Department of Ichthyology and Fisheries Science; Rhodes University

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  • Department of Ichthyology and Fisheries Science; Rhodes University

  • Department of Ichthyology and Fisheries Science; Rhodes University

    Southern African Artemia populations

    Horst Kaiser and Tom HechtDepartment of Ichthyology and Fisheries

    Science (DIFS), Rhodes University, South Africa

    Collaborators (AUTH)

    Theodore J. AbatzopoulosAthanasios BraxevanisIlias KappasAlexander Triantafyllidis

    DIFS

    Tom HechtGuy PauletAndrew GordonSaltworks managers

  • Department of Ichthyology and Fisheries Science; Rhodes University

    Background to this study

    No in-depth studies of African Artemia were available at the beginning of the study.

    The species-richness of southern African Artemia populations has not been described.

    South Africa provides unique opportunities for sampling.

  • Department of Ichthyology and Fisheries Science; Rhodes University

    Study approach1. Sample new southern African populations

    (2001/2).2. Training: genetic analysis of first samples at

    AUTH (2002).3. Conduct a comprehensive sampling trip in

    South Africa / Namibia (2003).4. Study Artemia genetics at AUTH (2004).5. Future objectives: Continue sampling new

    sites and obtain funding for Artemia population studies (2004 - ongoing).

  • Department of Ichthyology and Fisheries Science; Rhodes University

    Findings and progress1. Sampling at three previously unstudied sites

    (2001/2) in the Eastern Cape, South Africa.2. Description of a mixed population at Coega

    (Eastern Cape) (2002).3. Travelled to more than 33 sites and obtained

    records from 45 sites in southern Africa. Collected material from14 populations (2003).

    4. Ongoing: Genetic analysis of the recently collected populations at AUTH (publications pending).

  • Department of Ichthyology and Fisheries Science; Rhodes University

    Study areas

    Site characteristics Temperature data (mean, min./max.) Reproductive mode in 9 Artemia

    populations from which adults were collected.

  • Department of Ichthyology and Fisheries Science; Rhodes University

    Frequency distribution of 45 southern African Artemia sites according to elevation (m above sea level)

    0 200 400 600 800 1000 1200 1400 1600Elevation (m)

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  • Department of Ichthyology and Fisheries Science; Rhodes University

    Frequency distribution of 45 southern African Artemia sites according to average ambient temperature (C)

    14 16 18 20 22 24 26Average annual temperature C

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  • Department of Ichthyology and Fisheries Science; Rhodes University

    Frequency distribution of 45 southern African Artemia sites according to maximum temperature (C)

    30 32 34 36 38 40 42Maximum temperature (C)

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  • Department of Ichthyology and Fisheries Science; Rhodes University

    Frequency distribution of 45 southern African Artemia sites according to minimum temperature (C)

    -10 -8 -6 -4 -2 0 2 4Minimum temperature (C)

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    10121416182022

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  • Department of Ichthyology and Fisheries Science; Rhodes University

    Brandvlei (10/47)

    Yzerfontein (13/33)

    Missionvale (3/10)

    SwartkopsMarina (9/5)

    SwartkopsCerebos(7/7)

    Reynekespan (30/17)

    South African sites

    Males Females/

  • Department of Ichthyology and Fisheries Science; Rhodes University

    Swakopmund (0/30)

    Walvis Bay (0/42)

    Henties Bay (14/5)

    Namibian sites

    Males Females/

  • Department of Ichthyology and Fisheries Science; Rhodes University

    Main findings

    A mixed population of Artemia found at Coega in the Eastern Cape, South Africa.

    Several bisexual populations across South Africa.

    One bisexual and one parthenogenetic population in addition to one known parthenogenetic strain in Namibia.

    An update of existing reviews of African Artemialocations and species (database).

  • Department of Ichthyology and Fisheries Science; Rhodes University

    Where should we go from here? Identify a site for a a long-term study of population

    changes (Example: The Sundays River or SwartkopsPan in the Eastern Cape).

    Identify and study sites in southern Africa into which Artemia may have been introduced (Potential example: some commercial sites).

    Joint fund-raising and close collaboration with Artemia research institutions.

    continued

  • Department of Ichthyology and Fisheries Science; Rhodes University

    Contd

    Establish a network of African researchers (ongoing) Ornithologists, geologists, ecologists

    Establish better contacts with saltworks operators: Requires attention to conflicting interests!

  • Department of Ichthyology and Fisheries Science; Rhodes University

    Acknowledgments EU-Commission for providing the funding. The AUTH team for their help throughout the

    study and many fruitful discussions. The ARC team for advice and project

    administration. The DIFS team for their help with sampling

    and for patiently sharing my excitement about Artemia.

    The Greek football team for writing history while I was there to watch

    Southern African Artemia populationsBackground to this studyStudy approachFindings and progressStudy areasFrequency distribution of 45 southern African Artemia sites according to elevation (m above sea level)Main findingsWhere should we go from here?ContdAcknowledgments