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• 21. [Article] Precipitation characteristics for landslide hazard assessment for the central Oregon Coast Range

  Precipitation data from 1988-1995 for 13 rain gauges of the Department of Forest Engineering rain gauge network, and a longer precipitation record, 1976-1995, at Mapleton were analyzed. The objectives ...

  Citation × Citation Citation Abstract Copy Title: Precipitation characteristics for landslide hazard assessment for the central Oregon Coast Range Author: Surfleet, Christopher G. Precipitation data from 1988-1995 for 13 rain gauges of the Department of Forest Engineering rain gauge network, and a longer precipitation record, 1976-1995, at Mapleton were analyzed. The objectives were to assess the spatial and temporal distribution of precipitation intensity and antecedent precipitation, and understand the role of these characteristics for triggering debris slides from headwalls in the central Oregon Coast Range. Frequency distribution curves and recurrence intervals using a partial-duration series were calculated for the maximum 5-minute, 30 minute, 1 hour, 2 hour, 6 hour precipitation durations and antecedent precipitation index (API) for the rain gauge network and the maximum 1 hour and 2 hour precipitation durations for Mapleton. Isohyet lines showing selected 2-year precipitation intensities and API were used to characterize the spatial distribution of precipitation intensity and API across the central Oregon Coast Range. The effect of elevation on this spatial distribution was investigated. An attempt to quantify the occurrence of high intensity precipitation occurring with high antecedent precipitation, which is hypothesized to trigger debris slides, was done by testing if the highest precipitation intensities (greater than a 1 -year recurrence interval) occurred during the storms with the highest API. API and precipitation intensity were tested for correlation to discern if a particular precipitation duration could be used to predict API, thus make it possible to use a precipitation intensity based threshold to assess the general hazard of landslides. Precipitation intensities associated with selected recurrence intervals vary considerably over the study area. Precipitation values for selected durations and recurrence intervals could vary as much as 50% or larger for selected rain gauge locations. Precipitation intensities are higher in the central portion of the study area, centered around the ridges of the Siuslaw River watershed, with decreasing intensity toward the northern and southern boundaries possibly due to topographic influences. Higher API values are found more frequent where the high precipitation intensity spatial trends exists. Relationships between short duration precipitation intensities with elevation, and API with elevation, within the rain gauge network could not be determined. No single precipitation intensity, including total storm precipitation, showed a strong positive correlation with high API for the entire rain gauge network. It appears that any attempts to predict the precipitation characteristics which trigger headwall failure by a precipitation intensity threshold in the central Oregon Coast Range is not possible. Attempts to assess the risk of headwall failure by high API may be possible. High precipitation intensities occurred with high antecedent precipitation conditions and they occur at the highest antecedent precipitation conditions. Title: Precipitation characteristics for landslide hazard assessment for the central Oregon Coast Range Author: Surfleet, Christopher G. Precipitation data from 1988-1995 for 13 rain gauges of the Department of Forest Engineering rain gauge network, and a longer precipitation record, 1976-1995, at Mapleton were analyzed. The objectives were to assess the spatial and temporal distribution of precipitation intensity and antecedent precipitation, and understand the role of these characteristics for triggering debris slides from headwalls in the central Oregon Coast Range. Frequency distribution curves and recurrence intervals using a partial-duration series were calculated for the maximum 5-minute, 30 minute, 1 hour, 2 hour, 6 hour precipitation durations and antecedent precipitation index (API) for the rain gauge network and the maximum 1 hour and 2 hour precipitation durations for Mapleton. Isohyet lines showing selected 2-year precipitation intensities and API were used to characterize the spatial distribution of precipitation intensity and API across the central Oregon Coast Range. The effect of elevation on this spatial distribution was investigated. An attempt to quantify the occurrence of high intensity precipitation occurring with high antecedent precipitation, which is hypothesized to trigger debris slides, was done by testing if the highest precipitation intensities (greater than a 1 -year recurrence interval) occurred during the storms with the highest API. API and precipitation intensity were tested for correlation to discern if a particular precipitation duration could be used to predict API, thus make it possible to use a precipitation intensity based threshold to assess the general hazard of landslides. Precipitation intensities associated with selected recurrence intervals vary considerably over the study area. Precipitation values for selected durations and recurrence intervals could vary as much as 50% or larger for selected rain gauge locations. Precipitation intensities are higher in the central portion of the study area, centered around the ridges of the Siuslaw River watershed, with decreasing intensity toward the northern and southern boundaries possibly due to topographic influences. Higher API values are found more frequent where the high precipitation intensity spatial trends exists. Relationships between short duration precipitation intensities with elevation, and API with elevation, within the rain gauge network could not be determined. No single precipitation intensity, including total storm precipitation, showed a strong positive correlation with high API for the entire rain gauge network. It appears that any attempts to predict the precipitation characteristics which trigger headwall failure by a precipitation intensity threshold in the central Oregon Coast Range is not possible. Attempts to assess the risk of headwall failure by high API may be possible. High precipitation intensities occurred with high antecedent precipitation conditions and they occur at the highest antecedent precipitation conditions. Close

• 22. [Article] The effect of river discharge and wind forcing on the Oregon coastal ocean during fall and winter

  Freshwater provided from river discharge influences the dynamics and circulation of most continental shelves around the world. It has profound effects on the transport and fate of materials and substances ...

  Citation × Citation Citation Abstract Copy Title: The effect of river discharge and wind forcing on the Oregon coastal ocean during fall and winter Author: Mazzini, Piero Luigi Fernandes Freshwater provided from river discharge influences the dynamics and circulation of most continental shelves around the world. It has profound effects on the transport and fate of materials and substances originated from rivers and estuaries, as well as on the ocean biogeochemistry and marine ecosystems. The effect of buoyancy forcing and its modification by windstress off the Oregon coast are studied here, with an emphasis on the downwelling season (fall/winter). Six years of data are used in this study, from 2006 to 2012, obtained by a network of coastal oceanographic observations. During the downwelling season, buoyancy-forcing resulting from significant freshwater input from multiple river sources along the coast, together with the predominantly downwelling-favorable windstress and the large-scale Davidson Current, drives what we have named the Oregon Coastal Current (OCC). Based on a 2-layer model, the dominant forcing mechanism of the OCC is buoyancy, followed by the Davidson Current, and then the wind stress, accounting for 61% (±22.6%), 26% (±18.6%) and 13% (±11.7%) of the along-shore transports, respectively. The OCC is a surface-trapped coastal current, with transports comparable to the summertime upwelling jet off the Oregon coast. Offshore of the OCC, the seasonal evolution of the salinity field is controlled by different mechanisms at two distinct times: prior and after the remotely forced spring transition (RFST). After the RFST, along-shelf advection of the Columbia River Plume by remotely forced southward currents dominate the salinity variability. Prior to the RFST, this variability is dominated by cross-shelf freshwater fluxes from the OCC, influencing an offshore distance of approximately 33 km from the OCC's edge. The rate-of-change of salinity over this region can be explained in terms of eddy and wind-driven Ekman cross-shelf freshwater fluxes, however it was not possible to distinguish their relative contributions. Based on the estimated freshwater loss from the OCC, a leaking pipe model was developed, and it was estimated that the along-shelf freshwater fluxes through a cross-shelf section off Newport can be explained by the summed discharges from 3-4 rivers upstream, reaching as far as the Siuslaw of Umpqua rivers. Salinity off Oregon is also variable at interannual time scales. Low salinities during the upwelling season (spring/summer), produced by increased river discharges from the Columbia River are correlated to El Niño/La Niña. The lowest salinity recorded off Newport, was registered during an extreme La Niña event of 2011. For the first time the Columbia River Plume was tracked from mid-shelf all the way into the Yaquina Bay estuary. Finally, the effect of wind-forcing and flow-topography interaction are investigated, in a continental shelf in the absence of freshwater input, off the Brazilian coast. Our results demonstrate that on larger scales, the sea surface temperature variability along the coast is mainly controlled by wind-driven upwelling, while upwelling due to flow-topography interaction is responsible for the smaller scale sea surface temperature variability. Title: The effect of river discharge and wind forcing on the Oregon coastal ocean during fall and winter Author: Mazzini, Piero Luigi Fernandes Freshwater provided from river discharge influences the dynamics and circulation of most continental shelves around the world. It has profound effects on the transport and fate of materials and substances originated from rivers and estuaries, as well as on the ocean biogeochemistry and marine ecosystems. The effect of buoyancy forcing and its modification by windstress off the Oregon coast are studied here, with an emphasis on the downwelling season (fall/winter). Six years of data are used in this study, from 2006 to 2012, obtained by a network of coastal oceanographic observations. During the downwelling season, buoyancy-forcing resulting from significant freshwater input from multiple river sources along the coast, together with the predominantly downwelling-favorable windstress and the large-scale Davidson Current, drives what we have named the Oregon Coastal Current (OCC). Based on a 2-layer model, the dominant forcing mechanism of the OCC is buoyancy, followed by the Davidson Current, and then the wind stress, accounting for 61% (±22.6%), 26% (±18.6%) and 13% (±11.7%) of the along-shore transports, respectively. The OCC is a surface-trapped coastal current, with transports comparable to the summertime upwelling jet off the Oregon coast. Offshore of the OCC, the seasonal evolution of the salinity field is controlled by different mechanisms at two distinct times: prior and after the remotely forced spring transition (RFST). After the RFST, along-shelf advection of the Columbia River Plume by remotely forced southward currents dominate the salinity variability. Prior to the RFST, this variability is dominated by cross-shelf freshwater fluxes from the OCC, influencing an offshore distance of approximately 33 km from the OCC's edge. The rate-of-change of salinity over this region can be explained in terms of eddy and wind-driven Ekman cross-shelf freshwater fluxes, however it was not possible to distinguish their relative contributions. Based on the estimated freshwater loss from the OCC, a leaking pipe model was developed, and it was estimated that the along-shelf freshwater fluxes through a cross-shelf section off Newport can be explained by the summed discharges from 3-4 rivers upstream, reaching as far as the Siuslaw of Umpqua rivers. Salinity off Oregon is also variable at interannual time scales. Low salinities during the upwelling season (spring/summer), produced by increased river discharges from the Columbia River are correlated to El Niño/La Niña. The lowest salinity recorded off Newport, was registered during an extreme La Niña event of 2011. For the first time the Columbia River Plume was tracked from mid-shelf all the way into the Yaquina Bay estuary. Finally, the effect of wind-forcing and flow-topography interaction are investigated, in a continental shelf in the absence of freshwater input, off the Brazilian coast. Our results demonstrate that on larger scales, the sea surface temperature variability along the coast is mainly controlled by wind-driven upwelling, while upwelling due to flow-topography interaction is responsible for the smaller scale sea surface temperature variability. Close

• 23. [Article] Seasonal variations in tidal dynamics, water quality and sediments in the Siuslaw Estuary

  Seasonal data on tides, water quality and sediments in the Siuslaw Estuary were collected. Tide and velocity data were analyzed to evaluate damping conditions in the estuary. The system was found to approximate ...

  Citation × Citation Citation Abstract Copy Title: Seasonal variations in tidal dynamics, water quality and sediments in the Siuslaw Estuary Author: Utt, Michael Ernest Seasonal data on tides, water quality and sediments in the Siuslaw Estuary were collected. Tide and velocity data were analyzed to evaluate damping conditions in the estuary. The system was found to approximate a weakly damped standing wave. A strong relationship of damping conditions to river flow was observed. The equation of wave celerity was used to calculate the effective depth of the estuary. Physical water quality data were examined for dependence on tidal conditions and river flow. The relationship of freshwater flow ratio to estuary stratification was evaluated. The mixing conditions in the estuary were found to vary widely with streamflow. Salinity data were used to estimate estuary flushing times. Sediment sample data were examined for the relationship of physical parameters to distance from the estuary inlet and for seasonal changes. Grain size and other parameters were found to be relatively constant in the main channel of the estuary within about eight miles of the inlet. Shoaling conditions in the estuary were evaluated. Title: Seasonal variations in tidal dynamics, water quality and sediments in the Siuslaw Estuary Author: Utt, Michael Ernest Seasonal data on tides, water quality and sediments in the Siuslaw Estuary were collected. Tide and velocity data were analyzed to evaluate damping conditions in the estuary. The system was found to approximate a weakly damped standing wave. A strong relationship of damping conditions to river flow was observed. The equation of wave celerity was used to calculate the effective depth of the estuary. Physical water quality data were examined for dependence on tidal conditions and river flow. The relationship of freshwater flow ratio to estuary stratification was evaluated. The mixing conditions in the estuary were found to vary widely with streamflow. Salinity data were used to estimate estuary flushing times. Sediment sample data were examined for the relationship of physical parameters to distance from the estuary inlet and for seasonal changes. Grain size and other parameters were found to be relatively constant in the main channel of the estuary within about eight miles of the inlet. Shoaling conditions in the estuary were evaluated. Close

• 24. [Article] One-dimensional numerical model test and predictions for the Siuslaw Estuary

  The one-dimensional numerical model developed by Carl R. Goodwin is applied to the Siuslaw estuary. Vertical displacement, horizontal velocity and flow of the water as a function of time and distance from ...

  Citation × Citation Citation Abstract Copy Title: One-dimensional numerical model test and predictions for the Siuslaw Estuary Author: Farreras, Salvador F. The one-dimensional numerical model developed by Carl R. Goodwin is applied to the Siuslaw estuary. Vertical displacement, horizontal velocity and flow of the water as a function of time and distance from the mouth given by the model are compared with field observations taken under different water mixing conditions in the estuary. The model is considered adequate under well mixed and partially mixed conditions, and inadequate under strongly stratified conditions. Estimations of deviations between model predictions and field observations are presented. Nomograms are constructed from model predictions of amplification factors, high water time lags, maximum flood velocities, maximum ebb velocities, low water time lags, maximum flood flows, maximum ebb flows, high slack water time lags and low slack water time lags, as a function of river flow, ocean tidal range and river mile for a range of 0 to 6000 cubic feet per second (0 to 170 cubic meters per second) of river flow, and 1 to 11 feet (0.30 to 3.35 meters) of ocean tidal range. These nomograms are considered adequate for predictive purposes during well mixed and partially mixed conditions of the estuary waters. Title: One-dimensional numerical model test and predictions for the Siuslaw Estuary Author: Farreras, Salvador F. The one-dimensional numerical model developed by Carl R. Goodwin is applied to the Siuslaw estuary. Vertical displacement, horizontal velocity and flow of the water as a function of time and distance from the mouth given by the model are compared with field observations taken under different water mixing conditions in the estuary. The model is considered adequate under well mixed and partially mixed conditions, and inadequate under strongly stratified conditions. Estimations of deviations between model predictions and field observations are presented. Nomograms are constructed from model predictions of amplification factors, high water time lags, maximum flood velocities, maximum ebb velocities, low water time lags, maximum flood flows, maximum ebb flows, high slack water time lags and low slack water time lags, as a function of river flow, ocean tidal range and river mile for a range of 0 to 6000 cubic feet per second (0 to 170 cubic meters per second) of river flow, and 1 to 11 feet (0.30 to 3.35 meters) of ocean tidal range. These nomograms are considered adequate for predictive purposes during well mixed and partially mixed conditions of the estuary waters. Close

• 25. [Article] Cascade Head - Salmon River : land use and ownership plan

  Citation × Citation Citation Abstract Copy Title: Cascade Head - Salmon River : land use and ownership plan Author: United States. Forest Service. Pacific Northwest Region Title: Cascade Head - Salmon River : land use and ownership plan Author: United States. Forest Service. Pacific Northwest Region Close

• 26. [Article] Ecological baselines for Oregon's coast: a report for agencies that manage Oregon's coastal habitats for ecological and economic sustainability, and for all who are interested in the welfare of wildlife that inhabit our coast and its estuaries

  Against the backdrop of growing concern about dead zones, rare and endangered sea mammals, depletion of Oregon’s once‐abundant fish stocks, acidification threatening coastal molluscs, and proposals for ...

  Citation × Citation Citation Abstract Copy Title: Ecological baselines for Oregon's coast: a report for agencies that manage Oregon's coastal habitats for ecological and economic sustainability, and for all who are interested in the welfare of wildlife that inhabit our coast and its estuaries Author: Mrakovcich, Karina Lorenz, Gilden, Jennifer S., Hall, Roberta L., Ebert, Thomas A., Hatch, David R., Smith, Courtland L. Against the backdrop of growing concern about dead zones, rare and endangered sea mammals, depletion of Oregon’s once‐abundant fish stocks, acidification threatening coastal molluscs, and proposals for marine reserves along Oregon’s coastline, a multidisciplinary group of scientists was called together in 2008 to discuss what is known about Oregon’s coastal resources at specific points in the past. They agreed that knowing more about the condition of resources in the past could help state resource agencies understand its ecological potential and such information would be useful in planning restoration projects as well as determining gaps in knowledge that need to be filled. Called together by John Meyer, representing Communication Partnership for Science and the Sea (COMPASS), the group decided to develop an “Ecological Baselines” report on past coastal resources at whatever times empirical data exist. We begin this report with a chapter reviewing archaeological, ethnographic, and historic materials to provide a picture of Oregon’s coastal resources before 1750. Subsequent chapters consider salmon, sea otters, and sub‐tidal sea urchins. The salmon chapter provides details on twentieth century abundance and decline of one of Oregon’s most charismatic and economically important ocean resources. This chapter’s authors also evaluate remedies that have attempted to restore salmon species. Next, the sea otter chapter describes a mammal once abundant but no longer present on the Oregon coast, and discusses what the coast has lost by its demise. A decade ago, the author, a descendant of Aleut and Coos/Siuslaw natives, organized a multi‐disciplinary project, named The Elakha Alliance, to study and consider restoration of this keystone species. The sub‐tidal purple sea urchin, described in our fourth chapter, in contrast to salmon and otter, is so small that the intense labor required to harvest it has protected it from commercial harvesting. However, the urchin is affected by all the forces that impinge on the coast’s ecological web, and warming seas could affect its ability to survive along Oregon’s coast. Not all developments in the past decades have been negative. We discuss major estuary restoration projects on the Salmon River and the Coquille River that show how restoration is working in these areas and that suggest how other estuary restorations could proceed. On Tuesday Feb. 22, 2012, the Oregon legislature passed a bill that will add 38 square miles of marine reserves in Oregon’s territorial waters at five locations. And in our final section, the epilogue discusses a significant new paradigm for understanding the process of ecological collapse, beginning with the removal of top consumers – keystone predators. This multi‐authored review, published in Science in 2011, thereby suggests ecosystem wide strategies for restoration and stability (Estes et al., 2011). Our report on historical, ecological baselines is only a first step in a compilation of information on significant coastal resources that we believe could encourage additional research and longterm strategies for restoration. Title: Ecological baselines for Oregon's coast: a report for agencies that manage Oregon's coastal habitats for ecological and economic sustainability, and for all who are interested in the welfare of wildlife that inhabit our coast and its estuaries Author: Mrakovcich, Karina Lorenz, Gilden, Jennifer S., Hall, Roberta L., Ebert, Thomas A., Hatch, David R., Smith, Courtland L. Against the backdrop of growing concern about dead zones, rare and endangered sea mammals, depletion of Oregon’s once‐abundant fish stocks, acidification threatening coastal molluscs, and proposals for marine reserves along Oregon’s coastline, a multidisciplinary group of scientists was called together in 2008 to discuss what is known about Oregon’s coastal resources at specific points in the past. They agreed that knowing more about the condition of resources in the past could help state resource agencies understand its ecological potential and such information would be useful in planning restoration projects as well as determining gaps in knowledge that need to be filled. Called together by John Meyer, representing Communication Partnership for Science and the Sea (COMPASS), the group decided to develop an “Ecological Baselines” report on past coastal resources at whatever times empirical data exist. We begin this report with a chapter reviewing archaeological, ethnographic, and historic materials to provide a picture of Oregon’s coastal resources before 1750. Subsequent chapters consider salmon, sea otters, and sub‐tidal sea urchins. The salmon chapter provides details on twentieth century abundance and decline of one of Oregon’s most charismatic and economically important ocean resources. This chapter’s authors also evaluate remedies that have attempted to restore salmon species. Next, the sea otter chapter describes a mammal once abundant but no longer present on the Oregon coast, and discusses what the coast has lost by its demise. A decade ago, the author, a descendant of Aleut and Coos/Siuslaw natives, organized a multi‐disciplinary project, named The Elakha Alliance, to study and consider restoration of this keystone species. The sub‐tidal purple sea urchin, described in our fourth chapter, in contrast to salmon and otter, is so small that the intense labor required to harvest it has protected it from commercial harvesting. However, the urchin is affected by all the forces that impinge on the coast’s ecological web, and warming seas could affect its ability to survive along Oregon’s coast. Not all developments in the past decades have been negative. We discuss major estuary restoration projects on the Salmon River and the Coquille River that show how restoration is working in these areas and that suggest how other estuary restorations could proceed. On Tuesday Feb. 22, 2012, the Oregon legislature passed a bill that will add 38 square miles of marine reserves in Oregon’s territorial waters at five locations. And in our final section, the epilogue discusses a significant new paradigm for understanding the process of ecological collapse, beginning with the removal of top consumers – keystone predators. This multi‐authored review, published in Science in 2011, thereby suggests ecosystem wide strategies for restoration and stability (Estes et al., 2011). Our report on historical, ecological baselines is only a first step in a compilation of information on significant coastal resources that we believe could encourage additional research and longterm strategies for restoration. Close

• 27. [Article] Fish and wildlife resources of the Cascade Head Scenic-Research Area

  "Fish and wildlife species using the Area were identified. Information on occurrence, abundance, habitats, status, recreational or commercial use, and economic value of these species is presented." (p.1) ...

  Citation × Citation Citation Abstract Copy Title: Fish and wildlife resources of the Cascade Head Scenic-Research Area Author: Siuslaw National Forest (Or.), Silovsky, Gene D. "Fish and wildlife species using the Area were identified. Information on occurrence, abundance, habitats, status, recreational or commercial use, and economic value of these species is presented." (p.1) Includes map showing bald eagle and seabird nesting sites. Title: Fish and wildlife resources of the Cascade Head Scenic-Research Area Author: Siuslaw National Forest (Or.), Silovsky, Gene D. "Fish and wildlife species using the Area were identified. Information on occurrence, abundance, habitats, status, recreational or commercial use, and economic value of these species is presented." (p.1) Includes map showing bald eagle and seabird nesting sites. Close

• 28. [Article] Salmon River Estuary hydrographic survey and analysis

  Best scan available. Copy scanned is a photocopy of the original. Some pages are dark and have missing or skewed text.

  Citation × Citation Citation Abstract Copy Title: Salmon River Estuary hydrographic survey and analysis Author: Philip Williams & Associates, Coulton, Kevin G., Siuslaw National Forest (Or.), Crane & Merseth Best scan available. Copy scanned is a photocopy of the original. Some pages are dark and have missing or skewed text. Title: Salmon River Estuary hydrographic survey and analysis Author: Philip Williams & Associates, Coulton, Kevin G., Siuslaw National Forest (Or.), Crane & Merseth Best scan available. Copy scanned is a photocopy of the original. Some pages are dark and have missing or skewed text. Close

• 29. [Article] Damage to clam beds in Siuslaw Bay by tidal wave on March 27, 1964 : Information report

  This is a report of an investigation of possible damage to shellfish in the Siuslaw River estuary following the tsunami of March 27, 1964. Investigators did find some damage to clam beds, "However, the ...

  Citation × Citation Citation Abstract Copy Title: Damage to clam beds in Siuslaw Bay by tidal wave on March 27, 1964 : Information report Author: DeBen, Waldemar A., Stewart, Nelson E., Oregon. Fish Commission. Shellfish Investigations This is a report of an investigation of possible damage to shellfish in the Siuslaw River estuary following the tsunami of March 27, 1964. Investigators did find some damage to clam beds, "However, the damage was not extensive and was limited primarily to the area around runoff channels." Includes map of clam beds surveyed. This is the best possible copy. Title: Damage to clam beds in Siuslaw Bay by tidal wave on March 27, 1964 : Information report Author: DeBen, Waldemar A., Stewart, Nelson E., Oregon. Fish Commission. Shellfish Investigations This is a report of an investigation of possible damage to shellfish in the Siuslaw River estuary following the tsunami of March 27, 1964. Investigators did find some damage to clam beds, "However, the damage was not extensive and was limited primarily to the area around runoff channels." Includes map of clam beds surveyed. This is the best possible copy. Close

• 30. [Article] Shellfish investigation progress report: no.26 (Jan-May 1952)

  This investigation focuses on growth and survival of Pacific razor clams, measuring clams from multiple sites. It tracks the length frequencies of clams recorded, as well as length-live weight relationships. ...

  Citation × Citation Citation Abstract Copy Title: Shellfish investigation progress report: no.26 (Jan-May 1952) Author: Oregon. Fish Commission This investigation focuses on growth and survival of Pacific razor clams, measuring clams from multiple sites. It tracks the length frequencies of clams recorded, as well as length-live weight relationships. This report also includes data on number of crab pots being fished between the Columbia and Siuslaw Rivers in April, 1952. Finally, it includes a short update on the bay clam investigations going on at the time. Title: Shellfish investigation progress report: no.26 (Jan-May 1952) Author: Oregon. Fish Commission This investigation focuses on growth and survival of Pacific razor clams, measuring clams from multiple sites. It tracks the length frequencies of clams recorded, as well as length-live weight relationships. This report also includes data on number of crab pots being fished between the Columbia and Siuslaw Rivers in April, 1952. Finally, it includes a short update on the bay clam investigations going on at the time. Close