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1. [Image] Federal Register - Endangered and Threatened Wildlife and Plants; Notice of 90-Day Finding on a Petition to Delist the Lost River Sucker and Shortnose Sucker


	Only portions of issues of the Federal Register are available in the Klamath Waters Digital Library. Includes bibliographical reference; 50 CFR Part 17; Action: Notice of 90-day petition finding; “FR Doc. ...
	Citation Citation Citation Abstract Copy Title: Federal Register - Endangered and Threatened Wildlife and Plants; Notice of 90-Day Finding on a Petition to Delist the Lost River Sucker and Shortnose Sucker Year: 2002, 2008, 2005 Only portions of issues of the Federal Register are available in the Klamath Waters Digital Library. Includes bibliographical reference; 50 CFR Part 17; Action: Notice of 90-day petition finding; “FR Doc. 02-12123 Filed 5-13-02: 8:45 a.m.;” See the Federal Register at http://www.gpoaccess.gov/fr/advanced.html Title: Federal Register - Endangered and Threatened Wildlife and Plants; Notice of 90-Day Finding on a Petition to Delist the Lost River Sucker and Shortnose Sucker Year: 2002, 2008, 2005 Only portions of issues of the Federal Register are available in the Klamath Waters Digital Library. Includes bibliographical reference; 50 CFR Part 17; Action: Notice of 90-day petition finding; “FR Doc. 02-12123 Filed 5-13-02: 8:45 a.m.;” See the Federal Register at http://www.gpoaccess.gov/fr/advanced.html

2. [Image] Federal Register - Endangered and Threatened Wildlife and Plants; Determination of Endangered Status of the Shortnose Sucker and the Lost River Sucker


	The Service determines endangered status for the shortnose sucker [Chasmistes brevirostris) and Lost River sucker [Deltistes luxatus), fishes restricted to the Klamath Basin of south-central Oregon and ...
	Citation Citation Citation Abstract Copy Title: Federal Register - Endangered and Threatened Wildlife and Plants; Determination of Endangered Status of the Shortnose Sucker and the Lost River Sucker Author: Williams, Jack E. Year: 1988, 2008, 2005 The Service determines endangered status for the shortnose sucker [Chasmistes brevirostris) and Lost River sucker [Deltistes luxatus), fishes restricted to the Klamath Basin of south-central Oregon and north-central California. Dams, draining of marshes, diversion of rivers and dredging of lakes have reduced the range and numbers of both species by more than 95 percent. Remaining populations are composed of older individuals with little or no successful recruitment for many years. Both species are jeopardized by continued loss of habitat, hybridization with more common closely related species, competition and predation by exotic species, and insularization of remaining habitats. This rule implements the protection provided by the Endangered Species Act of 1973, as amended, for the shortnose sucker and Lost River sucker Title: Federal Register - Endangered and Threatened Wildlife and Plants; Determination of Endangered Status of the Shortnose Sucker and the Lost River Sucker Author: Williams, Jack E. Year: 1988, 2008, 2005 The Service determines endangered status for the shortnose sucker [Chasmistes brevirostris) and Lost River sucker [Deltistes luxatus), fishes restricted to the Klamath Basin of south-central Oregon and north-central California. Dams, draining of marshes, diversion of rivers and dredging of lakes have reduced the range and numbers of both species by more than 95 percent. Remaining populations are composed of older individuals with little or no successful recruitment for many years. Both species are jeopardized by continued loss of habitat, hybridization with more common closely related species, competition and predation by exotic species, and insularization of remaining habitats. This rule implements the protection provided by the Endangered Species Act of 1973, as amended, for the shortnose sucker and Lost River sucker

3. [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.