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Whales
Kinds of Whales Terms modified by Whales Selected AbstractsA NORTHEAST PACIFIC OFFSHORE KILLER WHALE (ORCINUS ORCA) FEEDING ON A PACIFIC HALIBUT (HIPPOGLOSSUS STENOLEPIS)MARINE MAMMAL SCIENCE, Issue 1 2006Iain M. Jones No abstract is available for this article. [source] SEASONAL OCCURRENCE OF SPERM WHALE (PHYSETER MACROCEPHALUS) SOUNDS IN THE GULF OF ALASKA, 1999,2001MARINE MAMMAL SCIENCE, Issue 1 2004David K. Mellinger Abstract An acoustic survey for sperm whales was conducted in the Gulf of Alaska. Six autonomous hydrophones continuously recorded sound signals below 500 Hz from October 1999 to May 2001. After recovery, recordings were processed using an automatic process to detect usual clicks of sperm whales. The detection algorithm equalized background noise, summed the data in a frequency band, and then used autocorrelation to detect the whales' highly regular clicks. Detections were checked manually, revealing that 98% of detections did contain clicks. Results indicate that sperm whales are present in the Gulf of Alaska year-round; this result extends what is known from whaling data, which were gathered principally in summer. Sperm whales were more common in summer than winter by a factor of roughly two, and occurred less often at the westernmost site surveyed (52°N, 157°W) than elsewhere in the Gulf. This is the first study of sperm whales based exclusively on remote acoustic sensing. This methodology is feasible because sperm whale clicks extend to frequencies (,100 Hz) low enough to be recorded by low-sample-rate instruments that operate continuously, and because the detection algorithm has a low false-detection rate. The methodology may be replicated to facilitate comparisons between different time periods and geographic regions. [source] KILLER WHALE (ORCINUS ORCA) DISTRIBUTION AND ABUNDANCE IN THE CENTRAL AND SOUTHEASTERN BERING SEA, JULY 1999 AND JUNE 2000MARINE MAMMAL SCIENCE, Issue 3 2002Janice M. Waite [source] CHARACTERIZATION OF BEAKED WHALE (ZIPHIIDAE) AND SPERM WHALE (PHYSETER MACROCEPHALUS) SUMMER HABITAT IN SHELF-EDGE AND DEEPER WATERS OFF THE NORTHEAST U. S.MARINE MAMMAL SCIENCE, Issue 4 2001G. T. Waring Abstract Sperm whales (Physeter macrocephalus) and beaked whales (Mesoplodon spp. and Ziphius cavirostris) are deep-diving cetaceans that frequent shelf-edge and Gulf Stream waters off the northeast U. S. coast. Sighting data collected during seven summer (1990, 1991, 1993, and 1995,1998) shipboard surveys were analyzed using a geographic information system to determine habitat use based on bathymetric and oceanographic features. Although sighting rates were lower for beaked whales, both taxa occupied similar habitats. Beaked whales were concentrated at the colder shelf edge, whereas sperm whales were associated with warmer off-shelf water. Mean sighting rates for both taxa were higher in canyon features, but only beaked whale sighting rates were significantly different between canyon and non-canyon habitat (Wilcoxon signed rank test P= 0.007). Within the shared habitat, the two taxa were separated at fine-scale based on oceanographic features. [source] SWIMMING SPEEDS OF SINGING AND NON-SINGING HUMPBACK WHALES DURING MIGRATIONMARINE MAMMAL SCIENCE, Issue 3 2007Michael J. Noad Abstract Limited data exist on swimming speeds of humpback whales (Megaptera novaeangliae) and none on swimming speeds of singing whales during migration. We tracked humpback whales visually and acoustically during migration from the breeding grounds past our study site on the east coast of Australia (latitude 26°28,S). The mean swimming speed for whales while singing was 2.5 km/h, significantly less than for non-singing whales with a mean of 4.0 km/h but significantly greater than the mean of 1.6 km/h observed for singing whales on the Hawaiian breeding grounds. Between song sessions, there was no significant difference in speeds between whales that had been singing and other whales. Migration speeds were less for whales while singing but increased during the season. Although humpback whales can swim rapidly while singing (maximum observed 15.6 km/h), they generally do not do so, even during migration. Slower migration by singers would delay their return to the polar feeding areas and may be costly, but may be a strategy to provide access to more females. [source] SPITSBERGEN BOWHEAD WHALES REVISITEDMARINE MAMMAL SCIENCE, Issue 3 2007Øystein Wiig [source] DOES INTENSE SHIP NOISE DISRUPT FORAGING IN DEEP-DIVING CUVIER'S BEAKED WHALES (ZIPHIUS CAVIROSTRIS)?MARINE MAMMAL SCIENCE, Issue 3 2006Natacha Aguilar Soto First page of article [source] KILLER WHALE ATTACKS ON MINKE WHALES: PREY CAPTURE AND ANTIPREDATOR TACTICSMARINE MAMMAL SCIENCE, Issue 4 2005John K. B. Ford Abstract We describe nine incidents of predation or attempted predation of minke whales (Balaenoptera acutorostrata) by mammal-hunting "transient" killer whales (Orcinus orca) in coastal waters of British Columbia, Washington, and southeastern Alaska. Pursuits of minke whales were characterized by prolonged chases on a straight heading at velocities of 15,30 km/h. In four of the nine cases the adultsized minke whale gradually outdistanced the killer whales, which abandoned the high-speed pursuit after 0.5,1 h. In one case the minke beached itself and died. Four attacks were successful. In one instance a subadult minke was killed in open water following a chase. In two cases the fleeing minke entered a confined bay and was killed by the killer whales. One adult minke was taken after apparently attempting to seek cover beside a large sailboat. Minke whales made no attempt to physically defend themselves and were killed by repeated ramming or by asphyxiation. Although killer whales are capable of sprinting speeds greater than those of minke whales, it appears that adult minkes can maintain higher sustained speeds and evade capture if sufficient space for an extended escape trajectory is available. Successful predation of minke whales in coastal waters is rare compared to pinnipeds and small cetaceans, the main prey of transient killer whales. [source] ENVIRONMENTAL FACTORS INFLUENCING THE DISTRIBUTION OF SOUTHERN RIGHT WHALES (EUBALAENA AUSTRALIS) ON THE SOUTH COAST OF SOUTH AFRICA I: BROAD SCALE PATTERNSMARINE MAMMAL SCIENCE, Issue 3 2004Simon H. Elwen Abstract Aerial surveys over the last 32 yr have shown that the distribution of southern right whales Eubalaena australis along the south coast of South Africa is markedly discontinuous, but highly predictable. A GIS was used at a variety of scales to investigate whether this pattern was related to environmental characteristics. Whale distribution was analyzed as density per 20-min bin of longitude over two temporal and spatial scales, namely 15 bins for 32 yr, and a wider scale but shorter time period, 23 bins for 19 yr, as well as using three years of GPS accuracy data (15 bins) for finer scale analysis. Environmental factors tested were depth, distance from shore, sea floor slope, protection from swell, protection from wind, and shore type. The majority of whales were concentrated in areas that provided reasonable protection from open ocean swell and seasonal winds, and had sedimentary floors with gentle slopes. They generally avoided exposed rocky shorelines. Cow-calf pairs were found significantly closer to shore and in shallower water than unaccompanied whales, particularly off sandy beaches. Habitat choice at this time of year may be related both to energy conservation for calves and lactating females (calm sea conditions) and to protection of the new-born. [source] ENVIRONMENTAL FACTORS INFLUENCING THE DISTRIBUTION OF SOUTHERN RIGHT WHALES (EUBALAENA AUSTRALIS) ON THE SOUTH COAST OF SOUTH AFRICA II: WITHIN BAY DISTRIBUTIONMARINE MAMMAL SCIENCE, Issue 3 2004Simon H. Elwen Abstract Environmental factors are thought to strongly influence the distribution and predictability of the coastal distribution of southern right whales (Eubalaena australis) off South Africa. Preferred habitat had generally shallow sloping sedimentary floors and was characteristically protected from open ocean swell and prevalent seasonal winds. This study investigated whether habitat choices at smaller scales (within bays) were similar. Fine scale distribution patterns (GPS) from three years' surveys (1997, 1999, 2000) were analyzed separately within the three main concentration areas St Sebastian Bay, De Hoop, and Walker Bay (containing ,73% of cow-calf pairs and ,49% of unaccompanied adults in the whole survey region). Whale density at this scale of within particular bays did not correlate well with predicted variables, but Chi-squared analysis strongly supported results at broader scales, in all bays. Post-hoc"choice" tests between similar areas differing in only one variable revealed that cow-calves preferred (presumed) sandy substrates and especially protection from swell. The strength and predictability of preferences shown at fine scale (where individual movement and weather variability could have great influence) provide strong support for findings at larger scales and emphasize the importance of environmental factors in the habitat choice of wintering right whales. [source] GRAY WHALES WITH LOSS OF FLUKES ADAPT AND SURVIVEMARINE MAMMAL SCIENCE, Issue 2 2004J. Urbán R. [source] SIZE-AND AGE-CLASS SEGREGATION OF BOWHEAD WHALES SUMMERING IN NORTHERN FOXE BASIN: A PHOTOGRAMMETRIC ANALYSISMARINE MAMMAL SCIENCE, Issue 2 2003Susan E. Cosens Abstract To determine whether Hudson Bay-Foxe Basin bowhead whales segregate on the basis of age, whales summering in northern Foxe Basin, were aerially photographed in August of 1996, 1997, and 1998. Image lengths on either the negatives or contact prints were measured and total body lengths were estimated. In all three years the majority of whales photographed were ,13.5 m long. Calves and juveniles made up 89.3%, 96.6%, and 79.3% of the total number of measured whales in 1996 (n = 28), 1997 (n = 30) and 1998 (n = 29) respectively. The number of bowheads >13.5 m, the approximate size at which females reach sexual maturity, that were photographed was directly proportional to the number of calves photographed. Our results indicate that northern Foxe Basin bowheads are part of a more widely distributed stock. Adult males and resting adult females apparently summer in another part of the range, probably northwestern Hudson Bay. Northern Foxe Basin appears to be used as a summer feeding area by cows with young-of-the-year calves and by juveniles. [source] THREE MASS STRANDINGS OF SPERM WHALES (PHYSETER MACROCEPHALUS) IN SOUTHERN AUSTRALIAN WATERSMARINE MAMMAL SCIENCE, Issue 3 2002Karen Evans Abstract One hundred and fifteen sperm whales (97 female, 15 male, 3 unknown sex) were involved in three mass stranding events during the month of February 1998 along the west and northwest coastlines of Tasmania, Australia. Sixty-six of these whales stranded at Ocean Beach, Strahan; 35 at Greens Beach, Marrawah; and 11 at Black River Beach, Stanley. The remaining whales stranded singly along the coastline. Three mass strandings of this species in such close temporal proximity have not been reported in this area before, and this is the first time that data have been comprehensively collected from complete or near-complete groups of sperm whales from Tasmanian waters. Adult females dominated the three stranding groups. Total lengths ranged from 417 to 1,200 cm and ages ranged from 0.75 to 64 yr. Four females were lactating and four fetuses were found amongst the groups. Stomach contents were dominated by pelagic cephalopods. [source] KILLER WHALE PREDATION ON SPERM WHALES: OBSERVATIONS AND IMPLICATIONSMARINE MAMMAL SCIENCE, Issue 3 2001Robert L. Pitman Abstract In October 1997 we observed a herd of approximately 35 killer whales (Orcinus orca) attack a pod of nine sperm whales (Physeter macrocephalus) 130 km off the coast of central California. During the four hours we watched, adult female killer whales, including some with calves, attacked in waves of four to five animals in what was apparently a "wound and withdraw" strategy. Adult male killer whales stood by until the very end when one charged in and quickly killed a seriously wounded sperm whale that had been separated from the group. The sperm whales appeared largely helpless: their main defensive behavior was the formation of a rosette ("marguerite"-heads together, tails out). When the killer whales were successful in pulling an individual out of the rosette, one or two sperm whales exposed themselves to increased attack by leaving the rosette, flanking the isolated individual, and leading it back into the formation. Despite these efforts, one sperm whale was killed and eaten and the rest were seriously, perhaps mortally, wounded. We also present details of two other encounters between sperm whales and killer whales that we observed. Although sperm whales, because of various behavioral and morphological adaptations, were previously thought to be immune to predation, our observations clearly establish their vulnerability to killer whales. We suggest that killer whale predation has potentially been an important, and underrated, selective factor in the evolution of sperm whale ecology, influencing perhaps the development of their complex social behavior and at-sea distribution patterns. [source] COLLISIONS BETWEEN SHIPS AND WHALESMARINE MAMMAL SCIENCE, Issue 1 2001David W. Laist Abstract Although collisions with motorized ships are a recognized source of whale mortality, little has been done to compile information on the frequency of their occurrence or contributing factors. We searched historical records and computerized stranding databases for evidence of ship strikes involving great whales (i. e., baleen whales and the sperm whale). Historical records suggest that ship strikes fatal to whales first occurred late in the 1800s as ships began to reach speeds of 13-15 kn, remained infrequent until about 1950, and then increased during the 1950s-1970s as the number and speed of ships increased. Of 11 species known to be hit by ships, fin whales (Balaenoptera physalus) are struck most frequently; right whales (Eubalaena glacialis and E. australis), humpback whales (Megaptera novaeangliae), sperm whales (Physeter catodon), and gray whales (Escbricbtius robustus) are hit commonly. In some areas, one-third of all fin whale and right whale strandings appear to involve ship strikes. To assess contributing factors, we compiled descriptions of 58 collisions. They indicate that all sizes and types of vessels can hit whales; most lethal or severe injuries are caused by ships 80 m or longer; whales usually are not seen beforehand or are seen too late to be avoided; and most lethal or severe injuries involve ships travelling 14 kn or faster. Ship strikes can significantly affect small populations of whales, such as northern right whales in the western North Atlantic. In areas where special caution is needed to avoid such events, measures to reduce the vessel speed below 14 kn may be beneficial. [source] PHOTOGRAPHIC IDENTIFICATION OF NORTHERN BOTTLENOSE WHALES (HYPEROODON AMPULLATUS): SOURCES OF HETEROGENEITY FROM NATURAL MARKSMARINE MAMMAL SCIENCE, Issue 1 2001Shannon Gowans Abstract The use of natural marks in capture-recapture studies can lead to unequal capture probabilities. This paper examined a catalog of northern bottlenose whale (Hyperoodon ampullatus) photographs from the Gully, Nova Scotia, to identify potential sources of heterogeneity. This information can be used to select appropriate individuals and photographs to include in analyses. Individual northern bottlenose whales were sufficiently marked to uniquely identify individuals (x,= 14.5 marks/individual; range 1-67), but not all mark types persisted over time. Reliable marks were defined as mark types that were not lost over the nine-yeat study period (notches, back indentation, and mottled patches). Individuals were considered reliably marked if they possessed at least one back indentation or mottled patch (located within one dorsal fin width, at the base of the dorsal fin) or a notch on the dorsal fin. Sixty-six percent (SE = 5%) of the population were reliably marked. Longterm analyses (months to years) should use only reliably marked individuals, and the results scaled to account for the rest of the population. Our results also showed that photographic quality affected an observer's ability to identify individuals. For this catalog, quantitative analysis indicated only photographs of Q , 4 (on a 6-point scale with 6 representing the highest quality) should be included in mark-recapture analyses sensitive to heterogeneity. [source] Detecting the impact of oceano-climatic changes on marine ecosystems using a multivariate index: The case of the Bay of Biscay (North Atlantic-European Ocean)GLOBAL CHANGE BIOLOGY, Issue 1 2008GEORGES HEMERY Abstract Large-scale univariate climate indices (such as NAO) are thought to outperform local weather variables in the explanation of trends in animal numbers but are not always suitable to describe regional scale patterns. We advocate the use of a Multivariate Oceanic and Climatic index (MOCI), derived from ,synthetic' and independent variables from a linear combination of the total initial variables objectively obtained from Principal Component Analysis. We test the efficacy of the index using long-term data from marine animal populations. The study area is the southern half of the Bay of Biscay (43°,47°N; western Europe). Between 1974 and 2000 we monitored cetaceans and seabirds along 131000 standardized line transects from ships. Fish abundance was derived from commercial fishery landings. We used 44 initial variables describing the oceanic and atmospheric conditions and characterizing the four annual seasons in the Bay of Biscay. The first principal component of our MOCI is called the South Biscay Climate (SBC) index. The winter NAO index was correlated to this SBC index. Inter-annual fluctuations for most seabird, cetacean and fish populations were significant. Boreal species (e.g. gadiformes fish species, European storm petrel and Razorbill ,) with affinities to cold temperate waters declined significantly over time while two (Puffin and Killer Whale) totally disappeared from the area during the study period. Meridional species with affinities to hotter waters increased in population size. Those medium-term demographic trends may reveal a regime shift for this part of the Atlantic Ocean. Most of the specific observed trends were highly correlated to the SBC index and not to the NAO. Between 40% and 60% of temporal variations in species abundance were explained by the multivariate SBC index suggesting that the whole marine ecosystem is strongly affected by a limited number of physical parameters revealed by the multivariate SBC index. Aside the statistical error of the field measurements, the remaining variation unexplained by the physical characteristics of the environment correspond to the impact of anthropogenic activities such overfishing and oil-spills. [source] "Or, the Whale":,Unpopular Melville in the Popular Imagination, or a Theory of UnusabilityLEVIATHAN, Issue 3 2009Richard Hardack [source] Producing North and South: a political geography of hydro development in QuébecTHE CANADIAN GEOGRAPHER/LE GEOGRAPHE CANADIEN, Issue 2 2004Caroline Desbiens Since the 1970s, the tapping of James Bay's hydroelectric potential has been synonymous with the tapping of divergent national imaginaries for native and non-native people in Québec. Exploitation of natural resources in the region has activated different narratives of political identity for each community. I explore this evolving political context by examining how, for each group, water has emerged simultaneously as a physical entity possessing economic value and a social artefact supporting the consolidation of national boundaries. I do so by analysing three phases of changing relationships around resource management, namely: hydroelectric development on the La Grande river in the 1970s; the Cree opposition to Great Whale in the 1990s; and the recent agreement concerning a new relationship between the two parties. In each of these phases, nature has been both the symbolic and material tie that binds different national identities and materialises their boundaries. While these are not boundaries in the traditional geopolitical understanding of the term, the forging of an equitable framework of development in the region depends on the recognition of nature as a historical and political formation that answers to different sets of national preoccupations. Depuis les années 70, le développement hydroélectrique de la Baie James a favorisé l'expression de deux imaginaires nationaux dans la province, celui des autochtones en parallèle avec celui des non-autochtones. L'exploitation des ressources naturelles de la région a donné lieu à des récits identitaires propres à chaque communauté. J'explore les changements dynamiques de ce contexte politique en examinant comment, pour chacun de ces groupes, l'eau est à la fois une entité physique possédant une certaine valeur économique, ainsi qu'un objet social capable de consolider les frontières nationales de chaque peuple. L'analyse se fait à travers trois phases de gérance des ressources: la construction du Complexe La Grande dans les années 70; l'opposition des Cris au projet Grande Baleine dans les années 90; et la signature récente d'une nouvelle entente entre les deux parties. Dans chacune de ces phases, la nature a constitué un terrain à la fois symbolique et matériel consolidant des frontières nationales divergentes. Même s'il ne s'agit pas de frontières ,géopolitiques' au sens propre du terme, la création d'une structure de développement équitable dans la région exige que la nature soit perçue dans toute sa dimension historique et politique afin de dégager les différentes priorités nationales qui s'expriment en son nom. [source] Right Whales: Worldwide Status (The Journal of Cetacean Research and Management, Special Issue 2)FISH AND FISHERIES, Issue 4 2002John C. Goold No abstract is available for this article. [source] Test-taking Strategies of 12- and 13-year-old Hungarian Learners of EFL: Why Whales Have MigrainesLANGUAGE LEARNING, Issue 1 2006Marianne Nikolov This paper gives an account of a project exploring 12- and 13-year-old children's uses of strategies while solving reading and writing test tasks in English as a foreign language (EFL). The study was conducted to provide insights into how learners go about solving tasks and what they think and rely on while doing them. The first part provides an overview of strategy research and test-taking strategy research. The second part provides the background of the project and describes the 52 participants, the data collection instruments, and the procedures. The discussions include four case studies of two high achievers and two low achievers and explore what role individual differences played, what strategies learners applied, and how the findings have contributed to a better understanding of what we mean by test-taking strategies. This exploratory qualitative study raises several questions. The analyses of the particular strategies and case studies might provide valuable insights into learners' uses of strategies and useful feedback for test designers and teachers. [source] Fifty Years of Flukes and Flippers: A Little History and Personal Adventures with Dolphins, Whales and Sea Lions (1958,2007) by W. E. EvansMARINE MAMMAL SCIENCE, Issue 1 2010James T. Harvey Dr. No abstract is available for this article. [source] Activity budget and diving behavior of gray whales (Eschrichtius robustus) in feeding grounds off coastal British ColumbiaMARINE MAMMAL SCIENCE, Issue 3 2008Lei Lani Stelle Abstract Behavior and diving patterns of summer resident gray whales (Eschrichtius robustus) foraging on mysids were studied in coastal bays along the north shore of Queen Charlotte Strait, British Columbia. In this region, gray whales were found to feed primarily on planktonic prey rather than on the benthos as in their primary feeding areas further north. During the summers of 1999 and 2000, whales spent most of their time actively feeding or searching for prey (77%), whereas only 15% of their time was spent traveling and 8% socializing. The majority of the dives were short; the mean dive duration was 2.24 min with approximately three respirations per surfacing and 15 s between blows. Whales dove frequently (26.7 h,1), spending only 17% of their time at the surface with an overall blow rate of 1.14 respirations per minute. Activity states were characterized by significantly different diving and respiratory parameters; feeding whales dove more frequently, with shorter intervals between respirations, thus spending less time at the surface compared to when traveling or searching. This diving pattern differs from benthic-feeding whales and likely optimizes capture of the mobile mysid swarms in shallow waters. [source] Survival of Bowhead Whales, Balaena mysticetus, Estimated from 1981,1998 Photoidentification DataBIOMETRICS, Issue 4 2002Judith Zeh Summary. Annual survival probability of bowhead whales, Balaena mysticetus, was estimated using both Bayesian and maximum likelihood implementations of Cormack and Jolly-Seber (JS) models for capture-recapture estimation in open populations and reduced-parameter generalizations of these models. Aerial photographs of naturally marked bowheads collected between 1981 and 1998 provided the data. The marked whales first photographed in a particular year provided the initial ,capture' and ,release' of those marked whales and photographs in subsequent years the ,recaptures'. The Cormack model, often called the Cormack-Jolly-Seber (CJS) model, and the program MARK were used to identify the model with a single survival and time-varying capture probabilities as the most appropriate for these data. When survival was constrained to be one or less, the maximum likelihood estimate computed by MARK was one, invalidating confidence interval computations based on the asymptotic standard error or profile likelihood. A Bayesian Markov chain Monte Carlo (MCMC) implementation of the model was used to produce a posterior distribution for annual survival. The corresponding reduced-parameter JS model was also fit via MCMC because it is the more appropriate of the two models for these photoidentification data. Because the CJS model ignores much of the information on capture probabilities provided by the data, its results are less precise and more sensitive to the prior distributions used than results from the JS model. With priors for annual survival and capture probabilities uniform from 0 to 1, the posterior mean for bowhead survival rate from the JS model is 0.984, and 95% of the posterior probability lies between 0.948 and 1. This high estimated survival rate is consistent with other bowhead life history data. [source] A case study of shell at Sakhalin: having a whale of a time?CORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 3 2008Subhasis Ray Abstract This is a case study on the world's largest oil and gas project, at the Sakhalin Islands, Russia. Shell is the key promoter of this project. The case highlights the sustainability challenges that Shell faced when working on the mega-project. By their very nature, all such projects involve disruptions in the environmental and social fabric of the project site. NGOs often take up these issues and create international headlines, bringing pressure on the management team. The Russian government also changed its stand over a period of time. While many of these issues are valid in their own way, they often create managerial dilemmas. Traditional management approaches to community development and environmental conservation fell short of stakeholder expectations at Sakhalin. The issue of saving around 100 endangered whales put a cloud of doubt over this $20 billion project. The case highlights strategic issues involved in crafting sustainability strategies at mega-projects, possible pitfalls and the challenge of balancing project execution and stakeholder commitments against an unstable political backdrop. As Shell plans to start many exploration projects in bio-diversity rich parts of the world, the Sakhalin project acts as a pilot to and reminder of social responsibility challenges to big multi-nationals. Copyright © 2007 John Wiley & Sons, Ltd and ERP Environment. [source] Comparative hepatic activity of xenobiotic-metabolizing enzymes and concentrations of organohalogens and their hydroxylated analogues in captive greenland sledge dogs (Canis familiaris),ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2009Jonathan Verreault Abstract A captive study was performed with Greenland sledge dogs (Canis familiaris) fed a naturally organohalogen-contaminated diet (Greenland minke whale [Balaenoptera acutorostrata] blubber; exposed group) or a control diet (pork fat; control group). The catalytic activity of major xenobiotic-metabolizing phase I and II hepatic microsomal enzymes was assessed. Relative to control dogs, ethoxyresorufin- O -deethylase (EROD) activity in exposed dogs was twofold higher (p = 0.001). Testosterone hydroxylation yielded 6,- and 16,-hydroxy (OH) testosterone and androstenedione, with higher rates of production (23,27%; p , 0.03) in the exposed individuals. In the exposed dogs, epoxide hydrolase (EH) activity was 31% higher (p = 0.02) relative to the control dogs, whereas uridine diphosphoglucuronosyl transferase (UDPGT) activity was not different (p = 0.62). When the exposed and control dogs were combined, the summed (,) plasma concentrations of OH-polychlorinated biphenyl (PCB) congeners were predicted by plasma ,PCB concentrations and EROD activity (p , 0.04), whereas testosterone hydroxylase, EH, and UDPGT activities were not significant predictors of these concentrations. Consistent results were found for individual OH-PCB congeners and their theoretical precursor PCBs (e.g., 4-OH-CB-187 and CB-183, and 4-OH-CB-146 and CB-146) and for EROD activity. No association was found between ,OH,polybrominated diphenyl ether (PBDE) and ,PBDE plasma concentrations, or between potential precursor-metabolite pairs, and the enzyme activities. The present results suggest that liver microsomal EROD activity and plasma PCB concentrations have a greater (e.g., relative to EH activity) predictive power for the occurrence of plasma OH-PCB residues in sledge dogs. These results also suggest that plasma OH-PBDEs likely are not products of cytochrome P450-mediated transformation but, rather, are accumulated via the diet. [source] Sponge halogenated natural products found at parts-per-million levels in marine mammalsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2002Walter Vetter Abstract Several unknown, abundant brominated compounds (BCs) were recently detected in the blubber of dolphins and other marine mammals from Queensland (northeast Australia). The BCs were interpreted as potential natural products due to the lack of anthropogenic sources for these compounds. This study investigated whether some of the BCs accumulated by diverse marine mammal species are identical with natural BCs previously isolated from sponges (Dysidea sp.) living in the same habitat. Isolates from sponges and mollusks (Asteronotus cespitosus) were compared with the signals detected in the mammals' tissue. Mass spectra and gas chromatography retention times on four different capillary columns of the isolates from sponges and mammals were identical in all respects. This proves that the chemical name of the compound previously labeled BC-2 is 4,6-dibromo-2-(2,,4,-dibromo)phenoxyanisole and that the chemical name of BC-11 is 3,5-dibromo-2-(3,,5,-dibromo,2,-methoxy)phenoxyanisole. Using a quantitative reference solution of BC-2, we established that the concentrations of the brominated metabolites found in the marine mammals are frequently >1 mg/kg. The highest concentration (3.8 mg/kg), found in a sample of pygmy sperm whale (Kogia breviceps), indicates that BC-2 is a bioaccumulative, natural organohalogen compound. This is supported by the concentrations of the BCs in our samples being equal to the highest concentrations of anthropogenic BCs in any environmental sample. The quantitative determination of BC-2 in blubber of marine mammals from Africa and the Antarctic suggests that BC-2 is widespread. These results are direct proof that marine biota can produce persistent organic chemicals that accumulate to substantial concentrations in higher trophic organisms. [source] "OUR HOME IS DROWNING": IÑUPIAT STORYTELLING AND CLIMATE CHANGE IN POINT HOPE, ALASKA,GEOGRAPHICAL REVIEW, Issue 4 2008CHIE SAKAKIBARA ABSTRACT. Contemporary storytelling among the IÑupiat of Point Hope, Alaska, is a means of coping with the unpredictable future that climate change poses. Arctic climate change impacts IÑupiat lifeways on a cultural level by threatening their homeland, their sense of place, and their respect for the bowhead whale that is the basis of their cultural identity. What I found during my fieldwork was that traditional storytelling processed environmental changes as a way of maintaining a connection to a disappearing place. In this article I describe how environmental change is culturally manifest through tales of the supernatural, particularly spirit beings or ghosts. The types of IÑupiat stories and modes of telling them reveal people's uncertainty about the future. Examining how people perceive the loss of their homeland, I argue that IÑupiat storytelling both reveals and is a response to a changing physical and spiritual landscape. [source] Assessing the preservation of biogenic strontium in fossil bones and tooth enamelINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 1-2 2003K. A. Hoppe Abstract Analyses of the strontium isotope ratio (87Sr/86Sr) of vertebrate fossils can provide information about palaeobiological attributes such as habitat use and movement patterns. Diagenetic contaminants can alter the 87Sr/86Sr ratio of fossils, however, complicating palaeobiological interpretations. Several pretreatment protocols have been developed to separate diagenetic contaminants from biogenic Sr. While these methods can remove some diagenetic Sr, it has not been shown that any technique removes all contamination. The extent to which pretreatment removes diagenetic Sr can be quantified through analysis of the 87Sr/86Sr ratios of fossil marine mammal bones and teeth buried in sediments with non-marine diagenetic 87Sr/86Sr signatures. To do this, we examined Holocene seals recovered from archaeological sites in Greenland and California, as well as a Miocene whale from Maryland. Our results demonstrate that although pretreatment eliminated some contaminants from bone, a large percentage (up to 80%) of diagenetic Sr remained after treatment. In contrast, pretreatment does appear to remove nearly all (,,95%) diagenetic Sr from tooth enamel. Copyright © 2003 John Wiley & Sons, Ltd. [source] Morphological specializations of baleen whales associated with hydrodynamic performance and ecological nicheJOURNAL OF MORPHOLOGY, Issue 11 2006Becky L. Woodward Abstract Feeding behavior, prey type, and habitat appear to be associated with the morphological design of body, fluke, and flippers in baleen whales. Morphometric data from whaling records and recent stranding events were compiled, and morphometric parameters describing the body length, and fluke and flipper dimensions for an "average" blue whale Balaenoptera musculus, humpback whale Megaptera novaeangliae, gray whale Eschrichtius robustus, and right whale Eubalaena glacialis were determined. Body mass, body volume, body surface area, and fluke and flipper surface areas were estimated. The resultant morphological configurations lent themselves to the following classifications based on hydrodynamic principles: fast cruiser, slow cruiser, fast maneuverer, and slow maneuverer. Blue whales have highly streamlined bodies with small, high aspect ratio flippers and flukes for fast efficient cruising in the open ocean. On the other hand, the rotund right whale has large, high aspect ratio flukes for efficient slow speed cruising that is optimal for their continuous filter feeding technique. Humpbacks have large, high aspect ratio flippers and a large, low aspect ratio tail for quick acceleration and high-speed maneuvering which would help them catch their elusive prey, while gray whales have large, low aspect ratio flippers and flukes for enhanced low-speed maneuvering in complex coastal water habitats. J. Morphol., 2006. © 2006 Wiley-Liss, Inc. 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