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1. [Image] Terminal Moraines


	Image Description from historic lecture booklet: "The thick drift accumulated beneath the end of a valley glacier, or beneath the edge of an ice sheet, is a terminal moraine. At each halt of the receding ...
	Citation Citation Citation Abstract Copy Title: Terminal Moraines Year: 1915 Image Description from historic lecture booklet: "The thick drift accumulated beneath the end of a valley glacier, or beneath the edge of an ice sheet, is a terminal moraine. At each halt of the receding ice sheet a terminal moraine was built with lobes extending down the valleys. These moraines are low, hummocky hills, with enclosed basins, or kettles often occupied by ponds. We have seen these proofs of the great ice sheet of North America that developed during the glacial period. Let us now look at some of the glaciers of the present time." Title: Terminal Moraines Year: 1915 Image Description from historic lecture booklet: "The thick drift accumulated beneath the end of a valley glacier, or beneath the edge of an ice sheet, is a terminal moraine. At each halt of the receding ice sheet a terminal moraine was built with lobes extending down the valleys. These moraines are low, hummocky hills, with enclosed basins, or kettles often occupied by ponds. We have seen these proofs of the great ice sheet of North America that developed during the glacial period. Let us now look at some of the glaciers of the present time."

2. [Image] Glacial Period


	Image Description from historic lecture booklet: "The land waste and the land surfaces of the United States often resemble those found in a region of present glaciers. This is so widely true as to show ...
	Citation Citation Citation Abstract Copy Title: Glacial Period Year: 1915 Image Description from historic lecture booklet: "The land waste and the land surfaces of the United States often resemble those found in a region of present glaciers. This is so widely true as to show that great glaciers once covered the face of the country. We are now to look at some of the proofs of these earlier glaciers. At the beginning of the period of cold, deep snows gathered and ice was formed on broad uplands of Canada. As the cold increased, the area of ice formation grew larger, and the ice also spread by flowing outward about its edges. The ice centers were not among high mountains, but the ice grew in thickness until, like a mass of pitch it was forced to flow by its own weight. It spread in all directions, and the south edge crept out over what is now the boundary of Canada and invaded the region of the United States. How far it reached can best be understood by studying the map. The line of its extreme limit, which geologists have traced with care, traverses the southern border of New England, crosses New Jersey, Pennsylvania, and southwestern New York, and then follows a crooked course north of Missouri and then runs northwest through Nebraska, the Dakotas and Montana. The ice outline had different forms at different times." Title: Glacial Period Year: 1915 Image Description from historic lecture booklet: "The land waste and the land surfaces of the United States often resemble those found in a region of present glaciers. This is so widely true as to show that great glaciers once covered the face of the country. We are now to look at some of the proofs of these earlier glaciers. At the beginning of the period of cold, deep snows gathered and ice was formed on broad uplands of Canada. As the cold increased, the area of ice formation grew larger, and the ice also spread by flowing outward about its edges. The ice centers were not among high mountains, but the ice grew in thickness until, like a mass of pitch it was forced to flow by its own weight. It spread in all directions, and the south edge crept out over what is now the boundary of Canada and invaded the region of the United States. How far it reached can best be understood by studying the map. The line of its extreme limit, which geologists have traced with care, traverses the southern border of New England, crosses New Jersey, Pennsylvania, and southwestern New York, and then follows a crooked course north of Missouri and then runs northwest through Nebraska, the Dakotas and Montana. The ice outline had different forms at different times."

3. [Image] Fire-insect-disease relationships of a lodgepole pine ecosystem in south-central Oregon


	ill.; "July 1985."; "Final report on National Science Foundation Grant DEB-8109813"-- Cover; Includes offprints of several project-related publications by the authors; Includes bibliographical referen...
	Citation Citation Citation Abstract Copy Title: Fire-insect-disease relationships of a lodgepole pine ecosystem in south-central Oregon Author: Gara, Robert I. Year: 1985, 2008 ill.; "July 1985."; "Final report on National Science Foundation Grant DEB-8109813"-- Cover; Includes offprints of several project-related publications by the authors; Includes bibliographical references Title: Fire-insect-disease relationships of a lodgepole pine ecosystem in south-central Oregon Author: Gara, Robert I. Year: 1985, 2008 ill.; "July 1985."; "Final report on National Science Foundation Grant DEB-8109813"-- Cover; Includes offprints of several project-related publications by the authors; Includes bibliographical references

4. [Image] Report of 1994 Workshop on the Correlation of Marine and Terrestrial Records of Climate Changes in the Western United States


	Imprint from transmittal sheet; Distributed to depository libraries in microfiche; Shipping list no.: 97-0071-M; One ill. on 1 folded leaf in pocket; Includes bibliographical references
	Citation Citation Citation Abstract Copy Title: Report of 1994 Workshop on the Correlation of Marine and Terrestrial Records of Climate Changes in the Western United States Author: Workshop on the Correlation of Marine and Terrestrial Records of Climate Changes in the Western U.S. (3rd : 1994 : Watsonville, Calif.) Year: 1996, 2007, 2005 Imprint from transmittal sheet; Distributed to depository libraries in microfiche; Shipping list no.: 97-0071-M; One ill. on 1 folded leaf in pocket; Includes bibliographical references Title: Report of 1994 Workshop on the Correlation of Marine and Terrestrial Records of Climate Changes in the Western United States Author: Workshop on the Correlation of Marine and Terrestrial Records of Climate Changes in the Western U.S. (3rd : 1994 : Watsonville, Calif.) Year: 1996, 2007, 2005 Imprint from transmittal sheet; Distributed to depository libraries in microfiche; Shipping list no.: 97-0071-M; One ill. on 1 folded leaf in pocket; Includes bibliographical references

5. [Image] An assessment of ecosystem components in the interior Columbia Basin and portions of the Klamath and Great Basins [volume 2]


	Abstract Quigley, Thomas M.; Arbelbide, Sylvia J., tech. eds. 1997. An assessment of ecosystem components in the interior Columbia basin and portions of the Klamath and Great Basins: volume 2. Gen. Tech. ...
	Citation Citation Citation Abstract Copy Title: An assessment of ecosystem components in the interior Columbia Basin and portions of the Klamath and Great Basins [volume 2] Author: Quigley, Thomas Milton; Arbelbide, S. J. (Sylvia J.) Year: 1997, 2008, 2005 Abstract Quigley, Thomas M.; Arbelbide, Sylvia J., tech. eds. 1997. An assessment of ecosystem components in the interior Columbia basin and portions of the Klamath and Great Basins: volume 2. Gen. Tech. Rep. PNW-GTR-405. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 4 vol. (Quigley, Thomas M., tech. ed.; The Interior Columbia Basin Ecosystem Management Project: Scientific Assessment). The Assessment of Ecosystem Components in the Interior Columbia Basin and Portions of the Klamath and Great Basins provides detailed information about current conditions and trends for the biophysical and social systems within the Basin. This information can be used by land managers to develop broad land management goals and priorities and provides the context for decisions specific to smaller geographic areas. The Assessment area covers about 8 percent of the U.S. land area, 24 percent of the Nations National Forest System lands, 10 percent of the Nations BLM-administered lands, and contains about 1.2 percent of the Nations population. This results in a population density that is less than one-sixth of the U.S. average. The area has experienced recent, rapid population growth and generally has a robust, diverse economy. As compared to historic conditions, the terrestrial, aquatic, forest, and rangeland systems have undergone dramatic changes. Forested landscapes are more susceptible to fire, insect, and disease than under historic conditions. Rangelands are highly susceptible to noxious weed invasion. The disturbance regimes that operate on forest and rangeland have changed substantially, with lethal fires dominating many areas where non-lethal fires were the norm historically. Terrestrial habitats that have experienced the greatest decline include the native grassland, native shrubland, and old forest structures. There are areas within the Assessment area that have higher diversity than others. Aquatic systems are now more fragmented and isolated than historically and the introduction of non-native fish species has complicated current status of native fishes. Core habitat and population centers do remain as building blocks for restoration. Social and economic conditions within the Assessment area vary considerably, depending to a great extent on population, diversity of employment opportunities, and changing demographics. Those counties with the higher population densities and greater diversity of employment opportunities are generally more resilient to economic downturns. This Assessment provides a rich information base, including over 170 mapped themes with associated models and databases, from which future decisions can benefit. Keywords: Columbia basin, biophysical systems, social systems, ecosystem. Title: An assessment of ecosystem components in the interior Columbia Basin and portions of the Klamath and Great Basins [volume 2] Author: Quigley, Thomas Milton; Arbelbide, S. J. (Sylvia J.) Year: 1997, 2008, 2005 Abstract Quigley, Thomas M.; Arbelbide, Sylvia J., tech. eds. 1997. An assessment of ecosystem components in the interior Columbia basin and portions of the Klamath and Great Basins: volume 2. Gen. Tech. Rep. PNW-GTR-405. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 4 vol. (Quigley, Thomas M., tech. ed.; The Interior Columbia Basin Ecosystem Management Project: Scientific Assessment). The Assessment of Ecosystem Components in the Interior Columbia Basin and Portions of the Klamath and Great Basins provides detailed information about current conditions and trends for the biophysical and social systems within the Basin. This information can be used by land managers to develop broad land management goals and priorities and provides the context for decisions specific to smaller geographic areas. The Assessment area covers about 8 percent of the U.S. land area, 24 percent of the Nations National Forest System lands, 10 percent of the Nations BLM-administered lands, and contains about 1.2 percent of the Nations population. This results in a population density that is less than one-sixth of the U.S. average. The area has experienced recent, rapid population growth and generally has a robust, diverse economy. As compared to historic conditions, the terrestrial, aquatic, forest, and rangeland systems have undergone dramatic changes. Forested landscapes are more susceptible to fire, insect, and disease than under historic conditions. Rangelands are highly susceptible to noxious weed invasion. The disturbance regimes that operate on forest and rangeland have changed substantially, with lethal fires dominating many areas where non-lethal fires were the norm historically. Terrestrial habitats that have experienced the greatest decline include the native grassland, native shrubland, and old forest structures. There are areas within the Assessment area that have higher diversity than others. Aquatic systems are now more fragmented and isolated than historically and the introduction of non-native fish species has complicated current status of native fishes. Core habitat and population centers do remain as building blocks for restoration. Social and economic conditions within the Assessment area vary considerably, depending to a great extent on population, diversity of employment opportunities, and changing demographics. Those counties with the higher population densities and greater diversity of employment opportunities are generally more resilient to economic downturns. This Assessment provides a rich information base, including over 170 mapped themes with associated models and databases, from which future decisions can benefit. Keywords: Columbia basin, biophysical systems, social systems, ecosystem.

6. [Image] Soils of the Klamath Indian Reservation; interim report, June 11, 1958


	TABLE OF CONTENTS PART I INTRODUCTION 18 - 11 History and ethnology 18 Irrigated area table 19 Cultural geography 19 General physiographic features 262e . .3 Physiographic areas and farming 1d CLIMATE ...
	Citation Citation Citation Abstract Copy Title: Soils of the Klamath Indian Reservation; interim report, June 11, 1958 Author: United States. Bureau of Indian Affairs Year: 1958, 2005, 2004 TABLE OF CONTENTS PART I INTRODUCTION 18 - 11 History and ethnology 18 Irrigated area table 19 Cultural geography 19 General physiographic features 262e . .3 Physiographic areas and farming 1d CLIMATE 182 - 18 Climatic table, Sprague River, Oregon 185 Precipitation table , Chiloquin, Oregon 186 Temperature table, Chiloquin, Oregon 187 Climatic table, Fort Klamath, Oregon 188 VEGETATION 189 - 25 GEOLOGY 196 - 51 Hydrography: rivers, lakes, marshes, ground water 196 Relief and geological formations. 262e .32 Diatomite - tuff formation 262e . 1c4 Pliocene sediments of the Modoc Point area 262e.. 37 Faulted tuff formation 1c9 Pumice tuff formation.. 1d0 Pumice mantle and pumice flows ........ 262e.... .........40 Table of chemical analyses of pumice and scoria 1d5 Geology Map 262e . 262e 221 BIBLIOGRAPHY 262e 262e...52 PART II DESCRIPTIONS OF SOILS 223 - 60 Classification and survey 262e 262e.. 262e... 53 Soil profile and nomenclature. .... 262e...53 Chestnut Soils 262e 224 "Western" Brown Forest Soils 225 Regosol Soils . . 262e. 262e......56 Solonetz Soils 262e.....57 Halomorphic Soils 262e 228 Hydromorphic Soils 262e... 229 Soil Association Map 262e 229 KEY TO SOIL SERIES 262e61 - 63 SOIL SERIES AND MAPPING UNIT DESCRIPTIONS 134 ~ 254 APPENDIX 1955 - 297 Soil Series and mapping unit index. 2620. . . . 255 Glossary of terms 263f 262e. . . . 272 Table of soil analyses (Oregon State College)... 1989 Table of irrigation water quality (Oregon State College) 1990 Table of conductivity and reaction. . . . 1991 Table of resistance of saturated paste 262e296 Title: Soils of the Klamath Indian Reservation; interim report, June 11, 1958 Author: United States. Bureau of Indian Affairs Year: 1958, 2005, 2004 TABLE OF CONTENTS PART I INTRODUCTION 18 - 11 History and ethnology 18 Irrigated area table 19 Cultural geography 19 General physiographic features 262e . .3 Physiographic areas and farming 1d CLIMATE 182 - 18 Climatic table, Sprague River, Oregon 185 Precipitation table , Chiloquin, Oregon 186 Temperature table, Chiloquin, Oregon 187 Climatic table, Fort Klamath, Oregon 188 VEGETATION 189 - 25 GEOLOGY 196 - 51 Hydrography: rivers, lakes, marshes, ground water 196 Relief and geological formations. 262e .32 Diatomite - tuff formation 262e . 1c4 Pliocene sediments of the Modoc Point area 262e.. 37 Faulted tuff formation 1c9 Pumice tuff formation.. 1d0 Pumice mantle and pumice flows ........ 262e.... .........40 Table of chemical analyses of pumice and scoria 1d5 Geology Map 262e . 262e 221 BIBLIOGRAPHY 262e 262e...52 PART II DESCRIPTIONS OF SOILS 223 - 60 Classification and survey 262e 262e.. 262e... 53 Soil profile and nomenclature. .... 262e...53 Chestnut Soils 262e 224 "Western" Brown Forest Soils 225 Regosol Soils . . 262e. 262e......56 Solonetz Soils 262e.....57 Halomorphic Soils 262e 228 Hydromorphic Soils 262e... 229 Soil Association Map 262e 229 KEY TO SOIL SERIES 262e61 - 63 SOIL SERIES AND MAPPING UNIT DESCRIPTIONS 134 ~ 254 APPENDIX 1955 - 297 Soil Series and mapping unit index. 2620. . . . 255 Glossary of terms 263f 262e. . . . 272 Table of soil analyses (Oregon State College)... 1989 Table of irrigation water quality (Oregon State College) 1990 Table of conductivity and reaction. . . . 1991 Table of resistance of saturated paste 262e296

7. [Image] The geology and petrography of Crater lake national park


	167, iii p.; xix pl. (incl. 2 maps); Geology by J.S. Diller; Petrography by H.B. Patton; 35.00S
	Citation Citation Citation Abstract Copy Title: The geology and petrography of Crater lake national park Author: Diller, Joseph Silas; Patton, Horace Bushnell Year: 1902, 2006 167, iii p.; xix pl. (incl. 2 maps); Geology by J.S. Diller; Petrography by H.B. Patton; 35.00S Title: The geology and petrography of Crater lake national park Author: Diller, Joseph Silas; Patton, Horace Bushnell Year: 1902, 2006 167, iii p.; xix pl. (incl. 2 maps); Geology by J.S. Diller; Petrography by H.B. Patton; 35.00S

8. [Image] An assessment of ecosystem components in the interior Columbia Basin and portions of the Klamath and Great Basins [volume 1]


	Quigley, Thomas M.; Arbelbide, Sylvia J., tech. eds. 1997. An assessment of ecosystem components in the interior Columbia basin and portions of the Klamath and Great Basins: volume 1. Gen. Tech. Rep. PNW-GTR-405. ...
	Citation Citation Citation Abstract Copy Title: An assessment of ecosystem components in the interior Columbia Basin and portions of the Klamath and Great Basins [volume 1] Author: Quigley, Thomas Milton; Arbelbide, S. J. (Sylvia J.) Year: 1997, 2008, 2005 Quigley, Thomas M.; Arbelbide, Sylvia J., tech. eds. 1997. An assessment of ecosystem components in the interior Columbia basin and portions of the Klamath and Great Basins: volume 1. Gen. Tech. Rep. PNW-GTR-405. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 4 vol. (Quigley, Thomas M., tech. ed.; The Interior Columbia Basin Ecosystem Management Project: Scientific Assessment). The Assessment of Ecosystem Components in the Interior Columbia Basin and Portions of the Klamath and Great Basins provides detailed information about current conditions and trends for the biophysical and social systems within the Basin. This information can be used by land managers to develop broad land management goals and priorities and provides the context for decisions specific to smaller geographic areas. The Assessment area covers about 8 percent of the U.S. land area, 24 percent of the Nation's National Forest System lands, 10 percent of the Nation's BLM-administered lands, and contains about 1.2 percent of the Nation's population. This results in a population density that is less than one-sixth of the U.S. average. The area has experienced recent, rapid population growth and generally has a robust, diverse economy. As compared to historic conditions, the terrestrial, aquatic, forest, and rangeland systems have undergone dramatic changes. Forested landscapes are more susceptible to fire, insect, and disease than under historic conditions. Rangelands are highly susceptible to noxious weed invasion. The disturbance regimes that operate on forest and rangeland have changed substantially, with lethal fires dominating many areas where non-lethal fires were the norm historically. Terrestrial habitats that have experienced the greatest decline include the native grassland, native shrubland, and old forest structures. There are areas within the Assessment area that have higher diversity than others. Aquatic systems are now more fragmented and isolated than historically and the introduction of non-native fish species has complicated current status of native fishes. Core habitat and population centers do remain as building blocks for restoration. Social and economic conditions within the Assessment area vary considerably, depending to a great extent on population, diversity of employment opportunities, and changing demographics. Those counties with the higher population densities and greater diversity of employment opportunities are generally more resilient to economic downturns. This Assessment provides a rich information base, including over 170 mapped themes with associated models and databases, from which future decisions can benefit. Keywords: Columbia basin, biophysical systems, social systems, ecosystem. Title: An assessment of ecosystem components in the interior Columbia Basin and portions of the Klamath and Great Basins [volume 1] Author: Quigley, Thomas Milton; Arbelbide, S. J. (Sylvia J.) Year: 1997, 2008, 2005 Quigley, Thomas M.; Arbelbide, Sylvia J., tech. eds. 1997. An assessment of ecosystem components in the interior Columbia basin and portions of the Klamath and Great Basins: volume 1. Gen. Tech. Rep. PNW-GTR-405. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 4 vol. (Quigley, Thomas M., tech. ed.; The Interior Columbia Basin Ecosystem Management Project: Scientific Assessment). The Assessment of Ecosystem Components in the Interior Columbia Basin and Portions of the Klamath and Great Basins provides detailed information about current conditions and trends for the biophysical and social systems within the Basin. This information can be used by land managers to develop broad land management goals and priorities and provides the context for decisions specific to smaller geographic areas. The Assessment area covers about 8 percent of the U.S. land area, 24 percent of the Nation's National Forest System lands, 10 percent of the Nation's BLM-administered lands, and contains about 1.2 percent of the Nation's population. This results in a population density that is less than one-sixth of the U.S. average. The area has experienced recent, rapid population growth and generally has a robust, diverse economy. As compared to historic conditions, the terrestrial, aquatic, forest, and rangeland systems have undergone dramatic changes. Forested landscapes are more susceptible to fire, insect, and disease than under historic conditions. Rangelands are highly susceptible to noxious weed invasion. The disturbance regimes that operate on forest and rangeland have changed substantially, with lethal fires dominating many areas where non-lethal fires were the norm historically. Terrestrial habitats that have experienced the greatest decline include the native grassland, native shrubland, and old forest structures. There are areas within the Assessment area that have higher diversity than others. Aquatic systems are now more fragmented and isolated than historically and the introduction of non-native fish species has complicated current status of native fishes. Core habitat and population centers do remain as building blocks for restoration. Social and economic conditions within the Assessment area vary considerably, depending to a great extent on population, diversity of employment opportunities, and changing demographics. Those counties with the higher population densities and greater diversity of employment opportunities are generally more resilient to economic downturns. This Assessment provides a rich information base, including over 170 mapped themes with associated models and databases, from which future decisions can benefit. Keywords: Columbia basin, biophysical systems, social systems, ecosystem.

9. [Image] The trout and salmon of the Pacific coast


	This article is an overview of the variety of trout and salmon that are found in Oregon and Washington states.
	Citation Citation Citation Abstract Copy Title: The trout and salmon of the Pacific coast Author: Jordan, David Starr Year: 1906, 2005, 2004 This article is an overview of the variety of trout and salmon that are found in Oregon and Washington states. Title: The trout and salmon of the Pacific coast Author: Jordan, David Starr Year: 1906, 2005, 2004 This article is an overview of the variety of trout and salmon that are found in Oregon and Washington states.

10. [Image] Distribution and biology of suckers in Lower Klamath reservoirs : 1999 final report


	Abstract The objectives of this two-year study (1998-1999) were to document distribution, abundance, age class structure, recruitment success, and habitat use by all life history stages of shortnose and ...
	Citation Citation Citation Abstract Copy Title: Distribution and biology of suckers in Lower Klamath reservoirs : 1999 final report Author: Desjardins, Marc; Markle, Douglas F. Year: 2000, 2005 Abstract The objectives of this two-year study (1998-1999) were to document distribution, abundance, age class structure, recruitment success, and habitat use by all life history stages of shortnose and Lost River suckers in three lower Klamath River hydroelectric reservoirs (J. C. Boyle, Copco, and Iron Gate). Lost River sucker catches were sporadic (only 3 adult individuals total) and the focus of our analyses, therefore, shifted to shortnose suckers. Adult and larval suckers were found in all reservoirs both years. All life history stages (larvae, juveniles and adults) were found in J. C. Boyle during both years and in Copco in 1999. Juvenile suckers were not found in Copco in 1998. The number of adult shortnose suckers was highest in Copco reservoir (n=165), followed by J.C. Boyle (n=50) and Iron Gate (n=22). Larger and older individuals dominated Copco and Iron Gate reservoirs and little size structure was detected. J. C. Boyle tended to have smaller adult shortnose suckers and many size classes were present. Unidentifiable larval suckers were most abundant in Copco reservoir where historic spawning of shortnose suckers has been documented. Larval suckers in Copco and Iron Gate reservoirs were most abundant in mid to late June before quickly disappearing from catches. J. C. Boyle larval suckers peaked in mid July, attained larger sizes, and were caught later in the season. It appeared that recruitment of young-of-the-year suckers only occurred in J. C. Boyle with downstream reservoirs recruiting older individuals, perhaps those that had earlier recruited to J. C. Boyle. Tagging studies could clarify adult recruitment dynamics and an additional study of juvenile recruitment would be needed to confirm these patterns. Predation pressure may be somewhat reduced in J. C. Boyle in comparison to the other reservoirs as its fish community was dominated by native fishes while communities in Copco and Iron Gate reservoirs were dominated by exotic predators. J. C. Boyle also possessed proportionally more littoral habitat, which suggests it may provide a more stable environment for young fishes. However, our sampling was inadequate to demonstrate such relationships due to high variance in larval and juvenile catches and potentially confounding habitat variables. One such variable was water level fluctuations, which could interact with habitat and resource availability in complex ways. For example, water level fluctuations, presumed to have a negative impact, were greatest in J. C. Boyle. Extrapolation from the literature suggests it should have had the poorest habitat for larval and juvenile suckers, but our results indicated J. C. Boyle had the most young suckers. Additional study of the relationships between water level fluctuations, habitat availability, the exotic fish community, and juvenile sucker recruitment would be needed to better understand early life history ecology of endangered lake suckers in these systems. Title: Distribution and biology of suckers in Lower Klamath reservoirs : 1999 final report Author: Desjardins, Marc; Markle, Douglas F. Year: 2000, 2005 Abstract The objectives of this two-year study (1998-1999) were to document distribution, abundance, age class structure, recruitment success, and habitat use by all life history stages of shortnose and Lost River suckers in three lower Klamath River hydroelectric reservoirs (J. C. Boyle, Copco, and Iron Gate). Lost River sucker catches were sporadic (only 3 adult individuals total) and the focus of our analyses, therefore, shifted to shortnose suckers. Adult and larval suckers were found in all reservoirs both years. All life history stages (larvae, juveniles and adults) were found in J. C. Boyle during both years and in Copco in 1999. Juvenile suckers were not found in Copco in 1998. The number of adult shortnose suckers was highest in Copco reservoir (n=165), followed by J.C. Boyle (n=50) and Iron Gate (n=22). Larger and older individuals dominated Copco and Iron Gate reservoirs and little size structure was detected. J. C. Boyle tended to have smaller adult shortnose suckers and many size classes were present. Unidentifiable larval suckers were most abundant in Copco reservoir where historic spawning of shortnose suckers has been documented. Larval suckers in Copco and Iron Gate reservoirs were most abundant in mid to late June before quickly disappearing from catches. J. C. Boyle larval suckers peaked in mid July, attained larger sizes, and were caught later in the season. It appeared that recruitment of young-of-the-year suckers only occurred in J. C. Boyle with downstream reservoirs recruiting older individuals, perhaps those that had earlier recruited to J. C. Boyle. Tagging studies could clarify adult recruitment dynamics and an additional study of juvenile recruitment would be needed to confirm these patterns. Predation pressure may be somewhat reduced in J. C. Boyle in comparison to the other reservoirs as its fish community was dominated by native fishes while communities in Copco and Iron Gate reservoirs were dominated by exotic predators. J. C. Boyle also possessed proportionally more littoral habitat, which suggests it may provide a more stable environment for young fishes. However, our sampling was inadequate to demonstrate such relationships due to high variance in larval and juvenile catches and potentially confounding habitat variables. One such variable was water level fluctuations, which could interact with habitat and resource availability in complex ways. For example, water level fluctuations, presumed to have a negative impact, were greatest in J. C. Boyle. Extrapolation from the literature suggests it should have had the poorest habitat for larval and juvenile suckers, but our results indicated J. C. Boyle had the most young suckers. Additional study of the relationships between water level fluctuations, habitat availability, the exotic fish community, and juvenile sucker recruitment would be needed to better understand early life history ecology of endangered lake suckers in these systems.