SAIAB News » Review of the hunt for ‘dinosaurs’ in Sodwana Bay’s underwater canyons

Review of the hunt for ‘dinosaurs’ in Sodwana Bay’s underwater canyons

11 October 2018

By: Lucky Dlamini – DST/NRF-SAIAB Communications Intern

Coelacanth at 114m in Jesser Canyon in the iSimangaliso Wetland Park off Sodwana Bay.
This individual was first sighted 
in 2005 (pic by DST/NRF/ACEP Canyon Connections Project)

An expedition by marine scientists and film-makers to find the rare and primitive fish species, the coelacanth, in Sodwana Bay set off in June this year drawing a great deal of national media attention to this 400-million-year-old amazing fossil fish. ROV pilot and Technical Coordinator of the African Coelacanth Ecosystem Programme (@ACEP_ZA) which is managed by the South African Institute for Aquatic Biodiversity (@NRF_SAIAB), Ryan Palmer, gave an overview on the nitty-gritty of this cruise.

“The search for South Africa’s rare dinosaur fish was part of one of the Open Call projects which was awarded competitively. Typically, for the Open Call projects, ACEP provides technical and logistic support in terms of supplying a submersible remote operating vehicle (ROV), baited remote underwater videos (BRUV) and other marine platforms, as well as funding towards running costs and bursaries,” said Palmer.

The project which is led by Dr Mandy Lombard (Nelson Mandela University) and Dr Jean Harris (WILDOCEANS) is supported by both WILDOCEANS who provided the Research Vessel Angra Pequena, and ACEP who provided funding, technical and logistical support. Palmer said:  “Part of this partnership was to leverage funding for the research cruise.”  Palmer further explained that the importance of collaborating with film-makers was to ensure that the research is put out into the public realm: “Often research gets used for publication but does not get broadcast to the public. As researchers it is important for us to let people see what we are doing.”

Palmer clarified that the project was not exclusively focused on the coelacanths. “It was a study of the canyons which are the habitat of the coelacanths in Sodwana Bay. Comparing the biodiversity in and around the canyons to that away from the canyons is a way of studying the importance of these canyons.” According to Palmer, this research adds new information to what is already known not only about coelacanths but their environment.

A vast and dense bed of sea pens around the head of Diepgat Canyon in the iSimangaliso Wetland Park,
South of Sodwana Bay provides a habitat for marine animals. This may indicate a highly productive,
rich environment associated with the canyons (pic by DST/NRF/ACEP Canyon Connections Project
)

Today's technologies allow researchers to explore the ocean in increasingly systematic, scientific and non-invasive ways. With continuing scientific and technological innovations, scientists’ abilities to observe the ocean environment and its resident creatures is becoming advanced and technologies assist in expanding  understanding and appreciation of rarely explored realms.

Palmer confirms that the expedition was successful although the sea conditions were challenging. “We hoped to get more time with the ROV at the bottom, but the strong current did not allow this; however, that’s the nature of this unpredictable coastal environment,” said Palmer. Nonetheless, the team still managed to get the ROV dives and collected an encouraging amount of BRUV, oceanographic and biological data in and around the canyons.

Benthic ctenophores are a type of comb jelly fish that anchor themselves to animals on the
bottom rather than swimming freely in the water column (pic by DST/NRF/ACEP Canyon Connections Project.)

Highlighting some of the technologies that make exploration possible today and the scientific achievements that result from exploration, Palmer explained that they received great capacity in research output from the research because of the adoption of technology and innovative equipment like the ROV, the BRUV and the CTD Rosette System. “Until we got the ROV, most of the visual work that has been done in the marine environment has been down to 30 meters because that’s the limit for diving for regular scuba divers. There have been some divers that have gone deeper up to 100/110-20 meters but this is risky and very technical and you only have very little bottom time. The ROV allows us to work down to the depths of about 300 meters. For the first time, it allows researchers to that environment for visual work.”

As for the BRUV, Palmer explained that it allowed for them to conduct quantitative fish research of up to 100-120 meters. “It is quite a new thing just to be able to get down there and count fish and measure them,” said Palmer. Another technological equipment that was used was a CTD Rosette, an oceanography instrument for measuring conductivity, temperature, depth and chlorophyll particles in the water column. “The CTD has a number of senses on it that take a reading up to four times a second, providing a profile of physical properties through the work column” said Palmer. The advantage of CTD casts is the acquisition of high resolution data.

The Seaeye Falcon ROV allows researchers to explore
and conduct 
research down to 300m (pic by Ryan Palmer)

It is these technologies that include platforms such as vessels and submersibles, observing systems and sensors, communication technologies, and diving technologies that transport marine scientists across ocean waters and into the depths and allow them to scientifically examine, record and analyse the mysteries of the ocean.

The research team are in the planning process for an extension of this expedition in 2019, though without the filmmakers as they are planning to focus less on coelacanths. The team plans to perform extended benthic surveys in and around the canyons and the research outputs from the cruise will go towards marine spatial planning. Benthic surveys are an important tool in aquatic research and are one of the main ways that scientists assess the health of coastal waters.

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The expedition would not have been possible without dedicated sponsors and organisations committing themselves to investing in scientific research. ACEP receives its funding from the Department of Science and Technology (DST) through the National Research Foundation (NRF). WILDOCEANS also contributed funding as it was a joint expedition and iSimangaliso Wetland Park provided the researchers with access to the canyons where the research will continue to be conducted. A special mention of the Principle Investigators for the project, Dr Mandy Lombard who is based at Nelson Mandela University and Dr Jean Harris from WILDOCEANS.