• Korean Journal of Environment and Ecology
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• v.33 no.2
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• pp.168-177
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• 2019

This study was conducted to examine the impact of various environmental factors on the feeding behavior of black-faced spoonbills Platalea minor known to use rice fields during the breeding season. We surveyed the rice fields three times a month from April to June 2017 and from April to June 2018. We counted the number of black-faced spoonbills and measured the environmental factors such as the water depth, paddy type by cultivation stage, and biomass of potential prey that are expected to affect black-faced spoonbills. We also filmed the feeding behavior of black-faced spoonbills to examine differences in feeding behavior by environmental factors. The survey showed that the number of black-faced spoonbills reached its peak from late April to late May which was the breeding period. Among a total of 308 black-faced spoonbills observed, 86.4% (n=266) were observed feeding on rice paddies, 90.6% (n=279) were adults, and none was observed on dry paddies. The biomass of rice paddy increased significantly since May when fish started hatching, and there was a significant difference in the amount of biomass between the rice paddies where black-faced spoonbills were observed and other rice paddies. The analysis of the feeding behavior of black-faced spoonbills showed that the feeding efficiency and feeding success rate of black-faced spoonbills increased significantly when the amount of biomass soared and that the number of steps of black-faced spoonbills per minute increased greatly after rice planting was completed. The number of bill sweeping was not related to the feeding efficiency, feeding success rate, and paddy type by cultivation stage.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.85-89
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• 2012

To investigate the bird's dieting behavior for several fruits in orchards, this study was carried out in 2008. Black-billed magpies (Pica pica), azure-winged magpies (Cyanopica cyanus), and brown-eared bulbuls (Hypsipetes amaurotis) made their unique marks on the surface of pear and apple fruits; black-billed magpies pecked fruits strongly and left round holes with perpendicular angle, whereas those of azure-winged magpies and brown-eared bulbuls were sack-shaped with narrow neck and marked unique stripes on the skin. For the fruits of pear and apple from bagging practices, the birds showed different foraging behavior; black-billed magpies could injure all kinds of fruits whether with paper bags or not, but azure-winged magpies and brown-eared bulbuls could not attack the fruits with paper bag. Azure-winged magpies and brown-eared bulbuls preferred pear fruits to those of apples and satsuma mandarins in the cage trials. To reduce the injuries by azure-winged magpies and brown-eared bulbuls on pear and apple fruit, wrapping bag should not be impaired. Introducing azure-winged magpies to Cheju should be prohibited for the potential citrus injury by them.

• Journal of Wetlands Research
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• v.12 no.1
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• pp.41-49
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• 2010

Web building of the spider is an investment behavior for prey foraging with genetic constraint. Individual's decision-making on the web construction depends on diverse environmental variables. This study investigated web structure of the wasp spider, Argiope bruennichi, to compare individual's behaviors in dry field and in wet field. We measured 35 web structures in dry field (Chunma-San, Incheon) showing relatively low humidity (46.4%) and luxuriant herbage, and 13 web structures in the wet rice field (73.9%; Taean-Gun, Chungnam). Comparing to the wet field the individuals in the dry field invested significantly more silk: $32.5{\pm}12.8$ number of silk spirals used in the dry field vs. $16.9{\pm}5.4$ in the wet field. The web area of the dry field was greater than that of the wet field: $976{\pm}643cm^2$ vs. $532{\pm}254cm^2$. The web height, distance between the ground and the center of the web, appeared higher in the dry field than in the wet field: $71.4{\pm}39.6cm$ vs. $49.6{\pm}31.2cm$. Also the web constructed in the dry field showed longer stabilimentum than the web of the wet field: $18.8{\pm}3.4cm$ vs. $3.9{\pm}3.2cm$. The perpendicular inclination and the inclination to East-West of the web showed no difference between the two fields. This study suggests that adult females of A. bruennichi could modulate its construction behavior depending on the micro-habitat factors.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.4
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• pp.1-14
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• 2013

A species restoration plan requires a process where the first is to thoroughly study the target species, second is to provide them with an onsite reproduction and adaptation period, and finally, third is to release them to their natural habitat. This study focuses on the space planning for target species' successful onsite reproduction and adaptation. For the study, a site planning near Sobaeksan National Park was implemented with Red Fox's behavior and habitat characteristics in mind for its recovery, reproduction, and natural adaptation. During site selection and planning, the basic aim was to incorporate the existing site as much as possible thus reducing the impact on the environment from the recovery plan. In addition, for a stable recovery of the Red Fox population, the site was classified into three different areas : core area, buffer zone, and transition area. Then, the facilities that help Red Fox's reproduction and adaptation such as reproduction center, foraging site, adaptation training center were planned. Under the condition that the site will be off limit to the public, a limited number of paths for monitoring was provided. For the site's vegetation, the existing species were planted as much as possible with the addition of plants that the Red Fox consume. The facilities included as Red Fox's habitat were fox burrows for hiding and ecological ponds for drinking. From this study, the recovery of the endangered fox species is expected as well as the contribution to an effort to increase of awareness toward the biological resources in Korea through Nagoya protocol. Furthermore, it has the potential to change the public's attitude toward endangered species recovery projects through publicizing and providing experience to the national park visitors.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.3
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• pp.316-324
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• 1995

Ecology and life History of the mudskipper, Boieophthaimus pectinirostris were investigated based on the specimens collected from the Korean roasts from 1978 to 1994. The spawning of this species takes place during the period from June to August. Prolarva hatched from egg was 3.3mm in total length, and began to bottom life in TL 16.0mm of 40 days after hatching. The stomach contents were principally diatoms. In the foraging behavior, this species were conducted at the wet soft mud on the upper tidal zones. The burrowing observed in the intertidal mud flat was YL type. B. pectinirostris is restricted to western and southwestern coast of Korea, but their habitats and individuals are being reduced by the result of reclimation to tide land.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.1
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• pp.64-76
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• 2017

Routing in mobile ad hoc networks (MANETs) is highly challenging because of the dynamic nature of network topology. AntHocNet is a bio-inspired routing protocol for MANETs that mimics the foraging behavior of ants. However, unlike many other MANET routing protocols, the paths constructed in AntHocNet are unidirectional, which requires a separate path setup if a route in the reverse direction is also required. Because most communication sessions are bidirectional, this unidirectional path setup approach is often inefficient. Moreover, AntHocNet suffers from looping problems because of its property of multiple paths and stochastic data routing. In this paper, we propose a modified path setup procedure that constructs bidirectional paths. We also propose solutions to some of the looping problems in AntHocNet. Simulation results show that performance is significantly enhanced in terms of overhead, end-to-end delay, and delivery ratio when loops are prevented. Performance is further improved, in terms of overhead, when bidirectional paths setup is employed.

• Journal of Ecology and Environment
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• v.43 no.2
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• pp.263-270
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• 2019

Background: The gelada baboon, Theropithecus gelada Ruppell, 1835, is an endemic primate of the central and western highlands of Ethiopia occurring between altitudes of 1800-4400 m. Variability in activity time budget between the two gelada social units, i.e., one-male units (OMUs) and all-male units (AMUs), has not been studied previously. Thus, the present study was an effort to understand intra- and inter-variations in group size and daily activity time budget in gelada baboon OMUs and AMUs at Guassa Community Conservation Area, Central Ethiopia. The instantaneous sampling method was used in the data collection. Results: Both OMU and AMU groups allocated more time for feeding (OMUs = 36.96%; AMUs = 35%) followed by moving (OMU = 25.8%; AMUs = 27%). Grooming was the most frequent social activity in both family groups (OMUs = 8.56%; AMUs = 11.81%). OMUs and AMUs did not show significant variation between themselves in the time budget and temporal distribution of their daily activities. However, the overall variation in the time budget allocated for daily activities within OMUs and AMUs was statistically significant (p < 0.05%). The different age and sex groups in OMUs (i.e., immature, sub-adult females, subordinate males, adult females, and alpha males) showed statistically significant variation in their time budget allocation for the daily activities (p < 0.05) except for feeding and moving. Alpha males had the highest proportion of resting (32.14%) and aggression (31.92%). Immature individuals were responsible for > 90% of the time budget recorded for playing while adult females showed the highest frequency of grooming. Group size of OMUs ranged between 5 and 15 individuals (mean ± SD = 11.25 ± 1.95). Adult females comprised the highest number within OMUs (mean = 4.5) followed by immature individuals (mean = 3). The group size of AMUs ranged from 4 to 8 (mean ± SD = 6.6 ± 1.5). Conclusion: Our results showed that the gelada baboon spent less time on foraging compared to previous studies at the Simien Mountains and Debre-Libanos area. We suggested this variation could be explained based on higher forage quality at Guassa Community Conservation Area resulting from better conservation of the habitat.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.21 no.3
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• pp.151-163
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• 2010

It is necessary, due to changes in the information environment, to investigate problems in existing information retrieval systems. Ontologies and social tagging, which are a relatively new means of information organization, enable exploratory discovery of information. These two connect a thought of a user with the thoughts of numerous other people on the Internet. With these connection chains through the interactions, users are foraging information actively and exploratively. Thus, the purpose of this study is, through qualitative research methods, to identify numerous discovery facilitators provided by ontologies and social tagging, and to create an exploratory discovery model based on them. The results show that there are three uppermost categories in which 5, 4 and 4 subcategories are enumerated respectively. The first category, 'Browsing and Monitoring,' has 5 sub categories: Noticing the Needs, Being Aware, Perceiving, Stopping, and Examining a Resource. The second category, Actively Participating, has 4 categories: Constructing Meaning, Social Bookmarking and Tagging, Sharing on Social Networking, Specifying the Original Needs. The third category, Actively Extends Thinking, also has 4 categories: Social Learning, Emerging Fortuitous Discovery, Creative Thinking, Enhancing Problem Solving Abilities. This model could contribute to the design of information systems, which enhance the ability of exploratory discovery.

• Journal of Apiculture
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• v.34 no.3
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• pp.189-195
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• 2019

Plants release a large variety of volatile organic compounds (VOCs) into the surrounding atmosphere. Floral volatile compounds (FVCs) emitted from many plants is the critical factors for pollinator attraction and defense for adaptation in environments. Recent studies indicate that the chemical components contributing to FVCs play an important role in the honeybee attractiveness to flowers. Olfactory signals are rapidly learned, indicating that foraging behavior results from the association of plant chemicals acting as chemosensory cues for the bees. Solid phase microextraction(SPME)-GC/MS method was applied to analyze the chemical composition of FVCs according to the different species of Robinia spp. The abundant compounds identified in R. pseudoacacia were (Z)-β-ocimene (34.86%) and linalool (35.47%). Those of the tetraploid R. pseudoacacia were (Z)-β-ocimene (35.42%) and α-Farnesene (33.94%). The volatiles of R. margarettae 'Pink Cascade' comprised an abundance of (Z)-β-ocimene (42.73%), (E)-4,8-Dimethylnona-1,3,7-triene (37.23%). Differences in FVCs of the different species of Robinia spp. are discussed in light of biochemical constraints on volatile chemical synthesis and of the role of flower scent in ecology of pollination.

• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.21-30
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• 2005

Feeding behavior of foraging ants including visiting numbers, species, and preference on insect cadavers killed by entomopathogenic nematodes <(Heterorhabditis sp. KCTC 0991BP (He) and Steinernema carpocapsae KCTC 0981BP (Sc)> and their symbiotic bacteria was investigated in Dongrae Benest Golf Club, Anyang Benest Golf Club, Gapyung Benest Golf Club and Ulsan Golf Club. The number of ants, kinds and numbers of cadavers taken away by ants were different depending on killing method, golf club and site within the golf courses (fairway and rough). The feeding preference of ants was the lowest on cadavers killed by He. At Dongrae Benest Golf Club Lasius japonicu ($75{\pm}5\%$) and Monomorium floricola ($10\%$) took away cadavers only at the rough. The visiting rate of ants was $85{\pm}6\%$ at the rough, but none at the fairway by 16 hours. The taken rate of cadavers by ants was the lowest on He-killed cadavers representing $16.7\%$ compared with $40.0\%$ on Sc-killed cadavers, $53.3\%$ on fenitrithion-killed cadavers, and $56.7\%$ on natural dead cadavers by 12 hours. At the rough of hole 6 in Anyang Benest Golf Club, Tetramorium tsushimae ($33{\pm}12\%$), Pheidole fervida ($17{\pm}15\%$), Camponatus japonicus ($10\%$), Formica japonica ($7{\pm}6\%$), Paratrechina flavipes ($3{\pm}6\%$), and Crematogaster matsumurai ($3{\pm}6\%$) took away cadavers, but $23{\pm}15\%$ of cadavers were not visited by ants. Ants took away $40\%$ of Sc-killed cadavers, $16.7\%$ of frozen-killed cadavers, and $3.4\%$ of He-killed cadavers. The number of visiting ants was low at the hole 9 of Cherry course in Gapyung Benest Golf Club and only Tetramorium tsuhimae and Paratrechina flavipes were found from one site. The density of entomopathogenic nematodes did not influence ant visiting on cadavers, but burying affected ant visiting. Although ants took away unburied cadavers, buried cadavers were taken away at the hole 6 of Dongrae Benest Golf Club by 16 hours. Ant visiting had the same tendency on symbiotic bacterium-treated biscuit as nematode-killed cadavers. The visiting was less on biscuit inoculated by Photorhabdus sp., a symbiotic bacterium of He than on biscuit inoculated by Xenorhabdus nematophila, a symbiotic bacterium of Sc.