• Login
    View Item 
    •   Home
    • University of Alaska Fairbanks
    • UAF Graduate School
    • Fisheries
    • View Item
    •   Home
    • University of Alaska Fairbanks
    • UAF Graduate School
    • Fisheries
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of Scholarworks@UACommunitiesPublication DateAuthorsTitlesSubjectsTypeThis CollectionPublication DateAuthorsTitlesSubjectsType

    My Account

    Login

    First Time Submitters, Register Here

    Register

    Statistics

    Display statistics

    Environmental drivers of fish communities and food webs in Gulf of Alaska estuaries

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    Lundstrom_uaf_0006N_11162.pdf
    Size:
    3.290Mb
    Format:
    PDF
    Download
    Author
    Lundstrom, Nina
    Chair
    Beaudreau, Anne
    Committee
    Mueter, Franz
    Konar, Brenda
    Keyword
    Fish communities
    Ecology
    Gulf of Alaska
    Habitat
    Estuarine fishes
    Food chains
    Metadata
    Show full item record
    URI
    http://hdl.handle.net/11122/12559
    Abstract
    The coastal Gulf of Alaska (GOA) is experiencing rapid, climate-driven ecological change. Climate forecasts predict increased temperatures and more precipitation as rainfall, but these changes will not have uniform effects across nearshore ecosystems. Estuarine habitats will be dynamically affected by changes in neighboring watersheds as glaciers melt and recede. Because estuaries provide critical habitat for many fishes, including some that support fisheries, it is important to understand how changing estuarine conditions may impact nearshore fish communities. The overall goal of this thesis was to investigate how environmental conditions, fish communities, and food webs vary across estuaries fed by watersheds with varying glacial coverage (0-60%). We conducted monthly beach seining and measured environmental conditions from April to September 2019 at ten estuary sites in two regions of the GOA, Lynn Canal in southeastern Alaska and Kachemak Bay in southcentral Alaska. The goal of Chapter One was to characterize differences in estuarine fish communities along the glacial gradient, between regions, and throughout the sampling season. We then focused on two abundant species in Lynn Canal, starry flounder (Platichthys stellatus) and Pacific staghorn sculpin (Leptocottus armatus), and used multiple years of data (2014, 2016-2017, 2019) to determine environmental drivers of size structure for each species. Fish communities showed the greatest differences between regions and across months, and temperature and salinity were significant drivers of variation in species composition. Variation in mean length of Pacific staghorn sculpin was best explained by year and the interaction of site and month, whereas variation in mean length of starry flounder was best explained by temperature, salinity, and turbidity. The goal of Chapter Two was to provide foundational information on the diet of juvenile coho salmon (Oncorhynchus kisutch) during the estuarine life stage and characterize variation in diets between years and regions. Juvenile coho salmon have a diverse diet of terrestrial and marine invertebrates and fishes, and they exhibited a shift to piscivory during this transitional period in nearshore habitats. Site differences accounted for most of the variability in diet, while temperature and salinity only accounted for a total of 12% of the variability in diet. Overall, we found that fish communities in GOA estuaries vary with environmental and habitat conditions, but that the glacial to non-glacial watershed gradient was less important in explaining variation in fish community structure than regional and interannual differences.
    Description
    Thesis (M.S.) University of Alaska Fairbanks, 2021
    Table of Contents
    General introduction -- Chapter 1: Environmental drivers of nearshore fish community composition and size structure in glacially influenced Gulf of Alaska estuaries -- Chapter 2: Juvenile coho salmon (Oncorhynchus kisutch) feeding ecology during the early period of marine entry in Gulf of Alaska estuaries -- General conclusion -- Appendix.
    Date
    2021-05
    Type
    Thesis
    Collections
    Fisheries

    entitlement

     
    ABOUT US|HELP|BROWSE|ADVANCED SEARCH

    The University of Alaska Fairbanks is an affirmative action/equal opportunity employer and educational institution and is a part of the University of Alaska system.

    ©UAF 2013 - 2023 | Questions? ua-scholarworks@alaska.edu | Last modified: September 25, 2019

    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.