including changing rates of sea-level rise, infrequent, yet catastrophic, co-seismic subsidence events, a large regional sediment supply, inter-annual climatic fluctuations (El Niño cycles), seasonally varying wave climate, and numerous anthropogenic influences. Human influences on the CRLC include construction of over 200 dams in the Columbia River drainage basin, dredging of navigation channels removing sand to upland sites and offshore deep-water sites, and construction of large inlet jetties at the entrances to the Columbia River and Grays Harbor. The construction of these massive entrance jetties at the end of the 19th century has been the dominant driver of coastal change through most of the littoral cell over the last hundred years. Presently, some beaches in the littoral cell are eroding in response to nearshore sediment deficits resulting from a) ebb-jets of the confined entrances pushing the previously large, shallow ebb-tidal deltas offshore into deeper water, and b) waves dispersing the nearshore delta flanks initially onshore and then alongshore away from the jetties. This overview describes 1) the motivation for developing a system-wide understanding of sediment dynamics in the littoral cell at multiple time and space scales, 2) the formation and approach of the Southwest Washington Coastal Erosion Study, and 3) an introduction to the papers in this special issue.

Grating Size Needed to Protect Adult Pacific Lampreys in the Columbia River Basin

AbstractAdult Pacific lampreys Lampetra tridentata routinely pass through picketed leads and diffuser gratings at lower Columbia River hydropower dams and enter areas where they can be delayed, injured, or killed. We assessed the bar spacing needed to exclude adult lampreys that enter the fishways at Bonneville Dam (river kilometer (rkm) 235). The experimental fish used (n = 242) ranged from 53 to 79 cm in total length and from 282 to 800 g in weight. All were able to swim through a 2.5‐cm vertical gap, 47% passed through a 2.2‐cm gap, and none passed through a gap of 1.9 cm or less. In dewatering simulations, none of the additional 50 Pacific lampreys tested were able to pass through a 1.9‐cm diffuser grating, while 86% were able to pass through a traditional 2.5‐cm grating. Based on these results, we conclude that bar spacing of 1.9 cm or less is needed to exclude most adult Pacific lampreys in the Columbia River drainage. An initial field test of the 1.9‐cm grating at John Day Dam (rkm 347) confirmed these results.

Crossing the Continental Divide: the Columbia drainage species Juga hemphilli (Henderson, 1935) is a cryptic member of the eastern North American genus Elimia (Cerithioidea: Pleuroceridae)

Pleurocerid gastropods are ecologically prominent and diverse members of the North American freshwater malacofauna. However, their systematic study has been greatly complicated by pronounced conchological variability. Almost 1,000 taxa have been described north of Mexico, although this inflated estimate has been reduced by serial synonymization to 152 or 153 nominal species, comprising seven genera. Pleurocerid diversity is not evenly spread across continental watersheds. Only nine nominal species, placed in the genus Juga, are found in the drainages west of the Rocky Mountains. Juga was expressly erected to house the western taxa, but there are no diagnostic conchological characters to separate them from eastern con-familials and they had previously been regarded as western lineages of Elimia (formerly known as Goniobasis ). Consequently, identification keys have used biogeographic criteria to distinguish Juga (west of the Continental Divide) from Elimia (east of the Continental Divide) taxa. Until recently, the systematic validity of the genus Juga was rather tenuous, resting primarily on hints of oviductal groove structural distinctions. However, molecular phylogenetic data have now clearly demonstrated Juga’s separate evolutionary history. In a study of North American pleurocerid relationships, three species of Juga, including the type species Juga silicula (Gould, 1847), formed a robust clade sister to all of the genotyped eastern taxa. A subsequent study incorporating a global sampling of Cerithioidea emphasized the phylogenetic distinctiveness of Juga, finding it to be sister to the eastern Asian pleurocerid genera Hua and Semisulcospira. However, not all Juga species have been incorporated into molecular phylogenies and there are morphological and karyological lines of evidence to suggest that some nominal taxa occurring in the Columbia River drainage may actually be geographically disjunct members of the eastern genus Elimia. A century ago, a species of pleurocerid, Goniobasis columbiensis Whiteaves, 1905, was described from material collected in 1883 by J.B. Tyrrell at the headwaters of the Columbia River that represented ‘the first non-plicate Goniobasis, of the type of G. livescens, that has been found in the Pacific drainage system.’ Goodrich examined Whiteave’s type material and found that the ‘shell characters and opercula are identical with those of livescens of Lake Erie,’ but concluded that they were more likely to represent mislabeled eastern specimens rather than a geographically disjunct western population. More recently, a karyological study of North American pleurocerid taxa included a single Juga species, J. hemphilli (Henderson, 1935), sampled from Benton County, Oregon that exhibited an identical ideogram to E. livescens (Menke, 1830). Though constrained by the lack of karyological data for other Juga taxa, this surprising result suggested to us that J. hemphilli might well represent a cryptic western Elimia lineage. Henderson described Juga hemphilli, together with two subspecies, from lower Columbia River drainage locations, although Goodrich subsequently listed it, together with Whiteave’s G. columbiensis, as a species incerta. The goal of our study was to phylogenetically test, using gene trees, the hypothesis that Juga hemphilli is a cryptic western member of the genus Elimia. Specimens of J. hemphilli dallesensis (Henderson, 1935), sampled from the type locality, were kindly provided by F.G. Thompson (Fig. 1) and, together with the representatives of all extant eastern North American pleurocerid genera except for Lithasia (Table 1), they were sequenced for a portion of the nuclear large subunit ribosomal gene (28S). The choice of this gene fragment was driven by the need to avoid a potentially confounding issue – within-species mitochondrial (mt) polyphyly – that has complicated freshwater cerithioidean molecular phylogenetic studies using exclusively mt markers. –24 This is especially pertinent for North American pleurocerid taxa where pronounced within-population mt heterogeneity may occur and the only available case of mt/ nuclear genome comparison is surprisingly incongruent. Mobile basin Leptoxis picta (Lea, 1841) and L. taeniata (Tyron, 1873) were indistinguishable in terms of allozyme frequencies at nine loci but exhibited highly divergent mt genotypes, both in terms of sequence divergence [19% for mt large RNA subunit (16S)] and phylogenetic placement. In addition to the target nuclear rDNA marker, we also took advantage of the extensive GenBank submissions of pleurocerid mt 16S

Astoria Fan sediments, DSDP site 174, Cascadia Basin: Hf–Nd–Pb constraints on provenance and outburst flooding

The Astoria submarine fan, located off the coast of Washington and Oregon, has grown throughout the Pleistocene from continental input delivered by the Columbia River drainage system. Enormous floods from the sudden release of glacial lake water occurred periodically during the Pleistocene, carrying vast amounts of sediment to the Pacific Ocean. Deep Sea Drilling Project (DSDP) site 174, located on the southern distal edge of the Astoria Fan, is composed of 879 m of terrigenous sediment. The section is divided into two major units separated by a distinct seismic discontinuity: an upper, turbidite fan unit (Unit I), and an underlying finer-grained unit (Unit II). Both units have overlapping ranges of Nd and Hf isotope compositions, with the majority of samples having ε Nd values of − 7.1 to − 15.2 and ε Hf values − 6.2 to − 20.0; the most notable exception is the uppermost sample in the section, which is identical to modern Columbia River sediment. Nd depleted mantle model ages for the site range from 2.0 to 1.2 Ga and are consistent with derivation from cratonic Proterozoic source regions, rather than Cenozoic and Mesozoic terranes proximal to the Washington–Oregon coast. The Astoria Fan sediments have significantly less radiogenic Nd (and Hf) isotopic compositions than present day Columbia River sediment ( ε Nd = − 3 to − 4; [Goldstein, S.J., Jacobsen, S.B., 1987. Nd and Sr isotopic systematics of river water suspended material: implications for crustal evolution. Earth. Planet. Sci. Lett. 87, 249–265.]), and suggest that outburst flooding, tapping Proterozoic source regions, was the dominant sediment transport mechanism in the genesis and construction of the Astoria Fan. Pb isotopes form a highly linear 207Pb/ 204Pb– 206Pb/ 204Pb array, and indicate the sediments are a binary mixture of two disparate sources with isotopic compositions similar to Proterozoic Belt Supergroup metasediments and Columbia River Basalts. The combined major, trace and isotopic data argue that outburst flooding was responsible for depositing the majority (top 630 m) of the sediment in the Astoria Fan.

Late Pleistocene outburst flooding from pluvial Lake Alvord into the Owyhee River, Oregon

At least one large, late Pleistocene flood traveled into the Owyhee River as a result of a rise and subsequent outburst from pluvial Lake Alvord in southeastern Oregon. Lake Alvord breached Big Sand Gap in its eastern rim after reaching an elevation of 1292 m, releasing 11.3 km 3 of water into the adjacent Coyote Basin as it eroded the Big Sand Gap outlet channel to an elevation of about 1280 m. The outflow filled and then spilled out of Coyote Basin through two outlets at 1278 m and into Crooked Creek drainage, ultimately flowing into the Owyhee and Snake Rivers. Along Crooked Creek, the resulting flood eroded canyons, stripped bedrock surfaces, and deposited numerous boulder bars containing imbricated clasts up to 4.1 m in diameter, some of which are located over 30 m above the present-day channel. Critical depth calculations at Big Sand Gap show that maximum outflow from a 1292- to 1280-m drop in Lake Alvord was ∼ 10,000 m 3 s − 1 . Flooding became confined to a single channel approximately 40 km downstream of Big Sand Gap, where step-backwater calculations show that a much larger peak discharge of 40,000 m 3 s − 1 is required to match the highest geologic evidence of the flood in this channel. This inconsistency can be explained by (1) a single 10,000 m 3 s − 1 flood that caused at least 13 m of vertical incision in the channel (hence enlarging the channel cross-section); (2) multiple floods of 10,000 m 3 s − 1 or less, each producing some incision of the channel; or (3) an earlier flood of 40,000 m 3 s − 1 creating the highest flood deposits and crossed drainage divides observed along Crooked Creek drainage, followed by a later 10,000 m 3 s − 1 flood associated with the most recent shorelines in Alvord and Coyote Basins. Well-developed shorelines of Lake Alvord at 1280 m and in Coyote Basin at 1278 m suggest that after the initial flood, postflood overflow persisted for an extended period, connecting Alvord and Coyote Basins with the Owyhee River of the Columbia River drainage. Surficial weathering characteristics and planktonic freshwater diatoms in Lake Alvord sediment stratigraphically below Mt. St. Helens set Sg tephra, suggest deep open-basin conditions at ∼ 13–14 ka ( 14C yr) and that the flood and prominent shorelines date to about this time. But geomorphic and sedimentological evidence also show that Alvord and Coyote Basins held older, higher-elevation lakes that may have released earlier floods down Crooked Creek.

STATUS AND DISTRIBUTION OF THE SAND ROLLER (PERCOPSIS TRANSMONTANA) IN THE WILLAMETTE BASIN, OREGON

The sand roller, Percopsis transmontana, is endemic and considered rare in the lower Columbia River drainage, including the Willamette River and its tributaries. Historical records in the Willamette Basin are scarce. In 2005, we surveyed historical and some recently documented locations to determine the current distribution of sand rollers in the Willamette River basin. Sand rollers were found at 41% of the locations sampled, including most Willamette River subbasins. Sand rollers preferred slow-water habitats in low gradient streams and were most frequently associated with roots, other large wood, and undercut banks over sand or gravel substrates. Sand rollers were more common at locations containing only native fishes; larger numbers were collected at locations where nonnative fish were absent. Infrequent reporting of this species is probably related to its secretive daytime behavior and to inefficient gear, rather than to actual rarity.

Genetic Structure of Chum Salmon (Oncorhynchus keta) Populations in the Lower Columbia River: Are Chum Salmon in Cascade Tributaries Remnant Populations?

The lower Columbia River drainage once supported a run of over a million chum salmon. By the late 1950s, the run had decreased to often a few hundred fish. With the exception of Grays River near the coast and an aggregation of chum salmon spawning in creeks and the main stem near Bonneville Dam in the Columbia Gorge, most populations were thought to be extinct. However, chum salmon consistently return in low numbers to tributaries originating in the Cascade Range: the Cowlitz, Lewis, and Washougal rivers. To assess whether Cascade spawners were strays or remnants of former populations, chum salmon from the Coastal, Cascade and Gorge ecoregional zones were characterized at 17 microsatellite loci. Significant heterogeneity in genotype distributions was detected between zones and collections formed regional groups in a neighbor-joining tree. Cascade collections had higher allelic richness and private alleles, and the Cowlitz River supported genetically divergent fall and summer runs, the only summer chum salmon run extant in the Columbia River drainage. We propose that chum salmon in the Cascade zone are remnants of original populations. We attribute the divergence between zonal groups to diverse ecological conditions in each zone, which promoted regional genetic adaptation, and to genetic drift experienced in small populations.

Biological and physical processes in and around Astoria submarine Canyon, Oregon, USA

Astoria Canyon represents the westernmost portion of the Columbia River drainage system, with the head of the canyon beginning just 16 km west of the mouth of the Columbia River along the northern Oregon and southern Washington coasts. During the summer of 2001, physical, chemical, and biological measurements in the canyon were taken to better understand the hydrodynamic setting of, and the feeding relationships among, the pelagic and benthic communities. Results show that currents were strongly tidal, and transport, where measured, was primarily up and into the canyon below shelf depth as previous studies in the canyon have shown. Temperature time series suggests that the largest diurnal oscillations occurred at, or were trapped near, the bottom of the canyon. Within the upper canyon, subtidal temperature was correlated with upper-level shelf-edge currents, linking subtidal upwelling events in the canyon with near-surface subtidal along-shore flow. Invertebrates, such as shrimp, euphausiids, and squid, as well as mesopelagic fishes, dominated the Isaacs–Kidd midwater trawl catches along the canyon walls. Large trawl catches were comprised mainly of hake and rockfishes (shallow trawls) and macrourids, scorpaenids, stomiids, and zoarcids (bottom trawls). Gut-content analysis of rockfishes and lanternfishes revealed substantial use of midwater prey such as euphausiids and mesopelagic fishes. The δ 13C values of fishes and invertebrates reflected local primary production, as indicated by particulate organic matter (POM) δ 13C values from samples collected at various depths along the axis of the canyon, as well as across the canyon at several sites. The δ 15N values of fishes and invertebrates indicated lanternfishes, along with euphausiids, amphipods, shrimp and squid, may be important dietary components of higher-trophic-level fishes in both the benthic and benthopelagic food webs. The δ 13C and δ 15N values of Sebastes species showed significant enrichment in the adults of species that are largely piscivorous relative to the values of adults of more omnivorous species.

"Adventure" of the Colonel Allan

H. Lloyd Keith "Adventure" of the Colonel Allan oats of mail? Women's hosiery? Military shoes? At a fur trading post? One can imagine the astonishment of the new manager at Fort George in 1822 as he discovered these items and more among the trade goods leftbehind by the previous proprietors. Chief Factor J.D. Cameron of the Hudson's Bay Company arrived at the former Astoria near themouth of the Columbia River on November 8,1821, to assume command of the old trading post. When his canoe pulled alongside the rain-washed wharf, he noticed a crane for landing and loading goods. Amenities such as thiswere uncommon at his previous postings. Looking landward through misting clouds, a few hundred yards away he saw for the first time an imposing palisade some twelve or fifteen feet high enclosing nearly an acre of ground. Two bastions protected the fort'swalls with four- and six-pound cannon, and loopholes were provided along an interior gallery formuskets and swivel guns. Inside he would find two eighteen-pound cannons. All this arma ment protected a bevy of buildings, large and small, and an inventory of trade goods second in value only to those at FortWilliam, the old North West Company headquarters on thewestern shore of Lake Superior.1 Following themerger of theNorth West and Hudson's Bay companies in 1821,Cameron assumed charge of the newly acquired Columbia Depart ment. This vast trading area spilled over the Columbia River drainage to theThompson River in the north, southward as far as the Spanish territo ries, and extended from the Rocky Mountains to the Pacific Ocean. After completion of a thorough inventory of goods on hand at Fort George (the erstwhile Astoria and department headquarters), Cameron wrote awither ing letter acquainting theHudson's Bay Company officers of the status of their new acquisition: "The stock of goods [are] very great, and among the Number of articles tho' very expensive, yet are very useless articles in this 546 OHQ vol. 105, no. 4 ? 2004 Oregon Historical Society QHS neg., QrHi 35111 At the time of theColonel Allan s visit in 1816, Fort George was an enclosure of nearly an acre with fifteen-foot pickets. By 1845, when Henry James Warre traveled to the site and made the drawing on which this lithograph was based, theformer headquarters of theColumbia Department had been reduced to thesefew bucolic structures. Country."2 He had never before seen such items among the goods of a fur trading post, and he was appalled. There were four coats of steel-wire mail; ostrich and hackle feathers; hand grenades; men's, women's, and children's fine hosiery; men's military shoes; fine corduroy jackets and trousers; and fine gingham and silkumbrellas.3 There were also two eighteen-pound can nons, cannon carriages, and 240 rounds of ammunition. George Simpson, Cameron's superior and the Hudson's Bay Company's field governor in western North America, complained that "everything appears tome on theColumbia on too extended a scale except theTrade?4 To understand how and why such items appeared in the inventory at Fort George, one must look to the adventure of theNorth West Company's brig Colonel Allan. The story surrounding that venture also offers insights into theCompany's effort to diversify its trading strategy by plying goods in South America, California, and the Sandwich Islands (now Hawai'i) as well as offering itsColumbia furs for sale in Europe rather than China. Keith, "Adventure" of the Colonel Allan 547 Following the merger of the North West Company and the Hudson's Bay Company in 1821, the Columbia Department eventually experienced one of the greatest financial turnabouts in fur-trade business history. It had been a constant financial drain for theMontreal-based North West Company between 1813 and 1821,but by the end of the decade the Columbia Department had been transformed into a vital economic enterprise.5Much of this financial turn around has been attributed to the reforms introduced by HBC Governor George Simpson as a consequence of his 1824-1825 visit to the Columbia as well as to the Company's earlier decision tomarket Columbia pelts in Europe instead of China.6 Simpson...

A Comparison of Migration Rates of Radio‐ and PIT‐Tagged Adult Snake River Chinook Salmon through the Columbia River Hydropower System

Documentation of adult salmonid migration behavior in the Columbia River drainage is critically needed to assess the effects of dams on travel time and passage. In 2000, we compared the upstream travel times of passive integrated transponder (PIT)-tagged and radio-tagged adult chinook salmon Oncorhynchus tshawytscha from Bonneville Dam on the lower Columbia River to Lower Granite Dam on the Snake River. We found no evidence that radio tagging negatively affected chinook salmon behavior. In fact, their median travel time (14.1 d, range = 7.8-44.4 d, N = 113) was actually faster (statistically significant at P = 0.005) than that for PIT-tagged fish (median = 15.9 d, range = 8.9-67.4 d, N = 164) after accounting for temporal effects (i.e., Bonneville Dam passage date). However, we concluded this difference was not biologically significant and was probably related to differences in study design or data complications. This study indicated that radio transmitters weighing less than 2% of chinook salmon body weight and the handling associated with implanting those tags did not negatively affect temporal rates of fish movement from dam to dam.