• The Korean Journal of Zoology
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• v.20 no.2
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• pp.67-76
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• 1977

The periodic changes of testis and \ulcorner션 epididymidis in Korean hibernating bats, the oriental discoloured bats (Vesportilio superans Thomas) and the Korean greater horseshoe bats (Rhinolophus ferrumequinum korak Kuroda) were studied in order to clarify the possibility of correlation between their histological findings and one of physiological facets, hibernation, and the results obtained were as follows: 1. The spermatogenic function of the oriental discoloured bats obtained in July and August was depressed although the spermatocytes showed a considerable cell proliferation. Few mature sperms were observed in the seminiferous tubules of the bat obtained in August. 2. The spermatogenic function of the Korean greater horeshoe bats obtained in September was not remalkable but a considerable number of sperms were stored in the excretory ducts which were characterized by existence of para-tubular spaces in the ductus epididymidis. 3. The spermatogenic epithelia of the Korean greater horseshoe bats obtained in December showed histologically atrophied figures. However, a vast number of sperm remained in extremely expaned luminae of the ductuc epididymidis which epithelial cells were maintained rectangular in shape. 4. These results suggest that there are periodic changes of the spermatogenic epithelia and the excretory ducts, and that those histological changes are closely related to their wintering.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.676-685
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• 2003

Seasonal variation of the fishery resource in the shallow waters of Ganghwado tidal flat was investigated using monthly collected samples with a fence net from June 1998 to May 1999. Thirty-six species were found including 27 fish species, 6 crustaceans, and 3 molluscs. Of the fish, Konosirus punctatus, Sardinella zunasi Liza haematocheila and Synechogobius hasta dominated in the number of individuals $(92.1\%)$ and in biomass $(94.5\%).$ A few number of resident species, such as L. haematocheila and S. hasta, were collected only during the cold months. As the water temperature increased in the spring, the adult migratory fish such as K. punctatus and S. zunasi, were collected. In the summer, the juvenile fish recruited in the shallow water showing a peak in fish abundance. The data suggested that they grew until late autumn before moving to deeper waters for over-wintering. The principal component analysis showed that the seasonal variation in species composition was principally determined by water temperature and/or water temperature related factors. The species composition of the fish assemblage in the study area suggested that these species are highly adapted to extreme seasonal temperature variation and high water turbidity.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.3
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• pp.578-586
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• 2014

The seasonal appearance and distribution of finless porpoise (Neophocaena asiaeorientalis) was investigated with sighting survey method around Wido in West sea, Korea. Fishing survey with drag net was also conducted to investigate the species composition of inhabitants and the consignment quantity data of fisheries cooperation was collected to confirm the seasonal change of the composition and quantity of them. Finless porpoise didn't emerged around Wido in winter season, but the number of appearance in summer season amounted to 1~15 indv. for 15 observing points and the appearance frequency became lower in open sea than in inshore. There was also significant relationship between the appearances of finless porpoise (Neophocaena asiaeorientalis) and that of inhabitants. we consequently concluded that finless porpoise typically distributes from April to september, and moves to another area for wintering and food consumption from October to March.

• The Korean Journal of Ecology
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• v.24 no.4
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• pp.219-222
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• 2001

The study was conducted to get the basic information for proper protection and management of black-faced spoonbill and their habitats in western coast of South Korea. The species was observed in 8 sites of western coast of South Korea in spring 2000. We confirmed breeding of this species at least 4 pairs in Seokdo island. This island is considered likely to be an imortant breeding site together with Yodo island, Hambakdo island and Yokdo island. Also, we observed breeding of herring gull in Seokdo island and small island nearby Boleumdo island for the first time in South Korea. Chilsando island, Cheonsuman bay and Gyeokyeolbiyeoldo island were considered as stopovers located on the Korean Peninsula route. The other sites were considered as summering sites of the black-faced spoonbill. Especially the birds were constantly observed from breeding season to postbreeding season in Seonduri and Yeochari of Ganghwado island. We have counted maximum 88 individuals gathered at Gaksiyeo in Seonduri and Yeochari on September 3, 2000. The species seemed to gather at these sites after breeding for migration to wintering ground in September. We also surveyed changes of the number of individuals as time of the ebb and flow on September 3 and 6, 2000, their time budgets were affected by the ebb and flow in these sites.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.1
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• pp.39-54
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• 2005

Seasonal variation in species composition of fish in the Geum River estuary was determined using monthly samples collected with a bag net from February to December 2003. Of a total of seventy-three species collected, four groups of fishes were distinguished. Estuarine fishes such as Chelon haematocheilus and Synechogobius hasta were collected almost all the seasons and predominated in abundance during cold months. Coastal fish species such as Sardinella zunasi, Konosirus punctatus, Engraulis japonicus, Johnius grypotus and Thryssa kammalensis were dominated from late spring to autumn. Their adults entered into the estuary in spring and a large number of their juveniles were collected in summer and autumn till moving out to deeper waters for over-wintering. A few freshwater fishes were collected when the freshwater was discharged during the rainy season. Anguilla japonica elvers (diadromous fish) and Coilia nasus (amphidromous fish) were collected in spring during their upstream migration. The principal component analysis revealed that the seasonal variation in species composition of fishes was principally determined by water temperature and/or water temperature related factors.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.3
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• pp.158-164
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• 2019

We examined the adaptability of Korean winter forage crops such as Italian ryegrass, barley, oat, and triticale in Uzbekistan. The overall growth before wintering was slightly different between Uzbekistani and Korean varieties, but there was no significant difference among winter forage crops. The heading date of the Korean triticale 'Shinyoung' was the earliest, (April 4), and the heading date of the Uzbekistani triticale 'Frack cerebristy' was quite late, (April 25). The heading date of the Korean Italian ryegrass 'Kowinearly' was four days earlier than that of 'Kowinmaster,' on April 13, and that of the Korean barley 'Youngyang' and 'Yuyeon' were five days earlier than that of the Uzbekistani barley 'Bolgaly'. The maximum dry matter yield of winter forage crop was from Uzbekistan triticale, 'Frack cerebristy', which was 13,536 kg/ha. The dry matter yield of Uzbekistan barley was 8,222 kg/ha. Compared with Uzbekistan barley, 'Bolgaly', yields of Korean barley 'Youngyang' and 'Yuyeon', Korean oat 'Samhan', and Korean Italian ryegrass 'Kowinearly' and 'Kowinmaster' were 59~64%, 125%, and 113~133%, respectively.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.4
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• pp.285-292
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• 2021

We investigated habitat use and home range of a rescued and released white-naped crane using GPS tracking technology in Cheorwon, South Korea, from October 2016 to March 2017. Four types of roosting sites were identified: frozen reservoirs, paddy fields, rivers, and wetlands. Upon arrival, the white-naped crane preferred wetlands in the Demilitarized Zone (DMZ). In late wintering season, it showed a tendency to change main roosting sites in the following order: rice paddies, rivers, and frozen reservoirs. Among 14 sleeping places, Civilian Control Zone (CCZ) with various type of available habitats was more preferred than the DMZ. Places outside of CCZ were rarely used due to anthropogenic disturbances during the night. The tracked white-naped crane widely chose daytime feeding sites while moving around all over rice paddies in the CCZ. Mean diurnal movement distance was 10.5 km with a maximum of 24.8 km. Its home range measured with Minimum Convex Polygon (MCP) and Kernel Density Estimation (KDE) was 172.30 km² with MCP, 159.60 km² with KDE 95%, 132.48 km² with KDE 90%, and 42.45 km² with KDE 50%. All estimated values of home ranges were higher in the early and later winter than those in the middle period.

• Korean Journal of Organic Agriculture
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• v.31 no.4
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• pp.441-451
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• 2023

Golden apple snails (Pomacea canaliculata) were first introduced as food for high protein source and were later widely used as a means of weeding in rice paddies by taking of their vigorous feeding habits. Since 2000, the wintering of golden snails has been found and damage to rice plants occurred by them. To prevent damage, a means to control golden apple snails has become necessary. In this study, we investigated the possibility of eco-friendly control of golden apple snail by using Styrax japonicus fruit that grow naturally in-country. When the ethanol extract of the fruit was treated for controlling golden apple snail, the effect of over 90% was confirmed at 250 and 125 ppm after 1 day. Using UPLC MS analysis, two major compounds, dihydrorotenone known as a natural pesticide was detected. The molluscicidal activity was confrimed at 50 ppm of dihydrorotenone standard material. Our results showed that the possibility of developing an eco-friendly agent of golden apple snail using S. japonicus fruit was confirmed.

• Journal of Veterinary Clinics
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• v.41 no.3
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• pp.189-194
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• 2024

Cinereous vulture (Aegypius monachus) is a large raptor that belongs to the family Accipitridae in the order Falconiformes. It is a migratory bird that returns to Mongolia after wintering in the Korean Peninsula. In February 2015, a cinereous vulture was rescued from Asan-si, Chungcheongnam-do Province as it could not fly. It was transferred to the Chungnam Wild Animal Rescue Center in Korea. It was found to have a closed fracture on the right radius through radiographic examination, a basic procedure. Surgery was performed at the fracture site using a shuttle pin and wire. After successful physical therapy and rehabilitation, the cinereous vulture was released in October 2015. A metal ring (150-00713) and wing tags (G/BL 3) were attached to the bird before its release for subsequent identification. Two years and 4 months later, in March 2018, the cinereous vulture was rescued and brought back to the center. It was diagnosed with secondary pesticide poisoning. After receiving treatment, a radiography test revealed no specific findings related to the previous fracture surgery. Considering that migratory birds travel long distances, it was confirmed that the treatment for reducing the fracture in the radius using a shuttle pin and a cerclage wire was suitable.

• Korean Journal of Organic Agriculture
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• v.19 no.2
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• pp.255-272
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• 2011

This work studied the growth and yield of green crops, changes of mineral composition in greenhouse soil and green crops, and infection with wintering green crops cultivation in greenhouse field. At 74 days after seeding of wintering green crops, dry matter was 710kg/10a in rye, 530kg/10a in barley, 230kg/10a in hairy vetch, and 240kg/10a in bean or weeds. Total nitrogen content in green crops was 4.5% in pea and hairy vetch, and 3~4% in barley and rye. $P_2O_5$, CaO, and MgO contents in all green crops were about 1.0%, and $K_2O$ content was the highest level by 4~5% among macro elements. Total nitrogen fixing content in shoot green crops uptaken from soil was 22.1kg/10a in rye, 20.6kg/10a in barley, 10.6kg/10a in hairy vetch, and 9.6kg/10a in pea and giant chickweed. $P_2O_5$ fixing content in shoot green crops uptaken from soil was 8.4kg/10a in rye, 6.3kg/10a in barley, and 2.3 kg/10a in hairy vetch and pea. $K_2O$ fixing content in shoot green crops uptaken from soil was 28kg/10a in rye, 24.7kg/10a in barley, and 11kg/10a in hairy vetch and pea. CaO fixing content in shoot green crops uptaken from soil was 2~3kg/ 10a in all green crops, and MgO fixing content was 1.7~2.6kg/10a in all green crops. Pepper growth in no-tillage was not a significant difference at all green manure crops. The number of fruit and fruit weight were higher in control, pea, hairy vetch and harvest barley than rye and barley. Soil mineral compositions in wintering green crops increased at pH, organic matter, CEC compared with control. Soil chemical compositions were stable level at green crops cultivation according as decreases of EC, available phosphoric acid, Ca, and Mg contents. After no-tillage by green manure crops, pH in soils was higher in green manure crops than control. EC content in soils was lower in green manure crops than control, and was remarkably low level in barley harvest. Organic matter content in soils increased in hairy vetch and barley green manure but decreased by 35% in barley harvest. Total nitrogen and avaliable $P_2O_4$ content in soils remarkably increased but was not a significant difference at all green manure crops. Cation (K, Ca, and Mg) content in soils decreased by 15~20% in K, 2~11% in Ca, and 3~6% in Mg at rye, barley and pea compared with control.