This study aimed to improve safety and reduce labor intensity in offshore crab pot fisheries through the development of six types of automated fishing gear: a bait cutter, bait crusher, mainline arranging device, automatic pot hauler, cold water tank system, and crab pot unloading device. Sea trials demonstrated that both the bait cutter and bait crusher effectively reduced overall operation time. The mainline arranging device lowered the risk of injury compared to the conventional manual handling. The automatic pot hauler enabled the automated separation of crab pots, significantly decreasing the physical workload. The cold water tank system facilitated the efficient sorting of live crabs while enhancing onboard safety. Additionally, the crab pot unloading device reduced physical strain on workers and minimized catch damage. A satisfaction survey revealed high levels of approval among fishers, particularly regarding labor reduction and improved safety. Economic analysis indicated that vessels equipped with the automated gear experienced reduced overall operating costs. These findings suggest that the developed technologies will contribute to the long-term sustainability and modernization of offshore crab pot fisheries.

This study examined the operational characteristics and fishing performance of an offshore pot fishery targeting swimming crabs (Portunus trituberculatus) to identify key issues and proposed strategies for improving efficiency and fisher safety. Analysis was based on approximately one year of fishing logbook data recorded by a pot fishing vessel. The total annual catch amounted to 30,084 kg, with the highest catch per unit effort of 0.07 kg per trap observed in autumn at depths of 20–25 m. No crabs were caught below 15℃ while the peak catch occurred at around 25℃. Catches were geographically concentrated in the mid-northern West Sea, especially near Taean and Boryeong. Economically important bycatch species, including sand crabs, octopus, and turban snails, exhibited distinct spatial distributions. An average of 1,996 traps were deployed per operation with a low loss rate of 1.6 traps. Based on field-level observations, this study proposed the development of automated or semi-automated equipment, such as bait cutters, automatic mainline arranging devices, pot-hauling and separation systems, chilled water tanks for sorting, and automated unloading systems. These technologies are expected to reduce labor demands, improve safety, and enhance the overall operational efficiency of the pot fishery.

The Indian Ocean is the second-largest tuna fishing ground in the world, accounting for approximately 1.2 million tonnes (23%) of the estimated 5.2 million tonnes of global commercial tuna catch in 2023. This study examined the relationship between tuna catches, specifically skipjack, bigeye, and yellowfin tunas, and prey biomass (Nautical Area Scattering Coefficient, NASC) estimated from acoustic surveys conducted in the southwestern Indian Ocean from 20 April to 15 May 2019. Environmental variables were derived from the Copernicus Ocean Model, and tuna length data from the IOTC. The estimated total tuna catch in the study area was approximately 166,400 tonnes, with the northwestern region showing the highest catches and NASC values. Tuna catches increased with NASC; however, the relationship was non-linear. While skipjack showed no significant correlation with NASC, bigeye and yellowfin tunas exhibited weak but significant positive correlations. Environmental analysis revealed that the northern waters had high surface temperatures, low salinity, and low oxygen levels, with mid and deep layers characterized by low temperature, salinity, oxygen, and chlorophyll. These findings offer a foundation for understanding tuna distribution in relation to prey and environmental conditions, highlighting the need for future species- and fishery-specific studies to support sustainable tuna resource management.

This study aimed to enhance the operational efficiency and safety of offshore eel trap fisheries by developing six types of automated fishing equipment: a bait crusher, bait cutter, main line arranging device, trap cleaning device, eel sorting device, and fish pump system. Sea trials demonstrated that the bait crusher and bait cutter significantly reduced manual labor and processing time while maintaining bait quality. The main line arranging device improved productivity and safety by automating the sorting of looped cords. The trap cleaning device effectively removed fouling organisms using high-pressure water and rotating brushes. The eel sorting device enabled automatic size-based selection, improving resource management and operational efficiency. The fish pump system transferred eels rapidly with minimal physical damage, reducing unloading time by over 80% and decreasing labor requirements. A satisfaction survey of fishery participants confirmed that all developed devices were highly effective in reducing workload, enhancing safety, and improving operational performance. The automated equipment developed in this study is expected to contribute to the sustainable management of offshore eel trap fisheries and to offer potential applicability to other coastal and offshore fisheries.

This study examined the offshore eel trap fishing process using one year of fishing logs and fishermen’s insights to identify key operational challenges and propose equipment improvement for greater efficiency and safety. Conger eel catches varied significantly by season, depth, and temperature, peaking in winter at 85–90 m and 23°C. The western waters of Jeju Island were identified as a major fishing ground, with the highest catch recorded in November and the lowest in July, reflecting seasonal trends. Each fishing operation deployed about 10,000 traps, with an average loss of 38 traps, posing economic concerns. The process involved intensive manual labor in bait preparation, trap retrieval, catch separation, line loading, and unloading, leading to high physical demands and safety risks. To address these issues, the study proposed automation through the development of a line loading device, trap cleaning device, bait processing machine, and automatic catch separator. These innovations could reduce the labor force required by one to two workers per process, alleviate workloads, and enhance resource management. By integrating quantitative logbook analysis with field-based knowledge, this study offers practical value. Further research is recommended on automation development, cost-effectiveness, and field validation to support safer and more sustainable eel trap fisheries.

We presented foundational findings regarding the occurrence and acoustic characteristics of the finless porpoise through passive acoustic and visual surveys conducted on the southern coast of Korea, specifically at Hadong Jungpyeong Port. Over a survey period spanning from July 8 to August 16, 2023, totaling 40 days, we observed peaks in the number of clicks produced by this species on July 15, July 24, August 4, August 11, and August 16. The highest count, totaling 18,924 clicks, was recorded on July 15th, while the lowest count, at 3,888 clicks, occurred on August 8th. Examining the acoustic characteristics throughout the diurnal cycle, we found that the peak activity in terms of DPM (detection positive minute for one hour), DP10M (DPM for ten minutes), and overall number of click sounds was observed between 05:00 and 08:00, with a secondary peak occurring from 17:00 to 18:00. The quietest period was noted between 23:00 and 02:00. Furthermore, there was a significant increase in the number of clicks from sunrise, with the maximum count of 21,581 clicks recorded at 6 AM. This count gradually decreased until noon, experienced a slight increase thereafter, peaked again at sunset, and then declined. The dominant frequency mode of this species was 126 kHz, with a concentration ranging from 112 to 136 kHz. The average duration of a click sound was 127 ㎲, with approximately 16 sinusoids (cycles) within each click sound and an average cycle length of approximately 7.9 ㎲. These findings from our study are anticipated to serve as foundational data for the development of a Korean pinger and acoustic warning system.

Recently, domestic fishing production of Japanese horse mackerel has been continuously decreasing. To achieve sustainable fishing of this species, it is essential to acquire its target strength (TS) for accurate biomass estimation and to study its ecological characteristics. To date, there has been no TS research using a broadband echosounder targeting Japanese horse mackerel. In this study, for the first time, we synchronized an underwater camera with a broadband frequency (nominal center frequency of 200 kHz, range: 160-260 kHz) to measure the TS according to the body size (16.8-35.5 cm) and swimming angle of the species. The relationship between Japanese horse mackerel length and body weight showed a general tendency for body weight to increase as length increased. The pattern of the frequency spectra (average values) by body length exhibited a similar trend regardless of body length, with no significant fluctuations in frequency observed. The lowest TS value was observed at 243 kHz while the highest TS values were recorded at 180 and 257.5 kHz. The frequency spectra for the swimming angles appeared to be flat at angles of –5, 0, 30, 60, 75, and 80° while detecting more general trends of frequency spectra for swimming angle proved challenging. The results of this study can serve as fundamental data for Japanese horse mackerel biomass estimation and ecological research.

Agarum clathratum (A. clathratum) is a marine brown algal species that belongs to the Costariaceae family and has antioxidant and anti-microbial properties. However, the anti-inflammatory effects of A. clathratum and the molecular mechanisms involved have not been determined so far. This study aimed to investigate the anti-inflammatory effects of A. clathratum extracts in THP-1 macrophages stimulated by lipopolysaccharide (LPS) derived from Porphyromonas gingivalis. The THP-1 cells were differentiated with 12-O-tetradecanoylphorbol-13-acetate and treated with A. clathratum before LPS stimulation. Cell viability was assessed using the trypan blue exclusion assay. The expression of pro-inflammatory response-associated molecules was evaluated by quantitative real-time polymerase chain reaction and Western blot analysis. A. clathratum treatment inhibited the expression of interleukin-1β in LPS-stimulated THP-1 macrophages without causing any cytotoxicity. The anti-inflammatory effect of A. clathratum resulted in a significant repression of the JNK/c-Jun signaling axis, a key regulator in inflammation responses. This study highlights the possible role of A. clathratum in the inhibition of pro-inflammatory cytokines via suppression of the JNK/c-Jun signaling axis and suggests that A. clathratum could serve as a marine-derived anti-inflammatory agent in periodontitis.

A new commercial strain “Mongdol” of oyster mushroom was developed by hyphal anastomosis. It was improvedwith hybridization between monokaryotic strain derived from Pleurotus ostreatus ASI 0627 and dikaryotic strain derived from P.ostreatus ASI 2929. The optimum temperature of mycelial growth and fruiting body development were 25~30oC and 12~18oC,respectively. When two different media including PDA (potato dextrose agar medium) and MCM (mushroom complete medium)were compared, the mycelial growth of this mushroom was faster in MCM than in PDA. Similar result was observed with thecontrol strain P. ostreatus ASI 2504. Analysis of the genetic characteristics of the new cultivar “Mongdol” showed a different DNAprofile as that of the control strain ASI 2504, when RAPD (Random Amplified Polymorphic DNA) primer URP3 and URP6 wereused. Fruiting body production per bottle was about 106 g using demonstration farms. The color of pileus was blackish gray andthe stipe was long. Therefore, we expect that this new strain “Mongdol” will satisfy the consumer’s demand for high qualitymushrooms.

느타리는 한국에서 많이 재배되고 소비되는 버섯 중의 하나이다. 국내외에서 수집한 느타리 균주의 재배적 특성을 이용하여 모균주를 선발하였다. 품질이우수한 품종 ‘구슬(ASI 2018 x 수한 x 청풍)’을 수량이 다소 많은 품종 ‘야산(만추리 x 춘추2호)’과 교잡하여 수량이 많고 품질이 우수한 품종 ‘몽돌’을 2013년에 개발하였다. ‘몽돌’은 품질이 우수한 품종 ‘수한’의 대체 품종으로 병, 봉지 재배용 품종이다. ‘몽돌’은 균사배양은 23-25℃, 버섯 발생과 생육은 13-17℃가 알맞다. ‘몽돌’은 ‘수한’에 비하여 균사생장이 빠르고, 세균병에 강하며, 환기불량에 아주 강하고, 자실체 모양이 일정하고 안정성이 높으며, 고온에서 짙은 청회색으로 소비자 기호도가 높으며, 수확 시 자실체가 처진 버섯(하등품)이 거의 없는 품종이다. ‘수한’과 동일하게 환기를 많이 시키면 수한보다 키가 작고 갓만 커지므로 환기를 아주 적게 하여야 한다. 이산화탄소 CO2 농도가 800-15,00ppm 에서 품질이 양호한 편이다. 환기를 적게 하면 이산화탄소 농도가 높아져 ‘몽돌’은 키가 크고 수량이 증가하나 ‘수한’은 기형으로 나타난다. 재배 배지는 품종 ‘춘추2호’ 배지와 동일하거나 유사한 배지(톱밥 + 비트펄프 + 면실박 : 5 : 3 : 2)가 알맞다. 초기 생육이 다소 느리나 후기에 생육이 빨라 수확은 ‘수한’에 비해 0.5일 정도 빠르거나 유사하다. 수량성은 배지 종류와 환기량 등 환경조건에 따라 다르나 이 품종의 조건에 잘 맞으면 ‘수한’과 유사하거나 다소 높다. 이 품종은 2014년에 품종보호출원을 하였고 현재 통상실시 중이며, 특히 수확 시 처진 버섯이 ‘수한’은 5-10%이나 이 품종은 거의 없고 환기에 강하여 에너지 절감 효과가 크므로 농가의 경영비 절감과 보급 확대를 기대해 본다.

본 시험은 괘대재배를 한 ‘풍수’, ‘황금배’, ‘신고’, 그리고 ‘감천배’의 관행구와 무대재배를 한 과실에 TiO2나 Kaolin를 엽면처리 하였을 때 과실품질과 흑성병에 미치는 영향을 조사하고자 수행되었다. 1. 관행재배구는 TiO2나 Kaolin 보다 평균과중은 증가하였지만, 수량이 현저하게 감소하여 총 과실생산량은 감소되었다.2. 관행재배구에서의 ‘풍수’와 ‘감천배’의 당도는 TiO2나Kaolin 처리구 보다 높았다.3. ‘황금배’와 ‘감천배’의 과실 경도는 TiO2 처리시 가장 높았으며 Kaolin처리시도 다소 증가시켰다. ‘풍수’와 ‘신고’는 처리 간에 차이가 없었다.4. 과피색은 관행재배구에서 가장 밝은 색도를 보였다.5. TiO2와 Kaolin 처리는 품종에 상관없이 총 폴리페놀 함량을 증가시켰다.6. 엽의 흑성병 발생 억제율은 관행재배구가 ‘풍수’, ‘황금배’,‘신고’에서 낮게 나타났으며 ‘감천배’는 TiO2 처리로 100% 억제되었다.

노랑느타리는 한국에서 자생하는 버섯이나 자연 상태에서 흔하지 않다. 국내외에서 수집한 노 랑느타리 균주의 재배적 특성을 이용하여 모균주를 선발하였다. 수량이 많은 ASI 2978과 색 깔이 아름다운 품종 ‘금빛’의 단핵주간 교잡으로 교잡주를 얻었다. 계통간 교잡주 중에서 저온 에 강하고 색깔이 아름답고 수량이 많은 계통 Pc2011-23을 선발하여 품종심의회에서 ‘장다리’ 로 명명되었다. 품종 ‘장다리’는 특히 저온에 강한 편이다. 버섯 발생온도가 16~24℃로 저온에 서도 원기가 형성되어 생육한다. 생육 적온도 발생온도와 유사하나 19℃에서 품질이 양호하 다. 기존 품종인 ‘금빛’ 보다는 균사생장이 빠르며 자실체 수량도 다소 높다. 따라서 소규모 농가에서 느타리와 동일한 재배사에서 재배하는 농가에게 유리한 품종이다.