Deep Secrets

Shedding light on deepsea ecosystems

Principal Investigator: Dr Kerry Sink (SANBI)

The Deep Secrets Project aims to build capacity so that we can research and understand our coast’s outer shelf, shelf edge and slope ecosystems and thereby support improved integrated ecosystem-based management across multiple sectors in South Africa. To achieve this, our research objectives focus on understanding the shelf edge geology and oceanography and how this influences benthic and pelagic biodiversity, biogeography, community structure and ecology. The research outputs support evidence-based decision making for the National Biodiversity Assessment, Marine Spatial Planning, Marine Protected Area design (including seven of the Phakisa proposed MPAs), ecosystem-based fisheries management, marine stewardship initiatives and marine sustainable development goals.

A key project component was a month long, offshore Phakisa cruise aboard R/V Algoa which involved 13 scientists, technical experts and students from nine organisations. Sampling 61 stations over more than 1500 km, the team examined 15 habitat types in South Africa’s National Marine Ecosystem Classification and Map.This included the first surveys of many deep-sea habitats. Sand, mud, gravel and rocky ecosystems were sampled and characterised. Additional work was done at key features which included an undocumented rocky ridge off Port Elizabeth, submarine canyons in the Amathole area and coral habitats at Browns Bank on the west coast and between Port Elizabeth and Knysna. Research highlights included the first survey of deep cold water coral habitats in South Africa, collection of cold water coral samples for taxonomic and genetic research and the deepest biodiversity survey to date at 1035 m off Knysna.