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National Center for Ecological Analysis and Synthesis

Project Description

Decreases in the body size and age of returning adult salmon have been noted for several Alaskan salmon species. Size and age declines have the potential to impact the biomass and stability of salmon populations. Despite evidence for decreased size and age of spawning adult salmon for some species and rivers, a comprehensive synthesis of size and age trends across species and populations is currently lacking. Several potential drivers of size and age shifts have been proposed, including fisheries, climate change, and density dependence at sea. However, the consistency of trait changes across populations and the contributions of the various potential drivers are unknown. Understanding the consistency and causes of age and size changes is important because these traits underlie many important aspects of ecological function and the value of salmon for human use. The aims of this working group are to examine the consistency, causes, and consequences of declining size and age in five species of Pacific salmon in Alaska. Specifically, we will ask: 1. Consistency: How consistent are changes in size and age across species, regions, and populations? 2. Causes: How are changes in size and age related to variation in potential drivers, including fisheries, climate change, and density dependence at sea? 3. Consequences: What are the consequences of age and size changes for the ecological, economic, and cultural value of salmon? We will synthesize existing data on Alaskan salmon size and age trends across species, regions, and populations to assess whether declines in size and age noted for some populations are widespread. We will examine the relationships between size and age changes and potential drivers, including fishing mortality, climate change, and density dependence. Finally, we will examine the consequences of size changes for ecosystems and human uses, including ecological implications for coastal, riverine, and interior ecosystems and the economic and cultural value of salmon for the people of Alaska. Our data synthesis will contribute basic insights into the causes and consequences of contemporary trait changes in wild populations and applied insights into how to successfully manage economically and culturally important biological resources in an era of rapid environmental change.

Principal Investigator(s)

Eric Palkovacs, Marissa L. Baskett, Stephanie M Carlson, Andrew P. Hendry, Bert Lewis, Peter Westley

Project Dates

Start: January 1, 2017

End: March 31, 2018

completed

Participants

Marissa L. Baskett
University of California, Davis
Stephanie M Carlson
University of California, Berkeley
S. Jeanette Clark
University of California, Santa Barbara
Jorge Cornejo-Donoso
University of California, Santa Barbara
Curry Cunningham
Alaska Department of Fish and Game
Frank W. Davis
University of California, Santa Barbara
Ian Dutton
Nautilus Impact Investing, LLC
Andrew P. Hendry
McGill University
Sarah Inman
University of Washington
Madeline Jovanovich
University of Alaska, Fairbanks
Vadim Karatayev
University of California, Davis
Neala Kendall
Washington Department of Fish and Wildlife
Jared Kibele
University of California, Santa Barbara
Holly Kindsvater
State University of New Jersey, Rutgers
Katie Kobayashi
University of California, Santa Cruz
Bert Lewis
Alaska Department of Fish and Game
Michael Malick
Simon Fraser University
Kaitlyn Manishin
University of Alaska, Fairbanks
Stephan B. Munch
NOAA, National Marine Fisheries Service (NMFS)
Krista Oke
McGill University
Eric Palkovacs
University of California, Santa Cruz
John D. Reynolds
Simon Fraser University
Katherine Schake
Nautilus Impact Investing, LLC
Michael Springborn
University of California, Davis
Gale Vick
Tanana Chiefs Conference
Sarah Warnock
Nautilus Impact Investing, LLC
Peter Westley
University of Alaska, Fairbanks

Products

  1. Journal Article / 2018

    Comprehensive evaluation of genetic population structure for anadromous river herring with single nucleotide polymorphism data