department of ichthyology and fisheries science; rhodes university
TRANSCRIPT
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
Cont’d
• 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 …