• 한국수산과학회지
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• 제30권6호
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• pp.929-935
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• 1997

The total energy of fish movement and the maximum burst swimming speed were estimated and formulated in accordance with body length and water temperature for several species in fisheries by empirical methods and also by using published results. Under the assumption of swimming energy reserve of a fish at the initial rest state, the swimming endurance of fish with different body lengths, swimming speeds and angular velocity was calculated using the relevant equations under similar conditions in tank experiments as well as natural conditions in field. Relative swimming energy efficiency or the transition swimming speed between red and white muscle for energy consumption was represented as a trigonometric function of swimming speed ratio. Therefore, this model does closely approach the actual swimming abilities and their limits especially in relation to the fishing gear operation and allow for the greater vitality of the wild fish in the fields.

• 수산해양기술연구
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• 제44권1호
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• pp.10-19
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• 2008

This paper focuses on the mackerel's visual ability and swimming capability, and aims to describe the behavior in capture and escape process by trawl. The visual sensory systems and reaction behavior based locomotory capability were analyzed and simulated. The ability of fish to see an object depends on the light intensity and the contrast and size of the object. Swimming endurance of the fish is dependent on the swimming speed and the size of the fish. Swimming speeds of the fish are simulated 3 types of the burst speed, the prolonged speed and the sustained speed according to the time they can maintain to swim. The herding and avoiding is typical reaction of the fish to the stimuli of trawl gear in the capture process. These basic behavior patterns of the virtual mackerel to the gear are simulated. This simulation will be helpful to understand the fishing processes and make high selectivity of fishing.

• Fisheries and Aquatic Sciences
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• 제8권3호
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• pp.177-181
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• 2005

Fishing selectivity is determined by the level of voluntary escaping behavior in accordance with decision-making based on the relationship between fish size and mesh size. This study examined movement during the swimming behavior of black porgy in a trawl's towing cod-end and analyzed the movement components such as swimming speed, angular velocity of turning, and distance to the net over time. Most of the observed fish exhibited an optomotor response, maintaining position and swimming speed without changing direction. Others exhibited erratic or 'panic' behavior with sudden changes in swimming speed and direction. The latter behavior involved very irregular and aperiodic variations in swimming speed and angular velocity, termed 'chaotic behavior.' Thus, the results of this study can be applied to a chaotic behavior model as a time series of swimming movements in the towing cod-end for the fishing selectivity.

• 로봇학회논문지
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• 제4권1호
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• pp.43-48
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• 2009

Generally, underwater vehicle type of propeller shows low efficiency about 50%-55%. However, the efficiency of swimming mechanism of a fish is 60%-70%, more efficient about 20% than screw propellers. Recently, research of underwater vehicle type of fish increase due to its good efficiency and is regarded as a typical bio-mimical robot. In this research, a new algorithm and mechanism that show low energy consumption imitating swimming mechanism of fish proposed increasing speed and running time in field trial.

• 한국수산과학회지
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• 제46권3호
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• pp.273-281
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• 2013

The movement patterns of fish aggregations swimming freely near artificial reefs on August 24, 2006, at Suyeong Man, Busan, Korea, were acoustically investigated and analyzed. Acoustic surveys were conducted using a 70kHz split-beam echo sounder, 330 kHz side-scan sonar and a 310 kHz imaging sonar. Algorithms for tracking the movement of fish aggregations swimming in response to artificial reefs were developed. The travel direction and the swimming speed for two aggregations of fish were estimated from the trajectory orientations of echo responses recorded by the imaging sonar.The first group was floating just above the reef structure, while remaining in the midwater column, and the second group was swimming through and around artificial reefs near the seabed. The mean swimming speed was estimated to be 0.40 m/s for the midwater fish aggregation and 0.17 m/s for the bottom aggregation close to artificial reefs. These results suggest that the swimming behavior of fish aggregations passing close to artificial reefs near the seabed displayed a slower moving pattern than fish floating just above the reef structure in the midwater column.

• 수산해양기술연구
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• 제31권1호
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• pp.24-28
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• 1995

Exercise physiology of fish was studied by means of Electro-cardio-gram(ECG) technique with wired electrode system. Effects of swimming activity on the heart rate change for carp Cyprinus carpio was observed and analysed under swimming speeds among 1~3 Body Length/s and swimming durations of 10 and 60 minutes in the flume tank. The heart rate increase during swimming activity was observed in higher speed and longer duration conditions. The exercise effect on the heart rate continued even after fish stopped swimming. The time for recovery after exercise was tended to be elongated with the higher exercise condition.

• 생태와환경
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• 제52권2호
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• pp.118-125
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• 2019

어류의 유영능력은 어류의 생존을 결정짓는 중요한 요인이다. 또한, 어류의 유영능력 측정값은 어도 설치 시 서식하는 종에 대한 기초자료, 생태 하천 복원 시 어류의 서식 및 산란장 조성, 생태유량 산정 시 자료로 활용할 수 있다. 그러나 국내의 경우 담수어류의 유영능력에 대한 연구가 거의 이루어지지 않거나, 부족한 면이 있기 때문에 어류의 유영능력이 고려되지 않은 상태에서 어도들이 설치되어 왔다. 따라서 본 연구에서는 금강 수역에서 서식하는 붕어(Carassius auratus), 참갈겨니(Zacco koreanus), 줄몰개(Gnathopogon strigatus), 납자루(Acheilognathus lanceolata intermedia)를 대상으로 유영능력측정기 (Swim tunnel respirometer, $Loligo^{(R)}$ System)를 사용하여 돌진속도, 전진속도를 포함한 유영속도를 측정하였다. 종별 평균 돌진속도의 $U_{crit}$ (임계유영속도) 값은 붕어(C. auratus) $0.8{\pm}0.04m\;s^{-1}$; 참갈겨니(Z. koreanus) $0.77{\pm}0.04m\;s^{-1}$; 줄몰개(G. strigatus) $0.95{\pm}0.04m\;s^{-1}$; 납자루(A. lanceolata intermedia) $0.73{\pm}0.03m\;s^{-1}$으로 측정되었고, 각 종별 평균 전진속도의 $U_{crit}$ 값은 C. auratus $0.54m\;s^{-1}$, Z. koreanus $0.67m\;s^{-1}$, G. strigatus $0.7m\;s^{-1}$, A. lanceolata intermedia $0.54m\;s^{-1}$로 측정되었다. 본 실험에서 사용된 어류는 금강 수계에서 채집된 담수어류 중 4종만을 선정하여 실험이 진행되었기 때문에 한국의 전체 수계에 서식하는 해당 종을 대표하기에는 부족한 면이 있지만, 해당 수계에 서식하는 종의 특성 자료로 활용될 수 있을 것으로 판단된다. 따라서 향후 국내에 서식하는 보다 다양한 담수어류에 대한 유영능력 평가가 필요하며, 이들 자료를 활용한 어도를 통한 하천의 연결성 확보가 요구된다.

• Fisheries and Aquatic Sciences
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• 제5권3호
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• pp.206-211
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• 2002

The aim of this study was to obtain the basic data on the fish school behavior change to approaching vessel and fish species identification by means of their swimming speed. The surveys were carried out for the juvenile southern blue fin tuna and other fish schools off Esperance, western Australia from January to March 1999. We observed changes of fish school behavior in response to the approaching vessel using 360-degree scanning sonar. The results showed that, a horizontal direction index used to quantify a change of fish school behavior did not identify dependence of a radial distance and a swimming speed. A Mann­Whitney test conducted using the horizontal swimming speed of both species identified by sonar specialists, did not reveal a significant difference.

• 수산해양기술연구
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• 제59권2호
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• pp.125-134
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• 2023

The swimming behavior of pacific bluefin tuna (Thunnus orientalis) in the offshore sea cage of the brass fishing net was observed and analyzed by imaging sonar techniques. The cultured fish spent most of the time swimming a circular path along the circular cage wall and continued to swim only clockwise direction without completely changing the swimming direction during the 23-hour observation time. In addition, changed swimming behaviors were divided into four categories: (a) the behavior of a large group temporarily swimming in the opposite (counter clockwise) direction, (b) the behavior of a small group temporarily swimming in a small circular path, (c) the behavior swimming small circular path in the center of the cage, and (d) the behavior of a large group swimming across the center of the cage. The maximum swimming speed of the cultured fish was from 3.5 to 3.8 TL/s, the mode was from 1.2 to 1.4 TL/s and the swimming speed during the day time was faster than at night time. It was confirmed the cultured fish swam not only on the surface but also near the bottom net of the cage during the day, but swam mainly at the upper part of the cage at night.

• Fisheries and Aquatic Sciences
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• 제9권4호
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• pp.167-174
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• 2006

Two typical responses have been documented for flatfish when they encounter the ground gear of bottom trawls: herding response and falling back response. These two responses were analyzed from video recordings of fish and were characterized by time sequences for four parameters: swimming speed, angular velocity, acceleration, and distance between the fish and the ground gear. When flatfish displayed the falling-back response, absolute values of the three swimming parameters and their deviations were significantly higher than those during the herding response. However, the swimming parameters were not dependent on the distance between the flatfish and the ground gear, regardless of which response occurred. The dominant periods for most of the movement parameters ranged from 2.0 to 3.7 s, except that no periodicity was observed for swimming speed or angular velocity during the falling-back response. However, variations in the four parameters during the falling -back response revealed greater irregularity in periodicity and higher amplitudes. This complex behavior is best described as a chaos phenomenon' and is discussed as the building block for a model predicting the responses of flatfish to ground gear as part of the general understanding of the fish capture process.