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PREFACE AND ACKNOWLEDGEMENTS -- SECTION I – IN THE BEGINNING -- CHAPTER 1. WADING IN ̶ INTRODUCTION TO THE FISH-BIRD -- General Discussion of Penguins and Substance of the Book -- An Impressive Number of Penguin Species: Evolution of Their Unique Capabilities -- Penguin Species Radiation and the Ontogeny of Their Watery World -- Penguin Evolution: Body Size and Climate -- Penguin Evolution: Radiation into Vacant Niches -- Penguin Evolution: Body Size and Crossing the Sea-Land Boundary -- CHAPTER 2. LAND AHOY! A TIRESOME BUSINESS -- Crossing the Land-Ocean Interface is Affected by Body Size -- Why and How Often do Penguins Come Ashore? -- Tying Land-life to the At-sea Life of Fish-Birds: Foraging and Breeding -- Success Vary with Prey Availability -- Molt ̶Necessary, Brief Respite from the Sea -- SECTION II – PENGUIN MARINE HAUNTS AND FOOD HABITS -- CHAPTER 3.FISH-BIRDS AT HOME IN THEIR OCEAN HABITATS -- Oceanographic Fronts and Water Masses Important to Penguins: General Discussion -- Penguins Require High Productivity Water Masses -- Large Scale: Oceanographic Boundaries and At-sea Distributions of Penguins -- Southern Boundary of the Antarctic Circumpolar Current -- Emperor and King penguins -- Adélie and Chinstrap penguins -- Antarctic Polar Front and Subantarctic Front -- Gentoo and Yellow-eyed penguins -- Macaroni and Royal penguins -- Northern and Southern Rockhopper, Fiordland, Snares penguins -- Subtropical Front and Continental Boundary Currents -- Galápagos, Humboldt, Magellanic, African penguins -- Little penguins -- Meso- and Small-Scale Ocean Processes Facilitating Penguin Exploits -- Island wakes -- Headland wakes -- Shelves and banks -- Submarine canyons -- Shelfbreak fronts -- Marginal ice zones -- Thermo-/haloclines -- CHAPTER 4. SEA FOOD ̶ THE FISH-BIRD MENU -- General Considerations -- Diet Quality: Survival in Cold Water -- Energy density of prey -- Prey size may or may not differ by penguin size -- Prey availability -- Diet Comparison among Penguin Species -- Polar/subpolar, mesopelagic penguins -- Subpolar, demersal/benthic, continental-shelf penguins -- Temperate, upper water column, continental-insular shelf penguins -- Polar, upper water column, continental shelf/slope penguins -- Subpolar, upper water column, continental slope/pelagic penguins -- Polar, upper water column, continental slope/pelagic penguins -- CHAPTER 5. ECOLOGICAL CONSEQUENCES OF DIET COMPOSITION -- Intraspecific Competition among Penguins -- Foraging Range is Key: General Discussion -- Penguin Species' Central-Place Foraging Range Patterns -- Sex Differences in Foraging -- Interspecific Competition Involving Penguins -- Penguins Eat A lot! -- Competition between Penguin Species -- Competition between penguins and other seabirds -- Competition between penguins and marine mammals -- Competition between penguins and industrial fisheries -- SECTION III – THE HARDWARE OF A FISH-BIRD -- CHAPTER 6. THE SLIPPERY SHAPE, HOT AIR AND THE POWERHOUSE – HOW FISH-BIRDS SWIM -- Water – Hard Taskmaster -- The Four Forces Relevant to Penguins -- Vertical Forces – Weight and Upthrust -- Buoyancy: How Much Air Do Penguins Hold? -- Buoyancy and Bergmann's Rule revisited -- Horizontal Forces: Drag -- The Interplay of Drag and Upthrust in Gliding Penguins -- The Drag Devil is in the Detail -- The Penguin Powerhouse -- How Penguins Swim -- The Effect of Upthrust and Body Angle on Penguin Thrust and Lift Forces -- Top Speeds; Power and Upthrust -- The Energy Costs of Swimming -- General considerations -- Specific considerations -- 'Sensible' Swim Strategies and Costs of Transport -- Cruising speed and integrating speed with the cost of transport, -- and beyond -- CHAPTER 7. HOT PENGUINS ̶ COLD WATER -- Resting and Floating Penguins -- The Metabolic Rate of Floating Penguins -- Patterns of Heat Loss to the Sea -- Overall Body Insulation/Conductance -- The Nature of Penguin Insulation -- Active Penguins -- Activity Produces Heat -- Greater Depths Impose a Higher Heat Tax -- Consuming Prey Imposes a Heat Tax -- Embracing The Fish in the Fish-bird -- CHAPTER 8. FISH-BIRDS – THE INSIDE STORY -- Diving Physiology -- Surface issues – Uptake of oxygen -- Oxygen Management Underwater -- Role of the Air Spaces -- Gas Exchange to Body Tissues -- The Aerobic Dive Limit and Beyond -- The Importance of Size in Dive Performance -- Duration -- Depth -- Penguins Under Pressure – Beating the Squeeze and the Bends -- Barotrauma -- Beating the Bends -- A Gut Reaction in Fish-Birds -- Gastric Emptying -- Rotting Food -- The Eyes Have It -- SECTION IV – THE SOFTWARE OF FISH-BIRDS -- CHAPTER 9. EMBRACING THE DEPTHS - THE PENGUIN DIVE -- Submergence -- The time underwater – basic dive descriptors -- Dive profiles -- Dive distance-depth profiles -- Dive aspect ratios -- Horizontal dive directionality/tortuosity -- The Multifunctionality of Dives -- Basic dive types -- T-dives for travelling -- V-dives (water column assessment) -- P-dives (parabolic – prospecting with no prey capture) -- Po-dives (parabolic dives with circular trajectory) -- U-dives (depth-directed prospecting) -- W-dives/Up-dives (U-dives with prey pursuit) -- Depth Duration Effects Over Multiple Dives -- CHAPTER 10. FISH-BIRD STRATEGIES ̶ THE SEARCH FOR FICKLE PREY -- Decisions, Decisions, Decisions – How Fish-Birds Search for Prey -- Heading in the Right Direction -- Dealing with Prey Patchiness -- In-depth Considerations: -- Time-based efficiency -- Energy-based efficiency -- Superficial Considerations: Surface Pauses and Inspired Tactics -- Being Picky about Food -- Fish-Birds and Smart Strategies -- CHAPTER 11. THE FINAL SECONDS – HOW FISH-BIRDS CAPTURE PREY -- Prey Acquisition, a Departure from the Dive 'Norm' -- Performance Metrics for Prey Capture -- Catching Solitary Prey -- Changing buoyancy with depth affects prey capture strategies -- Prey pursuit against interfaces -- Exploiting Aggregated Prey -- Crustaceans -- Fish -- Non-corralling feeding behavior -- Clarity on Limitations of Penguin Vision -- SECTION V – PENGUINS IN A FICKLE ENVIRONMENT -- CHAPTER 12. TURNING THE TABLES – FISH-BIRDS ON THE MENU -- Basic Law of the Sea: Big Fish Eat Little Fish -- Seals as Predators -- Seals' hunting behavior -- Penguins avoiding seals -- Fur Seals as Predators -- Sea Lions as Predators -- Killer Whales as Predators -- Sharks as Predators -- CHAPTER 13. PENGUINS ADJUSTING TO A CHANGING OCEAN -- Penguins Have Always Been Challenged by a Changing Ocean -- Prehistoric response to a changing ocean -- Possible prehistoric changes to penguins' food web -- The Anthropocene: How will Penguins Cope, Now Also Dealing with Humans? -- Response to long-term climate change -- Response to short-term ocean climate variation -- Response to marine pollution -- CHAPTER 14. NOT FORGETTING ̶ -- The Social Side - Behavior and Communication at Sea -- Penguin flock fusion/cohesion -- Penguin flock fission/fragmentation -- Navigation -- Long range -- Medium to short-range -- Understanding the Daily 'Wash' -- Air flux in diving penguins, an aspect of 'washing' -- Are Auks Really 'Northern Penguins'? -- Research Tags – the Flip Side for Evolutionarily-Honed Fish-Birds -- SECTION VI -- CHAPTER 15. PENGUINS ̶ WHY THE HYPE? -- Sources of Hype -- Us -- Many people -- Researchers -- The Transition -- The fascination of species -- Beyond the transition -- Role in Ecosystems -- Biomimicry -- Our Last Word.

Vertebrates are recognized as sentient beings. Consequently, urgent priority is now being given to understanding the needs and maximizing the welfare of animals under human care. The general health of animals is most commonly determined by physiological indices e.g., blood sampling, but may also be assessed by documenting behavior. Physiological health assessments, although powerful, may be stressful for animals, time-consuming and costly, while assessments of behavior can also be time-consuming, subject to bias and suffer from a poorly defined link between behavior and health. However, behavior is recognized as having the potential to code for stress and well-being and could, therefore, be used as an indicator of health, particularly if the process of quantifying behavior could be objective, formalized and streamlined to be time efficient. This study used Daily Diaries (DDs) (motion-sensitive tags containing tri-axial accelerometers and magnetometers), to examine aspects of the behavior of bycaught loggerhead turtles, Caretta caretta in various states of health. Although sample size limited statistical analysis, significant behavioral differences (in terms of activity level and turn rate) were found between "healthy" turtles and those with external injuries to the flippers and carapace. Furthermore, data visualization (spherical plots) clearly showed atypical orientation behavior in individuals suffering gas emboli and intestinal gas, without complex data analysis. Consequently, we propose that the use of motion-sensitive tags could aid diagnosis and inform follow-up treatment, thus facilitating the rehabilitation process. This is particularly relevant given the numerous rehabilitation programs for bycatch sea turtles in operation. In time, tag-derived behavioral biomarkers, TDBBs for health could be established for other species with more complex behavioral repertoires such as cetaceans and pinnipeds which also require rehabilitation and release. Furthermore, motion-sensitive data from animals under human care and wild conspecifics could be compared in order to define a set of objective behavioral states (including activity levels) for numerous species housed in zoos and aquaria and/or wild species to help maximize their welfare. ; We are grateful to Phil Hopkins for help with the tag housings. We would like to thank all the professionals at the Oceanogràfic, especially at the rehabilitation center (ARCA) taking care of the animals, for their efforts and dedication to provide excellent animal care. We are very grateful to all the fishermen contributing to the project as well as to the Valencian Government, especially to the Servicio de Vida Silvestre de la Conselleria d'Agricultura, Medi Ambient, Canvi Climàtic i Desenvolupament Rural de la Generalitat Valenciana. Funding. This research contributes to the CAASE project funded by King Abdullah University of Science and Technology (KAUST) under the KAUST Sensor Initiative. The Fundación Oceanogràfic provided a student bursary for AA and paid the costs to run the rehabilitation facility ARCA were all the work was done.

Abstract Background Understanding what animals do in time and space is important for a range of ecological questions, however accurate estimates of how animals use space is challenging. Within the use of animal-attached tags, radio telemetry (including the Global Positioning System, 'GPS') is typically used to verify an animal's location periodically. Straight lines are typically drawn between these 'Verified Positions' ('VPs') so the interpolation of space-use is limited by the temporal and spatial resolution of the system's measurement. As such, parameters such as route-taken and distance travelled can be poorly represented when using VP systems alone. Dead-reckoning has been suggested as a technique to improve the accuracy and resolution of reconstructed movement paths, whilst maximising battery life of VP systems. This typically involves deriving travel vectors from motion sensor systems and periodically correcting path dimensions for drift with simultaneously deployed VP systems. How often paths should be corrected for drift, however, has remained unclear. Methods and results Here, we review the utility of dead-reckoning across four contrasting model species using different forms of locomotion (the African lion Panthera leo, the red-tailed tropicbird Phaethon rubricauda, the Magellanic penguin Spheniscus magellanicus, and the imperial cormorant Leucocarbo atriceps). Simulations were performed to examine the extent of dead-reckoning error, relative to VPs, as a function of Verified Position correction (VP correction) rate and the effect of this on estimates of distance moved. Dead-reckoning error was greatest for animals travelling within air and water. We demonstrate how sources of measurement error can arise within VP-corrected dead-reckoned tracks and propose advancements to this procedure to maximise dead-reckoning accuracy. Conclusions We review the utility of VP-corrected dead-reckoning according to movement type and consider a range of ecological questions that would benefit from dead-reckoning, primarily concerning animal–barrier interactions and foraging strategies. ; This research contributes to the CAASE project funded by King Abdullah University of Science and Technology (KAUST) under the KAUST Sensor Initiative. Fieldwork in the Kgalagadi Transfrontier Park was supported in part by a Department for Economy Global Challenges Research Fund grant to MS. Fieldwork within the Chubut Province was supported in part by the National Agency for Scientific and Technological Promotion of Argentina (PICT 2017-1996 and PICT 2018-1480), and the Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (16K18617, 16H06541). Fieldwork at Round Island, Mauritius, was supported by the European Research Council under the European Union's Horizon 2020 research and innovation programme grant (715874), awarded to ELCS.