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• 1. [Article] Source of cobalt-60 and migrations of albacore off the west coast of north America

  Citation × Citation Citation Abstract Copy Title: Source of cobalt-60 and migrations of albacore off the west coast of north America Author: Pearcy, William G., Krygier, Earl E. Title: Source of cobalt-60 and migrations of albacore off the west coast of north America Author: Pearcy, William G., Krygier, Earl E. Close

• 2. [Article] Ocean distribution of the American shad (Alosa sapidissima) along the Pacific coast of North America

  We examined the incidental catches of American shad (Alosa sapidissima) taken during research cruises and in commercial and recreational landings along the Pacific coast of North America during over 30 ...

  Citation × Citation Citation Abstract Copy Title: Ocean distribution of the American shad (Alosa sapidissima) along the Pacific coast of North America Author: Fisher, Joseph P., Pearcy, William G. We examined the incidental catches of American shad (Alosa sapidissima) taken during research cruises and in commercial and recreational landings along the Pacific coast of North America during over 30 years of sampling. Shad, an introduced species, was mainly found over the shallow continental shelf, and largest catches and highest frequency of occurrences were found north of central Oregon, along the coasts of Washington and Vancouver Island, and in California around San Francisco Bay. Migrations to the north off Washington and Vancouver were seen during spring to fall, but we found no evidence for large-scale seasonal migrations to the south during the fall or winter. The average weight of shad increased in deeper water. Sizes were also larger in early years of the study. Most were caught over a wide range of sea surface temperatures (11–17°C) and bottom temperatures (6.4–8.0°C). Abundance of shad on the continental shelf north of 44°N was highly correlated with counts of shad at Bonneville Dam on the Columbia River in the same year. Counts were negatively related to average weights and also negatively correlated with the survival of hatchery coho salmon (Oncorhynchus kisutch), indicating that survival of shad is favored by warm ocean conditions. Examining the catch during research cruises and commercial and recreational landings, we concluded that American shad along the Pacific coast have adapted to the prevailing environmental conditions and undertake only moderate seasonal migrations compared with the long seasonal migrations of shad along the Atlantic coast of North America. We suggest that the large spawning populations in the Columbia River and San Francisco Bay areas explain most of the distributional features along the Pacific coast. Title: Ocean distribution of the American shad (Alosa sapidissima) along the Pacific coast of North America Author: Fisher, Joseph P., Pearcy, William G. We examined the incidental catches of American shad (Alosa sapidissima) taken during research cruises and in commercial and recreational landings along the Pacific coast of North America during over 30 years of sampling. Shad, an introduced species, was mainly found over the shallow continental shelf, and largest catches and highest frequency of occurrences were found north of central Oregon, along the coasts of Washington and Vancouver Island, and in California around San Francisco Bay. Migrations to the north off Washington and Vancouver were seen during spring to fall, but we found no evidence for large-scale seasonal migrations to the south during the fall or winter. The average weight of shad increased in deeper water. Sizes were also larger in early years of the study. Most were caught over a wide range of sea surface temperatures (11–17°C) and bottom temperatures (6.4–8.0°C). Abundance of shad on the continental shelf north of 44°N was highly correlated with counts of shad at Bonneville Dam on the Columbia River in the same year. Counts were negatively related to average weights and also negatively correlated with the survival of hatchery coho salmon (Oncorhynchus kisutch), indicating that survival of shad is favored by warm ocean conditions. Examining the catch during research cruises and commercial and recreational landings, we concluded that American shad along the Pacific coast have adapted to the prevailing environmental conditions and undertake only moderate seasonal migrations compared with the long seasonal migrations of shad along the Atlantic coast of North America. We suggest that the large spawning populations in the Columbia River and San Francisco Bay areas explain most of the distributional features along the Pacific coast. Close

• 3. [Article] An epibenthic sampler used to study the ontogeny of vertical migration of pandalus dordani (Decapoda caridea)

  Reprinted from Fishery bulletin: Volume 74(4), pages 994-997.

  Citation × Citation Citation Abstract Copy Title: An epibenthic sampler used to study the ontogeny of vertical migration of pandalus dordani (Decapoda caridea) Author: Rothlisberg, Peter, Pearcy, William G. Reprinted from Fishery bulletin: Volume 74(4), pages 994-997. Title: An epibenthic sampler used to study the ontogeny of vertical migration of pandalus dordani (Decapoda caridea) Author: Rothlisberg, Peter, Pearcy, William G. Reprinted from Fishery bulletin: Volume 74(4), pages 994-997. Close

• 4. [Article] Depth Distribution of Oceanic Shrimps (Decapoda ; Natantia) off Oregon

  Sixteen species of oceanic shrimps, seven Penaeidea and nine Caridea, appeared in 244 collections made within the upper 1500 m at one station in the northeast Pacific off Oregon. Most of the species were ...

  Citation × Citation Citation Abstract Copy Title: Depth Distribution of Oceanic Shrimps (Decapoda ; Natantia) off Oregon Author: Forss, Carl A., Pearcy, William G. Sixteen species of oceanic shrimps, seven Penaeidea and nine Caridea, appeared in 244 collections made within the upper 1500 m at one station in the northeast Pacific off Oregon. Most of the species were primarily mesopelagic in distribution. The most abundant species, Sergestes similis, was the only shrimp common in epipelagic waters at night and the only species clearly demonstrating did vertical migrations. Night catches exceeded day catches in near-surface waters, while day catches exceeded night catches at mid-depths. Sergestes similis migrated into the upper 50 m at night and on one occasion was collected at the surface. Title: Depth Distribution of Oceanic Shrimps (Decapoda ; Natantia) off Oregon Author: Forss, Carl A., Pearcy, William G. Sixteen species of oceanic shrimps, seven Penaeidea and nine Caridea, appeared in 244 collections made within the upper 1500 m at one station in the northeast Pacific off Oregon. Most of the species were primarily mesopelagic in distribution. The most abundant species, Sergestes similis, was the only shrimp common in epipelagic waters at night and the only species clearly demonstrating did vertical migrations. Night catches exceeded day catches in near-surface waters, while day catches exceeded night catches at mid-depths. Sergestes similis migrated into the upper 50 m at night and on one occasion was collected at the surface. Close

• 5. [Article] Upwelling, Columbia River plume and albacore tuna

  Infrared radiometers, photographs, and a multispectral scanner were used in a remote sensing study of the ocean off Oregon during the summer of 1969. Upwelling appeared on infrared temperature maps as ...

  Citation × Citation Citation Abstract Copy Title: Upwelling, Columbia River plume and albacore tuna Author: Mueller, James L., Pearcy, William G. Infrared radiometers, photographs, and a multispectral scanner were used in a remote sensing study of the ocean off Oregon during the summer of 1969. Upwelling appeared on infrared temperature maps as a zone of cold water along the coast and Columbia River water appeared as a warm water "plume". Sharp temperature and color fronts were common. The areal temperature pattern was complex and changed rapidly, undoubtedly influencing the migration and distribution of albacore tuna in Oregon waters. Title: Upwelling, Columbia River plume and albacore tuna Author: Mueller, James L., Pearcy, William G. Infrared radiometers, photographs, and a multispectral scanner were used in a remote sensing study of the ocean off Oregon during the summer of 1969. Upwelling appeared on infrared temperature maps as a zone of cold water along the coast and Columbia River water appeared as a warm water "plume". Sharp temperature and color fronts were common. The areal temperature pattern was complex and changed rapidly, undoubtedly influencing the migration and distribution of albacore tuna in Oregon waters. Close

• 6. [Article] Distribution of hyperiid amphipods off the Oregon coast

  A total of 19 species of hyperiid amphipods was collected from 1963 to 1967 off Oregon. Parathemisto pacifica, Paraphronima gracilis, Streetsia challengeri, Tryphana malmi, Hyperia medusarum, Hyperoche ...

  Citation × Citation Citation Abstract Copy Title: Distribution of hyperiid amphipods off the Oregon coast Author: Lorz, H. (Van Arsdale), Pearcy, William G. A total of 19 species of hyperiid amphipods was collected from 1963 to 1967 off Oregon. Parathemisto pacifica, Paraphronima gracilis, Streetsia challengeri, Tryphana malmi, Hyperia medusarum, Hyperoche medusarum, and Primno macropa were common. New distributional records are reported for Scina crassicornis bermudensis and Lanceola loveni. Abundance and occurrence of common species are lower inshore than offshore suggesting centers of abundance are in offshore-oceanic waters. Yearly changes in occurrence and abundance of hyperiid amphipods inshore may be related to coastal upwelling. There was no evidence for vertical migrations or diel differences at depth intervals of 0-150 m and 150-450 m. Title: Distribution of hyperiid amphipods off the Oregon coast Author: Lorz, H. (Van Arsdale), Pearcy, William G. A total of 19 species of hyperiid amphipods was collected from 1963 to 1967 off Oregon. Parathemisto pacifica, Paraphronima gracilis, Streetsia challengeri, Tryphana malmi, Hyperia medusarum, Hyperoche medusarum, and Primno macropa were common. New distributional records are reported for Scina crassicornis bermudensis and Lanceola loveni. Abundance and occurrence of common species are lower inshore than offshore suggesting centers of abundance are in offshore-oceanic waters. Yearly changes in occurrence and abundance of hyperiid amphipods inshore may be related to coastal upwelling. There was no evidence for vertical migrations or diel differences at depth intervals of 0-150 m and 150-450 m. Close

• 7. [Article] Scattering layers and vertical distribution of oceanic animals off Oregon

  This paper reviews some of the distributional features of vertically migrating micronekton off Oregon; describes a new, conducting-cable, midwater-trawl system using an eight-net, opening-closing cod-end ...

  Citation × Citation Citation Abstract Copy Title: Scattering layers and vertical distribution of oceanic animals off Oregon Author: Pearcy, William G., Mesecar, Roderick S. This paper reviews some of the distributional features of vertically migrating micronekton off Oregon; describes a new, conducting-cable, midwater-trawl system using an eight-net, opening-closing cod-end unit; and gives some preliminary results on trawl catches relative to sound-scattering layers. A variable complex of organisms, including euphausiids, a sergestid shrimp, and mesopelagic fishes, was often common in 12- and 38.5-kHz scattering layers. The depth range of many species was broad, and sometimes the largest catches were made at depths above or below scattering layers. Variability was large among nets that fished either horizontally or vertically during single tows. Title: Scattering layers and vertical distribution of oceanic animals off Oregon Author: Pearcy, William G., Mesecar, Roderick S. This paper reviews some of the distributional features of vertically migrating micronekton off Oregon; describes a new, conducting-cable, midwater-trawl system using an eight-net, opening-closing cod-end unit; and gives some preliminary results on trawl catches relative to sound-scattering layers. A variable complex of organisms, including euphausiids, a sergestid shrimp, and mesopelagic fishes, was often common in 12- and 38.5-kHz scattering layers. The depth range of many species was broad, and sometimes the largest catches were made at depths above or below scattering layers. Variability was large among nets that fished either horizontally or vertically during single tows. Close

• 8. [Article] Tagged steelhead trout (Salmo gairdneri richardson) collected in the north Pacific by the Oshoro-Maru, 1980-1981

  Thirteen steelhead trout (Salmo gairdneri) with coded-wire tags (CWT's) were captured in gillnets fished by the Oshoro-Maru in the Gulf of Alaska along 145°W in 1980 and 1981 and along 180° in 1981. These ...

  Citation × Citation Citation Abstract Copy Title: Tagged steelhead trout (Salmo gairdneri richardson) collected in the north Pacific by the Oshoro-Maru, 1980-1981 Author: Masuda, Kiyoshi, Pearcy, William G. Thirteen steelhead trout (Salmo gairdneri) with coded-wire tags (CWT's) were captured in gillnets fished by the Oshoro-Maru in the Gulf of Alaska along 145°W in 1980 and 1981 and along 180° in 1981. These fish originated from hatcheries in Oregon, Washington and Idaho, U.S.A., and British Columbia, Canada. About 7% of all steelhead caught had CWT's One age LO steelhead entered the ocean about two months before it was captured after migrating at sea at least 1,641 km. Scales of the steelhead caught in gillnets indicated that most were "wild", non-hatchery fish, having spent 2 or 3 years in fresh water, and 0, 1 or 2 years in the ocean. Title: Tagged steelhead trout (Salmo gairdneri richardson) collected in the north Pacific by the Oshoro-Maru, 1980-1981 Author: Masuda, Kiyoshi, Pearcy, William G. Thirteen steelhead trout (Salmo gairdneri) with coded-wire tags (CWT's) were captured in gillnets fished by the Oshoro-Maru in the Gulf of Alaska along 145°W in 1980 and 1981 and along 180° in 1981. These fish originated from hatcheries in Oregon, Washington and Idaho, U.S.A., and British Columbia, Canada. About 7% of all steelhead caught had CWT's One age LO steelhead entered the ocean about two months before it was captured after migrating at sea at least 1,641 km. Scales of the steelhead caught in gillnets indicated that most were "wild", non-hatchery fish, having spent 2 or 3 years in fresh water, and 0, 1 or 2 years in the ocean. Close

• 9. [Article] The ocean ecology of salmon in the Northeast Pacific Ocean : an abridged history

  Research on the ecology of salmon in the northeast Pacific Ocean began in the early 20th century. Charles Gilbert and Willis Rich demonstrated the basis for the stock concept and were instrumental in changing ...

  Citation × Citation Citation Abstract Copy Title: The ocean ecology of salmon in the Northeast Pacific Ocean : an abridged history Author: McKinnell, Stewart M., Pearcy, William G. Research on the ecology of salmon in the northeast Pacific Ocean began in the early 20th century. Charles Gilbert and Willis Rich demonstrated the basis for the stock concept and were instrumental in changing common misconceptions of the times. Later in the 1900s, research endeavors, primarily under the auspices of the International North Pacific Fisheries Commission, led to important studies on the distribution and migration of maturing salmon on the high seas. Research on the early juvenile period was initiated later, especially after the 1982-1983 El Niño clearly showed the limits of the ocean's carrying capacity along the west coast of the United States. There is now good evidence for both intra- and interspecific competition among salmon in the open ocean and for correlations between variable physical environments, such as El Ninos and regime shifts, and survival of salmon during early ocean life. How mortality rates are affected by physical forcing, food availability, predation, and food web structure and how these effects will be modified by climate change and global warming are all major challenges for the future. Title: The ocean ecology of salmon in the Northeast Pacific Ocean : an abridged history Author: McKinnell, Stewart M., Pearcy, William G. Research on the ecology of salmon in the northeast Pacific Ocean began in the early 20th century. Charles Gilbert and Willis Rich demonstrated the basis for the stock concept and were instrumental in changing common misconceptions of the times. Later in the 1900s, research endeavors, primarily under the auspices of the International North Pacific Fisheries Commission, led to important studies on the distribution and migration of maturing salmon on the high seas. Research on the early juvenile period was initiated later, especially after the 1982-1983 El Niño clearly showed the limits of the ocean's carrying capacity along the west coast of the United States. There is now good evidence for both intra- and interspecific competition among salmon in the open ocean and for correlations between variable physical environments, such as El Ninos and regime shifts, and survival of salmon during early ocean life. How mortality rates are affected by physical forcing, food availability, predation, and food web structure and how these effects will be modified by climate change and global warming are all major challenges for the future. Close

• 10. [Article] Albacore oceanography off Oregon : 1970

  During July 1970, albacore boats trolling surface jigs (jig boats) had record catches in an area off the mouth of the Columbia River. The jig fishery declined suddenly in late July and was poor throughout ...

  Citation × Citation Citation Abstract Copy Title: Albacore oceanography off Oregon : 1970 Author: Pearcy, William G. During July 1970, albacore boats trolling surface jigs (jig boats) had record catches in an area off the mouth of the Columbia River. The jig fishery declined suddenly in late July and was poor throughout the remainder of the summer. No obvious oceanographic changes were correlated with these drastic changes in fishing success. Favorable water temperatures extended through August, traditionally the month of highest albacore landings in Oregon. Bait boats, which chum with live bait, had good fishing off Oregon from mid-August to October, indicating that the poor success of jig boats during this time was caused by the behavior of albacore relative to surface-trolled fishing gear. It is postulated that albacore descended into subsurface water in response to a change in availability of their preferred prey, the saury; here they were less accessible to jig boats than bait boats. Saury were common in the stomachs of albacore during periods of good jig fishing and were usually the dominant food where high albacore catches were made by our research vessel. The first albacore catches of the season were probably from an area of warm temperature and low salinity representing Columbia River plume water. The subsequent migration to the north appeared to be along the oceanic edge of the plume. In general, high catches by boats were not within the core of the plume but in 15.5°C water, especially in areas where a horizontal thermal gradient was apparent. Title: Albacore oceanography off Oregon : 1970 Author: Pearcy, William G. During July 1970, albacore boats trolling surface jigs (jig boats) had record catches in an area off the mouth of the Columbia River. The jig fishery declined suddenly in late July and was poor throughout the remainder of the summer. No obvious oceanographic changes were correlated with these drastic changes in fishing success. Favorable water temperatures extended through August, traditionally the month of highest albacore landings in Oregon. Bait boats, which chum with live bait, had good fishing off Oregon from mid-August to October, indicating that the poor success of jig boats during this time was caused by the behavior of albacore relative to surface-trolled fishing gear. It is postulated that albacore descended into subsurface water in response to a change in availability of their preferred prey, the saury; here they were less accessible to jig boats than bait boats. Saury were common in the stomachs of albacore during periods of good jig fishing and were usually the dominant food where high albacore catches were made by our research vessel. The first albacore catches of the season were probably from an area of warm temperature and low salinity representing Columbia River plume water. The subsequent migration to the north appeared to be along the oceanic edge of the plume. In general, high catches by boats were not within the core of the plume but in 15.5°C water, especially in areas where a horizontal thermal gradient was apparent. Close