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Development and calibration of bioelectrical impedance analysis as a measure of energetic status of Arctic grayling (Thymallus arcticus)

Electrical measurements are taken on an Arctic grayling to estimate body condition


August 2012 - July 2015


The energetic status of fishes represents energy stored as protein and lipids and reflects the ability of an individual to reproduce, migrate, and transition through life stages, ultimately influencing survival. However, traditional measurement methods, while highly accurate, are time consuming, expensive, and lethal, and nonlethal methods such as condition factor may not adequately characterize energetic status. Development of non-lethal but precise methods, such as biolelectrical impedance analysis (BIA), to estimate Arctic grayling body condition, as well as baseline data on variation in condition across populations in interior Alaska, is needed. This project was a collaboration between the University of Alaska Fairbanks and USGS. We found the BIA approach to provide rapid, precise, and non-lethal estimates of Arctic grayling body condition, and that fish condition varied by sex, season, and the presence of spawning Pacific salmon across interior Alaska river basins. Such an approach may be useful for future work to characterize Arctic grayling bioenergetics and monitor fish condition under a rapidly changing Arctic environment.

Research Products and Activities

Peer Reviewed Publications

  • Falke, J.A., Bailey, L.T., Fraley, K.M., Lunde, M.J., and A.D. Gryska. 2019. Energetic status and bioelectrical impedance modeling of Arctic grayling Thymallus arcticus in interior Alaska rivers. Environmental Biology of Fishes.


  • Fraley, K. M., Lunde, M. J., Bailey, L. T., Falke, J. A., and A. D. Gryska. 2013. Bioelectrical impedance analysis as a measure of energy density in arctic grayling (Thymallus arcticus). Alaska Chapter American Fisheries Society Annual Meeting, Fairbanks, AK, 7-11 October 2013.
  • Bailey, L.T., and J.A. Falke. 2014. Development and calibration of bioelectric impedance analysis as a measure of energetic status of Arctic grayling (Thymallus arcticus). Alaska Chapter American Fisheries Society Annual Meeting, Juneau, Alaska, 21-24 October 2014.

Current Staff

Federal Staff: 95

Masters Students: 239

Phd Students: 142

Post Docs: 53

University Staff: 240

5 Year Summary

Students graduated: 701

Scientific Publications: 1936

Presentations: 4260



Funding Agencies

  • Cooperative Research Units


Cooperative Research Units Program Headquarters Cooperators

  1. U.S. Geological Survey