Envisioning the future of aquatic animal tracking: Technology, science, and application

Electronic tags are significantly improving our understanding of aquatic animal behavior and are emerging as key sources of information for conservation and management practices. Future aquatic integrative biology and ecology studies will increasingly rely on data from electronic tagging. Continued advances in tracking hardware and software are needed to provide the knowledge required by managers and policymakers to address the challenges posed by the world's changing aquatic ecosystems. We foresee multiplatform tracking systems for simultaneously monitoring the position, activity, and physiology of animals and the environment through which they are moving. Improved data collection will be accompanied by greater data accessibility and analytical tools for processing data, enabled by new infrastructure and cyberinfrastructure. To operationalize advances and facilitate integration into policy, there must be parallel developments in the accessibility of education and training, as well as solutions to key governance and legal issues

A new approach to estimating hazard posed by debris flows in the Westfjords of Iceland

The aim of this study is to improve the assessment of hazard posed by debris flows to the people and settlements of northwest Iceland by studying very recent examples from above the town of Ísafjörður and other nearby localities. Debris flows are a recognised hazard in the region: above Ísafjörður, they occur with particularly high frequency and have appreciable volumes (up to 14 000 m3). We have used airborne laser altimeter (LiDAR) and differential Global Positioning System (GPS) data to produce isopach maps of flows that occurred in 1999, 2007, and 2008. Our data show that these flows begin depositing at higher slope gradients and are also more mobile than hillslope debris flows reported by other authors. Above a 19° slope, erosion is initiated independent of the distance along the flowpath. Using the isopach maps and associated field observations, we have found a relationship between ground slope and patterns in deposition volume. We have used this finding as a basis for an empirical model that enables an estimate of the total travel distance and final thickness of future debris flows to be calculated. This has enabled us to identify areas of the town which are at risk; some of these are not obvious without this analysis. This model is notable for its simplicity, which allows future debris flow characteristics to be predicted without the need to determine the precise fluid dynamic parameters of the flow such as viscosity and velocity, which are required to implement more complex models

Search for Neutrinoless Double- β Decay with the Complete EXO-200 Dataset

A search for neutrinoless double-β decay (0νββ) in Xe136 is performed with the full EXO-200 dataset using a deep neural network to discriminate between 0νββ and background events. Relative to previous analyses, the signal detection efficiency has been raised from 80.8% to 96.4±3.0%, and the energy resolution of the detector at the Q value of Xe136 0νββ has been improved from σ/E=1.23% to 1.15±0.02% with the upgraded detector. Accounting for the new data, the median 90% confidence level 0νββ half-life sensitivity for this analysis is 5.0×1025 yr with a total Xe136 exposure of 234.1 kg yr. No statistically significant evidence for 0νββ is observed, leading to a lower limit on the 0νββ half-life of 3.5×1025 yr at the 90% confidence level

Animal-borne telemetry: An integral component of the ocean observing toolkit

Animal telemetry is a powerful tool for observing marine animals and the physical environments that they inhabit, from coastal and continental shelf ecosystems to polar seas and open oceans. Satellite-linked biologgers and networks of acoustic receivers allow animals to be reliably monitored over scales of tens of meters to thousands of kilometers, giving insight into their habitat use, home range size, the phenology of migratory patterns and the biotic and abiotic factors that drive their distributions. Furthermore, physical environmental variables can be collected using animals as autonomous sampling platforms, increasing spatial and temporal coverage of global oceanographic observation systems. The use of animal telemetry, therefore, has the capacity to provide measures from a suite of essential ocean variables (EOVs) for improved monitoring of Earth's oceans. Here we outline the design features of animal telemetry systems, describe current applications and their benefits and challenges, and discuss future directions. We describe new analytical techniques that improve our ability to not only quantify animal movements but to also provide a powerful framework for comparative studies across taxa. We discuss the application of animal telemetry and its capacity to collect biotic and abiotic data, how the data collected can be incorporated into ocean observing systems, and the role these data can play in improved ocean management

Variability in milk fatty acids: recreating a foraging trip to test dietary predictions in Antarctic fur seals

Using Antarctic fur seals (Arctocephalus gazella (Peters, 1875)) in a feeding trial, we investigated the use of milk fatty acids to determine diet. In a regime designed to replicate an average foraging trip, six female seals were fed on four successive days meals of krill (Euphausia superba Dana, 1850; day 1), mixed krill and icefish (Champsocephalus gunnari Lönnberg, 1905; day 2), and icefish (days 3 and 4). Four milk samples were collected from each female, one every 12 h from the time of the last feed. Fatty acid profiles of samples were analysed using canonical discriminant analysis and classification trees. Milk fatty acids could be used to distinguish between seals fed the experimental diet, which was high in fish, and those feeding naturally, thought to be consuming mostly krill. However, there was significant variation between individual seals, which may have been the influence of feeding prior to the experiment. Milk fatty acids remained relatively unchanged over time, suggesting that the influence of dietary fatty acids was averaged over the suckling period. We conclude that, whilst this technique has potential in studying the diet of higher predators, further work is needed to test the underlying assumptions and mechanisms involved in the transfer of fatty acids from the diet into milk