UKZN Student Explores Continental Shelf Ecosystems

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How marine sediments contribute to the ecology of the Natal Bight continental shelf was the subject of a thesis by Ms Candice Untiedt of the School of Life Sciences who completed her Biology Masters degree through UKZN.

Her study formed part of the larger African Coelacanth Ecosystem Programme (ACEP II) Natal Bight Project. 

Untiedt, who did her undergraduate and Honours degrees at UKZN, chose to continue with her Masters study at the University because of its affiliation with world-class research institutes such as the Oceanographic Research Institute (ORI), where she was based for the duration of her masters. Her work was supervised by Ms Fiona MacKay. 

‘Untiedt’s masters formed a wonderful study, said MacKay. ‘She looked at the ecosystem and functional attributes of small animals living in marine sediments - work which contributed greatly to the multi-institutional, multi-disciplinary ACEP II project.’ 

Said Untiedt: ‘I was very fortunate to have Dr Fiona MacKay as my supervisor and mentor during my masters degree. She disseminated years of knowledge to me and I have learnt a great deal from her, not only in terms of this field but also in terms of being a professional. I feel incredibly lucky to have studied under such a renowned macrobenthic ecologist who works ethically with integrity and passion. 

Untiedt pursued the field of Biology because she wanted to make a difference in the world and contribute to something greater than herself. I’m constantly amazed and inspired by the beauty and intricate design of the natural world and feel that through understanding it we better understand ourselves.’  

Untiedt’s research involved the challenging task of sorting, identifying, counting and weighing of the enormously diverse macrobenthic samples she collected along the unique, highly diverse Natal Bight shelf habitat off Richard’s Bay, Durban and the Thukela River mouth during two cruises. 

The ecosystem of the shelf is influenced by local oceanographic features and out-welling via one of the largest rivers in the country. 

Untiedt found that the Thukela feature area supported the most abundant and nutrient-rich macrobenthic community, suggesting that Thukela River outflow has a significant effect on the functioning of the Natal Bight ecosystem.  

The benthic fauna studied by Untiedt are important for their contribution to the productivity and functioning of the central shelf as they provide food for human populations and are prey for commercially important, bottom-feeding fauna. The identification of the effect of the Thukela River outflow on the functioning of the adjacent shelf also has implications for the management of the river mouth, especially given that commercial fishery operates on the inner shelf of the central Natal Bight. Untiedt explained that the abundance of fishing stocks increases during periods of high river flow and decreases during low outflow.  

Untiedt’s study is important given the fact that most studies on macrobenthos previously undertaken in South African waters have concentrated mainly on the country’s west coast, making Untiedt’s work important in filling in the knowledge gap in terms of the benthic biodiversity on the subtropical east coast.  

Her work also yielded many new, possibly undescribed taxa and new distribution information. 

Untiedt hopes that the research she has produced will play a part in highlighting the importance of marine research on the east coast of South Africa and she plans to continue her studies specialising in macrobenthic taxonomy and the development of taxonomic tools for ecologists. 

-          Christine Cuénod