3,212 research outputs found
Dive Deeper Journeys with Moby-Dick
No full textAn easy-to-navigate guide to Herman Melville's epic American novel, Dive Deeper consists of 135 brief chapters, along with Etymology, Extracts, and Epilogue, each keyed to a phrase, issue, image, sensibility or notion in corresponding chapters of the original.Cover -- Table of Contents -- A Note to Readers -- Etymology -- Extracts -- Moby-Dick: Chapters 1 - 135 -- Epilogue -- Acknowledgments -- Credits -- Notes -- Index -- A -- B -- C -- D -- E -- F -- G -- H -- I -- J -- K -- L -- M -- N -- O -- P -- Q -- R -- S -- T -- U -- V -- W -- Y -- ZAn easy-to-navigate guide to Herman Melville's epic American novel, Dive Deeper consists of 135 brief chapters, along with Etymology, Extracts, and Epilogue, each keyed to a phrase, issue, image, sensibility or notion in corresponding chapters of the original.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
The scaling of diving time budgets : insights from an optimality approach
No full textThe authors acknowledge the Natural Environment Research Council for support with this work (grant NER/A/S/2003/00616).Simple scaling arguments suggest that, among air-breathing divers, dive duration should scale approximately with mass to the one-third power. Recent phylogenetic analyses appear to confirm this. The same analyses showed that duration of time spent at the surface between dives has scaling very similar to that of dive duration, with the result that the ratio of dive duration to surface pause duration is approximately mass invariant. This finding runs counter to other arguments found in the diving literature that suggest that surface pause duration should scale more positively with mass, leading to a negative scaling of the dive-pause ratio. We use a published model of optimal time allocation in the dive cycle to show that optimal decisions can predict approximate mass invariance in the dive-pause ratio, especially if metabolism scales approximately with mass to the two-thirds power (as indicated by some recent analyses) and oxygen uptake is assumed to have evolved to supply the body tissues at the required rate. However, emergent scaling rules are sensitive to input parameters, especially to the relationship between the scaling of metabolism and oxygen uptake rate at the surface. Our results illustrate the utility of an optimality approach for developing predictions and identifying key areas for empirical research on the allometry of diving behavior.Peer reviewe
Dive tourism and local communities: active participation or passive impacts? Case studies from Malaysia.
No full textFor many Less Developed Countries international tourism has long been considered a driver for economic development (OECD, 1967). However, tourism has also been heavily criticised for its negative environmental and cultural impacts and significant economic leakages due to the dependence of many host countries on large trans-national corporations (Mowforth and Munt, 2003). Specialist tourism forms such as eco-tourism or small-scale locally owned tourism have been promoted in response to these criticisms,with benefits advocated for local communities, greater cultural awareness by tourists and
more controllable environmental impacts (Weaver, 2001; Scheyvens, 2002; Hampton,2005).
Using local participation approaches, this Working Paper examines dive tourism
as a form of niche tourism and assesses its impacts on local host communities. It investigates whether, or to what extent, active local participation is possible, and how far host communities are merely exposed to ‘passive’ impacts of dive tourism.
The study covered three research locations in Malaysia and revealed that many
aspects of local community life were affected by dive tourism. Besides physical changes such as new infrastructure, the study showed varied economic impacts for local communities through the existence (or lack of)employment/business opportunities, and differing levels of economic linkages, notably the purchase of goods and services between the dive industry and host villages. Local participation varied between locations and a number of obstacles to increased participation were revealed. Furthermore, impacts
on local culture and society were observed as well as a lack of participation in possible cultural productions (handicrafts, performances) by local host communities. As a consequence of the dive industry’s initiatives however, positive educational impacts were noted, especially concerning environmental awareness and English language acquisition
Dive tourism, communities and small islands: lessons from Malaysia and Indonesia
No full textCoastal tourism is growing rapidly across South-East Asia, especially in small islands. Islands and coastal areas face significant issues of how to manage the rapid growth of tourism whilst retaining economic benefits for the local host community. First, the paper sets the context and charts the scale and significance of international dive tourism, especially in less developed countries. The paper draws upon extensive fieldwork in small island destinations in Malaysia and Indonesia and explores how to research this area and the particular practicalities of fieldwork. Next the paper analyses the main socio-economic impacts of dive tourism drawing upon findings published in Haddock-Fraser and Hampton (2012); Daldeniz and Hampton (2013) and Hamzah and Hampton (2013) before introducing new analysis that is 'work in progress.' Finally, the paper concludes by considering lessons for other destinations in South-East Asia learning from success, and helping avoid mistakes being repeated
Fishing for drifts : detecting buoyancy changes of a top marine predator using a step-wise filtering method
No full textThis research was partly funded by a Natural Environment Research Council grant [NE/E018289/1]. Further, a PhD studentship in Marine Biology partially funded by the Natural Environment Research Council [NE/L501852/1] and the University of St Andrews 600th Scholarship supported this work.In southern elephant seals (Mirounga leonina), fasting and foraging related fluctuations in body composition are reflected by buoyancy changes which can be monitored by changes in drift rate. Here, we present an improved knowledge-based method for detecting buoyancy changes from compressed and abstracted dive profiles received through telemetry. We applied this step-wise filtering method to the dive records of 11 southern elephant seals, which identified 0.8% to 2.2% of all dives as drift dives. At the beginning of the migration, all individuals were strongly negatively buoyant. Over the following 75 to 150 days, the buoyancy reached a peak close to or at neutral buoyancy, indicative of a seal’s foraging success. Ground-truthing confirmed that this new knowledge-based method is capable to reliably detect buoyancy changes in the dive records of drift diving species using abstracted dive profiles. This affirms that the abstraction algorithm conveys sufficient detail of the geometric shape of drift dives for them to be identified. It also suggest that using this step-wise filtering method, buoyancy changes could be detected even in old datasets with compressed dive information, for which conventional drift dive classification previously failed.Peer reviewe
Behavioural changes of a long-ranging diver in response to oceanographic conditions
No full textBL 5019 Research project. MRes Environmental BiologyThe development of an animal-borne instrument that can record oceanographic measurements (CTD-SRDL) has enabled the collection of oceanographic data at a scale relevant to the counterpart behavioural data, both in time and 3-dimensional space. This has advanced the potential for studies of the behaviour of deep-diving marine animals and the way in which they respond to their environment, yet the nature of the data delivered by CTD-SRDLs presents substantial analytical challenges and places constraints on its biological interpretation. Behavioural and environmental data, collected using CTD-SRDLs deployed on southern elephant seals (Mirounga leonina) from the South Georgia subpopulation in 2004 and 2005, are analysed for 13 females and 4 males (21,015 dives). Compressed dive profiles are used to classify individual dives into six distinct types based on their 2-dimensional time-depth characteristics using random forest classification. The relationship between dive type and environmental variables, derived from oceanographic data recorded on board the animals, is investigated in the context of regression analysis, employing a multinomial model, as well as independently fitted Generalized Linear Models (GLM) and Generalized Additive Models (GAM) for each dive type. Regression is not found to be an appropriate method for analysing abstracted behavioural dive data, and other methods are suggested. We show that functional specializations can be manifested within a dive type, using square bottom dives (SQ) as an example. The usefulness of dive classification is discussed in the context of behavioural interpretation, and validity of the ecological functions attached to each class. Preliminary analyses are important drivers of further research into improving the interpretability of abstracted behavioural data, and developing efficient, standardized methods for widespread application to this type of data, which is obtained in abundance via satellite telemetry
Changes in dive behaviour during naval sonar exposure in killer whales, long-finned pilot whales, and sperm whales.
No full textAnthropogenic underwater sound in the environment might potentially affect the behavior of marine mammals enough to have an impact on their reproduction and survival. Diving behavior of four killer whales (Orcinus orca), seven long-finned pilot whales (Globicephala melas), and four sperm whales (Physeter macrocephalus) was studied during controlled exposures to naval sonar [low frequency active sonar (LFAS): 1–2 kHz and mid frequency active sonar (MFAS): 6–7 kHz] during three field seasons (2006–2009). Diving behavior was monitored before, during and after sonar exposure using an archival tag placed on the animal with suction cups. The tag recorded the animal's vertical movement, and additional data on horizontal movement and vocalizations were used to determine behavioral modes. Killer whales that were conducting deep dives at sonar onset changed abruptly to shallow diving (ShD) during LFAS, while killer whales conducting deep dives at the onset of MFAS did not alter dive mode. When in ShD mode at sonar onset, killer whales did not change their diving behavior. Pilot and sperm whales performed normal deep dives (NDD) during MFAS exposure. During LFAS exposures, long-finned pilot whales mostly performed fewer deep dives and some sperm whales performed shallower and shorter dives. Acoustic recording data presented previously indicates that deep diving (DD) is associated with feeding. Therefore, the observed changes in dive behavior of the three species could potentially reduce the foraging efficiency of the affected animals.Peer reviewe
Efficient abstracting of dive profiles using a broken-stick model
No full textThis work was supported by SMRU Ltd (now SMRU Marine) in the form of a PhD fellowship (T.P.). Completion of the manuscript was supported by a National Research Foundation Scarce Skills Postdoctoral Fellowship at the University of Cape Town, South Africa (T.P.). The CTD-SRDL data presented in this manuscript were collected as part of a project funded by the Natural Environment Research Council (NERC) grants NE/E018289/1 and NER/D/S/2002/00426.For diving animals, animal-borne sensors are used to collect time-depth information for studying behaviour, ranging patterns and foraging ecology. Often, this information needs to be compressed for storage or transmission. Widely used devices called conductivity-temperature-depth satellite relay data loggers (CTD-SRDLs) sample time and depth at high resolution during a dive and then abstract the time-depth trajectory using a broken-stick model (BSM). This approximation method can summarize efficiently the curvilinear shape of a dive, using a piecewise linear shape with a small, fixed number of vertices, or break points. We present the process of abstracting dives using the BSM and quantify its performance, by measuring the uncertainty associated with the profiles it produces. We develop a method for obtaining a confidence zone and an index for the goodness-of-fit (dive zone index, DZI) for abstracted dive profiles. We validate our results with a case study using dives from elephant seals (Mirounga spp.). We use generalized additive models (GAMs) to determine whether the DZI can be used as a proxy for an absolute measure of fit and investigate the relationship between the DZI and the dive shape. We found a strong correlation between the residual sum of squares (RSS) for the difference between the detailed and abstracted profiles, and the DZI and maximum residual (R4), for dives resulting from CTD-SRDLs (69% deviance explained). On its own, the DZI explained a lower percentage of deviance which was variable for abstracted dives with different numbers of break points. We also found evidence for systematic differences in the DZI for different dive shapes (65% deviance explained). Although the proportional loss of information in the abstraction of time-depth dive profiles by BSM is high, what remains is sufficient to infer goodness-of-fit of the abstracted profile by reversing the abstraction process. Our results suggest that together the DZI and R4 can be used as a proxy for the RSS, and we present the method for obtaining these metrics for BSM-abstracted profiles.Peer reviewe
Developing DIVE, a design-led futures technique for SMEs
No full textFutures techniques have long been used in large enterprises as designerly means to explore the future and guide innovation. In the automotive industry, for instance, the development of concept cars is a technique which has repeatedly proven its value. However, while big companies have broadly embraced futures techniques, small- and medium-sized enterprises(SMEs) have lagged behind in applying them, largely because they are too resourceintensive and poorly suited to the SMEs’ needs and idiosyncrasies. To address this issue, we developed DIVE: Design, Innovation, Vision, and Exploration, a design-led futures technique for SMEs. Its development began with an inquiry into concept cars in the automotive industry and concept products and services in other industries. We then combined the insights derived from these design practices with elements of the existing techniques of critical design and design fiction into the creation of DIVE’s preliminary firstversion, which was then applied and evaluated in two iterations with SMEs, resulting in DIVE’s alpha version. After both iterations in context, it seems that DIVE suits the SMEs because of its compact and inexpensive activities which emphasize making and storytelling. Although the results of these activities might be less flashy than concept cars, these simple prototypes and videos help SMEs internalize and share a clear image of a preferable future, commonly known as vision. Developing DIVE thus helped us explore how design cansupport SMEs in envisioning the future in the context of innovation.Accepted author manuscriptDesign Conceptualization and CommunicationProduct Innovatie Managemen
How man-made interference might cause gas bubble emboli in deep diving whales
No full textRecent cetacean mass strandings in close temporal and spatial association with sonar activity has raised the concern that anthropogenic sound may harm breath-hold diving marine mammals. Necropsy results of the stranded whales have shown evidence of bubbles in the tissues, similar to those in human divers suffering from decompression sickness (DCS). It has been proposed that changes in behavior or physiological responses during diving could increase tissue and blood N2 levels, thereby increasing DCS risk. Dive data recorded from sperm, killer, long-finned pilot, Blainville's beaked and Cuvier's beaked whales before and during exposure to low- (1–2 kHz) and mid- (2–7 kHz) frequency active sonar were used to estimate the changes in blood and tissue N2 tension (PN2). Our objectives were to determine if differences in (1) dive behavior or (2) physiological responses to sonar are plausible risk factors for bubble formation. The theoretical estimates indicate that all species may experience high N2 levels. However, unexpectedly, deep diving generally result in higher end-dive PN2 as compared with shallow diving. In this focused review we focus on three possible explanations: (1) We revisit an old hypothesis that CO2, because of its much higher diffusivity, forms bubble precursors that continue to grow in N2 supersaturated tissues. Such a mechanism would be less dependent on the alveolar collapse depth but affected by elevated levels of CO2 following a burst of activity during sonar exposure. (2) During deep dives, a greater duration of time might be spent at depths where gas exchange continues as compared with shallow dives. The resulting elevated levels of N2 in deep diving whales might also make them more susceptible to anthropogenic disturbances. (3) Extended duration of dives even at depths beyond where the alveoli collapse could result in slow continuous accumulation of N2 in the adipose tissues that eventually becomes a liability.Peer reviewe
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