• Fisheries and Aquatic Sciences
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• v.4 no.2
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• pp.65-69
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• 2001

For the first time the concentrations of copper, zinc, lead, cadmium and crome in the tissues from 17 specimens of cetaceans of Korean coast were determined. The measured concentrations of trace elements were considerably lower than the concentrations previously reported in cetaceans. In inter-species, Cd levels were higher in the kidney of Stejneger's beaked whales and the stomach, liver and lung of Risso's dolphin than in the tissues of minke whale and humpback whale.

• Proceedings of the Korean Environmental Health Society Conference
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• 2002.04a
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• pp.69-73
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• 2002

There have been few reports on the survey of pathological findings of cetaceans stranded on the coast of Japan. This is partly because of lack of the procedures and/or network of systemic sampling of fresh tissues for the pathological study of stranded marine mammals. In contrast, there are a numbers of reports on the cause of illness and death in wild, free-living cetaceans examined in other countries; the commonest cause of death was parasitic and bacterial pneumonia except for entanglement in fishing gear. Anthracosis, lung and hilar lymph nodes polluted by suspended particulate matter in the air, has been recently found in some cetaceans stranded on the coast of Japan. In addition to the data from the chemical analysis of tissues, scientific data obtained from pathological study of stranded marine mammals would be also one of the useful base for the assessment of global environment. Usefulness of metallothionein in the hepatopancreas of crabs as a biomarker of marine pollution monitoring was also discussed in this study.

• Journal of Marine Bioscience and Biotechnology
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• v.6 no.2
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• pp.102-109
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• 2014

Cetaceans (whales, dolphins, and porpoises) are aquatic mammals that experienced drastic changes during the transition from terrestrial to aquatic environment. Morphological changes include streamlined body, alterations in the face, transformation of the forelimbs into flippers, disappearance of the hindlimbs and the acquisition of flukes on the tail. For a prolonged diving, cetaceans acquired hypoxia-resistance by developing various anatomical and physiological changes. However, molecular mechanisms underlying these adaptations are still limited. CREB-binding protein (CREBBP) is a transcriptional co-activator critical for embryonic development, growth control, metabolic homeostasis and responses to hypoxia. Natural selection analysis of five cetacean CREBBPs compared with those from 15 terrestrial relatives revealed strong purifying selection, supporting the importance of its role in mammals. However, prediction for amino acid changes that elicit functional difference of CREBBP identified three cetacean specific changes localized within a region required for interaction with SRCAP and in proximal regions to KIX domain of CREBBP. Mutations in CREBBP or SRCAP are known to cause craniofacial and skeletal defects in human, and KIX domain of CREBBP serves as a docking site for transcription factors including c-Myb, an essential regulator of haematopoiesis. In these respects, our study provides interesting insights into the functional adaptation of cetacean CREBBP for aquatic lifestyle.

• Ocean and Polar Research
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• v.33 no.1
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• pp.35-43
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• 2011

Blubber plays different biological roles in cetaceans, including structural support, physiological demands (thermoregulation, streamlining, buoyancy, etc.), and energy storage. As such, biochemical composition, especially lipid, in the blubber may be vertically stratified in order to effectively assist with these functions. We analysed lipid content, class and fatty acid composition in the blubber of by-catch minke whale (Balaenoptera acutorostrata; n = 11), long-beaked common dolphin (Delphinus capensis; n = 3) and Pacific white-sided dolphin (Lagenorhynchus obiquidens; n = 2) from Korean waters. Lipid content for all three species ranged from 55 to 96% of wet weight, with a dominance of triacylglycerols. Vertical stratification of blubber lipid content was different between species. For minke whale and longbeaked common dolphin, it increased from inner (near the muscle) to outer (near the skin) layer, whereas it decreased for Pacific white-sided dolphin. Thirty-one fatty acids were found in all blubber samples and vertical stratification of fatty acid composition was similar among all three species. Among grouped fatty acids, monounsaturates were the most abundant, gradually increasing from inner to outer blubber layer, whereas polyunsaturates and saturates decreased. Such vertical stratification of lipid content and composition suggests that the modification and accumulation of lipid occur in the blubber itself in order to help cetaceans with their specific physiological needs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.704-713
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• 2018

Globally, the survival of many marine mammals is threatened by entanglement in fishing gear and there is also a high bycatch in Korea. This study analyzed the bycatch data of most cetacean species for Korean waters from 2011 to 2017, including the narrow-ridged finless porpoise Neophocaena asiaeorientalis, common dolphin Delphinus delphis, common minke whale Balaenoptera acutorostrata, and Pacific white-sided dolphin Lagenorhynchus obliquidens. A total of 12,262 cetaceans were captured as bycatch. In the Yellow and South Seas, the main species affected was the narrow-ridged finless porpoise, with 82.9% caught in stow nets and 11.5% captured in trawls. In the East Sea, the common minke whale, common dolphin, and Pacific white-sided dolphin were reported. The main common minke whale bycatch (43.5%) was in set nets, while common dolphins (49.0%) and Pacific white-sided dolphins (91.4%) were mainly caught in gill nets. The narrow-ridged finless porpoise, common dolphin, and common minke whale were most commonly reported in March, April, and May, while the Pacific white-sided dolphin was most frequently captured as bycatch in January and December. Each of these factors (season and gear responsible for bycatch) depended on the characteristics of the cetacean species. To conserve cetaceans, it is necessary to reduce the bycatch.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.6
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• pp.875-882
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• 2016

The numbers of books, news articles, and documentary films on whales and dolphins have increased dramatically in Korea. The translation of 37 species with established Korean names, as reviewed and reported by Sohn et al. (2012), Kim et al. (2010), and Kim et al. (2013) in those books and public media, was not a problem. However, 52 cetacean species, which do not have proper Korean names, have been translated into Korean, causing confusion in the public. This short note suggests Korean translations for common names that have no Korean names based on the origins of the English common names, recent scientific information, and books on cetaceans.

• Ocean Science Journal
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• v.43 no.4
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• pp.175-182
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• 2008

Bottlenose dolphins are the only cetaceans regularly observed in the northern Adriatic Sea, but they survive at low densities and are exposed to significant threats. This study investigates some of the factors that influence habitat use by the animals in a largely homogeneous environment by combining dolphin data with hydrological and physiographical variables sampled from oceanographic ships. Surveys were conducted year-round between 2003 and 2006, totalling 3,397 km of effort. Habitat modelling based on a binary stepwise logistic regression analysis predicted between 81% and 93% of the cells where animals were present. Seven environmental covariates were important predictors: oxygen saturation, water temperature, density anomaly, gradient of density anomaly, turbidity, distance from the nearest coast and bottom depth. The model selected consistent predictors in spring and summer. However, the relationship (inverse or direct) between each predictor and dolphin presence varied among seasons, and different predictors were selected in fall. This suggests that dolphin distribution changed depending on seasonal forcing. As the study area is relatively uniform in terms of bottom topography, habitat use by the animals seems to depend on complex interactions among hydrological variables, caused primarily by seasonal change and likely to determine shifts in prey distribution.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.5
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• pp.513-522
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• 2012

This paper reviews the Korean vernacular names of 35 cetacean species found in Korean waters and mentioned in 19 references, including laws, high school textbooks, and books on whales. The vernacular names of 16 species were identical in all sources examined. Some names have their origins in old Korean books, while others have recently entered public awareness through movies, TV programs, and the mass media; some species are frequently studied by researchers. Given the nature of vernacular names, that is, names used by people who live in sympatry with the animals, priority was not given high consideration in this paper. Instead, we carefully investigated the origin, publicity, and rationale of the Korean common names for the 35 species. All of these Korean names are also listed in "The World Cetacea Database (http://www.marinespecies.org/cetacea/)," which contains the most accurate cetacean systematic information on the Web.

• Animal cells and systems
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• v.14 no.4
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• pp.291-296
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• 2010

Population ecological characteristics of growth and mortality play an important role in understanding the population dynamics of marine mammals. The instantaneous coefficients of natural and bycatch mortality were estimated for minke whales (Balaenoptera acutorostrata) in Korean waters using a population assessment model composed of bycatch and abundance data. The survivorship curve of this population was fitted to the data, and then the curve was revised using age-specific relative bycatchability coefficients ($q_t$). Instantaneous coefficients of natural and bycatch mortality of minke whales were estimated as 0.024/year and 0.076/year, respectively, and from this the survival rate was estimated as 0.905. This estimated survival rate was comparable to other cetaceans in other regions. The $q_t$ for this population ranged from 0.020 to 0.193. The revised survival rates were higher when the $q_t$ was taken into account. The mortality coefficient, survival rate, $q_t$ and survivorship curves had not previously been determined for minke whale in this area. This estimate could serve as fundamental information to assess the status of this population and for conservation and rational management.

• The Journal of Fisheries Business Administration
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• v.53 no.2
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• pp.42-57
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• 2022

The purpose of this study was to estimate the economic values of whale watching. The data used in this study were collected with 1,599 coastal tourists and the questionnaire included contingent valuation method questions. The results show that coastal tourists obtained the benefits of about KRW 15,970 from whale watching. Further analyses were conducted to check the differences of willingness to pay for whale watching based on the three variables as follows: previous experience of whale watching and participation intention in whale watching tourism, and previous experience of cruise trips. The results indicate that the respondents, who already participated or intended to participate in this type of tourism activity, were willing to pay higher than those, who did not participated or had no intention of participation, respectively. These results imply that whale watching could be a feasible alternative to the direct consumption of whale meat. Based on the study results, we provide policy and management-related implications for whale watching programs.