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Boat
Kinds of Boat Terms modified by Boat Selected AbstractsCOULD YOU TAKE A PICTURE OF MY BOAT, PLEASE?OXFORD JOURNAL OF ARCHAEOLOGY, Issue 4 2008THE USE AND SIGNIFICANCE OF MEDITERRANEAN SHIP REPRESENTATIONS Summary Representations of ships, sailors and seafarers are common in many ancient societies. They were carved, drawn or painted on a great variety of raw materials , stone, wood, metal, textiles and pottery , and can be found in settings such as caves, tombs or royal palaces. Their presence at these sites raises the possibility that these images of maritime life have symbolic or ritual connotations. This paper presents examples of representations of Phoenician and Punic ships from the first millennium BC, in an attempt to understand the role of both their creators and their audiences. These images are subsequently analysed in more detail, focusing on their technical features and their historical contexts. This paper concludes with a consideration of the social and religious aspects of ancient Mediterranean navigation. [source] THE SHORT-TERM BEHAVIORAL REACTIONS OF BOTTLENOSE DOLPHINS TO INTERACTIONS WITH BOATS IN DOUBTFUL SOUND, NEW ZEALANDMARINE MAMMAL SCIENCE, Issue 4 2006David Lusseau Abstract Doubtful Sound is home to one of the southernmost resident populations of bottlenose dolphins (Tursiops sp.). This population regularly interacts with scenic cruises. During these interactions, dolphins tend to horizontally and vertically avoid vessels, especially when the behavior of these vessels is intrusive. This study aimed at understanding the behavioral reactions of individuals to these interactions that lead to the disruption of the school's behavioral state. Observing the behavioral events performed by individuals during an interaction can help define the short-term reactions elicited by the boat presence. I recorded the behavioral events performed by all individuals of focal schools. The frequency of occurrence of all events was compared depending on the presence of vessels, their behavior, and the behavioral state of the focal school. Dolphins tended to perform more side flops while interacting with powerboats, a behavior which may be used as a non-vocal communication tool. Moreover, the movement of dolphins became more erratic during interactions with all types of vessels. These effects increased when the boats were more intrusive while interacting. This study shows that the impact of interaction with boats can be minimized if the vessels respect the guidelines in place. [source] Are We Missing the Boat?CONSERVATION BIOLOGY, Issue 5 2009Collaborative Solutions for North American Fish Wars No abstract is available for this article. [source] Minimal, Intermediate, and Maximum Reconstructions of the Dover BoatINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 2 2006Edward Von der Porten No abstract is available for this article. [source] C20 Carbon Clusters: Fullerene,Boat,Sheet Generation, Mass Selection, Photoelectron CharacterizationCHEMISTRY - A EUROPEAN JOURNAL, Issue 24 2006Horst Prinzbach Prof. Dr. Abstract Electron-impact ionization in a time-of-flight mass spectrometer of C20H0,3Br14,12 probes,secured from C20H20 dodecahedrane by a "brute-force" bromination protocol,provided bromine-free C20H0,2(3) anions in amounts that allowed the clean mass-separation of the hydrogen-free C20, ions and the photoelectron (PE) spectroscopic characterization as C20 fullerene (electron affinity (EA)=2.25±0.03 eV, vibrational progressions of 730±70). The extremely strained C20 fullerene ions surfaced as kinetically rather stable entities (lifetime of at least the total flight time of 0.4 ms); they only very sluggishly expel a C2 unit. The HOMO and LUMO are suggested to be almost degenerate (,E=0.27 eV). The assignment as a fullerene was corroborated by the PE characterization of the C20 bowl (EA=2.17±0.03 eV, vibrational progression of 2060±50 cm,1) analogously generated from C20H10 corannulene (C20H1,3Br9,8 samples) and comparably stable. Highly resolved low-temperature PE spectra of the known C20 ring (EA=2.49±0.03 eV, vibrational progressions 2022±45 and 455±30 cm,1), obtained from graphite, display an admixture of, most probably, a bicyclic isomer (EA=3.40±0.03 eV, vibrational progression 455±30 cm,1). The C20+(,) and C20H2+(,) cluster ions generated from polybrominated perylene (C20H0,2Br12,10) have (most probably) retained the planar perylene-type skeleton (sheet, EA=2.47±0.03 eV, vibrational progressions of 2089±30 and 492±30 cm,1 and EA=2.18±0.03 eV, vibrational progressions of 2105±30 and 468±30 cm,1). [source] The artisanal fishery fleet of the lower AmazonFISHERIES MANAGEMENT & ECOLOGY, Issue 3 2008V. J. ISAAC Abstract, The present study analyses temporal trends in the characteristics of the artisanal fleet landing at ports in the city of Santarém (lower Amazon) from 1993 to 2003. A total of 2714 boats visited the city, accounting for more than 76 000 landings. Of these, 1952 were fishing boats; the others were buyer boats, specialised in the purchase of fish in rural areas for resale in Santarém. The activity involves more than 13 000 fishermen. Fishing boats are made of wood, are on average 11 m long and powered by a 20 hp outboard motor. Boats operate with an average of six to seven fishermen, spending 6 days per trip and catching between 300 and 800 kg of fish. Most variability in yield can be explained by the ice consumed (70%), the number of fishermen trip,1 (19%), fuel consumed (4%) and days spent fishing (3%). The yield changed according to the size, origin and type of boat. Fishing boats coming from more distant locations, in the state of Amazonas, performed better than those from Santarém. Total yield declined slightly during the study period. Mean age of fishing boats and fishing power is increasing. Consumption of ice and fuel by trip, number of fishermen trip,1 and mean days fishing showed positive trends. Financial subsidies from governmental agencies are criticised. Fleet performance and management options are discussed. [source] Boats for Rivers and Mountains: Sources for New Narratives about River Travel?INTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 1 2008Pĺl Nymoen What is a boat? Our notions of what constitutes a good boat are tested when it comes to logboats. They are often considered to be of low status, both technologically and functionally. However, logboats are more interesting than that. This article presents three logboats dated to the Roman era and late Viking age, found in the region of Telemark, Norway. The principal concern is to discuss how notions about prehistoric boats can be made known, challenged and discussed by examining the three boats in the context of the rivers and lakes in which they were most probably used. © 2007 Author [source] The Re-Assessment and Reconstruction of Excavated BoatsINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 2 2007Seán McGrail In response to papers by John Coates and by Owain Roberts, the author re-evaluates mid- to late-20th-century reconstruction drawings and models of prehistoric sewn-plank boats Ferriby 1 and Brigg 2. He concludes that an impartial and informed group should re-examine all surviving evidence for these boats and then build a small-scale ,as-found' model of each one. After being subjected to criticism, these models could become the basis for generally-agreed reconstruction models of the original form and structure of these two boats. A similar process would be the best way ahead for the Dover sewn-plank boat. © 2007 The Author [source] Ancient Boats, Boat Timbers, and Locked Mortise-and-Tenon Joints from Bronze/Iron-Age Northern VietnamINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 1 2007Peter Bellwood This paper describes two nautical discoveries buried c.2000 years ago in the Red River alluvial plain, northern Vietnam. One is part of a logboat with a series of empty mortise and locking-peg holes for plank attachment using loose rectangular tenons. The other, from an infant mortuary house, is a series of re-used 4-m-long timbers with exactly the same locked mortise-and-tenon technology. Both finds are interpreted as having belonged to river-boats like those shown on the sides of Heger 1 (Dong Son) bronze drums. Potentially-related technologies from the Mediterranean and China are also discussed. © 2006 The Authors [source] AFRICA,EUROPE: Migrant Boats Sink off Libyan CoastAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 3 2009Article first published online: 1 MAY 200 No abstract is available for this article. [source] Configuration, conformation and crystal structure of rabdosianin bCRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2005Bao Lin Li Abstract Rabdosianin B, 7,20-epoxy-7,-hydroxy-1,,6,,11,,15,-tetraacetoxy- ent -kaur-16-ene, C28H38O10, was the first isolated from Isodon henryi. It consists of three six-membered rings A, B, C and one five-membered ring D. The fused-ring system A, B and C are in chair, boat and chair conformations, respectively, and ring D is in an envelope conformation, on the basis of NMR and X-ray diffraction analysis. The crystal of rabdosianin B is in orthorhombic crystal system with space group P212121, lattice constants: a = 9.969(1) Ĺ, b = 15.400(3) Ĺ, and c = 17.624(3) Ĺ, Z = 4. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Spatial distribution and environmental correlates of Australian snubfin and Indo-Pacific humpback dolphinsECOGRAPHY, Issue 3 2006Guido J. Parra We present data on the spatial distribution of Australian snubfin and humpback dolphins using boat-based line transect surveys in three adjacent bays located in the Far Northern Section of the Great Barrier Reef Marine Park, northeast Queensland. We used Geographic Information Systems (GIS), and both randomization and Mantel tests to examine the relationship between the spatial distribution of the dolphins and three simple, readily quantified, environmental variables: distance to land, distance to river mouth, and water depth. Mantel tests allowed us to make clear inferences about the correlation of the species' distributions with environmental variables, while taking into account spatial autocorrelation and intercorrelation among variables. Randomization tests indicated snubfin and humpback dolphins occur closer to land than would be expected at random. Two-sample randomization tests indicated snubfin dolphins were found closer to river mouths than were humpback dolphins. Taking spatial autocorrelation into account, Mantel tests indicated all environmental variables were correlated with the spatial distribution of snubfin and humpback dolphins. Interspecific differences in spatial distribution appeared to be related to proximity to river mouths. Preference by snubfin and humpback dolphins for nearshore, estuarine waters is likely related to the productivity of these tropical coastal areas. This spatial analysis suggests that existing protected areas in this region may not include the most critical habitats for snubfin and humpback dolphins. The techniques used here shown relationships between the spatial distribution of the dolphins and environmental features that should facilitate their management and conservation. [source] Parasites lost , do invaders miss the boat or drown on arrival?ECOLOGY LETTERS, Issue 4 2010Catriona J. MacLeod Ecology Letters (2010) 13: 516,527 Abstract Host species that colonize new regions often lose parasite species. Using population arrival and establishment data for New Zealand's introduced bird species and their ectoparasitic chewing lice species, we test the relative importance of different processes and mechanisms in causing parasite species loss. Few lice failed to arrive in New Zealand with their hosts due to being missed by chance in the sample of hosts from the original population (missing the boat). Rather, most lice were absent because their hosts or the parasite themselves failed to establish populations in their new environment. Given they arrived and their host established, parasite persistence was more strongly related to factors associated with transmission efficiency (number of host individuals introduced, host body size, host sociality and parasite suborder) than parasite propagule pressure and aggregation. Such insights into parasite success are invaluable to both understanding and managing their impact. [source] What is the Chance of Yuan Revaluation?ECONOMIC OUTLOOK, Issue 1 2003Vanessa Rossi From a Chinese perspective, chances of any change in the Yuan exchange rate look pretty slim. If you were an official in Beijing, would you stick your neck out even recommending this idea? If the status quo looks fairly acceptable, and it is ,stability oriented' (a very Chinese preference), why go rocking the boat? You certainly do not make any changes just because Japan or the US tell you to. And financial markets are not that persuasive , after all they wanted a devaluation only a short while ago. In this article, Vanessa Rossi and Simon Knapp assess the likelihood of a Yuan revaluation and its implications for the economic outlook. [source] Omnidirectional multibeam sonar monitoring: applications in fisheries scienceFISH AND FISHERIES, Issue 3 2006Patrice Brehmer Abstract Data exploitation, acquired by medium-frequency omnidirectional multibeam sonar, enables original studies in fisheries research but is seldom used despite the fact that such equipment is found on most fishing vessels and a number of research vessels. This is the only system for real-time monitoring of fish schools within a horizontal omnidirectional plane about a vessel or a buoy. Between 1996 and 2001, we used two standard omnidirectional sonars and developed new methodologies for exploiting their specific acoustic data according to two main sampling schemes: ,prospecting', including fishing and searching operations, and ,drifting', as with an instrumental buoy system or aboard a stationary vessel. We present a complete method for continuous data acquisition from aboard a research vessel or commercial boat, with automated data extraction by picture analysis and a data processing method. Two cases of data analysis are considered: the first on a school-by-school basis, the ,single school' mode; the second taking into account all fish schools detected within the sonar sampling volume, the ,cluster' mode. Elementary sonar information is divided into five categories that comprise 24 survey and sonar parameters and 55 school, cluster and fisher behaviour descriptors. We review the applications of these categories and discuss perspectives for their use in fisheries science. If the sonar system enables the evaluation of the effects of vessel avoidance on fish school biomass assessment, no accurate abundance estimate can be provided by a simple sonar echo-integration process. Omnidirectional sonar data can be used to analyse collectively the fish schools' swimming speed, kinematics in terms of diffusion and migration, aggregative dynamics as school splitting and merging indexes, spatial characteristics of clusters such as school density, 2D structure and fisher behaviour. The prospect of integrating such data into a fish school database, including multifrequency echo-sounder and lateral multibeam (3D) sonar data combined with a species recognition method, will enable a complete view of fish school behaviour and consequently the adoption of accurate fisheries management methods. [source] The artisanal fishery fleet of the lower AmazonFISHERIES MANAGEMENT & ECOLOGY, Issue 3 2008V. J. ISAAC Abstract, The present study analyses temporal trends in the characteristics of the artisanal fleet landing at ports in the city of Santarém (lower Amazon) from 1993 to 2003. A total of 2714 boats visited the city, accounting for more than 76 000 landings. Of these, 1952 were fishing boats; the others were buyer boats, specialised in the purchase of fish in rural areas for resale in Santarém. The activity involves more than 13 000 fishermen. Fishing boats are made of wood, are on average 11 m long and powered by a 20 hp outboard motor. Boats operate with an average of six to seven fishermen, spending 6 days per trip and catching between 300 and 800 kg of fish. Most variability in yield can be explained by the ice consumed (70%), the number of fishermen trip,1 (19%), fuel consumed (4%) and days spent fishing (3%). The yield changed according to the size, origin and type of boat. Fishing boats coming from more distant locations, in the state of Amazonas, performed better than those from Santarém. Total yield declined slightly during the study period. Mean age of fishing boats and fishing power is increasing. Consumption of ice and fuel by trip, number of fishermen trip,1 and mean days fishing showed positive trends. Financial subsidies from governmental agencies are criticised. Fleet performance and management options are discussed. [source] Synthesis and conformational study of P -heterocyclic androst-5-ene derivativesHETEROATOM CHEMISTRY, Issue 1 2008Éva Frank The reactions of (20R)-3,-acetoxy-21-hydroxymethylpregn-5-en-20-ol (2) and (20R)-3,-acetoxypregn-5-ene-20,21-diol (11) with phenylphosphonic dichloride 3 and aryl dichlorophosphates 4,6 afforded novel types of P -heterocyclic androst-5-ene derivatives 7,10 and 12 as epimeric pairs. The diastereomers were separated by column chromatography and were characterized by NMR spectroscopy. Estimation of the stereostructures of the corresponding epimers by B3LYP/631G(d) DFT ab initio calculations suggested that the six-membered hetero ring in compounds 7b and 8a,10a adopts predominantly a chair conformation, with the P -substituents in their preferred orientation. The cyclic phosphonate moiety in 7a or 8b,10b, however, seems to exist as an equilibrium mixture of chair,distorted- boat or chair,chair forms. The theoretical calculations indicate that the conformational equilibrium is shifted toward the distorted- boat conformer for 7a, with a pseudoequatorial P -phenyl substituent, whereas for 8b,10b the chair conformer with an equatorial P -phenoxy group predominates. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:7,14, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20372 [source] Measuring thaw depth beneath peat-lined arctic streams using ground-penetrating radarHYDROLOGICAL PROCESSES, Issue 14 2005John H. Bradford Abstract In arctic streams, depth of thaw beneath the stream channel is likely a significant parameter controlling hyporheic zone hydrology and biogeochemical cycling. As part of an interdisciplinary study of this system, we conducted a field investigation to test the effectiveness of imaging substream permafrost using ground-penetrating radar (GPR). We investigated three sites characterized by low-energy water flow, organic material lining the streambeds, and water depths ranging from 0·2 to 2 m. We acquired data using a 200 MHz pulsed radar system with the antennas mounted in the bottom of a small rubber boat that was pulled across the stream while triggering the radar at a constant rate. We achieved excellent results at all three sites, with a clear continuous image of the permafrost boundary both peripheral to and beneath the stream. Our results demonstrate that GPR can be an effective tool for measuring substream thaw depth. Copyright © 2005 John Wiley & Sons, Ltd. [source] An Early Bronze Age Logboat from Degersee, Southern GermanyINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 1 2009Martin Mainberger In 2004 the remains of a logboat were discovered in Degersee, a small lake near Lake Constance, southern Germany. Dating to the beginning of the 2nd millennium BC, it is an important find from a period with scarce archaeological evidence and only a few previously-known logboats. The vessel was situated in lake sediment and documented in situ. Our investigations can be linked to palaeo-environmental studies carried out at Degersee and adjacent lakes, and to palaeo-climatic research in the northern Alpine region. After investigation by underwater archaeologists the boat was moved to a sheltered place in deeper water. © 2008 The Author [source] Boats for Rivers and Mountains: Sources for New Narratives about River Travel?INTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 1 2008Pĺl Nymoen What is a boat? Our notions of what constitutes a good boat are tested when it comes to logboats. They are often considered to be of low status, both technologically and functionally. However, logboats are more interesting than that. This article presents three logboats dated to the Roman era and late Viking age, found in the region of Telemark, Norway. The principal concern is to discuss how notions about prehistoric boats can be made known, challenged and discussed by examining the three boats in the context of the rivers and lakes in which they were most probably used. © 2007 Author [source] Rock Art: A Potential Source of Information about Past Maritime Technology in the South-East Asia-Pacific RegionINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 2 2007Peter V. Lape It is possible that most or all boats and rig-types used in prehistoric times in the South-East Asia-Pacific region have completely disappeared from the record, and that those recorded by Europeans in the 17th century may have been relatively recent innovations. The purpose of this paper is to introduce to the literature a new source of information on ancient boat and rig designs. This source is the information encoded in rock-art depictions of watercraft. This paper provides a technical appraisal of 18 images of watercraft from the Tutuala region of East Timor. © 2007 The Authors [source] The Re-Assessment and Reconstruction of Excavated BoatsINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 2 2007Seán McGrail In response to papers by John Coates and by Owain Roberts, the author re-evaluates mid- to late-20th-century reconstruction drawings and models of prehistoric sewn-plank boats Ferriby 1 and Brigg 2. He concludes that an impartial and informed group should re-examine all surviving evidence for these boats and then build a small-scale ,as-found' model of each one. After being subjected to criticism, these models could become the basis for generally-agreed reconstruction models of the original form and structure of these two boats. A similar process would be the best way ahead for the Dover sewn-plank boat. © 2007 The Author [source] The Thaikkal-Kadakkarappally Boat: an Archaeological Example of Medieval Shipbuilding in the Western Indian OceanINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 2 2004Victoria Tomalin Recent excavations at Kadakkarappally in Kerala, south-west India, have unearthed the remains of an iron-fastened boat, believed to predate the earliest known records for the use of iron in South Asian boatbuilding. The design departs significantly from the traditional view of Indian watercraft, although the use of locally available timber and the suitability of the design for use in the backwaters that characterise the region suggest that it was built and used in India. This is the first excavation of its type to take place in Kerala and contradicts the belief, widely held in Kerala, that the survival of organic remains has been negated by the tropical climate of the region. © 2004 The Nautical Archaeology Society [source] Cover Picture: J. Basic Microbiol.JOURNAL OF BASIC MICROBIOLOGY, Issue 2 20092/200 Morphological diversity among Anabaena isolates from major agro-ecologies of India, depicting the heterogeneity in shape, size and colour of cells and trichomes. Shown are Anabaena type strain, coiled filaments (A. circinalis), pointed end cell (A. spiroides), double heterocysts (A. iyengarii), heterocysts (A. aphanizomenoides), large, oval and boat shaped akinetes (A. flos-aquae, A. anomala, A. naviculoides), in-situ germination of akinetes (A. sphaerica) and a series of akinetes (A. variabilis var. ellipsospora). Scale bar = 40 ,m (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Geographic miss in radiation oncology: Have we missed the boat?JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 5 2009S Everitt [source] 81 Recent introduction of polysiphonia morrowii (ceramiales, rhodophyta) to punta arenas, chileJOURNAL OF PHYCOLOGY, Issue 2003M.S. Kim Polysiphonia morrowii (Rhodomelaceae, Rhodophyta) is abundant intertidally in spring in the Northwest Pacific. The species occurs in a large part of the North Sea and in Thau Lagoon, France, showing disjointed distributions, where the alga has been probably introduced recently. Using plastid protein-coding rbcL sequence data from specimens of P. morrowii and putatively related taxa, collected in Korea, Japan and Far-east Russia, and Chile, we tested the taxonomic position of each taxon. Pairwise divergence and topology of the sequences indicate that the Chilean taxon was identical to P. morrowii and was clearly separated from other related taxa from Chile. The results suggest that P. morrowii is recently anthropogenically introduced from the Northwest Pacific to Chile by boat or by transport with aquacultured organisms. Detailed observations of field-collected material will probably enable a more realistic evaluation of distribution of P. morrowii to be made in the Pacific Ocean. [source] Design and field methods for sighting surveys of cetaceans in coastal and riverine habitatsMAMMAL REVIEW, Issue 1 2008STEVE DAWSON ABSTRACT 1Dolphins and porpoises in coastal and/or riverine habitats face serious conservation threats, yet surveys of their abundance are often especially difficult due to the challenges imposed by the habitats. Because many of these species occur in developing countries, lack of resources imposes a further set of challenges. 2We offer advice on designing and conducting line-transect surveys with a focus on sound, practical, design rather than analytical sophistication, and we attempt, where possible, to offer simple, inexpensive solutions. 3We guide the reader through the questions of what kind of survey should be done, whether by boat or aircraft, and we discuss ways to avoid bias and increase precision. 4Our treatment of field methods focuses especially on robust, but low-cost, approaches. We provide two case studies to illustrate the implementation of these ideas. [source] The Impact of Human Recreational Activities in Marine Protected Areas: What Lessons Should Be Learnt in the Mediterranean Sea?MARINE ECOLOGY, Issue 2002Marco Milazzo Abstract. The aesthetic appeal of marine reserves and the facilities provided, together with the increased public awareness of nature, all contribute to creating massive tourism in MPAs. Human activities are being changed inside MPAs in two ways: humans as top predators are generally being removed, but in turn they could come back at great numbers as visitors. Many authors have studied the impact of visitors, and the results highlight that the consequences can be very substantial and may represent a severe threat to the overall diversity of marine communities. To date, the documented effects of human recreational activities on natural communities are restricted to assessing the consequences of trampling over intertidal and upper infralittoral areas, boat anchoring in seagrass meadows and tropical reefs, or SCUB A-diving. In this paper we review the available literature world-wide on the effects of human recreational activities in marine communities. The objective is to address the extent of these impacts and to highlight the gaps of knowledge to be filled in order to optimise decision making on research, monitoring, and management of Mediterranean MPAs. A specific plan for managing tourism use in each Mediterranean MPA should be designated. These strategies should be implemented through education, training, and changes in legislation and policy. [source] INCREASED AVOIDANCE OF SWIMMERS BY WILD BOTTLENOSE DOLPHINS (TURSIOPS TRUNCATUS) DUE TO LONG-TERM EXPOSURE TO SWIM-WITH-DOLPHIN TOURISMMARINE MAMMAL SCIENCE, Issue 4 2001Rochelle Constantine Abstract The responses of wild, non-provisioned bottlenose dolphins (Tursiops truncatus) to swim attempts from commercial swim-with-dolphin tour boats were systematically observed during two research periods: 1994,1995 and 1997,1998. A total of 255 groups of dolphins was encountered during boat-based surveys and 36% (n= 93) were exposed to at least one swim attempt. The operators' success with swim attempts, defined as at least one dolphin milling within 5 m of at least one swimmer, decreased from 48% in 1994,1995 to 34% in 1997,1998, and avoidance responses to swimmers increased from 22% to 31%. Dolphin response was found to vary according to swimmer placement. The greatest increase in avoidance occurred when swimmers were placed in the dolphins' path of travel. Based on sighting records of 266 individually identified dolphins, it was estimated that an average dolphin was exposed to 31 swim attempts per year. This level of exposure suggests that individual dolphins have, with cumulative experience, become sensitized to swim attempts. When a swim attempt was successful, on average it involved 19% of the group. Age-class differences in interaction rates showed that juveniles were significantly more likely to interact with swimmers than adults. This study highlights the importance of longitudinal studies in evaluating human impact and suggests the urgent need for similar studies of potential human impact on other toothed cetaceans. [source] SIMULATING THE WESTERN SEAWAYSOXFORD JOURNAL OF ARCHAEOLOGY, Issue 4 2009RICHARD CALLAGHAN Summary Recent debates on the introduction of Neolithic features to Britain have emphasized the role of the western maritime routes and the possibility of direct or indirect connections from Brittany to Ireland and Argyll. Here we present the results of simulation modelling of maritime voyaging by paddled or sail-powered boat, indicating the likely lengths of the journeys that would have been required. The issue of direct travel vs. short crossings and coasting is explored, and the implications for specific connections, such as those posited to account for cattle remains in a pre-Neolithic context in Ireland, are considered. [source] | |||||||||||||||||||||||||||||||