Juvenile Chinook salmon early ecology, prey and condition on the Yukon Delta, AK

Salmonid Research, Monitoring, and Evaluation (RM&E)

Project ID1511
Recovery Domains -
Start Date07/31/2015
End Date06/30/2018
Last Edited07/28/2021
1 - 1


Juvenile Chinook salmon on the Yukon River undertake one of the longest fish migrations in the world, travelling over 3000 kilometers from spawning grounds in Canada to the marine waters of the Bering Sea. Evidence suggests that much of the variability in Yukon River Chinook salmon production occurs prior to the end of the first summer at sea, either during freshwater rearing, downstream migration, or entry into the marine environment. Prey availability and prey quality are important factors in juvenile Chinook salmon growth and condition. This research investigated spatial and temporal patterns in prey consumption and availability on the Yukon River Delta. Results suggest that while there are limited spatial differences in availability, prey varies seasonally and juvenile Chinook exhibit prey selectivity. Comparisons of the results of this study with data from prior sampling years indicates that juvenile Chinook salmon in 2016 had lower stomach fullness and lower energy density than Chinook from prior years. Additional years of prey sampling is needed to identify factors that affect prey availability.

Project Benefit    

The general patterns investigated in this research provide insight into factors that may affect juvenile Chinook salmon growth and condition prior to their first marine summer. However, additional tools are needed to tease out factors contributing to variation in diets and energetic content. This survey samples several migrating populations of Chinook, some of which have travelled up to 3,000 km and some that originated from tributaries in the Lower Yukon. It is reasonable to expect that there may be differences in growth and condition based on distance traveled and habitats encountered. New tools, such as advanced genomic methods or otolith chemistry, need to be evaluated for their potential to identify groups or clusters within the outmigration that can provide insight into factors affecting juvenile Chinook salmon health.


Metric Completed Originally

Funding Details

In-Kind Donated Labor$31,823
Report Total:$526,033

Project Map



  • Worksite Identifier: 37257124
  • Start Date: 07/31/2015
  • End Date: 02/08/2016
Area Description
Yukon River Delta

Location Information

  • Basin: Lower Yukon
  • Subbasin:
  • Watershed:
  • Subwatershed:
  • State: Alaska
  • Recovery Domain:
  • Latitude: 62.77624449006963
  • Longitude: -164.52484130858085


  • Un-Named ESU Chinook




  • E.0 Salmonid Research, Monitoring, and Evaluation (RM&E)Y (Y/N)
    •      . . E.0.a RM&E Funding 526,118.00
    •      . . E.0.b
      Complement habitat restoration project
    •      . . E.0.c
      Project identified in a plan or watershed assessment.
      Schindler, D., Krueger, Bisson, Bradford, Clark, Conitz, Howard, Jones, Murphy, Myers, Scheuerell, Volk, Winton. Arctic-Yukon-Kuskokwim Chinook Salmon Research Action Plan: Evidence of Decline of Chinook Salmon, AYK SSI, Aug 2013
    •      . . E.0.d.1 Number of Cooperating Organizations 4
    •      . . E.0.d.2
      Name Of Cooperating Organizations.
      Alaska Fisheries Science Center, Yukon Delta Fisheries Development Assoc., Spearfish Research, University of Alaska Anchorage
    •      . . E.0.e.1 Number of reports prepared 1
    •      . . E.0.e.2
      Name Of Report
      Draft final report: JUVENILE CHINOOK SALMON (ONCORHYNCHUS TSHAWYTSCHA) EARLY ECOLOGY, PREY AND CONDITION ON THE YUKON DELTA, ALASKA, Katharine Miller, Alaska Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration
    •      . . E.2 ResearchY (Y/N)
      •      . . . . E.2.a Research Funding 526,118.00
      •      . . . . E.2.b.4 Life history studyY (Y/N)
        •      . . . . . . E.2.b.4.a
          Key issues addressed by life history research
          The project collected data to characterize habitat usage, size, diet, marine entry timing, and condition of juvenile Chinook salmon in the Yukon River Delta by combining net sampling methods in the three main tributaries of the Yukon River and offshore delta front/prodelta locations.