Fish Habitat and Otolith Chemistry

download Fish Habitat and Otolith Chemistry

of 17

  • date post

    02-Jan-2016
  • Category

    Documents

  • view

    64
  • download

    0

Embed Size (px)

description

Fish Habitat and Otolith Chemistry. By Nate Bickford and Brenda Norcross. Otolith Introduction. The location and identification of essential fish habitat has become a major focus of fisheries management. Traditional assessments of habitat use have relied on mark and recapture techniques. - PowerPoint PPT Presentation

Transcript of Fish Habitat and Otolith Chemistry

  • Fish Habitat and Otolith ChemistryBy Nate Bickford and Brenda Norcross

  • Otolith IntroductionThe location and identification of essential fish habitat has become a major focus of fisheries management.

    Traditional assessments of habitat use have relied on mark and recapture techniques.

    Recently fisheries managers have used otolith chemistry to identify fish movement and habitat.

  • Fish in ChukchiFish were collected during the Russian American Long Term Census of the Arctic (RUSALCA) Cruise

    Bering Flounder (Hippoglossoides robustus) BF is one of the most abundant flatfish in the Chukchi Sea.

  • MethodsFish were collected from 7 sites in the Chukchi Sea. Otolith were removed and thin sectioned in a clean environment.Chemical analyses were done by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS; otoliths; LSX-500). We are looking for elemental differences between core (natal) and edge (where they were collected).Elemental ratio we are concerned with are Sr/Ca Sr87/Sr86, Ba/Ca, and Mg/Ca.

  • Bering Flounder were collected at sites

    13, 15, 18, 20, 23, 25, and 58

  • Using a Quadratic Discriminant Analysis (QDA) different sites were grouped as water masses

    Then I used the QDA to predict the membership in each water mass

    Water MassWater Mass 1 Station 13, 15, 18, & 20Water Mass 2 Station 23, 25 & 58

    Water Mass 1 Station 13, 15, 18, & 2075%25%Water Mass 2 Station 23, 25 & 5828%72%

  • Location/ Water MassWater Mass 1 Station 13, 15, 18, & 20 Water Mass 2 Station 23, 25 & 58

    Station 1362%38%Station 1553%47%Station 1817%83%Station 208%92%Station 230%100%Station 2530%70%Station 5885%15%

    Total fish45102Percent of spawn in each water mass30%70%

  • There are multiple stocks of Bering flounder in the Chukchi Sea. Water mass 2 is essential for Bering Flounder in the Chukchi Sea

    Why is the habitat in water mass 2 better

  • Preliminary data Gymnocanthus tricuspis, Arctic staghorn sculpin

    Also collected during the RUSULCA cruise

  • Arctic Staghorn Sculpinwere collected at sites

    6, 11,13, 15, 17,18,20, 23, 25, 27, 58 62, 73, 85, 106, and 107

  • Artic staghornPossible multiple groupings in three to four water masses

    Next Step discriminant statistics

  • AcknowledgmentsSonja BickfordRobyn HanniganBrenda NorcrossChris StarkBrenda HollidayMatt KeyseFisheries Otolith Group (FOG)Tom WeingartnerSeth Danielson

    Funding National Science Foundation