Previous SOI seminars

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, we have developed and deployed numerous underwater vehicles and imaging platforms in support of applications in engineering science, marine ecology, archaeology and geoscience. We have 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. We have 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.

The Polar Oceans are defined by ice and dramatic shifts between endless day and night. While the marine environments at the poles are some of the harshest on Earth, animals have still found ways to survive. Marine mammals exhibit amazing adaptions to thrive but might be threatened by environmental change. Understanding the impact climate change has on these animals helps us to not only better protect these species, but also to conserve biodiversity in these fragile ecosystems.  Research in the polar regions is also important and relevant to everyday life as it has the potential to benefit humanity, inform the sustainable use of resources, help protect the planet and generate economic and social impact.

In this talk, I will highlight some work I have done in the past years in both Polar regions from investigating marine mammal behaviour to describing oceanographic processes potentially driving environmental change. I will also show highlights from the first cruise into the Amundsen Sea, Antarctica as part of the International Thwaites Glacier Collaboration to understand how quickly the Western Antarctic Ice Sheet could melt.

The aim of this seminar is to give an overview of the ongoing research that is being conducted by St Andrews as part of the Antarctic Circumnavigation Expedition (ACE, https://spi-ace-expedition.ch/). From December 2016 to March 2017, scientific teams from all over the world took part in this expedition to expand our understanding of the Southern Ocean (from biology to climatology to oceanography). Our project on ACE was to study the acoustic prey landscape of Antarctic deep-diving predators (King Penguins and Southern Elephant Seals). Mesopelagic fish (e.g. myctophids), zooplankton and other organisms migrate down to the mesopelagic zone (200-1000m) to avoid visual predators during the day. There, they form layer-like aggregations known as Deep Scattering Layers (DSLs), which can be detected by echosounders. Myctophids are potential resources for fisheries but are also important in the diets of Antarctic predators such as King Penguins and Elephant Seals. During the ACE expedition, we investigated the interaction between myctophids and these predators by monitoring simultaneously DSL characteristics and predator foraging behaviour. We compiled a dataset of geographic variability in DSL depth and echo-intensity throughout the Southern Ocean. Concomitantly, we collected track data, dive profiles and accelerometry data from King Penguins breeding at South Georgia, and tack and dive data from Elephant Seals. We found that DSL echo-intensity (a proxy of biomass) can be predicted well from sea surface temperature, and that sun angle plays a major role in DSL depth. Habitat modelling techniques revealed that King Penguins preferentially selected habitats based on DSL availability. They targeted zones characterised by dense and shallow DSLs. However, a more detailed analysis of diving activity showed that the penguins’ dive depths were generally shallower than the DSL depth, indicating that they might not feed on the layers themselves, but instead target prey patches above the DSLs. For Elephant Seals (work ongoing) there are some good alignments between dive depths and DSL depths. One objective of our work aims to improve understanding of predator-prey interactions to inform conservation management before any large-scale fisheries exploitation of mesopelagic fish begins.

Harbour seals are common residents in the UK waters and although they are a protected species, numbers have substantially decreased in some regions. Reduced prey availability and quality, possibly exacerbated by competition with increasing numbers of grey seals, construction and operation of offshore renewables, are candidate drivers of this decline. Design of a reliable tool which can predict long-term consequences of a combination of such factors on seal movement and population dynamics is therefore important. There is a crucial need for regulators, developers and NGOs to be able to make ‘what if’ scenario predictions and to model the combined effect of marine stressors on seal populations.

I will present design concept and initial results from a behaviour-based, spatially explicit, individual-based model using one month simulations from East Coast of Scotland as an example. I am using pattern-oriented modelling approach, where observed patterns, such as spatial distribution of seals (density, trip extent and duration), their time-energy budget and changes in body conditions over time are compared to modelled results. I will also discuss how the model is going to be further developed and how it can be used as a tool to simulate harbour seal movement and life history under plausible scenarios of environmental change.

The effectiveness of Marine Protected Areas for mobile species has been, and still is, questioned. For static management to be effective it must either protect a suitable critical life history stage or the species must demonstrate some level of fidelity to an area. Either of these scenarios require detailed knowledge of the species to determine if an MPA would be a suitable management strategy. This level of data is rarely available, especially in the marine environment. However, there are some species for which we are beginning to gather sufficient data, one of these is the Flapper skate (Dipturus intermedius). This species is currently the only UK elasmobranch to have an MPA as part of its management strategy; the Loch Sunart to the Sound of Jura MPA. In order to achieve this, this species and the MPA have been the focus of numerous studies, bringing together many stakeholders. This talk will give an overview of the research behind the designation of the MPA, and current research in the area, highlighting how research and management can work together.  

Massimiliano Rosso is a senior researcher at the CIMA Research Foundation in Savona Italy.

Cuvier’s beaked whale (Ziphius cavirostris G. Cuvier, 1823) is the only beaked whale species commonly found in the Mediterranean Sea. Until recently, species presence in this area was only inferred from stranding events. The Mediterranean population of Cuvier’s beaked whale is genetically distinct from the Atlantic, and subject to a number of conservation threats, in particular underwater noise. Dedicated cetacean surveys in the NW Mediterranean Sea have started in 2002 increasing the knowledge of the distribution and abundance of Cuvier’s beaked whales in the basin, even though many areas still remain unexplored. The talk will present an updated analysis of available sighting, mark-recapture and stranding data, focusing on the atypical mass strandings that have occurred in the Mediterranean Sea since 1963. Data from the NW Mediterranean Sea have been analyzed for habitat modelling studies for that area, confirming the species preference for the continental slope and its particular association with submarine canyons, as has also been found to be the case in other areas of the world. Using a robust dataset, population size has been estimated for the Ligurian sea and the photo-id data have been used to study the natural marking on this specie and to create a reliable sex identification method using natural marking patterns.

Biotic connectivity between ecosystems can provide major transport of organic matter and nutrients, influencing ecosystem structure and productivity, yet the implications are poorly understood owing to human disruptions of natural flows. When abundant, seabirds feeding in the open ocean transport large quantities of nutrients onto islands, enhancing the productivity of island fauna and flora. Whether leaching of these nutrients back into the sea influences the productivity, structure and functioning of adjacent coral reef ecosystems is not known. I address this question using a rare natural experiment in the Chagos Archipelago, in which some islands are rat-infested and others are rat-free. I found that seabird densities and nitrogen deposition rates are 760 and 251 times higher, respectively, on islands where humans have not introduced rats. Consequently, rat-free islands had substantially higher nitrogen stable isotope (δ¹⁵N) values in soils and shrubs, reflecting pelagic nutrient sources. These higher values of δ¹⁵N were also apparent in macroalgae, filter-feeding sponges, turf algae and fish on adjacent coral reefs. Herbivorous damselfish on reefs adjacent to the rat-free islands grew faster, and fish communities had higher biomass across trophic feeding groups, with 48% greater overall biomass. Rates of two critical ecosystem functions, grazing and bioerosion, were 3.2 and 3.8 times higher, respectively, adjacent to rat-free islands. Collectively, these results reveal how rat introductions disrupt nutrient flows among pelagic, island and coral reef ecosystems. Thus, rat eradication on oceanic islands should be a high conservation priority as it is likely to benefit terrestrial ecosystems and enhance coral reef productivity and functioning by restoring seabird-derived nutrient subsidies from large areas of ocean.

Newcastle University have been advancing the field of underwater acoustic communication and positioning for over 25 years and the most recent developments are focused on ultra-low cost, low energy devices to enable the cost effective deployment of long term, large scale underwater wireless sensor networks. Results from the EPSRC funded programme USMART will be described, demonstrating that reliable communication and positioning can be achieved, over distances up to 2km, using an acoustic modem device that can be manufactured for around £50 in large quantities. Novel work on methods to minimise the environmental impact of acoustic transmissions is also discussed. The research programme to develop smart underwater sensing networks from these technologies will be described along with projects focusing on exemplar applications including cost effective marine mammal surveys, micro-AUV swarming and tagging/location of fishing gear to mitigate marine litter issues.

Rebecca Lent is the Executive Secretary of the International Whaling Commission (effective 1/1/18). Rebecca worked with the U.S. government for 25 years, most recently as the Executive Director of the U.S. Marine Mammal Commission, and as the Director of the Office of International Affairs at NOAA Fisheries (National Marine Fisheries Service – NMFS). Her positions at NMFS included serving as U.S. Commissioner/Acting Commissioner in two regional tuna management organizations, a one-year secondment at the World Bank, and as NMFS Regional Administrator in California. Rebecca is an economist by training, and started her career in academia in Québec, Canada.

In her talk, Rebecca is going to give an overview on how the IWC and all its partners can address some of the new threats to marine mammals. The 1946 International Convention for the Regulation of Whaling called for the ‘proper conservation of whale stocks and thus the orderly development of the whaling industry.’ ‘Real world’ economics is in fact at the origin of the Convention, which came at a time of financial hardship for the whaling fleets as catches were declining. It was also a hungry post-WW II world looking for protein and animal fats. As substitutes for whale oil developed, the prices for whale fats declined, and resulted in less whaling altogether. Many of the emerging threats to marine mammals are what economists call ‘externalities’ of other activities such as fishing (bycatch), shipping (underwater noise, marine pollution, ship strikes), energy production (acoustic testing, drilling) and use (emissions and climate change). While the use of economics and other social sciences is not yet part of the approved plan by the Commission, its potential can be explored.

Growing evidence suggests that anthropogenic litter, particularly plastic, represents a highly pervasive and persistent threat to global marine ecosystems. Multinational research is progressing to characterise its sources, distribution, abundance and impacts so that interventions aimed at reducing future inputs can be developed. Here, two elements of Sarah’s PhD research at the University of Exeter and Plymouth Marine Laboratory will be presented. The first, a 10-year nationwide assessment of marine litter on British beaches whereby citizen-science beach clean data were analysed to better understand the composition, spatial distribution and temporal trends of coastal debris. The second, an investigation into the ingestion of microplastics (plastic <5mm in size) by marine mammals, using both captive animals to garner information on trophic transfer of microplastics, and animals that stranded around the British coast to examine the extent of microplastic ingestion in wild marine mammals.

Bio-logging technology allows scientists to understand the underwater behavior of marine animals in unprecedented ways. From multi-sensor tags that collect fine-scale data for short durations to satellite-linked tags that collect more coarse data over long time periods, bio-logging tools can be used to better understand the risks that marine animals face from a myriad of anthropogenic sources.  I will use two example studies to illustrate how these different tools are being used to better inform conservation and management needs.  Blue whales in California waters were studied using short-duration motion-sensing and acoustic tags as part of a behavioral response study to understand the impacts of mid-frequency navy sonar.  Humpback whales were studied using a combination of motion-sensing and satellite-linked time-depth recording tags to better understand overlap with the krill fishery in the face of a rapidly changing ecosystem around the Antarctic Peninsula.  These examples highlight how detailed information on the behavior and ecological interactions derived from bio-logging tools and environmental sampling is critical to understand risk, and how we can better conserve and protect these species and their ecosystems.

Owing to extreme selection pressures for rival assessment, the northern elephant seal (Mirounga angustirostris) provides an optimal social model to explore the role that learning plays in the communication system among breeding males. During the breeding season, males compete to establish dominance that control access to large groups of females. Vocal signaling plays an important role in mitigating costly fights between males, as the majority of interactions are typically resolved through the exchange of vocal signals. Through the use of recordings, behavioral observations, and playback experiments, our research group has evaluated the information encoded within these specialized calls, and how listeners assess and respond to the vocalizations of their most familiar competitors. Our results demonstrate that each adult male possesses a unique acoustic signature, and vocal variation among males supports individual recognition through the process of associative learning. We then how males develop the calls they produce over their lifetime, and explore the underlying social and demographic conditions that support a system based on individual recognition. This talk will provide a holistic approach to describing the vocal behavior of the male northern elephant seal, and insight into other marine mammals that use acoustic communication during important life-history events.

Annual Buckland Lecture

The talk will be given by the 2018 Buckland Professor of Fisheries, Dr Ronald Campbell, Tweed Foundation, who will be supported by Dr John Armstrong, of the Freshwater Fisheries Laboratory and a Trustee of the Buckland Foundation.

Norwegian killer whales (Orcinus orca) were relatively well-studied from 1988 through 2005 at the seasonal grounds of the Norwegian Spring Spawning stock of Atlantic herring (Clupea harengus). Studies mainly focused on photo-identification, feeding behaviour and acoustics. Close to 1,000 killer whales were associated with the wintering herring in the northern fjords and Norwegian killer whales are widely considered to be herring-specialists. However, very little research has been conducted outside the seasonal herring grounds, and dietary and habitat use patterns in other regions and at other times of the year remain unknown. This seminar will give an overview of a long-term project investigating northern Norwegian killer whales year-round, focussing on population studies and feeding ecology. Since 2013, data have been collected in all months of the year, providing new insights into individuals, patterns of occurrence, feeding behaviour and diet. The library of ID-photographs ensures the continuation of the longitudinal studies initiated by colleagues three decades ago. Preliminary results and some of the main findings of this ongoing project will be presented.

In recent years, large aggregations of humpback whales and killer whales have been observed in fjords near Tromsø (Northern Norway) during the winter. The whales were attracted by herring that was overwintering in these fjords. As the whales come into the fjords, they encounter areas with an abundance of human activities, such as commercial and recreational shipping and (coastal) fisheries. In order to mitigate the overlap between whale movement and human activities, it is important to understand how the whales use these fjords. In this PhD I use telemetry tracks and dive patterns from humpback whales and killer whales, in order to develop movement models and species distribution models that can be used to identify and characterize areas that are highly used by whales in various behavioral states. The output of these models can be compared with fishing and shipping activities to identify areas of overlap, and to study the whales behavior in areas with a lot of human activities.

South Africa’s large exclusive economic zone includes the Indian, Atlantic and Southern Oceans. Management of this ocean space has traditionally been undertaken within sectors, leading to conflict amongst sectors, and between sectors and the need for environmental protection. As the demand for ocean space and marine resources increases, in response to a growing oceans economy, a more integrated approach to management is required to ensure that both ecological and socio-economic objectives are met. Marine spatial planning (MSP) has emerged in many countries as an effective process to achieve this integration, and in 2016, South Africa became the first African country to draft MSP legislation. In this seminar, I present seven trans-disciplinary research projects that address challenges for implementing an ecosystem-based approach to MSP in South Africa. Projects include the analysis of microbial community dynamics as a measure of marine ecosystem health and the response to environmental change; the use of biological traits to assess ecosystem condition of rocky reefs; a model to assess the impacts of warming and ocean acidification on the southern Benguela food web and fisheries; spatial management options for marine fisheries in South Africa; the use of low-cost fishing exclusions to improve the conservation of a top predator; the assessment and development of sustainable boat-based marine tourism; and the development of a system-dynamics model to support marine spatial planning in Algoa Bay, South Africa. I conclude with lessons learned, and recommendations to advance ecosystem-based approaches to MSP globally, within a systems-thinking framework.

Collaborators: Rosemary Dorrington, Kelly Ortega Cisneros, Gwenith Penry, Lorien Pichegru, Jodie Reed, Kaylee Smit, Estee Vermeulen

This talk presents a noise avoidance model for migrating gray whales. The model assumes each individual animal has a maximum exposure threshold which it will tolerate, which we call its avoidance threshold. The model assumes that as animals approach a consistent noise source, they will adjust their course as little as possible to insure that their individual sound exposure, or received level, will not exceed its avoidance threshold. The model estimates the probability mass function (PMF) of the avoidance threshold for a population by comparing the histograms of the closest point of approach (CPA) to the source between playback and control conditions. Repeating the analysis using bootstrap resampling techniques on the CPA data provides an interval estimate of the avoidance threshold PMF at each received level. The avoidance index PMF was estimated for gray whales from CPA data observed during exposure to a single U.S. Navy SURTASS-LFA source in 1998. The median avoidance threshold for this population was estimated to be 134 /- 3 dB re 1 uPa, with 90% confidence.

[Work supported by US Office of Naval Research]

Speaker Bio:
Dr. John Buck received his Ph.D. from the MIT/WHOI Joint Program in Oceanographic and Electrical Engineering in 1996. He joined the faculty of UMass Dartmouth later that year, and is presently a Professor in the ECE Dept. His honors include the University of Massachusetts Manning Prize for Excellence in Teaching (2016), the IEEE Education Society’s Mac Van Valkenburg Early Career Teaching Award (2005), the UMass Dartmouth Faculty Federation Leo M. Sullivan Teacher of the Year Award (2008), an ONR Young Investigator Award (2000) and an NSF CAREER award (1998). He is a Fellow of the Acoustical Society of America. His research interests include signal processing, underwater acoustics, animal bioacoustics and engineering pedagogy.

In long-lived species, males and females are expected to allocate their time to mating, guarding behavior and self-conditioning behavior during the breeding period. In the chick-rearing period, many species of seabirds display a unique behavioral adaptation for managing their conflicting demands known as dual foraging, in which long trips, largely for self-maintenance, are alternated with short trips, which are primarily for offspring care. In the mating period, seabirds also allocate their time to mate and to forage. However, there is no study how they manage their time during the mating period. In this study, we examined male’s and female’s allocation of their time using geolocators in streaked shearwaters. We found that females took longer trips than males and went to the more distant area of the sea. They did not change their trip length after they stay together with their partner. However, male shearwaters mainly took one-day trips, and they extended their trip length if they met their partner at the nest. This suggests that male shearwaters determine their trip length based on the presence or absence of paired female to control their time between mating and foraging.

Join seminar with CBD, location of the seminar will be in the Dyers Brae Seminar Room.

Within the Southern Ocean, the Northern Scotia Sea contains the largest seasonal uptake of atmospheric carbon dioxide measured yet. In this region, zooplankton can contribute significantly to the deep ocean carbon export and to the food web. However, year-round data for zooplankton abundance in this region are rare, due to the current difficulty of sampling in the austral winter using conventional sampling methods, such as plankton net tows. Moored time-series sediment traps are primarily used to gather information on vertical particle fluxes in the oceans. However, the accidental capture of zooplankton (so called ‘swimmers’) in time-series moored sediment traps deployed year-round provides a unique and much-needed insight into the seasonal variation of zooplankton abundance and diversity in remote areas such as the Southern Ocean. In this study, we show results of pelagic amphipods collected as swimmers from two years (2015-2016) of moored sediment trap deployment at 400m, located in a site in the Northern Scotia Sea close to South Georgia (SCOOBIES mooring platform). Amphipods represent a key link in the food web between meso-zooplankton and higher trophic organisms. Organisms were counted, photographed and measured using Image J software. Dry mass and carbon content were indirectly calculated. In both investigated years, Amphipod numbers reached the seasonal peak in the austral late summer-early autumn, decreasing until the next summer season. A shift in Amphipod assemblage composition was observed in both 2015 and 2016 with Hyperiidea and Gammaridea dominating the total Amphipod assemblage in the austral winter and summer respectively. The data presented, serves as a baseline for future research to explore the opportunity of using sediment traps as tools to monitoring seasonal and inter-annual variability of zooplankton in the Southern Ocean.

Dr Richard Sherley is an ecologist and conservation biologist with the Bristol Zoological Society and the Environment and Sustainability Institute at the University of Exeter.

His research focuses on the population demography, behaviour and conservation of seabirds, particularly how they interact with human impacts in the marine environment.

His work is funded by the Leiden Conservation Foundation and a number of other charitable trusts.