A Robot Called the "Swiss Army Knife of Marine Research" Is on the Prowl for the "Jelly Web"

A research team from the GEOMAR Helmholtz Centre for Ocean Research Kiel is looking for jellyfish in the depths of the ocean, among other things — and it's drafted in a specially-built robot to track them down.

"It is very likely that we will discover new species on this cruise," Jan Dierking, PhD, predicts of the planned launch of expedition MSM126, which will explore deep-sea habitats around Madeira. "We want to see how organisms in the open water are linked to the deep sea: who eats whom, who competes with whom? I am very excited to see what the eye on the seabed will reveal."

That "eye" is part of a payload of equipment being taken on the mission, dubbed Pelagic in Situ Observation System (PELAGIOS). This will be joined by echosounders and towed cameras, dubbed the Ocean Floor Observing System (XOFOX), which will map three areas around Madeira — a deep-sea canyon, an underwater plateau, and a submarine ridge — from depths of 50m to 3km (around 164 feet to 9,800 feet).

For direct sampling, though, the team has what it calls the "Swiss Army knife of marine research," ROV PHOCA, a remotely-operated submersible robot which can reach depths of 3km while feeding back live high-definition video through an optical tether. During the mission the robot will be used to take samples using what is highly-technically termed the "slurp gun," and to investigate what happens during a "food fall" where organic materials sink from the upper sea to the depths.

A major focus of the mission is on jellyfish, and how they contribute to the food web in the ocean. "This group of organisms is very diverse," says Henk-Jan Hoving, PhD, of the creatures. "Some of them can grow to tens of metres in length. Some are predators, feeding on crustaceans, fish or other gelatinous organisms. Others rely on detritus, the dead and decaying material that is abundant in the water column."

"The jelly web probably plays a crucial role in the processing of organic matter," Dierking adds, "because jellyfish can occur in large numbers, and when such a ‘jelly bloom’ dies, potentially a large amount of this biomass sinks. But for many regions, including Madeira, we don't know how much of it actually reaches the seabed or who feeds on it."

The mission launched today in Portugal, and is due to end in Spain on 4 March; during the mission, schoolchildren will be invited for a question and answer session, the researchers have confirmed. More information is available on the GEOMAR website.

Main article image courtesy of Henk-Jan Hoving/GEOMAR.