Cape Town - The team of young marine scientists, which departed in February on a two-week multi-institutional and multidisciplinary offshore ocean expedition to uncover secrets that lie far beneath the sea surface, have shared a glimpse of what they found in the depths of South Africa’s oceans.
The aim of this voyage was to facilitate a greater understanding of South Africa’s oceans and approach the management of them more holistically and more representatively.
The expedition was facilitated by the South African Institute for Aquatic Biodiversity (NRF-Saiab), a national facility of the National Research Foundation, and funded by One Ocean Hub.
Young marine biologist Luther Adams from the South African National Biodiversity Institute (Sanbi) led the team of young researchers in the One Ocean Hub Capacity Development Research Cruise from the port of East London. Adams said the expedition allowed him to use modern technology and new techniques to uncover secrets far beneath the surface of South Africa’s oceans.
Using deep-sea landers technology, the team explored depths up to 1 000 meters and came across a dumbo octopus, a variety of deep-water shark, grenadiers with rippling tails and enormous eyes, as well as cut-throat eels with prehistoric jaws and serpentine bodies, among numerous others.
Deep-sea landers are remote underwater video stations that are baited to allow scientists to record fish, sharks and other deep-sea creatures attracted to the bait.
The scientists also made use of technology, including an ROV (remotely operated vehicle), which captured video and images, and collected biological samples using a manipulator arm and other oceanographic instruments to explore deep-sea habitats in underwater caves and canyons never before seen.
Anthony Bernard, instrument scientist at Saiab, was driving the development of the landers.
“Deep-sea landers are opening new avenues for offshore research and are providing the first images of slope ecosystems. This passive, non-invasive method of surveying will help to better inform the management of deep-sea and benthic (lowest level of a body of water) habitats,” Bernard said.
Bernard explained that this technology allowed them to collect information about slope habitats, where activities like petroleum exploration and mining may occur.
The team has been surveying at three depths: 300, 600, and 900 metres, to compare life at different ocean depths.
Professor Kerry Sink, manager of the marine programme at Sanbi, said: “The first deployment to 300m yielded a fish of impressive size, known as a hapuku wreckfish. Some of the other interesting characters that arrived included bright red rockfish (Jacopevers), spindly and long-legged stone crabs, grenadiers with rippling tails and enormous eyes, and cut-throat eels sporting prehistoric jaws and serpentine bodies.
“Numerous species of deep-water sharks were observed, including the arrowhead dogfish and balloon catsharks, both of which are near-threatened.
“To the collective delight of the team, a dumbo octopus was captured swimming by using its ear-like fins positioned on its head. This was the highlight of the deepest deployment at a depth of 1035m,” Sink said.