Singapore and Indonesia researchers uncover at least 12 new deep sea species off Java
But the new discoveries may just be the ‘tip of the iceberg’ with thousands of specimens collected
By Neo Chai Chin
Scientists from Singapore and Indonesia have found at least 12 species of hermit crabs, prawns, lobsters and crabs that are new to science in the deep sea off western and southern Java.
The South Java Deep Sea Biodiversity Expedition 2018 (SJADES 2018), the first such expedition jointly organised by both countries, also yielded more than 40 species that are new records for Indonesia.
The figures may be the tip of the iceberg as the researchers now go through the 12,000 specimens collected during the 14-day expedition, crab expert Professor Peter Ng told reporters on Tuesday (April 17).
Ng is the chief scientist for the Singapore team and head of the Lee Kong Chian Natural History Museum.
Thirty-one scientists and a 25-member support crew set off on the Indonesian research vessel, Baruna Jaya VIII, on March 23 from Jakarta. They sailed anti-clockwise towards Cilacap in southern Java and back, sampling at depths averaging 800 metres and up to 2,100m.
Among the new species are a crab with fuzzy spines and blood-red eyes, a lobster with long arms and a zebra-patterned shell, and a hermit crab with green eyes and orange banded pincers.
The largest creatures hauled up include a squid 40 centimetres to 50cm long, purple sea cucumbers weighing about 1 kilogram each and a tulip sponge about 1m long that anchors itself to the ground with glass threads. The smallest creatures include worms and a type of crustacean called copepods that are 1 millimetre to 2mm in size, or tinier.
The scientists faced stormy weather at the start due to the tail-end of a cyclone, and about half of them were sea-sick on the first day. But the terrain posed a far greater challenge. “Getting used to the seasickness was quite easy; getting used to the terrain was very difficult. Sampling was very difficult,” said Ng.
The depths and terrain given on maps were wrong, resulting in nets being ripped when they were sent down. Out of eight trawl nets which the team took along, seven were ripped and nights were spent repairing some of the nets.
Other equipment included dredges (which are made of steel), box corers and multi-corers to collect samples from mud and soil, as well as preservatives. The equipment weighed 4.5 tonnes, while fuel accounted for 98 tonnes of the vessel’s load.
The expedition proved valuable, especially for the younger scientists with little deep-sea experience.
Deep-sea expeditions have traditionally been organised by the French, Americans, Australians, and English. Ng said being tasked with the primary responsibility this time round was important. For instance, it was a “learning curve” each time the team threw down the multi-corer. “You know what to do in theory… but it’s not so easy, when the waves are 3m high, to know when it hits the bottom,” he said.
Some expedition members are also involved in studies of an area 80 times the size of Singapore in the Pacific Ocean. Ocean Mineral Singapore, a unit of Keppel Corporation, signed a 15-year contract with the International Seabed Authority in 2015 to explore how metal-rich rocks could be harvested and is working with the Keppel-National University of Singapore (NUS) Corporate Laboratory to conduct environmental studies and surveys for the metal deposits.
“(SJADES 2018) will be useful for our next trip in the Pacific. We’ve been there once and hope to do it again (next year),” said NUS Tropical Marine Science Institute’s Lim Swee Cheng, who studies sponges.
The scientists’ haul from the deep featured an unwelcome component: marine trash in the form of plastic bags, snack wrappers, coffee sachets, toothpaste tubes and even clothes.
Out of 63 stations where samples were collected, only five or six were without rubbish, said hermit crab expert and the Indonesian team’s chief scientist Dwi Listyo Rahayu.
“Yes, we found somebody’s underpants at (a depth of) 1,000m,” said Ng. “Deep-sea trash, we’re finding it almost everywhere on the planet, even in the most isolated places in the Pacific or Indian oceans where there are no human beings around… the problem with plastic is, it’s everybody’s problem, so it’s nobody’s problem.”
Marine trash can cause animals to get entangled and has been found in the gut of whales and other creatures.
The scientists will now study the specimens collected from the expedition, and hope to share results and discuss them with others at a workshop in Indonesia in 2020.