May 11, 2017
Day 1: Chief scientist and voyage leader, Dr Tim O’Hara
Senior curator, marine invertebrates at Museums Victoria
Welcome to day one of ‘Blogging the abyss’.
This is my first time as an expedition leader and I’m really excited about the voyage. I think it will be technically challenging, but we have a terrific team of experienced people from around the world, including experts in all the different groups of species we’re expecting to find in the abyss.
The abyss is the largest and deepest habitat on the planet. It covers half the world’s oceans and one third of Australia’s territory, but it remains the most unexplored environment on Earth. We know that abyssal animals have been around for at least 40 million years, but until recently only a handful of samples had been collected from Australia’s abyss. We expect to catch everything from sea fleas, crabs, shrimps and snails, to anglerfishes, rattails, and sharks, and there will be a whole suite of animals that we’ve never seen before.
Research in other parts of the world has found that the animals that live in the abyss have evolved highly unique ways to survive in this world of crushing pressures, no light, little food and freezing temperatures. At these huge depths it is so dark that creatures often have no eyes or produce their own light through bioluminescence. As food is scarce, animals are often small and move slowly: it’s a world of jelly and fangs, with miniature monsters gliding up and down waiting for prey. We hope to keep some of the specimens alive in onboard aquaria to study some of these unique adaptations.
Our seafloor mapping and biological sampling will take place in seven of Australia’s Commonwealth marine reserves, starting tomorrow at the Freycinet reserve off eastern Tasmania. By increasing our understanding of these places and the highly adapted creatures that live in them, the voyage will help Parks Australia to manage these important and poorly understood parts of our national marine estate. We will use high-tech multi-beam sonar to map the structure of the seafloor, and cameras, nets and sleds to sample habitats at 2500 and 4000 metre depths. I will take up to seven hours to lower and raise this equipment from the seafloor.
The abyss seems a long way away, but really our influence on the planet is almost global now, so an important part of our mission is to look for microplastics in the water and on the seafloor, to try and find out how much of the refuse of our life in Australia is ending up in the deep sea.
What we find on this trip will be crucial to understanding Australia’s deep-sea habitats, their biodiversity and the ecological processes that sustain them. This will assist in its conservation and management and help to protect it from the impacts of climate change, pollution and other human activity.
What I’m really excited about is mapping the abyss: what patterns are we going to find down there? Are the animals off Tasmania the same as those off Queensland? Surprisingly for small, slothful, malnourished animals, abyssal critters really seem to get around: some species occur from Russia to Antarctica. One theory is that their eggs and larvae can travel great distances. With a bit of yolk to keep them going, fertilised eggs may drift for years in deep-ocean currents, in a sort of suspended animation, until they find exactly the right environment to grow.
We’ll be taking videos and photographs throughout the voyage, to show all Australians what lives deep in their deep seas. I hope you enjoy following our voyage.