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Abstract: The spatial and temporal distribution pattern of stranded cetaceans in Korean waters was investigated for the conservation and management of cetaceans in this area. A total of 154 cetacean [...]

Abstract: Status of Indo-Pacific bottlenose dolphins (Tursiops aduncus) around Jeju Island, Korea, was assessed using potential biological removal (PBR) and mortality data. Considering the 2009 estimated abundance of Indo-Pacific bottlenose [...]

Abstract: Structure of the southwestern East Sea ecosystem and role of common minke whales (Balaenoptera acutorostratd) in this ecosystem during the postcommercial whaling moratorium (post-CWM) period (1986-2007) were examined using [...]

A new sound insulation metamaterial (SIM) is designed by combining a Helmholtz resonator and a fractal structure for sound insulation in the frequency range of 600 to 1700 Hz. Using a fractal-based internal structure, the designed hybrid SIM shows a relatively constant value of sound transmission loss (STL) over the target frequency range. The basic concept of this work is to develop two functional parts working in each effective frequency range. One is a Helmholtz resonance structure that operates with a high value of STL from 600 to 1000 Hz, and the other is an internal fractal structure that shows a high STL at higher frequencies in the 1000 to 1700 Hz range. In this work, the proposed metamaterial has a mean of 16.34 dB with a standard deviation of 1.73 dB within the wide target range of 600 to 1700 Hz. Additionally, the proposed SIM is approximately 40 % smaller in size than the previous resonator and has a higher mean STL with a small ΔSTL of 1.7 dB between highest and lowest values. [ABSTRACT FROM AUTHOR]

Bycatch of marine mammals in fishing gear is a global problem, and considered a significant threat to cetaceans in the East Sea. The characteristics of cetacean bycatches in this area between 2013 and 2014 were investigated. The Korea Coast Guard reported a total of 717 cetacean bycatches involving 10 species. Four species, spinner dolphins ( Stenella longirostris ), long-beaked common dolphins ( Delphinus capensis ), minke whales ( Balaenoptera acutorostrata ), and finless porpoises ( Neophocaena asiaeorientalis ) accounted for 95.6% of the bycaught cetaceans. More bycatches occurred in the spring (49.8%) than in other seasons, with a peak in April (22.0%). Most bycatches involved three types of fishing gear: set nets, pots and gill nets (n = 706; 98.5%). The remaining bycatches were associated with trawl nets (n = 4; 0.6%). Most bycatches took place within 5 M of land (n = 504; 79.5%). [ABSTRACT FROM AUTHOR]

We investigated the stomach contents of 54 minke whales (Balaenoptera acutorostrata) from bycatch in Korean waters from 2000 to 2008 to examine their diet and feeding habits. Body length of the whales ranged from 3.9 to 8.5 m with a mean of 5.45 m (SD =1.07 m). A total of 10 prey species (3 crustacean, 5 fish and 2 cephalopod) were identified from the whale stomachs. We used the Combined Rank Index (CRI) to estimate the relative importance of prey species.Euphausia pacificawas the most important prey species in this sample, occurring in 70.4% (n=38) of the stomachs. Pacific anchovy (Engraulis japonicus) was the second most important prey species, occurring in 11.1% (n=6) of the stomachs. Most minke whale stomachs contained a single prey species (74.5%). Euphausiids were found in the majority of the stomachs of all whale length-classes and they also were the dominant prey species in most seasons except for autumn. This information can be useful for the understanding of the trophic role of minke whales in this area. [ABSTRACT FROM PUBLISHER]

The feeding habits of the sand shrimpCrangon hakodateiin the East Sea (Korea) were investigated through analysis and comparison of the stomach contents of 602 individuals according to season, shrimp size class, and prey diversity. The diet ofC. hakodateiconsisted of 17 prey categories mainly comprising crustaceans, molluscs, polychaetes, nematodes, algae, and fishes, with crustaceans dominating the diet. Molluscs, nematodes, and fishes were also important prey, whilst other categories including polychaetes and algae comprised small percentages of the diet. For smallC. hakodateiindividuals (<10 mm carapace length [CL]), amphipods and mysids comprised more than 67% of the prey in both relative abundance and frequency of occurrence. Large individuals (>10 mm CL) tended to be more dependent on amphipods than mysids. Amphipods and mysids together constituted the dominant prey, accounting for more than 50% of the diet in terms of both percent occurrence and relative abundance. The abundance and occurrence of prey showed a seasonal variation, with amphipods and mysids being the predominant prey in autumn (45%), winter (30%), and spring (40%). Amphipods were the dominant prey with regard to season, size class, sex, and area. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to describe the conceptualization, development, and implementation processes of the newly established Korean Cardiac Arrest Resuscitation Consortium (KoCARC) to improve out-of-hospital cardiac arrest (OHCA) outcomes., Methods: The KoCARC was established in 2014 by recruiting hospitals willing to participate voluntarily. To enhance professionalism in research, seven research committees, the Epidemiology and Preventive Research Committee, Community Resuscitation Research Committee, Emergency Medical System Resuscitation Research Committee, Hospital Resuscitation Research Committee, Hypothermia and Postresuscitation Care Research Committee, Cardiac Care Resuscitation Committee, and Pediatric Resuscitation Research Committee, were organized under a steering committee. The KoCARC registry was developed with variables incorporated in the currently existing regional OHCA registries and Utstein templates and were collected via a web-based electronic database system. The KoCARC study population comprises patients visiting the participating hospitals who had been treated by the emergency medical system for OHCA presumed to have a cardiac etiology., Results: A total of 62 hospitals volunteered to participate in the KoCARC, which captures 33.0% of the study population in Korea. Web-based data collection started in October 2015, and to date (December 2016), there were 3,187 cases compiled in the registry collected from 32 hospitals., Conclusion: The KoCARC is a self-funded, voluntary, hospital-based collaborative research network providing high level evidence in the field of OHCA and resuscitation. This paper will serve as a reference for subsequent KoCARC manuscripts and for data elements collected in the study.