• 한국해양학회지:바다
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• 제24권3호
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• pp.475-482
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• 2019

일제강점기 황해에서 일본 포경회사에 포획된 대형 수염고래류는 참고래 3,173마리, 대왕고래 7마리, 혹등고래 28마리를 합하여 총 3,200마리 이상이 포획되었다. 이러한 대량포획으로 황해에서 대형 수염고래류가 거의 소멸되었다. 황해는 대형 수염고래류가 서식하기에 적합한 수온조건($4{\sim}26^{\circ}C$)과 풍부한 먹이 조건을 갖추고 있어 동계와 춘계에 대형 수염고래류의 출현이 많았던 것으로 추정된다. 동계와 춘계에 참고래가 많이 포획된 것은 이들의 주 먹이인 태평양크릴새우(Euphausia pacifica)가 표, 중층에 많아 이들이 이 시기에 대량 회유한 것에 기인된다. 그러나 수온약층이 강하게 형성되는 여름과 가을에는 태평양크릴새우가 수온약층 아래에 분포하여 포식 조건이 좋은 다른 해역(울산 해역)으로 이동한 것으로 보인다.

• Animal cells and systems
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• 제15권1호
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• pp.79-84
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• 2011

The status of J stock minke whales (Balaenoptera acutorostrata) was assessed using potential biological removal (PBR) and mortality data. Using the estimated abundance of minke whales in this area (6260; CV = 0.212), the minimum population estimate of the stock was estimated as 5247. The PBR for J stock minke whales was calculated as 52.5 individuals using the minimum population estimate (5247), one-half of the maximum theoretical net productivity rate (0.02) and the recovery factor (0.5). The estimated mean annual level of anthropogenic mortality was 270.4 individuals. Thus, the status of this stock was considered as strategic. However, fortunately, the abundance of this population in the East Sea from 2000 to 2008 showed an increasing trend (rate of increase 0.0488; annual rate of increase 5.0%) although it is not statistically significant (P > 0.05). The primary sources of anthropogenic mortality were bycatch (set nets, pots and gill nets) and illegal catch. Because of the status of this population, it is urgently necessary to reduce the amount of bycatch and illegal catch of minke whales. Further study needs to use population health and viability analysis for investigating the long-term survival of this population more clearly.

• 한국해양바이오학회지
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• 제7권2호
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• pp.35-41
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• 2015

Whales are marine mammals that are fully adapted to aquatic environment. Whales breathe by lungs so they require adaptive system to low oxygen concentration (hypoxia) while deep and prolonged diving. However, the study for the molecular mechanism underlying cetacean adaptation to hypoxia has been limited. Hypoxia-inducible factor (HIF) is the central transcription factor that regulates hypoxia-related gene expression. Here we identified HIF-binding sites in whale genome by phylogenetic footprinting and analyzed HIF-target genes to understand how whales cope with hypoxia. By comparison with the HIF-target genes of terrestrial mammals, it was suggested that whales may retain unique adaptation mechanisms to hypoxia.

• 융합신호처리학회논문지
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• 제19권4호
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• pp.147-152
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• 2018

수중에서의 일시적인 신호는 복잡하고, 변화가 심하며, 비선형적이므로 신호의 패턴을 정확히 모델링하기 어렵다. 본 논문에서는 수중 신호 중 하나인 고래 소리를 선택하여 음성분석 기법에 많이 사용하는 Cepstral 분석에 의한 MFCC 추출법을 이용하여 분석하였고, MFCC와 $L_2$-norm 최소화 기법을 이용하여 고래소리를 재생하였다 실험 분석에 사용된 고래의 종류는 혹등고래(Humpback whale), 참고래(Right whale), 대왕고래(Blue whale), 귀신고래(Gray whale), 밍크고래(Minke whale) 등 5종으로서 과거 한반도 동해안에 출몰한 적이 있는 고래들이다. 원본 고래소리에서 MATLAB프로그래밍을 이용하여 20차 MFCC계수들을 추출한 후 이를 가중 $L_2$-norm 최소화를 이용한 MFCC역변환을 통해 재생한다. 최종적으로 가중치가 3~4의 값에서 고래소리 재생이 가장 적합함을 알 수 있었다.

• 수산해양기술연구
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• 제58권3호
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• pp.281-287
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• 2022

The distributions of common minke whales observed in the East Sea in ten surveys in May of 2003, 2005, 2006, 2007, 2009, 2010, 2012, 2015, 2016 and 2020 were investigated using satellite sea surface temperature (SST) derived from the Moderate Resolution Imaging Spectrometer (MODIS). Most of the minke whales were observed in the waters off the Korean Peninsula at 36-38.5° N, which is expected as the highly productive coastal upwelling area. Yet, no minke whale was observed in 2006 when a relatively larger scale coastal upwelling occurred with SST at 11℃. In 2016 and 2020, the warm water higher than 17℃ extended widely in the area, and the minke whales were observed in the offshore waters, deeper than 1,000 m. 87.5% of minke whales observed in May appeared in the SST from 13 to 16℃, and they seemed to avoid relatively high temperatures. This suggests that optimum habitat water temperature of minke whales in May is 13-16℃. The SST in the area had risen 1.67℃ from 2003 to 2021, and it was remarkably higher than in other parts of the surrounding areas. The future temperature rising may change the route and timing of the migration of minke whales in the study area.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 공동학술발표회
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• pp.84-84
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• 2017

• 한국수산과학회지
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• 제50권6호
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• pp.799-805
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• 2017

The whistle sounds of three Beluga whales Delphinapterus leucas were recorded four times, for an hour each time, in 2016 and analyzed to obtain the most stable and basic acoustic characteristics of the whales in captivity. This study investigated the whistle characteristics of beluga whales and the relationship between whistle sounds and behavior to understand the meaning of the whistle sounds. The whistles were classified into six types (flat, ascending, descending, hump, dip, and wavy type) by their frequency contour and shape. The most common type was the ascending type, accounting for>30% of total whistles. The fundamental frequency of whistles was 2.0-8.6 kHz. Four types of behavior were related with the sounds of beluga whales (aggressive, submissive, affiliative, sexual behavior). A flat whistle was the most recorded in the group and an aggressive act was observed in association with the flat whistle. A dip whistle were recorded more when submissive acts were observed.

• Animal cells and systems
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• 제13권4호
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• pp.419-427
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• 2009

The Minke whale, Balaenoptera acutorostrata, is the smallest baleen whale in the suborder Mysticeti. Because this species inhabits coastal areas, it became a main target species of coastal small-type whaling in the North Atlantic and the Northwest Pacific Oceans, and the species' population size dramatically decreased because of over-exploitation. As a result, the International Whaling Commission declared a global moratorium on whaling and launched the development of a management procedure for protecting the whales. Morphological studies, whaling history analysis, and genetic studies conducted mainly by Japanese scientists showed the existence of one unique "E" stock that inhabits the waters around the Korean peninsula and mixes with the "O" stock in the southern part of the Sea of Okhotsk. We used the mitochondrial DNA control region polymorphism of 348 Minke whales bycaught or stranded in Korean waters from 30 October 1998 to 25 June 2005 to assess the whale population structure by year. The frequency of the 10 major haplotypes from the 40 identified haplotypes was not significantly different among groups, suggesting that a subpopulation was not present. A comparison of the genetic distances calculated with Tamura-Nei's method showed that the distances between groups were lower than those within groups, which suggests that there was no genetic difference in the Minke whale populations. The Fst comparison between groups and the phylogenetic tree constructed using the unweighted pair group method with arithmetic mean (UPGMA) and Neighbor Joining (NJ) method also detected no obvious sub-stock structure.

• Animal cells and systems
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• 제14권4호
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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.

• 수산경영론집
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• 제49권1호
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• pp.51-66
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• 2018

During the Joseon period, the East Sea would be called 'Gyeonghae' due to a large number of whales. In the Republic of Korea, whaling was locally permitted in 1946. However, the number drastically dropped because the hunting of the marine mammal had already been carried out in Russia, the U.S. and Japan since 1800s. Before a moratorium on commercial whaling was introduced by the International Whaling Commission(IWC) in 1986, whale populations in the East Sea had plunged. Furthermore, Korean gray whales and fin whales weren't found anymore in that area. With the suspension, whale hunting was banned in Korea as well. Even so, accidentally caught whales have been allowed to be distributed on the market with respect for local food culture. With the establishment of Whale Museum and hosting of the 57th Annual Meeting of the International Whaling Commission(IWC) at Jangsaengpo in 2005, whale tourism was facilitated in earnest. This whale tourism has been operated by Nam-gu Office and Nam-gu City Management Corporation in Ulsan. However, the popularity of whale tourism has increased a demand for whale meat. At the same time, there has been concern over decrease in whale populations because of illegal whaling. In addition, a conflict between the use and protection of whales has caused confusion in tourism identity. Actually, there is a serious doubt on the sustainability of whale tourism due to the decade-long deficit and excessive investments. This study attempts to define a concept of whale tourism and propose a future direction for the sustainable growth and development of Korea's whale tourism industry after developing such comprehensive assessment indicators as a basic research for the introduction of sustainable whale tourism. To achieve the aim of this study, AHP(Analytic Hierarchy Process) was chosen as a main research tool and the factors were ranked by a comprehensive analysis of principal factors and detail factors. The current study showed the following results. First, ecological environment(0.430) was indicated the most important factor of whale tourism assessment indicators. Moreover, Population(0.1302), Action for Cetacean protection(0.1031), Governance(0.0898) were critical factors. On the other hand, Accommodations(0.0085), Whale meat(0.0088) were unimportant factors than others.