NIWA's Kaharoa sets sail for the Kermadec Trench, in search of new and strange deep-sea fish
Scientists set sail on NIWA's research vessel Kaharoa this week to film and explore many aspects of life in deep-sea habitats, and capture fish that are new to science, in the Kermadec Trench, northeast of New Zealand.
A group of scientists from the University of Aberdeen, NIWA, and the Museum of New Zealand/Te Papa Tongarewa will use baited cameras to film species, and collect fish and amphipod samples.
The voyage leader Dr Alan Jamieson, from the University of Aberdeen, says, "There are many areas of seafloor around New Zealand that are largely unknown. Historically, New Zealand scientists have sampled mainly in the top 2000 metres, and in the last couple of years we have concentrated our sampling in ultra-deep depths of 6000 metres and greater. But there has been limited research between the two.
"This time we are concentrating on observations from between 2000 and 8000 metres, to marry up the two depth ranges."
The results from this research will contribute further to the understanding of life in the deepest places on Earth and provide a greater understanding of deep-sea community structure and its function.
NIWA principal scientist Dr Malcolm Clark adds, "From a NIWA and a New Zealand point of view, most of our work has been focused on the continental shelf and slope, and we haven't had the scientific equipment required to go to these extreme hadal depths. So we are learning a lot about the ultra-deep areas we can't sample ourselves."
NIWA's Kaharoa is a small ship capable of deploying free-fall systems, such as the hadal lander, to the deepest parts of the ocean. Bait is attached to the lander to attract animals, which are then filmed by a high-resolution video camera. The scientists will have four landers on the seafloor at the same time.
An expected highlight of the trip will be getting footage of the endemic snailfish, Notoliparis kermadecensis, at depths of 7000-7500 metres.
The snailfish in the Kermadec Trench is a distinct species and it's the only place in the world that they occur.
In the last couple of years, collaborative expeditions between the University of Aberdeen and NIWA to the Kermadec Trench have seen the discovery in New Zealand waters of the 'supergiant' amphipod, a type of crustacean ten times larger than most amphipods. The scientists hope to find and film more of the supergiant amphipods on this voyage.
Dr Jamieson says, "We aim to get live video footage of the supergiant amphipod to see its behaviour, such as what speeds it can swim at, and to find out more about its physiology. There's something obviously unique about its physiology, as it's ten times larger than other amphipods. We also hope to collect a few more specimens, to work out why the supergiant is so large."
The supergiant amphipod was discovered in the Kermadec Trench only very recently. "Its very existence, after all these years of working in deep water, is a kind of symbol of how little we understand from these depths," says Dr Jamieson.
"Another highlight of the trip," says Dr Clark, "will be the deployment of a large baited fish trap. With this we hope to capture some deep-sea fish that are new to science. We have seen unknown species on camera during the 2011 voyage, but we haven't captured any, and so cannot put a name to them."
The fish sampled from the traps will be sub-sampled for various studies. Any new species will be sent to Te Papa, where they will be preserved, researched and stored in the National Fish Collection.
The amphipod samples and any other invertebrates will be registered in NIWA's Invertebrate Collection.
Funding for this voyage is primarily from the Marine Alliance for Science & Technology for Scotland (MASTS), and supported by NIWA's Deep-sea Communities project funded by the Ministry of Business, Innovation and Employment (MBIE).