• Asian-Australasian Journal of Animal Sciences
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• v.29 no.3
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• pp.428-435
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• 2016

The objective of this study was to clarify the most effective component of grazing for improving welfare of fattening pigs. This study compared welfare indicators of 20 fattening pigs aged 100 to 124 days (the prior period) and 138 to 164 days (the latter period) in an indoor housing system (IS), an outdoor pasturing system (OP), a concrete floor paddock system (CF), a concrete floor paddock system with fresh grass (FG), or a soil floor paddock system (SF). The last three treatments include important components of a grazing system: extra space, grass feed, and soil floor. Behavior, wounds on the body, and performances, measured as average daily gain (ADG) and feed conversion ratio, were observed. CF pigs behaved similarly to IS pigs. FG pigs showed higher levels of foraging, chewing and activity. SF pigs engaged in higher levels of foraging, exploring, activity, and rooting, and showed a similar amount of playing behavior as OP pigs. ADG was the same in all treatments at the prior period, and increased in the order FG, IS, CF, SF, and OP at the latter. The behaviors and performance of SF pigs resembled those of OP which seemed to indicate a consistently higher standard of welfare than the other treatments. In conclusion, the existence of a soil floor is the most important component of a pasture for improving the welfare of pigs.

• Journal of Apiculture
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• v.33 no.4
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• pp.239-250
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• 2018

We investigated the pollination activity of honeybees (Apis mellifera L.) in terms of different climatic conditions in the greenhouse cultivation of watermelons (Citrullus lanatus L.) during winter. The aim of the study was to search a climatic condition which effectively can be use honeybees as pollinators during the flowering season of watermelons in winter or early spring. The average climatic conditions inside the greenhouse during the bee activity time (BAT)-between 10:00 and 16:00 in mid-Februarywere a temperature of $30.4^{\circ}C$, relative humidity of 53.7%, illuminance level of 22,728.4lx, and UV level of $0.233mW/cm^2$. Bee traffic and foraging activity were at their greatest at 10:00 and tended to decrease with time. Male watermelon flowers typically dehisced between 10:00 and 12:00. Climatic conditions were significantly correlated with bee activities, including bee traffic and foraging activity. Bee activities were positively correlated with temperature, illuminance level, and UV level but negatively correlated with relative humidity. Temperature had the greatest effect on honeybee behavior. Among the foraging honeybees, the number of high-flying bees that did not pollinate flowers showed a strong positive correlation with temperature, and the number of bees landing on the flowers showed a positive correlation with the UV level. The temperature range inside greenhouses at which the pollination activities of honeybees can be maintained efficiently during winter watermelon pollination was found to be $21{\sim}25^{\circ}C$.

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.147.2-147
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• 1999

No Abstract, See Full Text

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2007.04a
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• pp.176-177
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• 2007

We determined how presence of heterospecific individuals in the vicinity of a focal individual affects the behavior of two critically endangered species of cranes on their wintering grounds at Cheolwon in the Korean Demilitarized Zone(DMZ). The Red-crowned crane, Grus japonensis, is larger than the White-naped crane, Grus vipio, and it dominates the White-naped crane in aggressive interactions. We showed that the dominant species increases foraging activity in the presence of the subordinate species presumably because of scrounging of the food from the subordinate. Because interspecific interactions may affect avian endangerments this behavioral findings should be taken into account when managing winter refuges for the two engendered crane species.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.483-492
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• 2019

During the breeding season, both adults and immature Eurasian Oystercatchers (Haematopus ostralegus osculans) were observed to feed on prey, such as gastropods (Umbonium thomasi) and bivalves, at the tide water line around Yubu island in Korea. To determine differences in the foraging efficiency between the adult and immature birds, we recorded the feeding behavior using digiscoping with a telescope and a smartphone. We compared the pace, the prey search rate, the proportion of prey search techniques, the feeding success rate, the handling time, and the heads-up rate between the adult and immature birds. There were significant differences in the proportion of prey search techniques when gastropods were consumed and in the prey search rate and heads-up rate when bivalves were consumed but there were no significant differences in feeding success rates. Therefore, although the immature birds on Yubu Island were inferior to adults during the breeding season and they lacked the proficiency to locate prey, their overall foraging efficiency was similar to adults. This was considered to be due to the continuous eating of bivalves during the wintering season, which requires a high level of foraging efficiency.

• Journal of Wetlands Research
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• v.13 no.1
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• pp.139-148
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• 2011

Web structure of spiders is a foraging strategy as well as an investment to get prey. In order to make a good foraging decision spiders should change its foraging strategy in the basis of sensory information provided by potential prey species. We conducted experiments to demonstrate whether a wasp spider, Argiope bruennichi modifies its web-building behavior after experiencing sensory information emitted by a cricket species, Teleogryllus emma. To know how the web structures would be modified, we quantified web characteristics after providing sensory information of the cricket and compared to the control group. Web construction decreased in the course of the experiment in both, control group(without stimulus) and experimental group(with stimuli). The results did not show remarkable differences between two groups. However, on the first day after providing sensory information of the cricket, the web-building behavior of A. bruennichi decreased only in 3.7% of the experimental group individuals against 11.8% of the control group individuals. The number of the stabilimentum constructions decreased overall in both groups. On the first day the decreasing proportion was doubled in the control group(14.7%), comparing to the experimental group(7.4%). The individuals did not lower its web height and did not extend its web area according to sensory information of the prey.

• Molecules and Cells
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• v.25 no.1
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• pp.50-54
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• 2008

The vesicular glutamate transporter (VGLUT) transports glutamate into pre-synaptic vesicles. Three isoforms of VGLUT have been identified in humans, but their functional differences remain largely unknown. EAT-4 is the only homologue of human VGLUT in C. elegans. Here we report that mutants of eat-4 exhibit hyperforaging behavior and that each of the isoforms of human VGLUT functionally rescues the defects in eat-4 worms.

• Journal of Korean Society on Water Environment
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• v.21 no.1
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• pp.79-83
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• 2005

Foraging behaviour of false dace, Pseudorasbora parva, was investigated in water flowing at various velocities with the existence of a cavity for rest. The pursuit comprised three succeeding processes such as, approaching, chasing and attacking. Angles between the fish body and the water flow direction and swimming speeds increased in the latter stages of approaching, chasing and attacking. All pursuit angles, swimming speeds and distances increased with flow velocity and peaked at the flow velocity of 7 cm/sec. At higher velocities, however, the fish avoided the use of much energy against the large drag force. The probability of capture and the feeding rate steadily decreased with increasing flow velocity. Under the fast flow, the fish adjusted their swimming speed to get the optimum velocity relative to the flowing water for the energetic budget. Fish spent more time in the cavity as flow velocity increased to avoid the energy expenditure necessitated by the high velocity.

• Journal of Environmental Impact Assessment
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• v.24 no.5
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• pp.532-548
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• 2015

The winter ecology of individual yellow-throated martens(Martes flavigula) intemperate region of Korea were studied through snow-tracking. The study was performed across 3 winter seasons, from January 2011 to February 2013. Total distance of 49.8km was snow tracked (comprising 13 snow-tracking routes) to determine winter foraging habits, general behavior and movement paths of solitary and small groups (1-6 individuals; $mean=2.9{\pm}1.6$) of yellow-throated martens. The martens in the current study were omnivorous, with their winter diet including 9 animal and 5 plant species. Yellow-throated martens searched for food near and under the fallen logs and branches, root plates of fallen trees, around the roots of growing trees, and in small holes in the ground. They also climbed trees to search inside the tree holes and vacant bird nests. Foraging activity was estimated to occur at a frequency of 1.20 times/km, while territory marking occurred 1.42 times/km on average. Of the 60 documented foraging activities we observed, 17 were successful (28.3%). Moving activity and territory marking mainly occurred along ridges, whereas foraging activity was recorded in valleys, slopes, and forest edges. To protect the habitat of this species, the entire forest should be preserved, including the valleys, slopes, and even forest edges as well as main ridges.

• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.178-185
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• 2015

BACKGROUND: The coexisting shorebirds often use various foraging strategies, including feeding methods and habitat use, which are the likely mechanisms to explain the variation of morphological and behavior traits. We studied the foraging behaviors of four shorebirds to define how species separate according to habitat structures in rice fields of western-central Korea during their northward migration. METHODS AND RESULTS: The studied species were Long-toed Stints (Calidris subminuta), Wood Sandpipers (Tringa glareola), Common Greenshanks (Tringa nebularia), and Black-tailed Godwits (Limosa limosa), which were commonly observed in rice fields and represented by a wide range of morphological traits. Habitats were categorized into three types ("plowed with water", "shallow water level after harrowing", and "deep water level after harrowing") according to the irrigation intensity and soil manipulation of the farming practices. Long-toed Stints mainly foraged in the "plowed with water", where they used both visual and tactile searching methods. Wood Sandpipers and Common Greenshanks were frequently observed in "shallow water level after harrowing" They spent a considerable amount of time using a visual searching method. Black-tailed Godwits were selectively attracted to "deep water level after harrowing" and used tactile cues as their predominant feeding technique. CONCLUSION: This study demonstrates that the water levels related in soil manipulation and irrigation intensity influence the accessibility to foraging sites and the detectability of prey for shorebirds species.