Beyond Challenger: a new age of deep-sea science and exploration

The voyage of HMS Challenger from 1872 to 1876 is often credited with laying the foundations of modern oceanography, as a consequence of its global scope and multidisciplinary approach, which opened up the "sealed interior" of the oceans described by Matthew Fontaine Maury two decades earlier. But the Challenger expedition did not spring fully formed into existence; it built on knowledge and experience obtained by earlier expeditions, such as the Royal Society's charters of HMS Lightning in 1867 and HMS Porcupine in 1868 and 1869 for scientific investigations in the northeast Atlantic. Obtaining government backing for a global voyage of exploration also involved considerable lobbying by William Carpenter, through public talks and mobilising the support of notable 19th century scientists including Charles Lyell, Thomas Huxley, John Tyndall, and William Herschel. The eventual award of £200,000 for the Challenger expedition, equivalent to around £29.5 million today, was driven by promised vistas of scientific discovery and the importance of understanding more about the ocean floor for laying submarine telegraph cables. In this talk Dr Copley will outline the circumstances that gave rise to the Challenger expedition, and how it secured a lasting legacy among other voyages of ocean exploration during the same period.

In the early days of deep-sea exploration, it was quite acceptable in the scientific community to wonder if any animals at all can live in the deep sea, and if they were there, what on earth they might look like. Ancient lineages of life that have long since gone extinct in our shallow seas? Giant monsters with peculiar adaptations to the cold and dark? Today these old-fashioned questions would probably not pass through a grant-awarding committee. Simply knowing what is there is not enough. Science demands numbers, functions, genomes, applications. But the simple truth is that every deep-sea biologist, waiting on the back deck of a ship for their samples to come up, or watching the screen of an ROV, still ponders these questions - with a remarkably open-mind as to what on earth they might find. It is a common refrain to hear that ‘most of the deep-sea is unexplored’. However, this is not entirely true. We do actually have rather a lot of samples and knowledge of the deep sea. The main issue is that those samples, and the treasures they hold, are not being described, archived and communicated in the comprehensive manner that so defined the Challenger expedition. In my talk, I will propose a 21st century approach to an old problem - what lives in the deep sea?

Hydrothermal vents form ephemeral deep-sea habitats that occur along seafloor spreading centres and subduction zones as well as in association with volcanic seamounts. Diverse chemotrophic microbial communities form the base of the food web. These bacteria take advantage of redox disequilibria and a variety of carbon sources to gain “energy” for growth and cell maintenance. Ultimately, this chemosynthetic primary production supports localised, high metazoan biomass in relation to the surrounding deep-sea. Stable isotopes are often used by geochemists, microbiologists and ecologists to understand geochemical processes and “energy” flow through biological systems. Ecologists require an understanding of the basal and primary producer stable isotope dynamics in order to place in context the stable isotope values of metazoan consumers. However, there are often spatial and temporal mismatches in sample collection within many hydrothermal vent fields which hinder our understanding of trophic interactions and “energy” flow from the mantle to the consumer. There is currently a requirement for synthesis within the stable isotope literature that will identify key data gaps, which may bridge disciplines, to be filled. This will allow the development of multi-level isotopic landscapes or “isoscapes” over hydrothermal vent fields which will provide better understanding of the primary production utilised by consumers. Moving forward, these “isoscapes” need to work in parallel with the development of processed based models that will allow analysis and prediction of key biochemical processes that shape the “energy” landscape within hydrothermal vents.

Expanding global interest in the extraction of living and non-living resources from Areas Beyond National Jurisdiction creates both opportunity and challenge. Opportunity for economic benefits from the deep sea juxtaposes challenges in sustainable use of the Earth’s largest, most pristine, and least known habitats. The deep ocean faces stressors from distant sources as climate change warms, acidifies and de-oxygenates deep waters in which microplastics and other human waste are now nearly ubiquitous. Fortunately, new technologies paired with developments in marine conservation and area-based management tools, such as marine protected areas (MPA), offer potential pathways to effective strategies for sustaining deep-sea ecosystems. Rapidly emerging technologies (genetics, imaging, sensors and observation platforms, data and modelling) can inform effective MPA design and management in deep-sea environments, drawing on new approaches to map habitats, evaluate their spatial extent and connectivity, and informing size and spacing elements. Collectively, these tools can help address the unique conservation issues for deep-sea biota (sparse data, low population size, many rare species, examples of late reproducers with limited fecundity) and ecosystems (lack of habitat maps, expansive habitat types interspersed with discrete and sometimes rare and specialized habitats) that require considerations beyond those that drive MPA design in terrestrial and coastal habitats. This discussion will draw from MPA examples in which we consider the need to include a 3D dimension in “protection” when addressing deep-sea ecosystems.

This talk will describe insights gained from a decade of autonomous marine systems development at the University of Sydney’s Australian Centre for Field Robotics. Over the course of this time, this group has developed and deployed numerous underwater vehicles and imaging platforms in support of applications in engineering science, marine ecology, archaeology and geoscience. The group has operated an Australia-wide benthic observing program designed to deliver precisely navigated, repeat imagery of the seafloor. This initiative makes extensive use of Autonomous Underwater Vehicles (AUVs) to collect high-resolution stereo imagery, multibeam sonar and water column measurements on an annual or semi-annual basis at sites around Australia, spanning the full latitudinal range of the continent from tropical reefs in the north to temperate regions in the south. The program has been very successful over the past decade, collecting millions of images of the seafloor around Australia and making these available to the scientific community through online data portals developed by the facility and affiliated groups. These observations are providing important insights into the dynamics of key ecological sites and their responses to changes in oceanographic conditions through time. The group has also contributed to expeditions to document coral bleaching, cyclone recovery, submerged neolithic settlement sites, ancient shipwrecks, methane seeps and deepwater hydrothermal vents. The talk will also consider how automated tools for working with this imagery have facilitated the resulting science outcomes and will explore opportunities to extend these techniques to the study of deep-sea science and exploration.

There are many applications in marine science and monitoring that require high-resolution images of the seafloor to be obtained. However, the resolution of underwater observations are often at a trade-off with the extent over which they can be made, and this limits their usefulness in non-uniform seafloor environments where the distribution of features varies over spatial scales much larger than the footprint that can be observed, for example in a single image frame. This talk will describe recent efforts to address scale relevance in seafloor imaging applications by using autonomous underwater vehicles instrumented with systems that can image the seafloor from different altitudes, and build multi-hectare 3D visual reconstructions of the seafloor with resolutions with sufficiently high-resolution where needed. This allows continuous wide-area, multi-resolution 3D reconstructions of the seafloor to be generated, allowing patterns to be explored and interpreted over a large range of spatial scales that would not otherwise be possible. This approach will be described giving examples of data recently obtained in deep-sea hydrothermal vent and gas hydrate fields.

AI in general and machine learning in particular have created a great deal of recent interest, not to mention hyperbole. In this talk, Jeremy Wyatt and Mohan Sridharan will give a whistle-stop tour of the current state of AI. The speakers shall describe fundamental algorithmic advances in perception, reasoning, manipulation and learning. The emphasis will be on the nature and properties of algorithms that may have utility in deep-sea exploration. Although the speakers are not currently working on AUVs, they will discuss some case studies from their own work and that of others. The talk will also cover the obvious challenges in practical deployment and some ways that these challenges may be overcome.

A severe bottleneck exists in the ecological study of our oceans and seas. This has arisen because net-sampling, having been the mainstay of biological oceanographers for over a century, has not provided sufficient data of the distributions, dynamics and populations of important taxa to answer questions posed by researchers today and in the future. In the last decade or so, in-situ, towed or ship-based imaging instruments have been developed that potentially may be able to address the shortfall. These instruments can, and will, provide denser spatial and temporal sampling that is more cost-effective than is possible with net sampling. However, there is problem. We do not have enough skilled people to identify the video and photographic hauls from the water.

Artificial Intelligence has been mooted as the solution, automating identification using the latest ideas in Deep Learning. However, to be successful in using computers to automate taxonomic identification of organisms, the machines will have to learn from the vast literature that describes our natural world. Deep learning is beginning to revolutionise computer-based visual recognition, but it must be tied to natural language and the descriptions that people make in the scientific literature to be able make the transition from laboratory-sized machine classifiers to globally useful tools. We must integrate the existing taxonomic knowledge that is written and drawn with emerging AI tools. Culverhouse will explore this issue.