Freshwater Mussels Research and Restoration Project
Annual Report 2003 - 2004 November 2005 DOE/BP-00011402-2
This Document should be cited as follows:
Howard, Jeanette, "Freshwater Mussels Research and Restoration Project", 2003-2004 Annual Report, Project No. 200203700, 94 electronic pages, (BPA Report DOE/BP-00011402-2)
Bonneville Power Administration P.O. Box 3621 Portland, OR 97208
This report was funded by the Bonneville Power Administration (BPA), U.S. Department of Energy, as part of BPA's program to protect, mitigate, and enhance fish and wildlife affected by the development and operation of hydroelectric facilities on the Columbia River and its tributaries. The views in this report are the author's and do not necessarily represent the views of BPA.
FRESHWATER MUSSEL RESEARCH AND RESTORATION PROJECT
2004 ANNUAL REPORT
Prepared by:
Jeanette K. Howard, Jayne Brim Box and David Wolf Confederated Tribes of the Umatilla Indian Reservation Department of Natural Resources Fisheries Program Pendleton, Oregon 97801, USA
Prepared for: U.S. Department of Energy Bonneville Power Administration Environment, Fish and Wildlife Department P.O. Box 3621 Portland Oregon 97208-3621
Project Number: 2002-037-00 Contract Number: 00011402
November 2005
TABLE OF CONTENTS
Title page ...... 1 Table of contents...... 2 Executive summary...... 3
Chapter One: Multi-scale investigation into the distribution of freshwater mussels...... 5 Introduction...... 6 Study area...... 10 Multi-scale perspective on mussel distribution...... 11 Network distribution and species composition (Macroscale)...... 11 Introduction...... 11 Methods...... 12 Results...... 14 Reach-level channel types and mussel distribution (Mesoscale)...... 16 Introduction...... 16 Methods...... 16 Results...... 18 Aspects of surface sediment and mussel distribution (Microscale)...... 20 Introduction...... 20 Methods...... 20 Results...... 22 Discussion...... 23 Restoration Implications for the Umatilla River...... 27 Literature Cited ...... 30 Tables...... 35 Figures...... 48
Chapter Two: Historical distribution of freshwater mussels in the Umatilla and John Day River systems ...... 74 Introduction...... 75 Methods...... 76 Results...... 77 Discussion...... 79 Literature Cited ...... 82 Appendices...... 83
2 EXECUTIVE SUMMARY
Chapter 1: Multi-scale investigation of the distribution of freshwater mussels in the Middle Fork John Day River: implications for restoration
This study examines the distribution of mussels in the Middle Fork John Day River (MFJD) at multiple spatial scales: macro, meso and micro. Specifically, the hierarchical organization of stream features in the MFJD was explored at these habitat levels to determine how the characteristics and location of valley segments, stream reaches and geomorphic units, and surface sediment characteristics influenced freshwater mussel populations and occurrences. Three main questions were addressed with this study:
1. How were mussels distributed within the stream network (macroscale)? 2. How were mussels distributed with respect to longitudinal variations in channel types, such as pools, riffles, and runs (mesoscale)? 3. Did freshwater mussels preferentially occur in definable aspects of the surface substrates (microscale)?
In general, this study illustrates that the three genera of mussels in the MFJD River exhibit preferences for particular habitats or habitat types at all three spatial scales measured. For example, at the macroscale, mussels were distributed longitudinally – with certain areas of the channel dominated by a particular mussel species. Margaritifera were proportionally more abundant in upper channel reaches and decreased in a downstream direction. Conversely, Anodonta and Gonidea increased in numbers in a downstream direction. Gonidea was the least common species encountered in this study, and occurred only in relatively low numbers throughout the study reaches.
At the mesoscale, all three genera were positively associated with pools and runs, but were negatively associated with cascades. These negative meso-habitat associations may be related to the gradient associated with riffles and cascades. However, the variance associated with the data collected in this study is high, and gradient alone does not explain mussel distribution at the mesoscale. There does appear to be an upper gradient threshold (~ 3%), above which mussels did not occur, no matter which reach was sampled.
At the microscale all three genera were habitat generalists in regards to surface sediment characteristics. However in this study mussels were more common in areas of channel that did not contain a high percentage of fine sediments, which may indicate that interstitial porosity may be an important determinant of mussel occurrence at the microhabitat scale.
Collectively, these types of data can potentially guide restoration efforts in the Umatilla River where one species of mussel, Margaritifera falcata, has been extirpated from the system, and where the other two species, Anodonta spp. and Gonidea angulata, occur in low numbers.
3 Chapter 2: Historical distribution of freshwater mussels in the Umatilla and John Day River systems.
Freshwater mussels were historically an important food for mid-Columbia tribal peoples. Middens of freshwater mussel shells are not uncommon at historical village sites and this archeological record of harvest dates back over 10,000 years (Lyman 1984). Freshwater mussels were harvested during salmon fishing or when river conditions were favorable. In addition, mussels may have been harvested during periods when other foods sources were limited, such as late winter.
The objective of this study was to ascertain where mussels historically occurred in the Umatilla and John Day River systems. An understanding of where mussels historically occurred in a river basin can potentially aid in conservation and recovery efforts, and will aid in future efforts to restore mussel populations in the Umatilla River Basin. This historical information will be used to establish a context for the interpretation of survey data collected in 2003 and 2004, and can serve as a baseline for analyzing changes in freshwater mussel distribution in the John Day and Umatilla River systems.
Three methods were used to ascertain the historical data: interviews with CTUIR Tribal members, examination of museum collections, and reviews of available literature.
In summary, the majority of tribal members asked about the occurrence of freshwater mussels in the Umatilla River system recalled seeing mussels in the system. However, it is apparent that the use of freshwater mussels for consumption or other uses is no longer a common practice. Staff members of CTUIR’s Cultural Resources Protection Program (CRPP) reported they knew of no archival material (e.g., reports, oral histories, shell ornaments) regarding freshwater mussels in the Umatilla River upstream of its confluence with the Columbia River. However, they did report that Tribal archaeological sites (e.g., shell middens and burial sites) were known from the confluence of the Umatilla River and other areas of the Columbia River drainage.
Over 175 records of freshwater mussel occurrences from Oregon were found in the museum collections examined (Appendix 1a). An additional 108 records were found in the USDA Forest Service western mollusk database (Appendix 1b).
4
CHAPTER ONE
MULTI-SCALE INVESTIGATION OF THE DISTRIBUTION OF FRESHWATER MUSSELS IN THE
MIDDLE FORK JOHN DAY RIVER: IMPLICATIONS FOR RESTORATION
by Jeanette K. Howard, Jayne Brim Box and David Wolf
Tribal Fisheries Program Department of Natural Resources Confederated Tribes of the Umatilla Indian Reservation Pendleton, Oregon, U.S.A.
5 INTRODUCTION
Overview Over the past two decades, freshwater mussels have been the subject of numerous studies both in the United States and worldwide because of rapid population declines (Bogan 1993, Williams et al. 1993, Nott et al. 1995, Neves et al. 1997, Brim Box and Williams 2000). Yet few studies have focused on freshwater mussels in the Pacific Northwest, and little is currently known about their status, distribution, or habitat requirements in the western United States. This study (the second year of a three-year study to provide critical information on the status of freshwater mussels in the mid-Columbia) follows the 2003 efforts to investigate the status and distribution of freshwater mussels in the Umatilla and John Day River systems. It appears that two species of freshwater mussels (Margaritifera falcata and Gonidea angulata) have been virtually extirpated from the Umatilla River, while populations of Anodonta spp. remain in that system (Brim Box et al. 2003). In contrast, all three genera maintain healthy populations in a nearby watershed -- the Middle Fork John Day River (MFJD). To help facilitate the Confederated Tribes of the Umatilla Indian Reservation’s (CTUIR) recovery efforts of freshwater mussels in the Umatilla River Basin, we explored how habitat variables, measured at three geomorphologically-significant scales, were associated with freshwater mussel distributions in the MFJD River. Understanding how mussel populations vary, at multiple scales, in regards to physical features of the MFJD can potentially guide efforts to restore freshwater mussels into the Umatilla River system. Recovering native freshwater mussel populations in the Umatilla River complements CTUIR’s ongoing efforts to restore ecosystem diversity, function, and traditional and cultural opportunities in the Umatilla Basin. [Note: for the remainder of this paper, the three species will, in most cases, be referred to by the genus name only -- Anodonta, Gonidea or Margaritifera]. The conservation biology of freshwater mussels in the Pacific Northwest is of interest for several reasons. First, mussels were an important traditional natural resource for tribal peoples of the Columbia River (See Chapter 2). Mussels were utilized as a food source and their shells were used for ornamentation and as tools. Native Americans harvested freshwater mussels in the interior Columbia River Basin for at least 10,000 years (Lyman 1984). Ethnographic surveys of Columbia Basin tribes reported that Native Americans collected mussels during salmon fishing
6 (Spinden 1908, Ray 1933, Post 1938). Mussels were prepared for consumption by baking, broiling, steaming, and drying (Spinden 1908, Post 1938). The use of mussels by tribal peoples has decreased during the past 200 years, and is probably due to a combination of factors, including the decline of mussel populations and the assimilation of tribal peoples following Euro-American settlement (Chatters 1987). Mussels are an important, though often unrecognized, component of many river ecosystems. Historically mussels were the dominant consumer biomass in many river systems. As filter-feeding grazers, mussels can remove large amounts of particulate matter from the water column and transfer that matter to the substrate as biodeposits (agglutinated mussel feces and pseudofeces). Mussel biodeposits are a nutrient rich and easily assimilated food source, and probably have significant trophic relevance in many benthic communities where mussels occur Freshwater mussels are sensitive to a wide variety of watershed changes, and most species are dependent on high-quality riverine habitats. Mussels are nearly stationary, bottom- dwelling filter feeders, and are vulnerable to alterations of streambed substrates, suspended sediment concentrations, and changes or accelerations in riverbed scour and deposition (Strayer 1983, Layzer and Madison 1995, Brim Box and Mossa 1999). Watersheds in Oregon have undergone massive urbanization, large-scale hydroelectric engineering projects, water diversions, logging, and agricultural development over the past century. Habitat alterations from dams, channel modifications, agriculture and forestry practices have significantly contributed to the decline of freshwater mussels throughout North America (Williams et al. 1993, Layzer et al. 1993). These same types of alterations in the Columbia River Basin have probably affected the distribution and abundance of freshwater mussel populations, although studies documenting these causal relationships are lacking. Freshwater mussels, because they may live over 100 years, can provide insights into the timing and long-term impacts of watershed changes, especially if the causal agents that control the factors (e.g., habitat and growth) that determine population viability are understood. Freshwater mussels are dependent on fish hosts for larval stage development (Coker et al. 1921, Matteson 1955, Fuller 1974, Oesch 1984). Therefore, this resource may have been seriously affected by the decline of salmonid populations during the past 100 years within the Columbia Basin. There is little specific information about the species-specific relationships between western species of freshwater mussels and their probable host fishes. However the
7 probable host fish species for one western mussel species -- Margaritifera falcata -- includes Coho salmon (Oncorhynchus kisutch), Chinook salmon (Oncorhynchus tschawytscha), and rainbow trout (Salmo gairdneri), thereby making salmonids an integral component of viable Margaritifera populations and life history. The decline of salmon and other fish species in the Columbia Basin probably contributed to freshwater mussel declines, although this linkage has not been well documented.
2003 Survey Results In 2003 freshwater mussels were inventoried in the Umatilla River and its tributaries, and in the main stems of the Middle Fork and North Fork John Day rivers. Sites were selected to obtain a thorough and even coverage of the target rivers. Surveys were conducted where, based on habitat characteristics, there was a maximum chance of encountering freshwater mussels. Surveys were made at approximately 4 km intervals throughout the main stem of the Umatilla and MFJD rivers, and less frequently in Umatilla tributary streams and in the North Fork John Day River. The surveys were conducted using timed searches (Strayer et al. 1997, Vaughn et al. 1997, Strayer 1999, Strayer and Smith 2003). All mussels were collected by hand by snorkeling or by direct observation in shallow areas. At each site all possible habitats where mussels could occur were checked, including root and sedge mats, rock crevices, logs, and aquatic vegetation. The presence of all mussels encountered was recorded for each site. Standard field data for each site were also recorded, including drainage, locality, qualitative stream flows, time, stream dimensions and conditions. Each site was surveyed until no new species were found or all potential habitats where mussels could occur were surveyed. A minimum of one-person hour was spent at each site. A total of 17,000 mussels were counted from 92 sites during the 2003 survey, although this number reflects only a fraction of animals encountered. All three genera of mussels (Anodonta, Gonidea and Margaritifera) known for the western United States were found. Of the specimens counted, approximately 65% of mussels were Margaritifera, 27% were Anodonta, and 8% were Gonidea. Mussels were rare in the main stem and tributaries of the Umatilla River, found at only six of the 55 total sites sampled (Table 1). Only two genera, Anodonta and Gonidea, were found in the Umatilla Basin. We concluded from the survey results that Gonidea
8 populations in the Umatilla were not recruiting as only four large individuals were encountered (Table 2). No live Margaritifera were found, although at one upstream site numerous shell fragments were scattered on the floodplain. In contrast to the Umatilla River, mussels were common in the Middle and North Fork John Day rivers, where at least one mussel specimen was found at every site sampled. All three genera were found at nearly half of the sites surveyed on the MFJD and at 15% of the sites on the North Fork John Day (Table 1). The total number of mussels counted in the Middle Fork and North Fork exceeded 17,000 animals (Table 2). Given that these counts were obtained during timed searches, these counts are most likely but a small fraction of the total number of mussels in the two rivers.
Research Approach and Objectives Stream systems are organized hierarchically and exhibit top-down controls on the expression of habitat features (Frissell et al. 1986). These levels of hierarchical organization, which have been long recognized by fishery biologists as influencing the distribution and abundance of salmonid species in the Pacific Northwest, include valley segments, stream reaches, and channel geomorphic units. The characteristics of each of these levels are constrained by the physical processes that operate at the next highest level. For example, stream reaches are controlled by longitudinal profile and slope, whereas individual channel geomorphic units (pool, run, riffle, cascade) are controlled by the capacity of the reach to produce, transport and store sediments (Frissell et al. 1986). Unlike the Umatilla River system, where mussel populations are diminished in numbers, diversity and occurrence from historical levels, the MFJD contains reproducing populations of all three genera of freshwater mussels found in the western United States. Understanding the factors, expressed at different scales, that control mussel distributions and abundances in the MFJD can ultimately aid in the restoration of freshwater mussel resources in the Umatilla River system. In this study, the distribution of mussels in the MFJD system was examined from three hierarchical habitat levels -- macro, meso and micro. Specifically, the hierarchical organization of stream features in the MFJD was explored at these habitat levels to determine how the characteristics and location of valley segments, stream reaches and geomorphic units influenced
9 freshwater mussel populations and occurrences. The distribution and abundance of freshwater mussels is likely due to a culmination of physical processes that operate at these three spatial scales. The objective of this study was to provide a multi-scale treatment of factors influencing freshwater mussel distribution, species composition and abundance in selected reaches of the MFJD. In this study, the hierarchical organization of stream features in the MFJD was explored to determine how the characteristics and location of valley segments, stream reaches and geomorphic units influenced freshwater mussel populations and occurrences. Specifically, three questions were addressed: 1. How were mussels distributed within the stream network (macroscale)? 2. How were mussels distributed with respect to longitudinal variations in channel types, such as pools, riffles, and runs (mesoscale)? 3. Did freshwater mussels preferentially occur in definable aspects of the surface substrates (microscale)?
STUDY AREA
This study was conducted in a 35-km section of the MFJD where all three genera of western mussels are known to occur (Brim Box et al. 2003) (Figure 1). The MFJD is part of the John Day River system, the largest watershed in the mid-Columbia basin. The MFJD has a total watershed area of 2000 km2, and an elevation range of 670 to 1700 m. The channel in the study area is sixth order, and the mean gradient is 0.6 % but is highly variable on the scale of 10 to 100 m (See Network Distribution results below). Vegetation in the watershed is primarily Ponderosa pine (Pinus ponderosa) and grand fir (Abies grandis). Various land uses and resource extraction, such as road building, grazing, logging and placer mining continue to affect river habitats (Torgersen 1999). Although large- scale dredge mining ended in the 1940s, mine tailings are visible and continue to impact the river channel within the mid-reaches of the MFJD (Torgersen 1999). The hydrology of the John Day Basin is characterized by high spring runoff from winter snowmelt and spring rains (Figure 2). The hydrologic consequence is a seasonal predictable cycle of flooding in spring months (April and May) and near drought in summer (Figure 2) (US
10 Geological Survey 73-year period (1929-2002)). Peak runoff usually occurs in April and May with mean flows of ~ 20 m3/s, while mean low flows usually occur in August and September (~ 1 m3/s) (Figure 2). The largest floods on record occurred in January 1965 and January 1997 with discharges of 123 m3/s and 111 m3/s, respectively. The John Day River is important for fishery resources in the Columbia Basin because it lies upstream of only three of the Columbia River dams (Bonneville, the Dalles, John Day Dam), and is one of the longest free-flowing rivers in the United States (McDowell 2001). Anadromous steelhead and bulltrout, both federally listed as threatened, are found in the MFJD, and spring Chinook, a species of special concern, uses sites within the study area for spawning, rearing and as holding habitat (Torgersen et al. 1999, McDowell 2001).
MULTI-SCALE PERSPECTIVE ON MUSSEL DISTRIBUTIONS
I. Network Distribution and Species Composition (Macro-scale)
Introduction Stream channel systems can be considered hierarchical in nature, as nested morphological units that increase in spatial scale from an individual geomorphic unit to the channel network at large (Frissell et al. 1986, McDowell 2001). In this study, reaches were designated as channel sections based on changes in valley width, tributary confluences and cultural features (e.g., bridges, mine tailings, land uses) as per McDowell (2001). The analyses of freshwater mussels in the MFJD examined the location, species composition and abundance of mussels in relation to valley segment type, changes in channel planform (lateral channel movement and sinuosity) over time, and large-scale longitudinal variation in channel gradient. Valley segments are distinct sections of the stream channel network (Bisson and Montgomery 1996). This study was located in the alluvial valley of the MFJD, an area of channel that is supplied with sediments from upstream sources and is capable of moving and sorting sediments at “erratic intervals” (Bisson and Montgomery 1996). Within this alluvial valley segment, channel areas can be categorized into smaller scale reach classifications (Table 3). By examining the network-wide distribution of mussels in this alluvial
11 segment, information was obtained on the reach types most closely associated with the distribution of the three target mussel species.
Methods – Macroscale Reach Selection The sample reaches chosen for this study were delineated from information contained in McDowell (2001), and data collected during 2003 (Brim Box et al. 2003). Sample reaches were chosen based on the following two criteria; the three genera of mussels occurred in that reach, and land uses and direct channel modification varied among the chosen reaches. A total of six reaches, labeled A (downstream) to F (upstream), were selected on the main stem of the MFJD (Table 4). The reaches were located between river kilometer 50 and 85. River kilometers were calculated from a digital elevation model (DEM) analysis of the river system (see below).
Mussel surveys Field surveys were conducted during the summer of 2004 to document, quantitatively, the occurrence of mussels within the six study reaches. Continuous sections of channel were systematically surveyed to map the abundance and species composition of mussels that occurred in each reach. The length of channel surveyed varied in each reach because each reach length varied (Table 4). Surveys were conducted primarily by snorkeling, although in very shallow areas (e.g., < 10 cm in depth) mussels could be detected without snorkeling. Reaches were divided into geomorphic units (pools, riffles, and runs) for the mussel surveys, and surveys began at the downstream end of each unit. Units were surveyed systematically by moving through the unit in parallel transects, approximately 2 meters apart, until the entire geomorphic unit was searched. Mussel surveys were conducted during summer months when flows were low, visibility was high, and turbidity was minimal to maximize the number of mussels that could be detected using visual surveys. Although buried mussels may be missed during visual searches, visual surveys are effective if done by snorkeling when water clarity is high and flows are low. All mussels found in each unit were counted and identified to species based on shell morphology and features of the mantle margins. If the surveyor was unable to determine the species by visual inspection, the mussel was removed from the substrate, identified and returned
12 to the same location. Mussel survey data were incorporated into the GIS using the georeferenced coordinates based on the location of mussels within the reach.
Reach Characteristics DEM Analysis A routed channel network within the entire MFJD Basin was delineated using 10-meter digital elevation models (DEMs) obtained from the Oregon Geospatial Data Clearinghouse (http://www.oregon.gov/DAS/IRMD/GEO/sdlibrary.shtml) and numerical programs developed by the Earth Systems Institute (Miller 2002, 2003). DEM data were also used to generate a routed channel network for the Umatilla River but were not used in this analysis. Additional channel and valley attributes estimated included stream order, drainage area, channel gradient, channel length, valley width and side-slope gradient. The programs developed by the Earth Systems Institute are divided into two primary modules, Bld_grds and Netrace. Bld_grds is a multiple-flow direction algorithm. In this module, the flow direction and upslope contributing areas are calculated for every DEM pixel, and provides an estimate of the amount of flow (based on gradient) that drains into adjacent cells. Netrace incorporates the output files created by Bld_grds to trace a routed channel network, determined by flow directions and tributary connections, and estimates topographically-controlled channel and valley attributes. Details of these algorithms and models are discussed in Miller (2002, 2003). From these generated data, the average stream gradient and valley width per reach were calculated, and a stream concavity profile was developed for the MFJD. The DEM and reach- level mussel data (location, species composition and abundance) were used to examine relationships between channel attributes and the network-wide distribution of mussels. In addition, the gradients generated from the DEM analyses were compared to the reach-scale classification of gradients designated by Bisson and Montgomery (1996) (Table 3), in order to investigate the associations between mussel species distributions and reach characteristics.
Sinuosity Changes in channel planform were investigated in reaches D, E and F using scanned and rectified 1939 and 1990 aerial photos provided by Patricia McDowell at the University of Oregon. Aerial photos were not available for reaches A, B and C. The channel of the main stem
13 MFJD for the two time periods was digitized from the rectified images and included those reaches that fell within the extent of the aerial coverage that was available. Changes in channel planform between 1939 and 1990 were used to determine changes in sinuosity in the section of reaches surveyed for mussels. Sinuosity (S) was calculated as:
channel length (m) S = straight - line valley length (m)
Results – Macroscale Mussel survey A total of 11.3 km of mainstem MFJD was surveyed for mussels and large-scale reach characterization. The relative abundance and density of mussels varied between reaches (Figure 3). For example, the average highest density of Margaritifera found per meter of channel length was in reach F (0.4 mussels per meter), the average highest density of Anodonta found per meter was in reach B (0.9 mussels per meter), and the average highest density of Gonidea was found in reach A (0.2 / meter) (Figure 3). For all three species combined, the average highest density of mussels occurred in reach B (1.3 mussels per meter of channel length). The distribution of individual mussel species varied longitudinally and was reflected in changes in relative abundance for each species across the six reaches that were surveyed (Figure 4). For example, Margaritifera was more common than Anodonta or Gonidea in the upper reaches (E and F) and accounted for over 90% of the mussels found in those reaches (Figure 5). Progressing downstream, the relative abundance of Margaritifera decreased, from 40% in reach D, to 25% or less of the mussels encountered in reaches A, B, and C (Figures 4& 5). Conversely, Anodonta were relatively rare in reaches E and F, while Gonidea were absent. However, in the downstream reaches (A, B and C) Anodonta accounted for 60%, 70%, and 80% of the animals found. Gonidea were also absent from reach D, but were found in reaches C, B, and A. The relative abundance of Gonidea (as well as the number per m of channel sampled) increased progressively downstream, with Gonidea comprising 2% of the mussels found in reach C, 7% in reach B, and 15% in reach A (Figures 4 & 5). Based on observations made during the 2003 mussel survey, it was known that all three species were patchily distributed in the MFJD, and that the distribution and abundance of each
14 species varied independently and longitudinally from the headwaters to the confluence (Brim Box et al. 2003). Similarly, in this study the total number of mussels per channel meter surveyed increased downstream, with the highest densities recorded from reaches A and B (> 1 mussel found per meter of channel surveyed). The patchiness of mussel occurrences and abundances was illustrated by the low number of mussels encountered in the middle reaches of this study -- C and D -- where only 0.3 and 0.2 mussels were found per meter surveyed, respectively.
Reach Characteristics DEM analysis From the DEM analysis, a routed channel network was obtained that included mean, maximum, and minimum gradient, and the alley width per 50-meter reach of channel (Table 5). This routed network provided a template by which to examine the distribution of mussels along the channel gradient (Figure 6). This study occurred in the middle section of the MFJD where the gradient, or slope, was highly variable (Figure 7). For example, although the mean gradient for the entire channel network was 0.8% (the median was 0.6%) the gradient varied from 1.0% to 0.3% between the six reaches of this study (Table 5). In addition, within a particular reach the gradient could be highly variable or alternatively, highly consistent. For example, in reach B the slope ranged from 0.03% to 2.8%, but in reach C the slope ranged only from 0.01% to 0.05%. Based on previous reach scale classification schemes (Table 3) it appears that the majority of the MFJD mainstem included in this study could be classified as pool-riffle. However, in reaches B and D, there are sections of channel with slopes >2%, which based on the classification scheme, fall within the plane-bed classification (Table 3 and Figure 6). These classifications did not appear to be strongly correlated with the occurrence of freshwater mussels, in that mussel abundance was lowest in reach D and highest in reach B. Therefore, it appears that mussels occur in both pool-riffle and plane-bed reach types. Valley width also varied between study reaches. Reaches D and E could be considered wide-valley reaches (Table 5). In general, wide-valley reaches are likely to be dominated by pool-riffle sequences, more fully-developed meanders, broader floodplains, and habitat heterogeneity, while narrow reaches tend to contain more plane-bed areas (McDowell 2001). However, human modifications (road encroachment, rip rap, channel straightening) have caused
15 reaches E and D to respond as narrow-valley segments, confined to a controlled river channel (McDowell 2001). Therefore, in terms of stream function, all six reaches could be considered narrow valley reaches.
Sinuosity From digitized aerial photographs it appears that sinuosity decreased 13% in reach D and 25% in reach E between 1939 and 1990 (Table 6). This change is attributed primarily to an increase in channel straightening and dredge mining between the two time periods (McDowell 2001). Sinuosity remained relatively unchanged in reach F, with a minor increase of about 2%.
II. Reach-level channel types and mussel distributions (Mesoscale)
Introduction In streams systems, mesoscale physical habitat channel units (i.e., pool, run, riffle, cascade) are known to be important controlling factors for aquatic organisms. For example, cascades and riffles are important re-aeration areas for fish and invertebrate production and spawning (Bisson et al. 1982, Bisson and Montgomery 1996). Geomorphic units with lower velocities, such as runs and pools, provide resting and holding habitat for fishes (Bisson et al. 1982, Bisson and Montgomery 1996) and may provide refuge for freshwater mussels in river systems (Howard and Cuffey 2003). These mesoscale habitat features, or geomorphic units, are associated with specific gradients, velocities, and shear stresses. They are important for the survival and reproduction of long-lived organisms, like freshwater mussels, especially in highly variable stream environments (Howard and Cuffey 2003). In this study mussel distribution was examined with respect to the structure and longitudinal variation of pools, riffles, runs and cascades within the six study reaches.
Methods Channel geomorphology The fine-scale topography of the study reaches was measured using a surveyor’s rod and a TopCon surveying station. These topographic surveys were designed to document the fine- scale changes in gradient (slope) and the location of individual geomorphic units within each
16 reach. Geomorphic units were categorized as four types: cascades, riffles, runs or pools. The variation in velocity was pronounced between cascades, riffles, runs and pools in the study area, with velocities in pools and riffles typically being 0.05 and 0.5 m/s, respectively. The velocity of runs fell between pools and riffles, and cascades were > 0.5 m/s. Cascades and riffles were considered turbulent whereas runs, although of higher velocities than pools, were not turbulent. Runs were easily distinguishable from riffles as areas with greater depths and less turbulent flows. In general it was not difficult to visually distinguish between these meso-habitat types. Slope for each geomorphic unit was calculated by dividing the change in elevation per geomorphic unit by the length of that unit. In general slope should be lowest in pool habitats and highest in cascades. Geomorphic maps were constructed of water surface elevations, channel bed topographies, and types of geomorphic unit. Dimensions of each geomorphic unit (length, width, maximum depth) were directly measured during summer months. All units were georeferenced with a global positioning system (GPS). Using an ArcView geographic information system (GIS), the location of all geomorphic units was incorporated into a spatial database. The mussel survey data were also incorporated into the GIS using the georeferenced coordinates, based on each geomorphic unit channel type, and the location of mussels within the geomorphic unit. This provided a snapshot of the location and relative abundance of mussels in each geomorphic unit within each reach.
Mussel Densities The mussel survey data were used to calculate the total linear density (number of mussels per meter length of channel) within each geomorphic unit using the length of each geomorphic unit and the number of mussels found in that unit. Linear densities, instead of areal densities (number of mussels per square meter), were used in this study because mussel distributions in the study reaches were concentrated near the banks, and were not uniformly distributed across the channel.
Habitat Associations The preferential use of resources by mussels can be determined by comparing the use of a particular channel unit type with the availability of that channel unit type. To compare the
17 distribution of mussels among channel types, the Strauss (1979) linear selection index was used. This index measures the degree to which organisms select particular resources (i.e., channel unit type) in relation to the range of those resources available to the organisms. The selection index (L) is calculated as:
L = ri − pi
where ri represents the relative proportion of the total population of that species found in habitat
type (i); and pi is the relative proportion of habitat type (i) in the stream reach. The index ranges from –1.00, indicating a habitat is abundant but completely avoided by a particular species, to +1.00, indicating a habitat that is rare is used exclusively by a species. A value of 0 indicates that the habitat is used in about the same proportion as its abundance.
Results Channel geomorphology and mussel occurrence A total of 5,263 mussels were counted from 179 geomorphic units (Table 7). Riffles and runs occurred in roughly the same percentages, and were the dominant channel types, accounting for 88% of all geomorphic units surveyed (Figure 8). Pools and cascades were much less abundant, although similarly represented, with each accounting for about 6% of the geomorphic units surveyed. Mussel densities varied with geomorphic units, but within a particular geomorphic unit, mussel densities were similar across the six reaches (Table 7). For example, mussel densities tended to be highest in pool meso-habitats, regardless of the reach surveyed (Figure 8 & Table 7). All three mussel species occurred in pool habitats in higher densities than other meso- habitats, followed by runs, riffles and cascades (Figure 8 & Table 7). Some evidence of habitat partitioning was found in this study. For instance, although less commonly found than in the other three meso-habitat types, over 50 Margaritifera were found in cascades, while only two Anodonta and no Gonidea were found in that habitat type. In addition, Margaritifera occurred in riffles in densities that were 3 to 5 times higher than the other two genera (Table 7). In general, all three species occurred in river stretches with the lowest average channel gradient, suggesting that the distribution of mussels in the MFJD is related to fluvial geomorphology (Figures 9-14). For example, in reaches A and B, the areas with the lowest gradients contained the greatest number of mussels (Figures 9 and 10). However, the
18 distribution of mussels did not appear to be gradient-dependent in all reaches, especially reaches C and D where, in some cases, mussels were also common in areas of moderate gradient (Figures 11 and 12). Mussel occurrence at the mesoscale appeared to be a result of both the longitudinal position of the reach as well as the gradient found within a reach. In general and across the six reaches, mussels appeared to prefer lower gradient areas of the channel, regardless of the reach in which they occurred (Figures 15 through 20). This pattern appeared to be species-dependent, however. For example, Margaritifera occurred in higher gradient areas of a reach than Anodonta or Gonidea, especially in upstream reaches (E and F). Mussels were more common in areas of low gradient, and there appeared to be an upper gradient threshold (~ 3%) above which mussels did not occur (Figure 21). Margaritifera occurred in higher slope areas than the other two genera, but not in areas above a 3% gradient. Anodonta and Gonidea were concentrated in areas of the channel where slopes were generally < 1%. This may explain why Anodonta and Gonidea were concentrated in the lower reaches of the channel – headwaters are higher slope regions of the channel than the mid-reaches. As expected, geomorphic channel units were closely correlated with gradient, in that slope was greatest in cascade reaches (ranging from 1.5 to 7 % gradient), lowest in pools (ranging from 0 – 1% slope) (Figure 22), and ranged from 0 to 7% in riffles, and 0 to 2% in runs. All three mussel species showed some preferential use of channel unit type (Figure 23) although in most cases, distribution in geomorphic unit types varied by reach. For example, all three species were, in most cases, both positively and negatively associated with a particular geomorphic unit, depending on which reach was surveyed (Figure 24). Alternatively, there were some cases where the preferential use of geomorphic units was evident. For example, based on the Strauss linear selection index, Gonidea appeared to occur less frequently in runs, although this geomorphic unit type was common in all six study reaches (Figure 24). In all reaches except C, all three species of mussels (if they occurred) were positively associated with pools. Additionally, all three species had negative or neutral associations with riffle and cascade habitats except in reach C, where there were positive associations with those channel types (Figure 24). Reach C is a long, channelized section of river with the lowest mean gradient (0.3%) of any reach surveyed (Table 5). Therefore the riffles in this reach have lower gradients than other reaches. In addition, the pools in this reach were created from low elevation rock
19 dams and are not naturally occurring pools. This may explain why, in reach C, associations between mussel occurrences and channel unit types were the opposite of the associations found in the other five reaches.
III. Aspects of surface sediments and mussel distributions (Microscale)
Introduction Subsets of geomorphic units within three reaches (A, B, and F), where mussels were most common, were selected to examine microhabitat characteristics and aspects of mussel species distribution and population structure. The subsets of geomorphic units that were chosen for microhabitat characterization contained the highest densities of mussels encountered in the three study reaches. A total of six geomorphic units were selected -- three runs in reach A, a pool and a run in reach B, and one pool in reach F.
Methods Within the selected geomorphic units, microhabitat sample areas were determined by mussel presence. Thus the total area sampled in each geomorphic unit varied, depending on the dimension of the designated mussel “bed.” At each unit, beginning at the most downstream section of the delineated area and working upstream, quadrats (0.25 m2) were placed haphazardly on the river bottom and the specific location of that quadrat was recorded. All mussels falling within or touching the sides of a quadrat were identified to species, measured to the nearest 0.5mm, weighed to the nearest milligram, counted, and returned to the quadrat. Aspects of the surface sediments, as well as the presence of aquatic vegetation, were also recorded. For each geomorphic unit, a sufficient number of quadrats was used to ensure that at least 10% of the designated area was sampled. There are no standard methods of characterizing surface sediments in freshwater streams in ecological studies (Bovee 1982, Gordon et al. 1992, Strayer and Smith 2003). A general classification of surface sediment composition, expressed as a percentage, was recorded from visual observations of the surface sediments of each quadrat. Classification of individual sediment classes was based on the Wentworth scale and included the following sediment size categories: bedrock, boulder (>250 mm), cobble (60--250 mm), gravel (2--60 mm), sand (2--
20 0.063mm) and fines (< 0.063). In addition, the presence of sedge root mats (Carex nudata) or milfoil (Myriophyllum sp.) was recorded. Species-specific associations between mussels and surface sediment characteristics were explored by examining whether the presence of mussels was related to aspects of the substrate properties, including mean particle size, sorting, and the proportion of sand and/or fines present in a quadrat. We used categorical data (e.g., whether substrates were well or poorly sorted) (Table 8) for these substrate properties because surface sediments in each quadrat were based on visual classifications and not physical counts or weights of each sediment particle class. This approach was more conservative than relying on the visual estimates of percentages of each substrate particle class recorded. Sediment sorting in this analysis was based on the observed variation and percentage of substrate classes observed, as well as the estimated mean sediment class, rather than from a value obtained from the standard deviation of a substrate sample divided by the mean particle size (Lindholm 1987). Sorting provides a measure of the spread of sediment sizes within a particular substrate or quadrat sample (Gordon et al. 1992). Sediment sorting can be ecological meaningful in that sorting is positively correlated with porosity (Brim Box 1999), and therefore well-sorted sediments generally contain more interstitial areas than poorly-sorted sediments. The species-specific associations between mussels and aspects of surface sediments were explored statistically by examining if the presence of mussels was associated with 5 characteristics of each quadrat: mean particle size, sorting, fraction of sand and/or fines present, and the presence of vegetation. Analyses of niche breadth were used to determine whether each mussel species present was a habitat specialist or generalist, in relation to the mussel beds sampled. In general, niche breadth measurements are used to examine how a species in one population utilizes niche parameters (e.g., surface sediment characteristics) compared to other populations (Krebs 1989). Measurements of niche breadth are obtained by observing the distribution of a target species within various resource states. Resource states reflect variations of resource availability (e.g., large mean sediment particle sizes and a lack of fines in a quadrat). Each unique combination of the five factors measured in each quadrat was considered a resource state. In this study, resource states were based on aspects of the surface sediments described above. The amount of niche overlap was determined using Smith’s Measure (Smith 1982),
21 which takes into account resource availability and varies from 0 (minimum niche overlap) to 1.0 (maximum niche overlap). An analysis of niche overlap was used to investigate how mussel communities in the target reaches were organized in regards to resource use (as defined by the same resource states used to measure niche breadth). There is no single best measure of niche overlap (Krebs 1989). In this study, niche overlap was determined using two metrics; a) the percentage overlap and b) Hurlbert’s Index. These indices were used to measure the degree of niche overlap between the three species of mussels encountered. The percentage overlap index is expressed as a percentage of overlap between species j and species k. It is one of the simplest measures of niche overlap because it measures the area of overlap of the resource utilization curves for two species (Krebs 1989). An advantage of this measure is that it is not sensitive to how the resource states are divided. Hurlbert’s Index was also used because unlike other measures of niche overlap, it takes into account that resource states may vary in abundance, as was found in this study. Hurlbert’s Index provides a measure of the frequency with which two species use a resource state, by examining whether the frequency of encounter between two species is higher or lower than expected, given the availability of a particular resource state (Hurlbert 1978). For example, Hurlbert’s Index is 1.0 when two species utilize each resource state in proportion to that resources abundance, 0 when two species do not share any resources, and greater than 1.0 if two species use certain resources more intensively than other resources, and their resource preferences are similar (Krebs 1989). Differences in the mean size of mussel species between reaches were statistically assessed using a one-way analysis of variance (ANOVA). A posteriori comparisons between reaches were made with Tukey’s test.
Results Microhabitat associations A total of 686 mussels were found in the 214 quadrats sampled (Table 9). A total of 37 unique resource states were identified (Appendix 1). Based on these resource states, all three species showed little habitat preference, as the niche breadth for each species in each reach (where they occurred) was > 0.9 (Table 10). In other words, given the availability of unique
22 resource states or habitats, none of the species in this study showed a preference for a particular microhabitat type. The amount of niche overlap between Anodonta and Margaritifera was 1.138, between Anodonta and Gonidea it was 1.156, and between Margaritifera and Gonidea it was 1.079. This suggests that all three species use certain resource states more intensively than others and that these preferences coincided among the three species. Four resources states accounted for nearly 40% of the habitat where Anodonta were found, and over 50% of the habitats where Margaritifera and Gonidea were found (Table 11). These resource states, in general, represented surface sediments that contained medium to large particle sizes, a low percentage of fine sediments and sand, and in most cases, no vegetation. However, a low percentage of fine sediments was the only characteristic measured that was found in each of the four resource states where these three genera were most commonly found.
Mussel lengths There were significant differences (α = 0.05) between the average length of mussels collected from the three study reaches (Table 12). Anodonta were significantly smaller in reach B than in reaches A or F. The average length of Margaritifera was significantly different in each reach, as were Gonidea. For all three species, the average shell length was significantly less in reach B, and it appears that the average size of mussels encountered in reach B was significantly smaller for all three species. An ongoing study of length-age relationships, based on shells collected from these study reaches, should provide a nexus for examining the age structure of these populations. In addition, the presence of muskrat shell middens in reach B suggests that predation may be a controlling factor of population structure in that reach. Shells collected from those middens are currently being measured, cross-sectioned and aged.
DISCUSSION
Overview Past studies of mussel distributions and abundances have illustrated the difficulty of choosing the physical properties of a river system that are important to measure in order to illicit
23 meaningful relationships between mussel occurrences and habitat. Conventional measures of habitat variables, especially at the microscale, have not always provided the predictive power necessary to assess the occurrence or density of freshwater mussel species. In this study, a multi- scale approach was used to assess mussel distributions and occurrences. The data collected using this approach are additive, in that they can potentially and hierarchically reduce the variability inherent in predicting where mussels occur in a river system. With this approach, the information collected at each scale augments the information collected at the other two scales, and potentially can give a more complete picture of the factors that determine mussel distribution in the MFJD. This information, in turn, can aid efforts to restore mussels to the Umatilla River system.
Network Mussels were not uniformly distributed between or within study reaches in the MFJD, a result consistent with other studies that examined mussel distribution patterns (Layzer and Madison 1995, Haag and Warren 1998, Strayer 1999, Howard and Cuffey 2003). Instead, mussels in the MFJD were clumped and patchily distributed. The negative binomial distribution of mussels in the MFJD appears to be controlled across multiple, physical scales. For example, at the macro- or network-wide scale, mussels were distributed longitudinally – and certain areas of the channel were dominated by a particular mussel species (Figures 4 and 5). Margaritifera were proportionally more abundant in upper channel reaches and decreased in a downstream direction. Conversely, Anodonta and Gonidea increased in numbers in the downstream direction. Gonidea was the least common species encountered in this study, and occurred only in relatively low numbers throughout the study reaches. These results are consistent with a previous survey (Brim Box et al. 2003) that showed that Gonidea were much more common in the lower MFJD than in the reaches examined in this study, and this pattern has been observed in other western river systems (Howard and Cuffey 2003). The longitudinal distribution of freshwater mussels in the MFJD may be partially explained by food availability. Bauer (1991) suggested that distributional differences between the superfamilies Margaritiferidae (which contains the species Margaritifera) and Unionidae (which contains Anodonta and Gonidea) could be linked to food supply. Bauer (1991) found that Margaritifera had a lower metabolic rate than other species of freshwater mussels and hence
24 could grow in rivers with lower primary productivity rates. In contrast, Anodonta and Gonidea may require a richer food supply because they have higher metabolic rates. These differences in food requirements could be correlated with the longitudinal food availability in a stream system. For example, energy inputs change as streams widen in the downstream direction. Because shading and the contribution of allochthonous materials decreases, and the amount of sunlight reaching the streambed increases, algal primary productivity increases from upstream to downstream (Vannote et al. 1980). Perhaps the spatial occurrence of Anodonta and Gonidea in the MFJD can be explained, in part, by their higher metabolic rates (relative to Margaritifera) and the differences in food availability in various stream reaches. Another explanation for this longitudinal distribution could be the spatial distribution of possible fish hosts and water temperature. Torgersen et al. (2005) found the spatial structuring of fish assemblages in the MFJD exhibited a pattern of cold- (Salmonidae) and coolwater (Cyprinidae-Catostomidae) fish assemblage zones, with coldwater fishes occurring in the upstream reaches and coolwater fishes in the downstream reaches. If the three mussel species use different host fishes, as probably occurs (see Brim Box et al. (2003) for a review of host fish information), then the distribution of mussels in the six study reaches could be due to the superimposed distribution and availability of potential host fishes within these reaches. This assertion should be tested in future studies.
Mesoscale All three species of mussels were positively associated with pools and runs, but were negatively associated with cascades. These negative meso-habitat associations may be related to the gradient found in riffles and cascades, which in turn may cause mussels to be displaced during high flows or may impede juvenile settlement. Higher gradients are associated with higher shear stresses which may play a role in dislodging mussels during high flow events (Strayer 1999, Howard and Cuffey 2003) In all reaches except C, the distribution of the three genera was positively associated with pools. In reach C very little pool habitat remains in the channel areas surveyed, and constituted only 3.5 % of the habitat in that reach. Loss of sinuosity, due to channel straightening over the past 65 years, may have resulted in a decrease in both the number and type of pools found in this section of the MFJD (McDowell 2001). Efforts are currently underway to remove channel
25 straightening structures (riprap) in some areas of the channel – particularly on the Nature Conservancy lands located between approximately river kilometers 53 and 57. This may add to channel complexity and increase the number of pools in the reach. In general, mussels in the MFJD tend to be located in areas of low channel gradient, which have been reported from other western river systems (Howard and Cuffey 2003). However, the variance associated with the data collected in this study is high, and gradient alone does not explain mussel distribution at the mesoscale. There does appear to be an upper gradient threshold (~ 3%), above which mussels did not occur, no matter which reach was sampled. Although Margaritifera were patchily distributed in all gradients < 3%, Anodonta and Gonidea were generally more common in channel sections with gradients < 1%. These results indicate that reach-scale habitat structuring may be an important consideration when assessing mussel populations. These results also illustrate that alterations in reach-scale habitat structures, as exemplified in reach C, may affect mussel population structures.
Microscale Thirty-seven unique resource states or habitats were identified in this study. All three mussel genera were found in most (i.e., Gonidea), if not all (i.e., Anodonta and Margaritifera) of these resource states, suggesting that the niche breadth of all three genera is wide. Therefore, all three genera can be considered habitat generalists in regarding to the microhabitat variables measured in this study. This is not surprising, in that these genera are found across a wide geographic area of the western United States, and have been reported from a variety of habitats (Taylor 1981, Clarke 1981). That all three genera overlapped in regards to which combination of surface sediment types that did occur in is surprising, in that the habitat requirements of Margaritifera have often been reported to be different than those for Anodonta or Gonidea. For instance, Anodonta are often reported from areas that contain primarily mud, while Gonidea have been reported from sandy areas, and Margaritifera have been reported from sand to cobble and boulder-dominated substrates (Bonnot 1951, Clarke 1981, Vannote and Minshall 1982). The seeming co-occurrence of mussel species in this study may have more to do with sediment porosity and/or sorting than aspects of sediment particle size. In general, well-sorted sediments contain more interstitial pore
26 space than poorly-sorted sediments. In this study, mussels were more common in quadrats that did not contain a high percentage of fine sediments, which may also indicate that interstitial porosity may be important at the microhabitat scale. However, these assertions will need to be tested before more meaningful, or predictive, relationships between surface sediment properties and freshwater mussels in the MFJD or Umatilla River systems can be ascertained. In future studies, other microhabitat characteristics may be more useful to measure than aspects of surface sediments. For example, others have suggested that substrate stability, not composition, is important in predicting mussel occurrence (Sickel 1982, Kat 1982, Neves and Widlak 1987). Kat (1982) suggested that streambeds can be divided into high- and low-quality microhabitats. High-quality microhabitats are characterized by stable substrates and protection from scour; low-quality microhabitats are characterized by unstable substrates and a significant reduction of energy input available for growth and reproduction. Hydrologic variables such as the type of stream flow or shear stress may be more useful than substrate composition in predicting mussel occurrence (Layzer and Madison 1995, Di Maio and Corkum 1995, Howard and Cuffey 2003). Since this study began in 2003, we have noticed an increase in muskrat predation in reach B, with large shell middens located outside muskrat burrows (Brim Box and Howard, personal observation). For all three species, the mussels measured in this reach were significantly smaller than the other two reaches. It is possible that muskrats are preying on the larger mussels in reach B, and have influence the age structure of those mussel beds (i.e., they now are skewed towards smaller, younger individuals). An analysis of age calculations, based on shell cross-sections and lengths, is currently in progress, and should provide insight into the age structure of mussel populations in the study reaches, as well as insights into whether muskrat predation in reach B has affected the age population of all mussel species found in that reach.
Restoration Implications for the Umatilla River In order to conserve and recover freshwater mussel species, it is often advantageous to draw inferences between where mollusks occur and habitat parameters that influence their distribution. Unfortunately there is a paucity of studies (e.g., Huehner 1987, Bailey 1989) that have empirically tested for species-specific habitat preference and specificity, although habitat- specific sampling is often required to adequately determine invertebrate production and function
27 in streams (Smock et al. 1992). In addition, many populations of freshwater mollusks are dispersed and rare (e.g., in the Umatilla River), and therefore future studies of mollusk-habitat associations may be more effective if they consider novel sampling designs. In addition, the results of this study suggest that, because the factors that influence mussel abundance and distribution occur at multiple, physical scales, that sampling designs and efforts take into account and utilize these scales. Freshwater mussels may be moved from one place to another for conservation, management or restoration purposes. In most cases, the specific habitat requirements of individual mussel species are not known, especially at multiple scales. In addition, specific habitat parameters are rarely quantitatively measured at the site where mussels are released, but rather are based on observational or descriptive criteria (Cope and Waller 1995). Studies have shown that if species-specific site selection criteria are developed using quantitative information, they can enhance the survival of relocated mussels (Hamilton et al. 1997). However, these types of data are rarely collected, even though it has been recognized that relocation projects can be more successful as both conservation and management tools if criteria for selecting suitable relocation sites were developed (Cope and Waller 1995). Therefore, the restoration of freshwater mussels into the Umatilla River system should be based, in part, on habitat parameters that are measured quantitatively at multiple scales. The data collected in this study represent a first attempt to collect quantitative information at three spatial scales that can potentially guide efforts to restore freshwater mussels into the Umatilla River system. Whether individual mussel species are habitat specialists or generalists has generally been overlooked in relocation efforts (Hamilton et al. 1997). In general the specific habitat requirements for Anodonta, Gonidea and Margaritifera are not known. In this study all three species showed preferences for particular habitats or habitat types at all three spatial scales measured (Table 13). For example, Margaritifera were relatively more common in upper river reaches than lower reaches, were more common in pools and runs than cascades, occurred in channel areas with up to a 3% slope, and showed some habitat preference at the microscale level (e.g., was less common in quadrats that contained a high percentage of fine particles) (Table 13). Both Anodonta and Gonidea were most common in habitat units with low velocities (pools), low gradient reaches (<1% slope), and were most common in the lower
28 reaches of the area surveyed. Collectively, these types of data can be used to guide restoration efforts in the Umatilla River In addition to the physical data collected in this study, additional types of data may also aid in the restoration of mussels in the Umatilla River. For example, information on fish hosts and specific food requirements are needed. A holistic approach to mussel restoration and conservation, that takes into accounts aspects of the physical habitat, as measured in this study, as well as additional life history requirements, is most likely to advance the reintroduction of this important, though often unrecognized, component of western river systems.
ACKNOWLEDGEMENTS
We thank Patrick Luke, Byron Morris and Donna Nez and for their valuable assistance in the field, and David Close for his technical guidance and support. We thank Debbie Docherty of the Bonneville Power Administration for administrative support and guidance, and Julie Burke and Celeste Reves of the CTUIR for administrative and logistical support. This study was funded by the Bonneville Power Administration.
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Torgersen, C.E., D.M. Price, H.W. Li, and B.A. McIntosh. 1999. Multiscale thermal refugia and stream habitat associations of chinook salmon in northeastern Oregon. Ecological Applications 9: 301-319.
Torgersen, C.E., C.V. Baxter, H.W. Li., and B.A. McIntosh. In press. Landscape influences on longitudinal patterns of river fishes: Spatially continuous analysis of fish-habitat relationships. Pages xxx-xxx in R. M. Hughes, L. Wang, and P. W. Seelbach, editors. Influences of landscapes on stream habitats and biological assemblages. American Fisheries Society, Symposium xx, Bethesda, Maryland.
Vannote, R. L., G. W. Minshall, K. W. Cummins, J. R. Sedell and C. E. Cushing. 1980. The river continuum concept. Canadian Journal of Fisheries and Aquatic Sciences 37:130-137.
Vannote, R. L., and G. W. Minshall. 1982. Fluvial processes and local lithology controlling abundance, structure, and composition of mussel beds. Proceedings of the National Academy of Science 79: 4103-4107.
Vaughn, C.C., 1997. Regional patterns of mussel species distributions in North American rivers. Ecography 20(2), 107-115.
33
Williams, J. D., M. Warren, K. Cummings, J. Harris, and R. Neves. 1993. Conservation status of freshwater mussels of the United States and Canada. Fisheries 18(9):6-22.
34 Table 1. The total number of sites surveyed in each river drainage.
Umatilla Umatilla MF John Day NF John Day mainstem tributaries Mainstem mainstem Number of sites 31 24 26 13 Sites w/ Anodonta 2 2 22 6 Sites w/ Gonidea 2 0 15 2 Sites w/ Margaritifera 0 0 20 11 Sites with all species 0 0 12 2
35
Table 2. Number of mussels found in each river drainage.
Umatilla Umatilla MF John Day NF John Day main stem tributaries main stem main stem No sites sampled 31 24 25 14 Number of Anodonta 61 10 4396 375 Number of Gonidea 4 0 5623 21 Number of Margaritifera 0 0 1982 4921 Total Mussels Counted 65 10 12001 5317
36 Table 3. Characteristics of different types of stream reaches (modified from Montgomery and Buffington 1993).
Cascade Step-pool Plane-bed Pool-Riffle Regime Braided
Bed material Boulder Cobble/boulder Gravel/cobble Gravel Sand Variable
Dominant Boulders, Bedforms (steps, Boulders and Bedforms (bars, Sinuosity, bedforms Bedforms (bars, roughness banks pools) boulder, cobbles, pools), boulders (dunes, ripples, pools) elements large woody banks and cobbles, large bars), banks debris, banks woody debris, sinuosity, banks
Dominant Fluvial, Fluvial, hillslope, Fluvial, bank Fluvial, bank Fluvial, bank Fluvial, bank sediment sources hillslope, debris flows erosion, erosion, inactive erosion, inactive erosion, debris debris debris flows channels, debris channels flows flows flows
Typical slope (%) 8-30 4-8 1-4 0.1-2 <0.1 <3
Pool spacing <1 1-4 None 5-7 5-7 Variable (channel widths)
37 Table 4. Description of study reaches. Modified from McDowell 2001.
Reach Reach length Channel Drainage area Land ownership; and Major human channel surveyed (m) units (#) in per reach recent use modifications reach (km2)
A 595 8 1090 Private land; limited Road encroachment grazing
B 930 15 890 Private land; limited Road encroachment grazing
C 760 14 850 Mixed: national forest Placer mining, straight channel private, grazing, residential
D 1030 14 810 Mixed national forest None and private; grazing
E 4415 64 630 Private lands; grazing, Channel straightening, rip-rap nature preserve
F 3575 68 560 National forest; limited None grazing
38 Table 5. Characteristics of each survey reach. Length and width data were calculated from direct measurements; mean gradient, range and valley width was generated through a numberical program developed by Earth Systems Institute (Miller 2002, 2003) using 10-meter digital elevation models.
Reach Length Mean Mean Gradient Valley surveyed (m) width (m) gradient (%) range width (m)
A 596 13.2 0.6 0.4 – 0.8 100
B 931 11.9 1.0 0.03 - 2.8 113
C 754 9.5 0.3 0.1 - 0.5 146
D 969 12.1 0.8 0.02 - 2.2 256
E 4814 12.4 0.7 0.4 – 1.0 192
F 3575 12.9 0.6 0.5 - 0.8 121
39 Table 6. Reach lengths and changes in sinuosity between 1939 and 1990 in the Middle Fork John Day River.
Channel Length (m) Valley Sinuosity Change in 1939 1990 width (m) 1939 1990 sinuosity (%)
Reach D 4,195 3,682 2,760 1.52 1.33 13
Reach E 11,820 8,946 7,542 1.57 1.19 25
Reach F 2,665 2,711 2,507 1.06 1.08 2
40 Table 7. Number of each species found in each geomorphic channel type (cascade, riffle, run or pool).
Channel unit Channel Total length of Channel Margaritifera (#) Anodonta (#) Gonidea (#) type units (#) unit type (m) type (%)
Cascade 14 641 6 51 or .08 / m 2 or .003 / m 0
Riffle 80 5,893 51 860 or 0.15 / m 220 or 0.04 / m 23 or 0.003 / m
Run 78 4,458 39 1803 or 0.4 / m 1170 or 0.26 / m 93 or 0.02 / m
Pool 7 401 4 411 or 1.03 / m 544 or 1.36 / m 86 or 0.21 / m
41
Table 8. Categorical used to characterize the surface sediments associated with mussel occurrence. Definitions of the five sediment classes are presented in the table.
Surface Sediment Class Values Definition
Mean Particle Size large, medium, small Average size of sediment particles
Sorting well, poor Spread of sediment sizes
Proportion Sand Present high, medium, low Relative amount of sand present
Proportion Fines Present high, low Relative amount of clay, silt present
Vegetation Present yes, no Milfoil or sedge mats present
42
Table 9. The number of quadrats sampled in each reach and the number of mussels found in each quadrat.
Quadrats Quadrats w/ Quadrats w/ Quadrats w/ Reach Unit (#) Anodonta Margaritifera Gonidea Anodonta Margaritifera Gonidea A Run 20 34 5 2 15 5 2 A Run 19 35 13 2 15 7 2 A Run 20 7 34 50 7 13 15 A Run 19 3 2 4 3 2 3 A Run 14 31 5 4 10 4 2
B Run 20 32 37 24 15 11 8 B Run 11 10 9 4 5 5 4 B Run 15 25 5 4 7 4 4 B Run 20 75 7 4 13 5 2 B Run 20 51 12 3 15 7 2
F Pool 20 19 55 0 8 12 0 F Pool 16 9 70 0 6 12 0 Totals 214 331 254 101 119 87 44
43 Table 10. The niche breadth and the number of resources states used by the three species in each reach.
Smith's Number of Measure Resource Species Reach Unit (niche breadth) States Used Anodonta A Run 0.971 12 Anodonta A Run 1 8 Anodonta A Run 0.944 8 Anodonta B Pool 0.981 8 Anodonta B Run 0.901 17 Anodonta F Pool 0.957 6
Margaritifera A Run 0.974 8 Margaritifera A Run 0.977 8 Margaritifera A Run 0.987 2 Margaritifera B Pool 0.967 9 Margaritifera B Run 0.987 7 Margaritifera F Pool 0.971 11
Gonidea A Run 1 3 Gonidea A Run 0.968 10 Gonidea A Run 0.966 2 Gonidea B Pool 0.945 8 Gonidea B Run 0.973 3
44
Table 11. The resource states and characteristics of the microscale utilized by the three species.
Resource State Resource (%) Particle Size Sorting Sand (%) Fines (%) Vegetation Anodonta (%) Margaritifera (%) Gonidea (%)
25 3.13 Medium Well Low Low Yes 10.92 2.16 13.04
20 10.4 Medium Poor Medium Low No 6.83 19.91 16.3
16 25.5 Medium Poor Low Low No 12.63 18.18 5.43
9 10.9 Large Well Low Low No 7.51 10.39 19.6
45 Table 12. Mean lengths of mussel species in the three reaches. Asterik represent significant differences between reaches.
Reach A Reach B Reach F
Anodonta 42.4 37.1* 47.0
Margaritifera 58.2* 41.5* 78.1*
Gonidea 58.2* 41.5*
46 Table 13. Preferences for particular habitats or habitat types at all three spatial scales measured for Anodonta, Margaritifera and Gonidea.
SCALE MACRO MESO MICRO
Longitudinal Channel Unit Preferred Channel Niche Breadth Niche Overlap Variation Gradient
Anodonta spp. More Most common in Most common in Habitat generalist Most common in 4 common in pools and runs; rare areas with slope < resource states that mid to lower in riffles and 1%. overlapped with reaches. cascades. other two genera (Table 9).
Margaritifera More Most common in Occur in channel Habitat generalist Most common in 4 common in pools, but found in all areas up to a slope resource states that upper reaches. channel unit types, of 3%. overlapped with other two including cascades. genera (Table 9).
Gonidea More Most common in most common in Habitat generalist Most common in 4 common in pools, rare in runs areas with slope < resource states that lower reaches. and riffles, absent 1%. overlapped with other two from cascades. genera (Table 9).
47 Figure 1. Map of the Middle Fork John Day River watershed and the 35-km study area.
48 Figure 2. Mean monthly discharge (cm / s) in the Middle Fork John Day River. Mean monthly discharge was calculated from measurements taken at the Ritter gauging station from 1920 – 2003.
Middle Fork John Day
25
20
15
10
5
Mean monthly flow - 1929-2002 (cms) 1929-2002 - flow monthly Mean 0 JFMAMJJASOND
49 Figure 3. The relative abundance and density (# / m) of mussels by genus in each reach (A and B), and the abundance and density (# / m) for all species combined (C and D). The blue diamonds represent the number of Margaritifera found in each reach; pink squares represent Anodonta; and the green triangles, Gonidea.
1.0 1600 A) B) 0.8 1200 0.6 800 0.4 400
0.2 reach / mussels # # mussels meter / 0.0 0 ABCDEF ABCDEF Sample Reaches Sample Reaches Upstream Upstream Margaritifera Anodonta Gonidea Margaritifera Anodonta Gonidea
C) All mussels D) All mussels
1.5 1500
1.0 1000
0.5 500 # mussels / meter / # mussels 0.0 reach / # mussels 0 ABCDEF ABCDEF Sample Reaches Sample Reaches Upstream Upstream All mussels All mussels
50 Figure 4. Density of mussel species found in the study reaches. Note that Margaritifera have greater densities in the upper reaches while Anodonta and Gonidea are more dominant in the downstream reaches.
51 Figure 5. The percentage of each species found in the six reaches. Green represents Margaritifera falcata, red represents Anodonta spp. and blue Gonidea angulata.
Reach A Reach B Reach C
2% 16% 7% 25% 23% 16%
59% 70% 82% M. falcata Anodonta sp. Reach D Reach E Reach F G. angulata
9% 7% 41% 59% 91% 93%
52 Figure 6. The longitudinal profile of the MFJD River and the location of the study reaches included in this study. Bottom panel is a close-up of study reaches.
1800 1600 1400 F D B A 1200 1000 C 800 600 Elevation (m) Elevation 400 200 0 125 100 75 50 25 0 Distance from mouth (km) 1150 F E 1100 D C 1050 B 1000
A (m) Elevation 950
900 85 75 65 55 45 Distance from mouth (km)
53 Figure 7. The elevation change of the MFJD River (dark red line) and the gradient along the course of the river (blue line). The brigh red line shows the location of the study reaches surveyed. Note the highly variable gradient in the study area.
10 2000 9 8 Elevation 1600 7 6 1200 5 4 Gradient 800
3 (m) Elevation
Mean gradient (%) gradient Mean 2 400 1 0 0 0 50 100 Distance from mouth (m)
54 Figure 8. The number of mussels, per meter (top panel), and total (middle panel) found in the four channel types. Note that riffles and runs occurred in roughly the same percentages (bottom panel) but were the least utilized mesoscale habitat types. 2.0
Gonidea 1.5 Anodonta Margaritifera
1.0
Mussel / meter 0.5
0.0 Cascade Riffle Run Pool 3200 2800
2400 2000
1600
1200 Total mussels 800
400 0 Cascade Riffle Run Pool 50
40
30
20
Percent of channel of Percent 10
0 Cascade Riffle Run Pool
55 Figure 9. The number of mussels found per channel unit (red bars) in reach A and the corresponding gradient along the channel (blue line). The bright red line represents the mean gradient in reach A. In this reach the greatest number of mussels occur in the lowest gradient units.
Reach A
350 0.035
300 0.03
250 0.025
200 Mean gradient 0.02
150 0.015 Gradient
channel unit 100 0.01 Mussels found / 50 0.005
0 0 0 115 200 439 596 Distance downstream (m)
Mussels / channel unit Gradient
56 Figure 10. The number of mussels found per channel unit (red bars) in reach B and the corresponding gradient along the channel (blue line). The bright red line represents the mean gradient in reach B. In general, the greatest number of mussels occurred in geomorphic units with the lowest average channel gradient.
Reach B
400 0.03 350 Mean gradient 0.025 300 0.02 250 200 0.015
150 Gradient 0.01 channel unit
Mussels found / 100 0.005 50 0 0 0 63 192 378 638 787 842 882 Distance downstream (m)
Mussels / channel unit Gradient
57 Figure 11. The number of mussels found per channel unit (red bars) in reach C and the corresponding gradient along the channel (blue line). The bright red line represents the mean gradient in reach C. In this reach, low channel gradient does not correspond to a high abundance of mussels. Compared to the other reaches, few mussels were found in reach C in general.
Reach C
140 0.04
120 0.035 0.03 100 0.025 80 Mean gradient 0.02 60
0.015 Gradient
channel unit 40
Mussels found / 0.01 20 0.005 0 0 0 101 164 271 436 584 674 754 Distance downstream (m)
Mussels / channel unit Gradient
58 Figure 12. The number of mussels found per channel unit (red bars) in reach D and the corresponding gradient along the channel (blue line). The bright red line represents the mean gradient in reach D. As in reach C, the areas of channel with the lowest channel gradient do not contain the greatest abundance of mussels.
Reach D
70 0.025
60 Mean gradient 0.02 50
40 0.015
30 0.01 Gradient
channel unit 20 Mussels found / 0.005 10
0 0 0 268 386 520 668 708 921 Distance downstream (m)
Mussels / channel unit Gradient
59 Figure 13. The number of mussels found per channel unit (red bars) in reach E and the corresponding gradient along the channel (blue line). The bright red line represents the mean gradient in reach E. In general, the greatest number of mussels occurred in the areas of channel in this reach with the lowest average channel gradient.
Reach E
Mean gradient in reach 140 0.03
120 0.025 100 0.02 80 0.015 60
0.01 Gradient channel unit 40 Mussels found / 20 0.005
0 0 0 758 1620 2277 3057 3607 4318 Distance downstream (m)
Mussels / channel unit Gradient
60 Figure 14. The number of mussels found per channel unit (red bars) in reach F and the corresponding gradient along the channel (blue line). The bright red line represents the mean gradient in reach F.
Reach F
140 0.025 Mean gradient 120 0.02 100
80 0.015
60 0.01
Gradient channel unit 40 Mussels found / 0.005 20
0 0 955 1534 2270 2993
Distance downstream (m)
Mussels / channel unit Gradient
61 Figure 15. The top panel shows bed surface elevation (dark blue line) and water surface elevation (pink line) moving downstream in reach A. The dashed blue line illustrates the number of Margaritifera falcata found within the study reach; the green dashed line represents Anodonta spp., and the red, Gonidea angulata. The bottom panel categorizes the reach in terms of geomorphic units (C = cascades, RF = riffles, R = runs, and P = pools). The bars represent the number of mussels found per channel unit within the reach (blue = Margaritifera falcata; green = Anodonta spp.; and red = Gonidea angulata)
Reach A
946.0 140 Bed Elevation (m)
Water Surface 120 945.0 Elevation (m) Margaritifera 100 Anodonta 944.0 80 Gonidea 943.0 60 Mussels (#) Mussels Elevation (m) Elevation 40 942.0 20
941.0 0 0 100 200 300 400 500 600 Distance downstream (m)
400 70
P 60
300 50
40 200
30
P R RF R 20 Mussels (#/ unit) 100
RF RF RF 10
0 0 0 115 200 439 596 Distance downstream (m)
M. falcata Anodonta G. angulata
62 Figure 16. The top panel shows bed elevation and water surface elevation moving downstream in reach B. The dashed blue line illustrates the number of Margaritifera falcata found within the study reach; the green dashed line represents Anodonta spp., and the red, Gonidea angulata. The bottom panel categorizes the reach in terms of geomorphic units (C = cascades, RF = riffles, R = runs, and P = pools). The bars represent the number of mussels found per channel unit within the reach (blue = Margaritifera falcata; green = Anodonta spp.; and red = Gonidea angulata)
Reach B
1012 350 Bed Elevation (m) 1011 Water Surface 300 Elevation (m) Margaritifera 250 1010 Anodonta 200 1009 Gonidea 150 Mussels (#) Mussels
Elevation (m) Elevation 1008 100
1007 50
1006 0 0 200 400 600 800 1000 Distance downstream (m)
400 140 P R 120
300 100
80 R 200 R
60 R
40
Mussels (# / unit) 100 RF R RF R RF R 20 RF RF R RF 0 0 0 63 192 378 638 787 842 882 Distance downstream (m)
M. falcata Anodonta G. angulata
63 Figure 17. The top panel shows bed elevation and water surface elevation moving downstream in reach C. The dashed blue line illustrates the number of Margaritifera falcata found within the study reach; the green dashed line represents Anodonta spp., and the red, Gonidea angulata. The bottom panel categorizes the reach in terms of geomorphic units (C = cascades, RF = riffles, R = runs, and P = pools). The bars represent the number of mussels found per channel unit within the reach (blue = Margaritifera falcata; green = Anodonta spp.; and red = Gonidea angulata)
Reach C
1036 140
120 1035 100
80 1034 60 Mussels (#) Mussels Elevation (m) Elevation 40 1033 20
1032 0 0 100 200 300 400 500 600 Distance downstream (m)
Bed Elevation (m) Water Surface Elevation (m) Margaritifera Anodonta Gonidea
150 25.00
125 20.00 P 100
15.00 75 R R
10.00 50 R Mussels (# / unit) RF RF P RF R 5.00 25 RF P R RF RF 0 0.00 0 101 164 271 436 584 674 754 Distance downstream (m)
M. falc ata Anodonta G. angulata
64
Figure 18. The top panel shows bed elevation and water surface elevation moving downstream in reach D. The dashed blue line illustrates the number of Margaritifera falcata found within the study reach; the green dashed line represents Anodonta spp., and the red, Gonidea angulata. The bottom panel categorizes the reach in terms of geomorphic units (C = cascades, RF = riffles, R = runs, and P = pools). The bars represent the number of mussels found per channel unit within the reach (blue = Margaritifera falcata; green = Anodonta spp.; and red = Gonidea angulata)
Reach D
1056 50 Bed Elevation (m) 1055 Water Surface Elevation (m) 40 1054 Margaritifera Anodonta 1053 30
1052 20 Mussels (#) Elevation (m) Elevation 1051 10 1050
1049 0 0 200 400 600 800 1000 Distance downstream (m)
70 40
R 35 60
30 50 R
25 40 R P 20 30
15 20 RF Mussels (# / unit) R R 10 R
10 RF 5 R RF RF C RF 0 0 0 268 386 520 668 708 921 Distance downstream (m)
M. falc ata Anodonta
65 Figure 19A. The top panel shows bed elevation and water surface elevation moving downstream in the upper most portion of reach E. The dashed blue line illustrates the number of Margaritifera falcata found within the study reach; the green dashed line represents Anodonta spp., and the red, Gonidea angulata. The bottom panel categorizes the reach in terms of geomorphic units (C = cascades, RF = riffles, R = runs, and P = pools). The bars represent the number of mussels found per channel unit within the reach (blue = Margaritifera falcata; green = Anodonta spp.; and red = Gonidea angulata)
Reach E
1105 Bed Elevation (m) 120 Water Surface Elevation 1100 (m) 100 Margaritifera 1095 Anodonta 80 1090 60 1085 Mussels (#) Mussels
Elevation (m) Elevation 40 1080
1075 20
1070 0 0 500 1000 1500 2000 2500 Distance downstream (m)
120 120 RF 100 100
80 80 R R
60 R P 60 R
40 R 40 R Mussels (# / unit) R RF R 20 20 RF RF RF RF RF R R R RFC RF RF R PRFRF RF RF RF 0 RF R 0 0 467 758 1204 1620 2031 2277 Distance downstream (m)
M. falcata Anodonta
66 Figure 19B. The top panel shows bed elevation and water surface elevation moving downstream in the most downstream portion of reach E. The dashed blue line illustrates the number of Margaritifera falcata found within the study reach; the green dashed line represents Anodonta spp., and the red, Gonidea angulata. The bottom panel categorizes the reach in terms of geomorphic units (C = cascades, RF = riffles, R = runs, and P = pools). The bars represent the number of mussels found per channel unit within the reach (blue = Margaritifera falcata; green = Anodonta spp.; and red = Gonidea angulata)
Reach E
1105 120 Bed Elevation (m) 1100 Water Surface 100 Elevation (m) 1095 Margaritifera 80 Anodonta 1090 60 1085 Mussels (#)
Elevation (m) Elevation 40 1080
1075 20
1070 0 2500 3000 3500 4000 4500 Distance downstream (m)
160 140 RF
140 120 120 100 R RF R 100
80 80
60 P R R 60 P R RF RF 40 Mussels (# / unit) 40 R
RRF 20 R R 20 R R RF C RF RF RF RF R RF RF RC RF 0 0 2563 2784 3260 3504 3894 4165 4488 Distance downstream (m)
M. falcata Anodonta
67 Figure 20A. The top panel shows bed elevation and water surface elevation moving downstream in the upper most portion of reach F. The dashed blue line illustrates the number of Margaritifera falcata found within the study reach; the green dashed line represents Anodonta spp., and the red, Gonidea angulata. The bottom panel categorizes the reach in terms of geomorphic units (C = cascades, RF = riffles, R = runs, and P = pools). The bars represent the number of mussels found per channel unit within the reach (blue = Margaritifera falcata; green = Anodonta spp.; and red = Gonidea angulata)
Reach F
1115 150
1110 120
Bed Elevation (m)
1105 Water Surface Elevation 90 (m) Margaritifera
1100 Anodonta 60 Mussels (#) Elevation (m) Elevation
1095 30
1090 0 0 500 1000 1500 Distance downstream (m)
60 60 R R 50 50
40 R 40 R 30 30 R 20 20 R Mussels (#unit) /
10 RF 10 RF RF C C RF R RF R RF C R RF C RF 0 0 RF 0 459 997 1188 1620 Distance downstream (m)
M. falcata Anodonta
68 Figure 20B. The top panel shows bed elevation and water surface elevation moving downstream in the most downstream portion of reach F. The dashed blue line illustrates the number of Margaritifera falcata found within the study reach; the green dashed line represents Anodonta spp., and the red, Gonidea angulata. The bottom panel categorizes the reach in terms of geomorphic units (C = cascades, RF = riffles, R = runs, and P = pools). The bars represent the number of mussels found per channel unit within the reach (blue = Margaritifera falcata; green = Anodonta spp.; and red = Gonidea angulata)
Reach F
1115 150 Bed Elevation (m)
1110 Water Surface 120 Elevation (m) Margaritifera
1105 Anodonta 90
1100 60 Mussels (#) Mussels Elevation (m) Elevation
1095 30
1090 0 1900 2100 2300 2500 2700 2900 3100 3300 3500 Distance downstream (m)
300 250
P 250 200
200 R 150
150 RF R
100
100 RF R P Mussels (# / unit) / (# Mussels
RF 50 50 RF R R R R RF RF R RF RF RF R RF R 0 R 0 1901 2321 2758 3035 3476 Distance downstream (m)
M. falcata Anodonta
69 Figure 21. The relationship between mussels (by species) and slope (%) for all reaches surveyed. Mussels were more common in areas of low gradient. Margaritifera occurred in higher slope areas than the other two genera. However, there appeared to be an upper gradient threshold (~ 3%) above which mussels did not occur.
Margaritifera 6
5 4
3 2
Anodonta / meter / Anodonta 1 0 0 0.01 0.02 0.03 0.04 0.05 0.06 Slope
Anodonta 4
3
2
1 Anodonta / meter
0 0 0.01 0.02 0.03 0.04 0.05 0.06 Slope
Gonidea 0.80
0.60
0.40
0.20 Gonidea / meter
0.00 0 0.01 0.02 0.03 0.04 0.05 0.06 Slope
A B C D E F
70 Figure 22. Histogram of the slopes per geomorphic channel type. Geomorphic channel units were closely correlated with gradient, in that slope was greatest in cascade reaches (ranging from 1.5 to 7 % gradient), lowest in pools (ranging from 0 – 1% slope) (Figure 22), and ranged from 0 to 7% in riffles, and 0 to 2% in runs.
30 Cascade 20
10
0 01234567 30 Slope (%) Riffle 20
10
0 01234567 30 Slope (%) Run 20
Number of reaches Number 10
0 01234567 30 Slope (%) Pool 20
10
0 01234567 Slope (%) 71 Figure 23. The percentage of habitat available and utilized by the three species per channel unit type. Note that both run and pool habitat were utilized at a greater rate by all species.
All Reaches
75
50
25
0 Cascade Riffle Run Pool
Habitat Available Margaritifera Anodonta Gonidea
72 Figure 24. The distribution of mussels among channel types per reach based on the Strauss linear selection index. The index ranges from –1.00, indicating a habitat is abundant but completely avoided by a particular species, to +1.00, indicating a habitat that is rare is used exclusively by a species. A value of 0 indicates that the habitat is used in about the same proportion as its abundance. Note a general positive association with pools and a negative association with riffles and cascades.
Margaritifera Anodonta Gonidea Reach D Reach A 0.60 0.60
0.30 0.30 0.00 0.00
-0.30 -0.30
-0.60 -0.60 Riffle Run Pool Cascade Riffle Run Pool
Reach E 0.60 Reach B 0.60
0.30 0.30
0.00 0.00
-0.30 -0.30
-0.60 -0.60 Riffle Run Pool Cascade Riffle Run Pool
Reach C Reach F 0.60 0.6
0.30 0.3
0.00 0
-0.30 -0.3
-0.60 -0.6
Riffle Run Pool Cascade Riffle Run Pool
73
CHAPTER TWO
HISTORICAL DISTRIBUTION OF FRESHWATER MUSSELS IN THE UMATILLA AND JOHN DAY RIVER SYSTEMS.
Tribal Fisheries Program Department of Natural Resources Confederated Tribes of the Umatilla Indian Reservation Pendleton, Oregon, U.S.A.
74 INTRODUCTION
An understanding of where freshwater mussels historically occurred in the mid-Columbia Basin can provide a context for interpreting their current distribution as well as the factors that led to local extirpations or colonizations. Long-term changes in the historical distribution of animal species can be obtained through geologic and archeological records. More recent data can be obtained from oral interviews, published and unpublished (e.g., field notes) sources, and museum records or archived specimens. Freshwater mussels were historically an important food for mid-Columbia tribal peoples. Middens of freshwater mussel shells are not uncommon at historical village sites and this archeological record of harvest dates back over 10,000 years (Lyman 1984). William Clark, on October 18, 1805, noted in his journal that “here I observed banks of Muscle Shells banked up in the river in several places,” in the Columbia River just upstream of the mouth of the Umatilla River (personal communication, Teara Farrow, Cultural Resources Protection Program, CTUIR). The close proximity of shell middens to village sites suggests that villages may have been placed strategically close to large mussel beds (Hunn 1990). Freshwater mussels were harvested during salmon fishing or when river conditions were favorable. In addition, mussels may have been harvested during periods when other foods sources were limited, such as late winter (Hunn 1990). Historically many Native American tribes used marine and/or freshwater shells for money (e.g., wampum) and adornment (e.g., scarves, capes and belts). The use of marine shells in Native American cultures along the northwestern coast of the United States has been well documented (Hunn 1990). Less is known about the historical uses of freshwater shells by inland tribes, including the Umatilla, Walla Walla and Cayuse peoples, although ornament shells have been found at burial sites in the lower Umatilla River (Osborne 1951). The use of freshwater mussels by tribal peoples has declined in recent decades due to changes in subsistence needs. In addition, the loss of suitable habitat for freshwater mussels in the main stem of the Columbia River and its tributaries, including the Umatilla, has severely limited the accessibility of this resource to tribal peoples.
75 The objective of this study was to ascertain where mussels historically occurred in the Umatilla and John Day River systems. An understanding of where mussels historically occurred in a river basin can potentially aid in conservation and recovery efforts, and will aid in future efforts to restore mussel populations in the Umatilla River Basin. This historical information will be used to establish a context for the interpretation of survey data collected in 2003 and 2004, and can serve as a baseline for analyzing changes in freshwater mussel distribution in the John Day and Umatilla River systems. This study is a continuation of the historical data collected for this project included in Brim Box et al. (2003).
METHODS
Literature Review Information on the historical occurrence of freshwater mussels in mid-Columbia drainages, especially the Umatilla and John Day River systems, was obtained from several sources. A thorough historical literature search was conducted to obtain published and unpublished records of freshwater mussels from the Umatilla, John Day, and other mid- Columbia River drainages through the USDA Forest Service Freshwater Mollusk Database at Utah State University. This database contains records of historical occurrences of bivalves in the western United States, dating back to the 1830s.
Personal Accounts Tribal members were contacted to ascertain how people in the Umatilla Basin utilized mussels and where historical middens, burial sites or villages once occurred in the drainage (and hence, where historically mussels might have been harvested). Staff members of the Cultural Resources Protection Program (CRPP) of the CTUIR were also asked if they had reports, archival material, or oral histories about freshwater mussels in the Umatilla Basin. Historical documents regarding archeological sites in the Columbia Basin were also reviewed.
Museum Collections Bivalve collections at the Academy of Natural Sciences, Philadelphia (ANSP), were physically inventoried for freshwater mussel shells and unpublished notes of mussel occurrences
76 and/or anecdotal information in western US drainages. Digital photo documentation of most of the mussels housed in the ANSP from the western United States was obtained for future reference. The museum data obtained from the ANSP was added to museum data collected during 2003 from the California Academy of Sciences (CAS) in San Francisco and at the United States National Museum (USNM) in Washington, D.C.
RESULTS
Literature Review Published accounts of freshwater mussels collected from Oregon drainages date to the 1830s. Of these records, only two do not list a specific drainage. Accounts from the Columbia River drainage comprise about a third of these records. Columbia Basin records include seven of the eight species known to currently occur in the western United States: Anodonta berigiana, Anodonta californiensis, Anodonta kennerlyi, Anodonta nuttaliana, Anodonta oregonensis, Gonidea angulata and Margartifera falcata. No records were found from the Umatilla or Middle Fork John Day rivers, although records include nearby drainages (e.g., the Walla Walla).
Personal Accounts Eleven of the seventeen Tribal members contacted recalled seeing mussels in the Umatilla River (Table 1). Four members remembered when mussels disappeared in the river. Tribal members remembered gathering mollusks at the mouth of the Umatilla and Walla Walla rivers and at the mouth of Squaw Creek. One tribal member commented, "at one time mussels were plentiful in all tributaries and bigger mussels were found in the main stem of the Umatilla River" (personal communication, Armand Minthorn, CTUIR tribal member, 2003). In the mid- 1940s, freshwater mussel shells were observed scattered along the upper reaches of the banks of the Umatilla River (personal communication, Bernadette Nez, CTUIR tribal member, 2003).
77 Table 1. Responses of Tribal members who were asked about freshwater mussels in the Umatilla River Basin.
Responses #
Tribal members contacted 17
Remembered seeing freshwater mussels in Umatilla Basin 11
No recollection of seeing freshwater mussels in Umatilla Basin 5
No recollection of seeing in Umatilla, but recalled seeing in other rivers 1
Reported mussels disappeared after Umatilla was treated with rotenone 3
Reported mussels disappeared after bridge construction 1
Reported mussels disappeared after road construction 1
Staff members of the CRPP reported they knew of no archival material (e.g., reports, oral histories, shell ornaments) regarding freshwater mussels in the Umatilla River upstream of its confluence with the Columbia River. However, they did report that Tribal archaeological sites (e.g., shell middens and burial sites) were known from the confluence of the Umatilla River and other areas of the Columbia River drainage.
Museum Collections Over 175 records of freshwater mussel occurrences from Oregon were found in the museum collections examined (Appendix 1a). An additional 108 records were found in the USDA Forest Service western mollusk database (Table 2 and Appendix 1b). Some of these latter records refer to the same specimens recorded in natural history museum searches. For example, mussel shells collected by Thomas Nuttall during the Rocky Mountain Boundary Survey are now housed in the ANSP and USNM. Some of Nuttall’s material was described by Isaac Lea as new species (e.g., Anodonta nuttalliana), and those publication records are included in the USFS database. Therefore museum records and database records are not mutually exclusive.
78 Table 2. Number of records of freshwater mussel occurrences found during museum and database searches.
Source of Museum and or Database Records Records (#) from Oregon Rivers USDA Forest Service Freshwater Mollusk Database 108 Academy of Natural Sciences, Philadelphia (ANSP) 51 United States National Museum (USNM) 84 California Academy of Sciences (CAS) 43 Total 286
Over 170 historical records (i.e., shell material in museum collections) of freshwater mussels from the western United States were found at the ANSP. Combined with records collected in 2003 from the USNM and CAS, about 800 museum records were obtained for this study. Of these records, 178 are from Oregon. Many of the Oregon records (similarly to what was found in the historical publications search) are from the Columbia River Drainage. Although all eight species known from the western United States were present in museum collections, none was from the two rivers targeted in this study.
DISCUSSION
Scant historical information was found on freshwater mussel occurrences in both the John Day or Umatilla River systems. Based on recent surveys of these drainages (e.g., Brim Box et al. 2003) it is known that all three genera of freshwater mussels known to the western United States occur in the Middle Fork John Day River, but are absent or uncommon in the Umatilla River. It is unusual to find a lack of archival material for river systems, like the Middle Fork John Day, that contain widespread, diverse and abundant mussel populations. The lack of historical records from these two systems suggests that archival data for these two systems (e.g., museum records, published accounts) do not provide a context for the interpretation of the survey data collected for this study in 2003 and 2004. No records of freshwater mussel occurrences were found in this study for the Umatilla River, but three records of gastropods (i.e., snails) were found in the ANSP. Based on the tags accompanying these records, the collection of this shell material was probably made during the
79 late 1800s or early 1900s. Although these records prove that conchologists visited the Umatilla River, it does not shed additional light on whether freshwater mussels historically occurred in the system. Although Margaritifera falcata was not found in the Umatilla River during recent surveys, multiple shells of this species were found about 115 kilometers upstream of the confluence with the Columbia River. These shells were unearthed during the construction of the Emaceus holding facility. These shells may indicate that a bed of M. falcata historically occurred at this site, in an old river channel that is now dewatered. Alternatively, it is possible that these shells were part of a previously unknown midden. Shell middens have been found at village sites near the mouth of the Umatilla River (Lyman 1984) and mussel shells were present at burial sites in the same area (Osborne 1951). The presence of M. falcata shells at this site should be further investigated. In addition, a zooarcheologist may be able to identify other sites on the Umatilla River that could potentially harbor mussel shells. The majority of tribal members who were asked about the occurrence of freshwater mussels in the Umatilla River system recalled seeing mussels in the system. However, it is apparent that the use of freshwater mussels for consumption or other uses is no longer a common practice. A Umatilla tribal elder, contacted prior to this study, remembered his parents trading fish for dried mussels as late as the 1930s (personal communication, Eli Quaempts, CTUIR tribal member, 1996). In his book Nch’I-Wana, “The Big River”, Hunn (1990) reported that tribal elders of the Umatilla, Nez Perce and Cayuse tribes recalled eating Margaritifera falcata. Consistent with the results of this study, Hunn (1990) also wrote that, “No one to my knowledge bothers with them today and the knowledge of where to find them and how to harvest and prepare them is being lost” (Hunn 1990). The limited amount of information obtained from Tribal members regarding the historical distribution of freshwater mussels in the Umatilla River system corroborates this statement. The lack of historical data on the distribution of freshwater mussels in the Umatilla River system limits our ability to interpret their current distribution in the basin, as well as causal agents of extirpation. For example, although there is anecdotal information freshwater mussels once occurred in several reaches of the Umatilla River, it was not possible to discern which genera occurred in which reaches. A more thorough examination of sites on or near the Umatilla
80 River where shell material was found, as well as the shells themselves, could augment the interpretation of data collected in this study.
ACKNOWLEDGEMENTS
We thank Debbie Docherty of the Bonneville Power Administration for administrative support and guidance, and Julie Burke and Celeste Reves of the CTUIR for administrative and logistical support. This study was funded by the Bonneville Power Administration.
81 LITERATURE CITED
Brim-Box, J., D. Wolf, J. Howard, C. O'Brien, D. Nez, D. Close. 2003. Distribution and Status of Freshwater Mussels in the Umatilla River System, 2002-2003 Annual Report, Project No. 200203700, 74 electronic pages.
Hunn, E. S. 1990. Nch’i-Wana “The Big River” Mid-Columbia Indians and Their Land. University of Washington Press, Seattle, Washington.
Lyman, R.L. 1984. A model of large freshwater clam exploitation in the prehistoric southern Columbia Plateau culture area. Northwest Anthropological Research Notes 18:97-107.
Osborne, H. D. 1951. Excavations near Umatilla, Oregon: The archaeology of the Columbia Intermontane Province. Ph.D. dissertation, University of California, Berkeley, California.
82 Appendix 1a. Freshwater mussel occurrences from Oregon found in the museum collections.
Catalog # Original ID Location (as written on original museum tag) ANSP 123894 (M. falcata) Chehalis River, W.T. ANSP 41030 A. anglulata Lewis River, Oregon ANSP 41035 A. anglulata Yakima River, Wash. Terr. ANSP 126509 Anodonta Humboldt River, Bank's Junction House, N.T. ANSP 76182 Anodonta Warner's 2nd & 3rd Lakes USNM 7073 Anodonta South Umpqua River USNM 431093 Anodonta Blitzen Valley USNM 652824 Anodonta Klamath Co ANSP 41029 Anodonta angulata Falls Willamette River ANSP 71705 Anodonta angulata near Portland ANSP 323956 Anodonta angulata Umpqua River ANSP 323944 Anodonta angulata Umpqua River ANSP 365646 Anodonta angulata Washington Territory (= Oregon and Washington) USNM 40665 Anodonta angulata Oregon USNM 86758 Anodonta angulata Walla Walla, Oregon USNM 86756 Anodonta angulata Walla Walla, Oregon USNM 652855 Anodonta californiensis Powder River USNM152644 Anodonta californiensis Elk Creek USNM 652856 Anodonta californiensis Powder River ANSP 129922 Anodonta cognata Fort George ANSP 150641 Anodonta cygnea Columbia Slough USNM 7075 Anodonta feminalis Walla Walla, Oregon USNM 99321 Anodonta fluviatilis Portland USNM 104164 Anodonta kennerley near Portland ANSP 111342 Anodonta kennerlyi Canal from Tualatin River to Oswego Lake, Clackamas Co., Oregon
ANSP 11264 Anodonta kennerlyi Canal or flume from Tualatin River to Oswego Lake, Clackamas Co., Oregon. USNM 40689 Anodonta nuttalliana Oregon USNM 708329 Anodonta nuttalliana Columbia River USNM 708327 Anodonta nuttalliana Columbia River USNM 60597 Anodonta nuttalliana Waner Lake CAS 5676 Anodonta nuttalliana Portland, Oregon ANSP 242804 Anodonta oregonensis DeLake ANSP 73925 Anodonta oregonensis Klamath Lake, Oregon ANSP 126516 Anodonta oregonensis Oregon ANSP 365821 Anodonta oregonensis Oregon
ANSP 71701 Anodonta oregonensis Pond north of Switzler's Lake, Columbia Slough region, Portland, Oregon ANSP 339462 Anodonta oregonensis upper Klamath Lake, Merril ANSP 73926 Anodonta oregonensis Upper Klamath Lake, Oregon ANSP 192935 Anodonta oregonensis Wahlamet River, Oregon (Willamet?) USNM 708328 Anodonta oregonensis McNary Reservoir USNM 708326 Anodonta oregonensis Columbia River USNM 86432 Anodonta oregonensis Portland USNM 152643 Anodonta oregonensis Elk Creek
83 Catalog # Original ID Location (as written on original museum tag) USNM 7094,5 Anodonta oregonensis Lost River, USNM 894309 Anodonta oregonensis Crump Lake USNM 152847 Anodonta oregonensis Elk Creek USNM 7099 Anodonta oregonensis Pillar Rock USNM 675028 Anodonta oregonensis Devil's Lake USNM 380797 Anodonta oregonensis Slough on Klamath River USNM 414189 Anodonta oregonensis Mill Creek USNM 153000 Anodonta oregonensis Oregon USNM 73943 Anodonta oregonensis Fort George USNM 186132 Anodonta oregonensis Columbia River USNM 519890 Anodonta oregonensis Slough on Klamath River, SW of Klamath Falls, Or USNM 86433 Anodonta oregonensis Fort George USNM 104162 Anodonta oregonensis Dalles USNM 510860 Anodonta oregonensis The Dalles CAS 168-y Anodonta oregonensis Columbia River near Dalles, Oregon CAS 42332 Anodonta oregonensis Columbia River, near Dalles, Oregon CAS 5679 Anodonta oregonensis Columbia River, near The Dalles, Oregon CAS 156397 Anodonta oregonensis Columbia River, Wasco County: near the Dalles CAS 19912 Anodonta oregonensis Klamath Falls, Oregon CAS 24869 Anodonta oregonensis Klamath Lake 1 mile south of Algoma, Oregon Springs CAS 24132 Anodonta oregonensis Klamath Lake, 4.5 miles north(?) or Celgrove CAS 24871 Anodonta oregonensis Lower Klamath, Lake between Kens & Klamath Falls, Oregon Middle Fork, Malheur County, Oregon (older tag: Middle Fork Malheur River, CAS 42300 Anodonta oregonensis Harney County, Oregon) CAS 168-d Anodonta oregonensis Portland, Oregon CAS 29731 Anodonta oregonensis Portland, Oregon CAS 13955 Anodonta oregonensis upper Klamath Lake CAS 42279 Anodonta oregonensis upper Klamath Lake, near Algoma, Oregon CAS 24141 Anodonta oregonensis Wocus Bay, Klamath Lake ANSP 41167 Anodonta oregonensis Willamette River, Oregon ANSP 11262 Anodonta oregonensis cognata Oswego Lakie, Oswego, Clackamas Co., Oregon USNM 124478 Anodonta prototeria Lea South Umpqua River ANSP 41169 Anodonta wahlamatensis Columbia River Slough, Oregon ANSP 71702 Anodonta wahlamatensis Columbia Slough, Oregon, opposite Vancouver, Wash. ANSP 129915 Anodonta wahlamatensis Oregon ANSP 126512 Anodonta wahlamatensis Portland, Oregon ANSP 129911 Anodonta wahlamatensis Columbia River USNM 602587 Anodonta wahlamatensis Bonneville Dam USNM 86370 Anodonta wahlamatensis Oregon USNM 30091 Anodonta wahlamatensis Oregon USNM 847756 Anodonta wahlamatensis Columbia River USNM 86373 Anodonta wahlamatensis Oregon USNM 25680 Anodonta wahlamatensis Oregon CAS 30038 Anodonta wahlametensis Portland, Oregon CAS 30054 Anodonta wahlametensis The Dalles, Oregon CAS 29730 Anodonta wahlametensis The Dalles, Oregon ANSP 111261 Gonidea angulata Canal or flume from Tualatin River to Oswego Lake
84 Catalog # Original ID Location (as written on original museum tag) ANSP 126671 Gonidea angulata "Takima River, W.T." probably Yakima, Washington Territory USNM 652857 Gonidea angulata Powder River USNM 903967 Gonidea angulata John Day River USNM 487757 Gonidea angulata Columbia River USNM 635198 Gonidea angulata Crooked Creek USNM 40665 Gonidea angulata Oregon USNM 677067 Gonidea angulata Snake River, Ontario USNM 309013 Gonidea angulata Owyhee River USNM 677067 Gonidea angulata Snake River, Ontario USNM 309013 Gonidea angulata Owyhee River, near mouth of Jordan River, Oregon USNM 853337 Gonidea angulata Snake River USNM 635199 Gonidea angulata Crooked Creek USNM 487757 Gonidea angulata Columbia River, Bonneville, Oregon USNM 903967 Gonidea angulata John Day River USNM 635198 Gonidea angulata Crooked Creek at US hwy 95 USNM 652857 Gonidea angulata Powder River CAS 223 Gonidea angulata Portland, Oregon CAS 156-5 Gonidea angulata Columbia River at mouth of Willamette River CAS 156-B Gonidea angulata Dalles CAS 42280 Gonidea angulata Middle Fork Malheur River, Harney County CAS 5684 Gonidea angulata Columbia River near Dalles, Oregon CAS SLF#:C-44 Gonidea angulata Yakima River, Riverside CAS SLF#:C-44 Gonidea angulata Yakima River, Sunnyside, Wash. CAS 158-C Gonidea angulata haroldiana Dall Hangmans Creek, Spokane ANSP 90397 M. falcata Johnson Creek some miles above Lorens Ck (5 mi S of Portland) ANSP 141468 M. margaritifera Willamette River, near Portland ANSP 143461 Margaritana 4 mi E. of Salem CAS 8626 Margaritana deltoidea Willamette River, Salem, Oregon CAS 3022 Margaritana falcata Douglas County, Oregon ANSP 345868 Margaritana margaritifera Umpqua River at Winchester ANSP 265567 Margaritana margaritifera Willamette River ANSP 41085 Margaritana margaritifera Willamette River USNM 677376 Margaritana margaritifera Snake River, Ontario USNM 104169 Margaritana margaritifera Portland USNM 74906 Margaritana margaritifera Oregon USNM 40714 Margaritana margaritifera Oregon USNM 86293 Margaritana margaritifera Snake R. USNM 86296 Margaritana margaritifera Scott R. USNM 86299 Margaritana margaritifera Steilacoom USNM 513918 Margaritana margaritifera Prineville USNM 180851 Margaritana margaritifera Columbia R., Portland USNM 41490 Margaritana margaritifera Pudden R., Salem USNM 86301 Margaritana margaritifera Portland USNM 677289 Margaritana margaritifera Snake River, Ontario USNM 677376 Margaritana margaritifera Snake River, Ontario USNM 105629 Margaritana margaritifera Whatcour Riv. USNM 25835 Margaritana margaritifera Snake River (one tag), Steilacoom Creek, Puget's Sound (two tags)
85 Catalog # Original ID Location (as written on original museum tag) USNM 3621 Margaritana margaritifera Steilacoom CAS 205-6 Margaritana margaritifera Oregon CAS 5620 Margaritana margaritifera falcata Dalles Oregon CAS 154-C.W. Margaritana margaritifera falcata Rogue River, 6 miles south of Grants Pass, Oregon CAS 827 Margaritana margaritifera falcata Dredged near junction of Columbia and Willamette River CAS 826CW Margaritana margaritifera falcata Johnson Creek, Portland Oregon CAS 2826 Cf Margaritana margaritifera falcata Ozette River Washington just below outlet of lake ANSP 383276 Margaritifera falcata Lake Creek, Greenleaf ANSP 339339 Margaritifera falcata Siletz River, about 4 miles N Siletz USNM 652837 Margaritifera falcata Deschutes River USNM 771823 Margaritifera falcata Corvallis USNM 477118 Margaritifera falcata Oregon USNM 652837 Margaritifera falcata Oregon USNM 652836 Margaritifera falcata Deschutes R. USNM 652835 Margaritifera falcata Deschutes R. USNM 60878 Margaritifera falcata Oregon USNM 7105 Margaritifera falcata Columbia R. CAS 65868 Margaritifera falcata Carter Lake, West of U.S. Highway 101, Douglas County Oregon CAS 23907 Margaritifera falcata Rogue River, 6 miles south of Grants Pass, Oregon ANSP 141684 Margaritifera margaritifera "S.P. Car Shops. Southeast. Creek from Penayer Spring" ANSP 89252 Margaritifera margaritifera Mr. Lorenso's Bog 5 miles S. of Portland, 1 m E of Willamette ANSP 71704 Margaritifera margaritifera near Portland ANSP 383277 Margaritifera margaritifera Siletz River, Siletz ANSP 41072 Margaritifera margaritifera Spragues River, S. Oregon ANSP 47719 Margaritifera margaritifera Douglas Co., Oregon ANSP 41081 Margaritifera margaritifera Chehalis River, Washington Territory ANSP 41071 Margaritifera margaritifera E. Fork of Gallatin, Fort Ellis USNM 86299 Margaritifera margaritifera Steilacoom USNM 519889 Margaritifera margaritifera Roseburg USNM 86297 Margaritifera margaritifera Columbia R. CAS 154 Margaritifera margaritifera Olequa Creek ANSP 341265 Margaritifera margaritifera falcata South fork of Battle Creek on Bates Road, near Rosedale, Oregon CAS 42323 Margaritifera margaritifera falcata Clackamas River, 1 mile orth of Oregon City CAS 42299 Margaritifera margaritifera falcata Columbia River, Oregon CAS 42278 Margaritifera margaritifera falcata North Umpqua River at Winchester, Oregon CAS 32216 Margaritifera margaritifera falcata Oregon CAS 29731 Margaritifera margaritifera falcata Patricks Creek 1 1/2 miles above Smith River CAS 23907 Margaritifera margaritifera falcata Portland, Oregon ANSP 139181 Unio (M. falcata) Rogue River ANSP 139182 Unio (M. falcata) Umpqua River ANSP 323966 Unio (M. falcata) Umpqua River ANSP 141286 Unio margaritifera Siletz River, Siletz Indian Reservation ANSP 76389 Unio margaritifera Umpqua River USNM 134594 Unio margaritifera Umpqua R. ANSP 79995 Unionidae (M. falcata) Crooked Creek, Albert Lake
86 Appendix 1b. Freshwater mussel occurrences from Oregon found in the USDA Forest Service western mollusk database.
Genus as cited species as cited Location (as written in original publication) Publication Author Date Publication Proceedings of the Boston Alasmodon falcata Wallawalla, Oregon Gould, A.A. 1850 Society of Natural History Proceedings of the Boston Alasmodon falcata Wallawalla, Oregon; Sacramento River, California Gould, A.A. 1850 Society of Natural History Proceedings of the Boston Anodon cognata Nisqually and near Fort Vancouver Gould, A.A. 1850 Society of Natural History Proceedings of the Boston Anodon cognata Nisqually and near Fort Vancouver Gould, A.A. 1850 Society of Natural History Proceedings of the Boston Anodon feminalis Oregon Gould, A.A. 1850 Society of Natural History Proceedings of the Boston Anodon feminalis Oregon Gould, A.A. 1850 Society of Natural History Proceedings of the Zoological Anodon nuttalliana In flumine Wahlamat, Oregon Carpenter, P.P. 1856 Society of London Proceedings of the Zoological Anodon oregonensis In flumine Wahlamat, Oregon Carpenter, P.P. 1856 Society of London Proceedings of the Zoological Anodon wahlamatensis In flumine Wahlamat, Oregon Carpenter, P.P. 1856 Society of London The University of Colorado Anodonta beringiana Ten Mile Lake, Lakeside, north of Coos Bay Henderson, J. 1929 Studies The University of Colorado Anodonta beringiana Flores Lake Henderson, J. 1929 Studies The University of Colorado Anodonta beringiana Upper Klamath Lake Henderson, J. 1929 Studies Journal of Entomology and Anodonta beringiana Elk Creek below a drain Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta beringiana Ten Mile Lake, Lakeside, north of Coos Bay Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta beringiana Flores Lake Ingram, W. M. 1948 Zoology
87 Genus as cited species as cited Location (as written in original publication) Publication Author Date Publication Journal of Entomology and Anodonta beringiana Upper Klamath Lake Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta beringiana Portland Ingram, W. M. 1948 Zoology The University of Colorado Anodonta californiensis a ditch just west of Coquille Henderson, J. 1929 Studies The University of Colorado Anodonta californiensis Blitzen River, near Malheur Lake Henderson, J. 1929 Studies The University of Colorado Anodonta californiensis fossil from the sand dunes of Harney Lake Henderson, J. 1929 Studies Silvies River, 32 miles north and 4 miles The University of Colorado Anodonta californiensis southeast of Burns Henderson, J. 1929 Studies The University of Colorado Anodonta californiensis a large spring five miles southwest of Burns Henderson, J. 1929 Studies Journal of Entomology and Anodonta californiensis from a ditch just west of Coquille Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta californiensis Blitzen River near Malheur Lake Ingram, W. M. 1948 Zoology a creek 45 miles north and four mile southeast of Journal of Entomology and Anodonta californiensis Burns Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta californiensis a large spring five miles southwest of Burns Ingram, W. M. 1948 Zoology The University of Colorado Anodonta kennerlyi Ten Mile Lake, Lakeside, north of Coos Bay Henderson, J. 1929 Studies The University of Colorado Anodonta kennerlyi a pool seven miles north of Albany Henderson, J. 1929 Studies Journal of Entomology and Anodonta kennerlyi Ten Mile Lake, north of Coos Bay Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta kennerlyi Elbow Lake north of Reedsport Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta kennerlyi a pool seven miles north of Albany Ingram, W. M. 1948 Zoology
88 Genus as cited species as cited Location (as written in original publication) Publication Author Date Publication The University of Colorado Anodonta nuttalliana north end of Upper Klamath Lake Henderson, J. 1929 Studies Slow moving streams or lakes and ponds from Anodonta nuttalliana Canada to Mexico Bonnot, Paul 1951 California Fish and Game Journal of Entomology and Anodonta nuttalliana Eugene Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta nuttalliana Upper Klamath Lake Ingram, W. M. 1948 Zoology Willamette River near junction with the Columbia Journal of Entomology and Anodonta nuttalliana River Ingram, W. M. 1948 Zoology The University of Colorado Anodonta oregonensis Klamath River Henderson, J. 1929 Studies The University of Colorado Anodonta oregonensis Upper Klamath Lake Henderson, J. 1929 Studies Journal of Entomology and Anodonta oregonensis Astoria Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta oregonensis Malheur River Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta oregonensis Lakeport Middle Fork Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta oregonensis Upper Klamath Lake Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta oregonensis Klamath River Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta oregonensis Upper Klamath Lake one mile south of Algoma Ingram, W. M. 1948 Zoology Willamatte River near the junction of the Columbia Journal of Entomology and Anodonta oregonensis River Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta oregonensis The Dalles Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta oregonensis Columbia River near The Dalles Ingram, W. M. 1948 Zoology
89 Genus as cited species as cited Location (as written in original publication) Publication Author Date Publication Anodonta oregonensis Astoria, Oregon Henderson, J. 1936 University of Colorado Studies Anodonta oregonensis Lakeport, Oregon Henderson, J. 1936 University of Colorado Studies Anodonta oregonensis The Dalles Henderson, J. 1936 University of Colorado Studies Journal of Entomology and Anodonta wahlamatensis Upper Klamath Lake Ingram, W. M. 1948 Zoology Willamette River near junction with the Columbia Journal of Entomology and Anodonta wahlamatensis River Ingram, W. M. 1948 Zoology Journal of Entomology and Anodonta wahlamatensis The Dalles Ingram, W. M. 1948 Zoology Steep bluffs of the Middle Fork of the Coquille River and in the river, 16 km east of Myrtle Point Gonidea angulata via SR 42 Branson, B. A. and Branson, R. M. 1984 The Veliger The University of Colorado Gonidea angulata Umpqua River at Roseburg Henderson, J. 1929 Studies The University of Colorado Gonidea angulata Silvies River, north and southeast of Burns Henderson, J. 1929 Studies The University of Colorado Gonidea angulata Blitzen River near Malheur Lake Henderson, J. 1929 Studies The University of Colorado Gonidea angulata four miles above LaGrande Henderson, J. 1929 Studies Rogue River, Jedediah Smith State Park and Gonidea angulata vicinity, Del Norte County, California Haas, F. 1954 The Nautilus Freshwater streams and lakes from Canada to Gonidea angulata Mexico Bonnot, Paul 1951 California Fish and Game Journal of Entomology and Gonidea angulata Umpqua River at Rosenburg Ingram, W. M. 1948 Zoology Journal of Entomology and Gonidea angulata Silvies River north and southeat of Burns Ingram, W. M. 1948 Zoology Journal of Entomology and Gonidea angulata mouth of Willamette River, Oregon Ingram, W. M. 1948 Zoology 4 miles above La Grande Blitzen River near Journal of Entomology and Gonidea angulata Malheur Ingram, W. M. 1948 Zoology
90 Genus as cited species as cited Location (as written in original publication) Publication Author Date Publication Journal of Entomology and Gonidea angulata near The Dalles Ingram, W. M. 1948 Zoology Gonidea angulata mouth of Willamette River, Oregon Henderson, J. 1936 University of Colorado Studies Gonidea angulata The Dalles Henderson, J. 1936 University of Colorado Studies Proceedings of the Academy of Natural Sciences of Margaritana margaritifera Klamath River Lea, I. 1856 Philadelphia Proceedings of the Academy of Natural Sciences of Margaritana margaritifera Columbia River Lea, I. 1856 Philadelphia Clear running streams from the Columbia River Margaritana margaritifera south to Southern California Bonnot, Paul 1951 California Fish and Game Steep bluffs of the Middle Fork of the Coquille River and in the river, 16 km east of Myrtle Point Margaritifera margaritifera via SR 42 Branson, B. A. and Branson, R. M. 1984 The Veliger Siuslaw National Forest, 24 km east of Florence via SR 126, along Siuslaw River R 9 W, T 18 S, S Margaritifera margaritifera 6 (county map coordinates) Branson, B. A. and Branson, R. M. 1984 The Veliger Middle Deschutes River, Jefferson County, Oregon near confluence of the Crooked and Bulletin, Musuem of Natural Margaritifera margaritifera Metolius Rivers with the Deschutes River (map) Roscoe, E. J. 1967 History, University of Oregon Willamette River 10 miles south of Corvalis, Margaritifera margaritifera Oregon Meyers, T. R. and Millemann, R. E. 1977 The Journal of Parasitology Margaritifera margaritifera Siletz River Meyers, T. R. and Millemann, R. E. 1977 The Journal of Parasitology The University of Colorado Margaritifera margaritifera Deschutes River at Bend Henderson, J. 1929 Studies The University of Colorado Margaritifera margaritifera Umpqua River at Roseburg Henderson, J. 1929 Studies The University of Colorado Margaritifera margaritifera Umpqua Auto Camp 25 miles south of Roseburg Henderson, J. 1929 Studies The University of Colorado Margaritifera margaritifera North Umpqua River at Winchester Henderson, J. 1929 Studies Margaritifera margaritifera Jenny Creek, between Ashland and Klamath Falls Henderson, J. 1929 The University of Colorado
91 Genus as cited species as cited Location (as written in original publication) Publication Author Date Publication The University of Colorado Margaritifera margaritifera Rogue River, Grants Pass Henderson, J. 1929 Studies The University of Colorado Margaritifera margaritifera Little Spokane River, northeast of Dartford Henderson, J. 1929 Studies Rogue River at Grants Pass, Josephine County, Margaritifera margaritifera Oregon Haas, F. 1954 The Nautilus Rogue River at Grants Pass, Josephine County, Margaritifera margaritifera Oregon Haas, F. 1954 The Nautilus Journal of Entomology and Margaritifera margaritifera East River, Oregon Ingram, W. M. 1948 Zoology Journal of Entomology and Margaritifera margaritifera Buxton River Ingram, W. M. 1948 Zoology Journal of Entomology and Margaritifera margaritifera Rogue River Ingram, W. M. 1948 Zoology Journal of Entomology and Margaritifera margaritifera Necanicium Creek Ingram, W. M. 1948 Zoology Journal of Entomology and Margaritifera margaritifera South Coos River, Oregon Ingram, W. M. 1948 Zoology Journal of Entomology and Margaritifera margaritifera Umpqua River, Cole's Valley Ingram, W. M. 1948 Zoology Journal of Entomology and Margaritifera margaritifera North Umpqua River at Winchester Ingram, W. M. 1948 Zoology Journal of Entomology and Margaritifera margaritifera near mouth of Willamette River Ingram, W. M. 1948 Zoology Journal of Entomology and Margaritifera margaritifera The Dalles Ingram, W. M. 1948 Zoology Journal of Entomology and Margaritifera margaritifera Johnson Creek, West of Portland Ingram, W. M. 1948 Zoology Margaritifera margaritifera East River, Oregon Henderson, J. 1936 University of Colorado Studies Margaritifera margaritifera Necanicum Creek, Clatsop County, Oregon Henderson, J. 1936 University of Colorado Studies Margaritifera margaritifera South Coos River, Oregon Henderson, J. 1936 University of Colorado Studies Margaritifera margaritifera Umpqua River (Cole's Valley) Henderson, J. 1936 University of Colorado Studies
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