department of ichthyology and fisheries science; rhodes university

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Department of Ichthyology and Fisheries Science; Rhodes University

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Page 1: Department of Ichthyology and Fisheries Science; Rhodes University

Department of Ichthyology and Fisheries Science; Rhodes University

Page 2: 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

Page 3: Department of Ichthyology and Fisheries Science; Rhodes University

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.

Page 4: Department of Ichthyology and Fisheries Science; Rhodes University

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).

Page 5: Department of Ichthyology and Fisheries Science; Rhodes University

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).

Page 6: Department of Ichthyology and Fisheries Science; Rhodes University

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.

Page 7: Department of Ichthyology and Fisheries Science; Rhodes University

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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Page 8: Department of Ichthyology and Fisheries Science; Rhodes University

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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Page 9: Department of Ichthyology and Fisheries Science; Rhodes University

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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Page 10: Department of Ichthyology and Fisheries Science; Rhodes University

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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Page 11: Department of Ichthyology and Fisheries Science; Rhodes University

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/

Page 12: Department of Ichthyology and Fisheries Science; Rhodes University

Department of Ichthyology and Fisheries Science; Rhodes University

Swakopmund (0/30)

Walvis Bay (0/42)

Henties Bay (14/5)

Namibian sites

Males Females/

Page 13: Department of Ichthyology and Fisheries Science; Rhodes University

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).

Page 14: Department of Ichthyology and Fisheries Science; Rhodes University

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 …

Page 15: Department of Ichthyology and Fisheries Science; Rhodes University

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!

Page 16: Department of Ichthyology and Fisheries Science; Rhodes University

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 …