SINGAPORE: On Feb 14, a team of nine researchers from the National University of Singapore (NUS) embarked on an expedition to explore an understudied area in the world's largest ocean.
Five weeks later, they returned with hundreds of deep-sea creatures, some of them possibly new to science.
The creatures were pulled from the depths of the Pacific Ocean, thousands of metres below the surface, in an understudied area known as the Clarion-Clipperton Zone (CCZ).
The expedition, led by Keppel's Corporation subsidiary, Ocean Mineral Singapore, is part of the research done by Keppel-NUS Corporate Laboratory.
The expedition team aimed to conduct environmental studies and surveys for the collection of polymetallic nodule deposits in an environmentally friendly way.
Polymetallic nodules contain valuable metals such as cobalt, copper, nickel, manganese and other valuable ores. These are used in electronics and green technology, such as electric cars, wind turbines and solar panels.
UNIQUE DEEP-SEA HABITAT
Reaching down between depths of 4,000m to 6,000m below the surface, the CCZ is also often referred to as an abyssal plain.
The creatures that live on the seafloor of the CCZ mostly feed from food that falls from above and are often very small, measuring less than 2cm.
Box corers were used in taking samples from the seabed. When a piece of the seabed was brought up from the seafloor, the team would take samples of the sediment to study the microbes, foraminiferans, meiofauna, macrofauna and megafauna.
"The vast seafloor of the CCZ ... comprises a unique deep-sea habitat that is little known," said NUS Tropical Marine Science Institute (TMSI) senior research fellow Dr Tan Koh Siang.
"More work needs to be done to understand the impact of nodule collection on the biological community and how we can conserve and protect it for future generations."
The team hopes by determining the identities and distribution of the species in the seafloor, it would help further understand the biology and ecology of the zone.
"The knowledge gained will help in managing the nodule collection activities without undue detriment to the ecosystem," NUS said.
At the moment, the plan is to sort, identify and count the samples the collected collected.
"This is an involved process as most of the organisms are less than 2mm in size," Dr Tan said.
He added if new species are discovered, they will need to be formally described and published.
"BAMBOO WORMS" AND DEEP-SEA SPONGES
Here are some of the creatures discovered by the team, in photos.
Three species were discovered, potentially new to science.
They include a deep-sea sponge, some isopod crustaceans, as well as a unique type of single celled organisms with nuclei called Foraminifera - with a skeleton made up of numerous glass-like needles woven together.
Belonging to the family Polymastiidae, this deep-sea sponge is distinguished by its reduced or simplified skeleton, possibly due to the limited food available in the depths of the zone.
Related to crabs and shrimps, these isopods are quite common in the zone. While most of these are small, some can grow up to half a metre in length in deeper waters.
This specimen is from a group of organisms called Foraminifera, which are single-celled organisms with nuclei known as protists.
Unlike other Foraminifera, this specimen’s skeleton is made up of numerous glass-like needles woven together, which appear to be unique among the diverse creatures in the zone.
Other creatures included an unusually long deep-sea worm, a variety of copepod crustaceans as well as mollusc.
This "unusually long" deep-sea worm belongs to the family Maldanidae. Members of this family are often referred to as "bamboo worms", due to the resemblance to bamboo stems.
Measuring 10cm, this worm is one of the largest polychaete worms seen to date from the CCZ.
Belonging to a large group known as the Harpacticoida, these deep-sea copepods live on or in the sediment of the seafloor.
Commonly found in oceans around the world, these tiny crustaceans come in a variety of body shapes. Many of these could be new to science.
A mollusc with an umbrella-shaped shell like that of a limpet - specimens like these were thought to be extinct for years until living specimens were found in the 1950s.