Funding for this research was provided by:
Austrian Science Fund (P 27605-B25)
Text and Data Mining valid from 2019-01-31
Received: 27 August 2018
Accepted: 20 December 2018
First Online: 31 January 2019
Ethics approval and consent to participate
: Field work was carried out with the permission of the Fisheries Department of Zambia and under a study permit issued by the government of Zambia (SP 007216).
: Not applicable.
: The authors declare that they have no competing interests.
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