• The Korean Journal of Ecology
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• v.22 no.3
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• pp.163-167
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• 1999

In order to investigate territorial behaviour, Pungitius sinensis kaibarae were collected from Sacheon-river, Kangwon-do, Korea. They are reared in aquarium with designed experimental region from March to May 1996. In this study, territorial behaviour was divided into 1) pre-territorial movements of a shoal under varying water-weeds position 2) individual ranking patterns in connection with total length of fish 3) the change in size of territorial maps during the parental stage. The movements of a shoal tend to prefer regions with water-weeds and the lower half of the aquarium. Competition for territory was fierce, and fish that are longer in total length dominate smaller one in occupying territory. Both males and females developed territorial behaviour as they grew. However, male's territory was enlarged according to the hatching and dispersion of fry. At this time, aggressive tendencies reached their peak.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.735-742
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• 2003

In order to develop a logical method for using selective fishing gear, the behaviour and habits of the aquatic animals must be investigated. However, until now, little national research has been carried out to investigate the behaviour and habits of the common octopus (Octopus minor). The purpose of this study henceforth, is to compile necessary behavioral data to develop fishing gear to catch the common octopus. Behaviour and habits of the common octopus were observed while breeding in a water tank from February to May, 2003. The feeding habits of common octopus are more vigorous at night than in the daytime. The common octopus feeds on 1-4 bait crabs per day and consume each crab in 40-50 min. The sensory organs of the common octopus are more influenced by the sense of touch and smell, than by vision. Using live bait is more effective and advantageous than using dead bait, as the common octopus responded more to live bait. The hiding habits of the common octopus were very intensive, as they hid around all the shelters that were provided in this study. They demonstrated territorial behavior and struggled to maintain their sphere of influence. In addition, out of the various colors for shelters and bait supplied, the common octopus preferred light colors.

• Journal of Ecology and Environment
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• v.31 no.1
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• pp.17-21
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• 2008

Mating behaviour of the gammarid amphipod, Hyale rubra, was observed. H. rubra displayed precopulatory mate guarding: males clasped females with their gnathopods during copulation, forming a pair. Males also participated in embryo care during the incubation period. The population was small, and the sex ratio was almost equal. Energy allocation for mating effort and parental effort in the two sexes appear to be almost equal. The mating system was sequentially polygamous (or promiscuous) and there was conspicuous sexual dimorphism in the size of the gnathopod, which was used for mate guarding. However, there appears to be relatively weak sexual competition for mating opportunities despite conspicuous sexual dimorphism. H. rubra did not display territorial competition or external fertilization. Nevertheless, the male provided paternal care. Since H. rubra inhabit tide pools and live on algae, the polygamous mating system of the species can be explained by the polygyny threshold model. The evolution of mate guarding and parental care may have been favored by the species' low population density and harsh environments, an interpretation consistent with the optimality model.

• Journal of the Economic Geographical Society of Korea
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• v.20 no.3
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• pp.307-330
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• 2017

This paper attempts to elaborate on features of cross-border interaction conducted on Dan-dong, the main city of China-North Korea trade. Through the deep interview with some trader or firms and also questionnaire survey, this paper can reveal the supremacy of informal or non-market mechanism in the cross-border trade and inter-firm linkages, and also trader and firm's rent-seeking behaviour. These features show the uniqueness of border regime between China and North Korea. Even though it is getting more porous than before, I argue that China keeps the stance toward quite controlled borderland. As the proof of this argument, I show that main tenet of China's bordland policies is the borderland stability rather than the development. The striking one is the 'Prosperous Borders, Wealthy Minorities Program(??富民行???)'. In spite of the program's title, its utmost purpose is to secure the 'borderland stability and territorial integrity' rather than to enhance the border's openness and borderland's development.