Active life in the deep oceans
Imants (Monty) Priede
Rambo Banjo and the Slickpickers
How can deep-sea animals be observed and studied in their natural environment? What is the source of food for deep-sea animals? How does the type and abundance of fishes change with depth? How active are the fishes of abyssal ocean floor? What is the maximum depth at which fish can survive?
One might think that we know everything there is known about what or who inhabits Planet earth with us, but not quite. What lives down there in the deep oceans at 8000 m or more is still a great mystery. Some people even say that one should invest as much money in understanding what lies in the deep sea as one does in sending rockets into space.
Ever since life in the deep sea was first discovered about 200 years ago most knowledge of these creatures has been gained from dead or damaged specimens dragged up by nets over tens of kilometres from the sea floor behind a ship. The Danish expedition of the HDMS Galathea which circumnavigated the globe during 1950-1952 under the leadership of Anton Brunn, found life at over 10 km depth and gave its name to the world’s deepest fish Abyssobrotula galatheae, represents the zenith of this approach. In 1954 French scientists dove in a bathyscaphe to over 4000 m in the Atlantic Ocean and in 1964 Piccard and Walsh in the bathyscaphe Trieste descended to the deepest point in the world’s oceans, the 10912 m Challenger Deep. These submersibles for the first time made it possible to observe living deep-sea animals in the natural environment.
However, as with space exploration, it is unmanned missions that have played the major role in scientific advances. Low-cost unmanned deep-sea landers can be launched from ships, descend to the sea floor and conduct long term missions unaffected by bad weather before returning to the surface on command with their valuable data. Imants Priede, lead researcher in deep sea science, will describe studies on bathyal and abyssal fishes from around the world and how their distribution, abundance, behaviour and activity has been investigated using autonomous landers. Some deep-sea species have been enticed to ingest baited sonar capsules enabling their swimming movements across the sea floor to be tracked. It is now almost certain that no fishes exist in the oceans deeper than 8000 m and the reasons for this are discussed. New 21st century discoveries of delicate life forms, never seen in net samples, representing some of the most primitive relatives of back-boned animals, will be shown.
Afterwards, in-depth cocktail wonders and explorations while Rambo Banjo and the Slickpickers will be rocking the house with their modern/old country and cheerful tunes.
Entrance to the event is free. No registration is necessary. Doors open at 19:00.