December 2009 – Ian Poiner

December 2009 – Ian Poiner, Chair of the CoML Scientific Steering Committee (SSC) and Chief Executive Officer of the Australian Institute of Marine Science

Melissa Brodeur: On November 23, 2009 CoML released its latest findings about the deep sea – a world beyond sunlight (see Cover Story). Can you tell us a little about the findings?

Ian Poiner: The release featured results from five of the 14 CoML field projects. The five focused on the deep sea. They found many new species that live in the largest, but least known, habitat on Earth. The deep sea is a place of extremes, high pressure, mostly cold (except for the hot vents) and no light. These characteristics created the perception it would be a place of low biodiversity with the odd, weird but wonderful animal adapted to living in an extreme environment. We knew there were some areas rich biodiversity, such as the hot vents and sea mounts but the deep sea benthic and pelagic habitats are not only the largest habitats on the earth but places rich in life. This is the most important finding from the projects. They discovered a great diversity of species evolved to live in these extreme habitats. The other key finding is there is still so much to be discovered. A more complete inventory of what lives there and a better understanding of the physical, chemical and biological process that sustains life in the deep sea are unknowns but knowables. But we also need to better address the great challenges of abundance and distribution information.

MB: What did you find most interesting about the discoveries?

IP: This is a very difficult question to answer as the projects made so many new and interesting discoveries. Many of the deep sea species are different to their shallow water relatives. Not only are they strikingly beautiful but they do some weird and wonderful things to live in these habitats. There is a diversity of adaptations to the cold, dark and high pressure conditions and variable food sources. The result is intriguing life history strategies that enable deep sea species to sustain themselves using, for example, marine snow, whale carcasses or novel chemo-trophic means. The Lamellibrachia tubeworm feeding on bacteria decomposing oil is just one example that raises so many questions. So if I had to make a decision, understanding how animals have adapted to sustain themselves in the deep sea is probably the most interesting aspect of the discoveries for me to date.

MB: How did the researchers study such a deep area?

IP: The ocean can be a difficult and unforgiving place to work. It’s is a place of extremes and long sea expeditions are tough on most scientists. This is especially true for deep sea biologists as they are operating from ships in remote and exposed parts of our oceans. Seeing and sampling the depths of the ocean is also a great challenge, which has lead to many innovative technologies in optics, acoustics, remotely operated vehicles, autonomous underwater vehicles, submarines and smart sensors to mention a few. Even the more traditional sampling tools, such as dredges and trawls, require great skill and special gear. For example, the cable connected to a deep sea dredge or trawl needs to be 2-3 times the depth of water to be sampled. So sampling 5,000 meters deep requires 10-15 kilometers of cable. Researching the deep sea is a difficult and expensive business and this is one reason why the Earth’s largest continuous ecosystem and largest habitat for life is also the least studied.

MB: Why is the deep sea important?

IP: The earth is 70 percent ocean and the deep sea benthic and pelagic habitat is the largest continuous habitat for life on our planet. It is also the least studied and understood. These facts in themselves are reasons why studying the deep sea is important. CoML has shown it is not a barren, lifeless place, rather a place full of life. We live in a time of rapid and accelerating environmental change so understanding the deep sea and its rich biodiversity is important if we are to understand global change, adapt to it and where necessary, develop solutions to mitigate the risk of unwanted outcomes. The deep sea is also a place of potential wealth generation through industries such as seabed mining; oil, gas and possible methane extraction; fishing; and the discovery of novel compounds and other bio-products. All industrial development should be environmentally sustainable and appropriately regulated but the lack of knowledge and inadequate governance arrangements are the two greatest risks to sustainable industries in the deep sea.

MB: Does global climate change affect the deep sea?

IP: Climate change is affecting the oceans through a number of mechanisms, including increasing sea water temperatures and pH, and changes to current regimes. Many of these changes are ‘surface phenomena’ but there will be impacts on the deep sea. The ocean conveyor belt—which allows cold, dense waters to sink to the deep ocean and nutrient-rich waters to rise in both the Northern and Southern Hemispheres—will slow in response to climate change. This is likely to impact the deep sea as well as the productivity of the shallow ocean. With a changing ocean there is likely to be changes to trophic networks, which will also impact deep sea biodiversity. The threats of climate change again highlight the need to address our lack of knowledge about the biodiversity of the deep sea.

MB: On a less serious note, if you were stuck in a submersible (which I have heard you liken to the trunk of a car), who would you most like to be stuck inside with you?

IP: Given my size… someone small!

MB: Is it true that you have swum in each of the oceans?

IP: One of my goals in life is to swim in all the world’s Oceans and Seas. I have swum in four of the five oceans with the Arctic still to happen. Excluding land locked seas, and depending on your definition of a sea, there are about 100 of them in our oceans. To date I have swam in 40 but being a person of the tropics with a low tolerance to the cold my challenge is the seas of the colder parts of our oceans but from a selfish perspective could be one of the few benefits of a warming ocean!

Do you want to know more about Ian Poiner and CoML’s findings in the deep sea? Check out this video of Ian being interviewed on CNN.