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John M Caldwell

My goal as a fish biologist with the Western Fisheries Research Center is to conduct applied research that results in information directly useful to managers.

My background is in research, recovery, and management of western native fishes. In Utah I used capture-recapture techniques to estimate abundance and survival of humpback chub, tracked reproduction of stocked razorback sucker, and managed a project focused on monitoring and controlling non-native fish.  In New Mexico, I monitored populations of two pupfish species, used acoustic telemetry to track movements of gray redhorse and blue sucker in a desert stream, determined current distribution of Rio Grande sucker and chub, and worked cooperatively with other agencies to monitor several desert fishes.  For my master’s thesis I determined the habitats used by the Ouachita darter and quantified the variation in the darter assemblage (9 species) along a longitudinal gradient in the Ouachita River of Arkansas.  Additionally, I participated in life cycle monitoring of pacific salmonids in northern California.

Professional Experience

  • 2021 to Present – Fish Biologist, U.S. Geological Survey, Western Fisheries Research Center, Klamath Falls, OR

  • 2017 – 2021 – Fish Biologist II, Utah Division of Wildlife, Native Aquatics Program, Moab, UT

  • 2011 – 2017 – Fish Biologist, New Mexico Department of Game and Fish, Native Fish Program, Santa Fe, NM

  • 2009 – 2011 – Graduate Research Assistant, Fisheries and Wildlife Program, Arkansas Tech University, Russellville, AR

  • 2006 – 2009 – Fisheries Technician, Campbell Timberland Management, LLC., Fort Bragg, CA

  • 2006 – 2006 – Fisheries Technician, Pacific States Marine Fisheries Commission, Fort Bragg, CA

  • 2005 – 2006 – Fish and Wildlife Scientific Aide, California Department of Fish and Wildlife, Heritage and Wild Trout Program, Rancho Cordova, CA

Education and Certifications

  • M.S. 2011. Fisheries and Wildlife Science, Arkansas Tech University, Russellville, AR

  • B.S. 2005. Environmental Resource Management (Wildlife and Fisheries Science minor), Pennsylvania State University, State College, PA

Science and Products

Detections, Physical Captures, Water Quality, and Fish Health associated with Endangered Suckers in Three Net Pens in Upper Klamath Lake, 2020 Detections, Physical Captures, Water Quality, and Fish Health associated with Endangered Suckers in Three Net Pens in Upper Klamath Lake, 2020

To determine how initial length affects survival of captively-reared juvenile suckers, we introduced Passive Integrated Transponder (PIT) tagged juvenile suckers into three net pens in Upper Klamath Lake. The suckers originated from the U.S. Fish and Wildlife Service's Sucker Assisted Rearing Program in Klamath Falls, Oregon, which rears suckers collected as larvae in Upper Klamath Lake...
By
Western Fisheries Research Center, Fish Health Program (FHP), Klamath Falls Field Station (KFFS)

Growth, survival, and cohort formation of juvenile Lost River (Deltistes luxatus) and shortnose suckers (Chasmistes brevirostris) in Upper Klamath Lake, Oregon, and Clear Lake Reservoir, California—2021–22 monitoring report Growth, survival, and cohort formation of juvenile Lost River (Deltistes luxatus) and shortnose suckers (Chasmistes brevirostris) in Upper Klamath Lake, Oregon, and Clear Lake Reservoir, California—2021–22 monitoring report

Executive SummaryThe work reported in this publication provides updated data and interpretation for sampling years 2015 and 2022 of the juvenile monitoring project. The study objectives, background, study area, species description, and methods remained the same or similar throughout the years, while the executive summary, results, and discussion were updated each year. Therefore much of...
Authors
Barbara Martin, John M. Caldwell, Jacob Krause, Alta C. Harris
By
Ecosystems Mission Area, Western Fisheries Research Center

Does release size into net-pens affect survival of captively reared juvenile endangered suckers in Upper Klamath Lake? Does release size into net-pens affect survival of captively reared juvenile endangered suckers in Upper Klamath Lake?

ObjectiveHigh juvenile mortality prevents recruitment into the adult populations of endangered Shortnose Sucker Chasmistes brevirostris and Lost River Sucker Deltistes luxatus in Upper Klamath Lake, Oregon. To address the lack of recruitment, the U.S. Fish and Wildlife Service implemented the Sucker Assisted Rearing Program (SARP). Managers developing the rearing program lack information...
Authors
John Caldwell, Summer Burdick, Jacob Krause, Alta C. Harris
By
Ecosystems Mission Area, Western Fisheries Research Center

Science and Products

Detections, Physical Captures, Water Quality, and Fish Health associated with Endangered Suckers in Three Net Pens in Upper Klamath Lake, 2020 Detections, Physical Captures, Water Quality, and Fish Health associated with Endangered Suckers in Three Net Pens in Upper Klamath Lake, 2020

To determine how initial length affects survival of captively-reared juvenile suckers, we introduced Passive Integrated Transponder (PIT) tagged juvenile suckers into three net pens in Upper Klamath Lake. The suckers originated from the U.S. Fish and Wildlife Service's Sucker Assisted Rearing Program in Klamath Falls, Oregon, which rears suckers collected as larvae in Upper Klamath Lake...
By
Western Fisheries Research Center, Fish Health Program (FHP), Klamath Falls Field Station (KFFS)

Growth, survival, and cohort formation of juvenile Lost River (Deltistes luxatus) and shortnose suckers (Chasmistes brevirostris) in Upper Klamath Lake, Oregon, and Clear Lake Reservoir, California—2021–22 monitoring report Growth, survival, and cohort formation of juvenile Lost River (Deltistes luxatus) and shortnose suckers (Chasmistes brevirostris) in Upper Klamath Lake, Oregon, and Clear Lake Reservoir, California—2021–22 monitoring report

Executive SummaryThe work reported in this publication provides updated data and interpretation for sampling years 2015 and 2022 of the juvenile monitoring project. The study objectives, background, study area, species description, and methods remained the same or similar throughout the years, while the executive summary, results, and discussion were updated each year. Therefore much of...
Authors
Barbara Martin, John M. Caldwell, Jacob Krause, Alta C. Harris
By
Ecosystems Mission Area, Western Fisheries Research Center

Does release size into net-pens affect survival of captively reared juvenile endangered suckers in Upper Klamath Lake? Does release size into net-pens affect survival of captively reared juvenile endangered suckers in Upper Klamath Lake?

ObjectiveHigh juvenile mortality prevents recruitment into the adult populations of endangered Shortnose Sucker Chasmistes brevirostris and Lost River Sucker Deltistes luxatus in Upper Klamath Lake, Oregon. To address the lack of recruitment, the U.S. Fish and Wildlife Service implemented the Sucker Assisted Rearing Program (SARP). Managers developing the rearing program lack information...
Authors
John Caldwell, Summer Burdick, Jacob Krause, Alta C. Harris
By
Ecosystems Mission Area, Western Fisheries Research Center
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