Cooperative Fish and Wildlife Research Units Program: Wyoming
Education, Research and Technical Assistance for Managing Our Natural Resources

Wyoming Project

Quantifying age and growth dynamics of key sport fishes in Flaming Gorge Reservoir and Buffalo Bill Reservoir

July 2020 - June 2024


Participating Agencies

  • Wyoming Game and Fish Department

Age and growth data provide fundamental indicators of the environmental and physiological conditions fish experience and are critical to informing fisheries management decisions. Through analyses of age and growth data, biologists can gain valuable insights into key fish population demographics, including age structure, growth rates, and recruitment dynamics. Much of WGFD current sampling efforts and annual to semi-annual surveys focus on collecting population estimates, CPUE of key species, and individual fish length and weight. While this can provide an indication of the status and trends of fish populations and communities within a waterbody, it provides limited information on the mechanisms driving observed trends and the most appropriate management actions to achieve desired outcomes. This project is a collaboration between the UWYO Fetzer Lab and the Wyoming Game and Fish Department. Otoliths provided by Wyoming Game and Fish Department staff will be mounted in an epoxy resin, sectioned using a low-speed, precision saw, and imaged using a dissection microscope equipped with a high-resolution camera. On each image, annuli will be identified, counted, and measured using ImageJ software and the statistical package RFishBC in R will be used to quantify back-calculated length-at-age.