A vast number of species in the world’s oceans remain unknown to science, and Norway’s research vessel Dr Fridtjof Nansen has helped uncover dozens of them through expeditions in poorly studied waters, according to the Institute of Marine Research.
Scientists working aboard the vessel have, over the past few decades, identified and formally described 90 previously unknown species.
Many were identified during surveys in parts of the Global South where little or no scientific data previously existed. The finds range from fish and sharks to molluscs, crustaceans, sea cucumbers, and jellyfish.
Research where few have looked before
Dr Fridtjof Nansen operates in waters rarely surveyed by scientists. The ship is part of the EAF-Nansen Programme, a long-running partnership among Norway, the UN Food and Agriculture Organisation (FAO), and Norad. Its main aim is to help developing countries build ecosystem-based fisheries management systems and improve food security.
On board, researchers collect a wide range of data. They measure temperature, salinity, oxygen and acidity. They also sample plankton, fish larvae, pollution and plastics.
Each catch is examined closely to identify the species. According to the Institute, surveys in these regions often reveal numerous species but few individuals of each, unlike in better-known areas such as the Barents Sea.
Kathrine Michalsen, a marine scientist and cruise coordinator on the vessel, notes that the lack of earlier data explains why unknown species continue to appear. When science enters new waters, new life often follows.
A slow and careful detective job
Finding a possible new species is only the start. Identification can take years. Scientists must rule out that the organism is a known species with unusual traits or one found outside its usual range. Experts compare body shape, fins, teeth, colour and measurements. DNA tests and X-rays may follow.
Marine biologist Sarah Bruck, who has participated in numerous Nansen cruises, describes the work as detective-like. Some catches can contain up to 100 different species, including bottom-dwelling animals. Often, only one specimen of a potential new species is available, which slows the process.
If scientists on board cannot identify an organism, the case is passed on to FAO taxonomists and external experts. Images, samples and data are shared worldwide. In some cases, more than 5 years pass between the first capture and the official naming.
From deep seas to dangerous jellyfish
The programme’s discoveries include striking examples. Surveys off Mozambique led to the description of eight new species, including a goatfish later named Parupeneus nansen after the vessel. Work in the Indian Ocean produced guides listing dozens of species, many of which were new to science.
Not all finds are harmless. Expeditions off southern Africa uncovered several new jellyfish species, including box jellyfish related to some of the most venomous animals known. These were found far from the regions where such species had previously been recorded.
In total, researchers involved in the programme have collected more than 2,000 different taxa. Only 90 have so far been confirmed as new species, but many more await study.
Scientists report that the deep sea remains one of the least explored parts of the planet and likely harbours many more unknown forms of life.
