rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    title: Species Composition, Relative Abundance, and Environmental Effects on Demersal Fishes in the Northwestern Gulf of Mexico
  name:
    name part: Johnson, Erin Meghan
    role:
      role term: creator
    role:
      role term: author.
  name:
    name part: Wells, R.J. David
    role:
      role term: thesis advisor.
  name:
    name part: Texas A&M University
    role:
      role term: degree granting institution.
  type of resource: text
  genre: bibliography
  origin info:
    place:
      place term: txu
    date issued: 2023
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: remote
    extent: 1 online resource.
  abstract: Species composition and abundance are important metrics to identify when addressing community structure and ecosystem health due to variable environmental factors. Data collected from the Texas Parks and Wildlife Department bottom longline survey was used to examine species composition, relative abundance and environmental effects on demersal fishes caught along the continental shelf of the northwestern Gulf of Mexico. Surveys from 195 locations in the northwestern Gulf of Mexico also included environmental data: salinity, temperature, dissolved oxygen, and depth. Generalized additive models were used to assess trends in richness, diversity, evenness, and relative abundance; and generalized linear models with binomial distributions were used to assess significant effects of collected environmental data on predicted presence probabilities of dominant species from the survey. A total of 2,802 individuals were caught during the survey consisting of 56% elasmobranchs and 44% bony fishes. Species richness, diversity and relative abundance were mainly affected by region, year, and depth. Six species accounted for 93% of the total catch including blacktip sharks Carcharhinus limbatus, Atlantic sharpnose sharks Rhizoprionodon terraenovae, gafftopsail catfish Bagre marinus, red drum Sciaenops ocellatus, spinner sharks Carcharhinus brevipinna, and bull sharks Carcharhinus leucas. Region and the interaction between temperature and dissolved oxygen were the most common significant effects on species presence. Results from this study provide baseline data for demersal fishes in the northwestern Gulf of Mexico, allowing for future evaluations in changes of the species composition and abundance over time. The electronic version of this dissertation is accessible from https://hdl.handle.net/1969.1/198046
  note: by Erin Johnson.
  note: "Major Subject: Marine Biology"
  note: Includes vita.
  note: Master of Science Texas A&M University 2022 https://hdl.handle.net/1969.1/198046
  note: Includes bibliographical references.
  note: Text (Thesis)
  subject:
    topic: Major Marine Biology
  subject:
    topic: demersal fishes
  subject:
    topic: northwestern Gulf of Mexico
  subject:
    topic: bottom longline
  subject:
    topic: environmental effects
  subject:
    topic: species composition
  subject:
    topic: abundance
  subject:
    topic: relative abundance
  subject:
    topic: Gulf of Mexico
  subject:
    topic: environmental factors
  subject:
    topic: Texas gulf
  subject:
    topic: Texas coast
  subject:
    topic: blacktip shark
  subject:
    topic: Atlantic sharpness shark
  subject:
    topic: gafftopsail catfish
  subject:
    topic: red drum
  subject:
    topic: spinner shark
  subject:
    topic: bull shark
  subject:
    topic: monitoring program
  subject:
    topic: long-term monitoring
  subject:
    topic: longline survey
  identifier: https://hdl.handle.net/1969.1/198046
  record info:
    record content source: TXA
    record creation date: 240827
    record change date: 20240829173512.8
    record identifier: in00005468545
    language of cataloging:
      language term: eng