A team from the UK and Japan has managed to track down and film the deepest ever living fish. They found the 17-strong shoal chillin’ (literally) in a trench in the Pacific, 7.7km down from the surface. One of the scientists, Monty Priede from the University of Aberdeen, described the fish as “surprisingly cute”.
The team was investigating the Hadal zone – an area of the Ocean that sits 6,000m -11,000m below sea level. The deep sea is split up into the Bathyal, Abyss and Hadal zones, and Hadal is the deepest of the three. There are very few places in the world deep enough to fit into this category, and most lie in very narrow trenches around the Pacific rim.
Of course, living at 7,703m below the surface has its drawbacks. Director of Oceanlab at the University of Aberdeen, Professor Priede, said:
“There are three problems: the first is food supply, which is very remote and has to come from 8km (5 miles) above.”
“There is very high pressure – they have to have all sorts of physiological modifications, mainly at the molecular level.”
“And the third problem is that these deep trenches are in effect small islands in the wide abyss and there is a question of whether these trenches are big enough to support thriving endemic populations.”
The fish, who normally live in utter darkness, are completely blind, and use vibration receptors on their snouts to navigate and find food. The researchers expected fish at this depth to be relatively sedate to conserve energy, but found them to be surprisingly active.
The team’s next expedition will take place in March 2009, and they’ll be probing down to between 6,000m and 9,000m. Alan Jamieson reckons they’ll find more fish: “Nobody has really been able to look at these depths before – I think we will see some fish living much deeper.”