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• 1. [Article] On the Validity of the Radiographic Method for Determining Age of Ancient Salmon

  White rings visible on the centrum face of salmon vertebrae with X-rays have been used since the 1980s to age Pacific salmon (Oncorhynchus spp.), which in turn have been used to determine salmon species, ...

  Citation × Citation Citation Abstract Copy Title: On the Validity of the Radiographic Method for Determining Age of Ancient Salmon Author: Hofkamp, Anthony R., Butler, Virginia L. Year: 2017 White rings visible on the centrum face of salmon vertebrae with X-rays have been used since the 1980s to age Pacific salmon (Oncorhynchus spp.), which in turn have been used to determine salmon species, season of capture and season of site occupation. This approach relies on a variety of assumptions, the most fundamental of which is that rings represent true years. Recent aDNA analysis has shown that the X-ray approach has flaws but the source of the error has been unknown. Given the value of reconstructing salmon population demographics and life history from ancient remains, establishing a valid and reliable method of ageing salmon vertebrae is extremely worthwhile. The main goal of our study was to evaluate if X-ray images of ring patterns on vertebrae provide a valid method of estimating fish age. Vertebrae from 66 adult Chinook salmon (O. tshawytscha) of known age were studied with X-rays, thin sections or low-powered (10–30 ×) magnification. We found that the white bands observed in X-rays are structural walls that do not grow annually. While X-rays are not a valid method for ageing salmonids, incremental growth seen on the surface of fish centra shows great promise for reconstructing ancient fish life history. Title: On the Validity of the Radiographic Method for Determining Age of Ancient Salmon Author: Hofkamp, Anthony R., Butler, Virginia L. Year: 2017 White rings visible on the centrum face of salmon vertebrae with X-rays have been used since the 1980s to age Pacific salmon (Oncorhynchus spp.), which in turn have been used to determine salmon species, season of capture and season of site occupation. This approach relies on a variety of assumptions, the most fundamental of which is that rings represent true years. Recent aDNA analysis has shown that the X-ray approach has flaws but the source of the error has been unknown. Given the value of reconstructing salmon population demographics and life history from ancient remains, establishing a valid and reliable method of ageing salmon vertebrae is extremely worthwhile. The main goal of our study was to evaluate if X-ray images of ring patterns on vertebrae provide a valid method of estimating fish age. Vertebrae from 66 adult Chinook salmon (O. tshawytscha) of known age were studied with X-rays, thin sections or low-powered (10–30 ×) magnification. We found that the white bands observed in X-rays are structural walls that do not grow annually. While X-rays are not a valid method for ageing salmonids, incremental growth seen on the surface of fish centra shows great promise for reconstructing ancient fish life history. Close

• 2. [Article] Where Have All the Native Fish Gone? The Fate of Fish that Lewis and Clark Encountered on the Lower Columbia River

  As part of a special issue of the 'Oregon Historical Quarterly,' discusses the native species of fish in the lower Columbia River described by Meriwether Lewis and William Clark in 1805-06. They identified ...

  Citation × Citation Citation Abstract Copy Title: Where Have All the Native Fish Gone? The Fate of Fish that Lewis and Clark Encountered on the Lower Columbia River Author: Butler, Virginia L. Year: 2004 As part of a special issue of the 'Oregon Historical Quarterly,' discusses the native species of fish in the lower Columbia River described by Meriwether Lewis and William Clark in 1805-06. They identified red charr, salmon trout, sturgeon, anchovy, skeet, and other fish that Indians caught and used as trade items with the Corps of Discovery. However, editors of the Lewis and Clark journals have often erred in identifying the fish Lewis and Clark described; the challenge in identifying anadromous fish lies in changing coloration, markings, and examination of habitat. There has been a drastic decline of native fish since 1805 and a growing dominance of exotic species. Title: Where Have All the Native Fish Gone? The Fate of Fish that Lewis and Clark Encountered on the Lower Columbia River Author: Butler, Virginia L. Year: 2004 As part of a special issue of the 'Oregon Historical Quarterly,' discusses the native species of fish in the lower Columbia River described by Meriwether Lewis and William Clark in 1805-06. They identified red charr, salmon trout, sturgeon, anchovy, skeet, and other fish that Indians caught and used as trade items with the Corps of Discovery. However, editors of the Lewis and Clark journals have often erred in identifying the fish Lewis and Clark described; the challenge in identifying anadromous fish lies in changing coloration, markings, and examination of habitat. There has been a drastic decline of native fish since 1805 and a growing dominance of exotic species. Close

• 3. [Article] Aboriginal Fisheries of the Lower Columbia River

  This chapter, included in Chinookan Peoples of the Lower Columbia, published by the University of Washington Press in 2013, explores the aboriginal fisheries of the Lower Columbia River. The authors reviewed ...

  Citation × Citation Citation Abstract Copy Title: Aboriginal Fisheries of the Lower Columbia River Author: Butler, Virginia L., Martin, Michael A. Year: 2013 This chapter, included in Chinookan Peoples of the Lower Columbia, published by the University of Washington Press in 2013, explores the aboriginal fisheries of the Lower Columbia River. The authors reviewed ethnohistorical accounts and studies of archaeological sites to create a complex picture of Columbia River fisheries that challenges the prevailing view among anthropologists that salmon was the primary and predominant fishery among Chinookan peoples. The authors show that 19th century Native fishers targeted virtually all native fish species in the Lower Columbia River, and employed a wide range of strategies and tactics to acquire and process fish. Title: Aboriginal Fisheries of the Lower Columbia River Author: Butler, Virginia L., Martin, Michael A. Year: 2013 This chapter, included in Chinookan Peoples of the Lower Columbia, published by the University of Washington Press in 2013, explores the aboriginal fisheries of the Lower Columbia River. The authors reviewed ethnohistorical accounts and studies of archaeological sites to create a complex picture of Columbia River fisheries that challenges the prevailing view among anthropologists that salmon was the primary and predominant fishery among Chinookan peoples. The authors show that 19th century Native fishers targeted virtually all native fish species in the Lower Columbia River, and employed a wide range of strategies and tactics to acquire and process fish. Close