• Journal of Wetlands Research
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• v.14 no.3
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• pp.413-418
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• 2012

In this study, both habitat use analysis by rumen contents of Eurasian river otter (Lutra lutra) were carried out to investigate the preference of habitat environment and diet using their fecal samples. As the target sites, two streams (the Naechon-cheon and the Koonup-cheon) were selected in the upstream of the Hongcheon river, Hongcheon County, Gangwon Province. A total of 478 track samples (e.g., feces, scent and footprint) were found during the survey periods (May to November, 2009 and November, 2010). The dominant points, where the tracks of river otters were observed, were areas with the low depth(0.5-1m) and the slow flow velocity (5m/sec). Also, both rocks and rock-beds were preferred but artificial facilities were avoided. This ecological study of river otters using habitat use analysis and diet analysis by rumen contents will be useful fundamental information to conserve the river otter populations, and to protect their habitats.

• Korean Journal of Heritage: History & Science
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• v.44 no.2
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• pp.46-57
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• 2011

The aim of this study was to examine the current situation of otter inhabitation and conservation and to collect basic information for establishing appropriate policies. We conducted the study around the Bukhan river from April to October 2009, mostly focusing on otter distribution, feeding habits, threats, and conservation measures. We divided the study area into 2 sectors: the dam area and the stream. We found 39 spraint sites in the dam area and 70 in the stream area. A significant difference was observed in the number of spraint sites between the upper stream and the lower stream. To evaluate the feeding habit, we collected and analyzed the frequency and bulk occurrence of the spraints. Among the prey items, fish were the most numerous (36.99%) followed by amphibians (17.22%). Fish showed the highest bulk occurrence in the dam area, and the bulk occurrence of amphibians and insects seemed to increase in the stream area. However, the bulk occurrence in the dam area seemed to be lower than that in the stream area (ANOVA, F = 3.99, p < 0.05). Fyke nets and abandoned fishing nets were found to be the most threatening factors. Further research on the systematic management of otters and the use of stop grids is required for better conservation of otters.

• 한국공간정보시스템학회:학술대회논문집
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• 2005.05a
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• pp.175-179
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• 2005

본 연구는 2002년 10월부터 2003년 9월까지 경상북도 봉화군 운곡천을 대상으로 수달의 배설물 및 배설지 등의 흔적조사를 통해 얻은 GPS좌표를 중심으로 하여 수치지도 및 현장조사에서 얻은 정보를 Arc/view를 이용해 수달의 최적 서식지분석에 이용하였다. 분석결과 수달의 서식지 이용에는 먹이자원인 어류의 종다양도와 풍부도가 깊은 연관을 맺고 있으며 식생 등의 서식환경이 밀접한 연관을 맺고 있음을 확인하였다 또한, 밀집된 주거지 등 인간의 간섭은 수달의 서식지 이용에 교란요인으로 작용한다는 것을 알 수 있었다. 본 연구는 수달의 보전 및 관리를 위한 적합 서식지를 선정하기 위해 GIS기법의 활용에 대한 적용 가능성을 평가하였다.

• Korean Journal of Environmental Biology
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• v.24 no.1 s.61
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• pp.89-94
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• 2006

This study was conducted to infer habitat distribution of Eurasian otter Lutra lutra in Korea. We recognized trace or presence of otter spraints from 254 of 750 pixels (pixel size: 13.75X11 km) used in this survey, amounting to 34%. The highest frequency of localities, with the spraints present, occurred in Gyeongsangbuk-do (49.62%) and the lowest one was observed in Gyeonggi-do (7.36%). The other regions were as follows: Gangwong-do (49.56%), Chungcheong buk-do (41.67%), Gyeongsangnam-do (38.00%), Jeolabuk-do (37.93%), Jeolanam-do (24.24%), Chungchengnam-do (20.29%). The counted number of the spraints was very low level in most of the localities where they were found (1.7spraints per sprainting site). It may indicate that small size of local populations would be expected in most of the localities. The habitat distribution of Korean otter, inferred from the distribution pattern of the spraints, will provide valuable basic information required for conserving and managing Korean otter.

• Korean Journal of Ecology and Environment
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• v.47 no.spc
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• pp.66-73
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• 2014

In order to determine whether vegetation would be one of the factors for the selection of otter home range, vegetation structure and other potential factors were studied in Hwacheon, Korea. Thirteen sites, otter's activity found and not found, were investigated in North Han River and connected tributary streams of Hwacheon-gun. Three types of vegetation were classified by cluster analysis, which is short grass, tall grass and shrub type. Vegetation zone of each channel is composed of either one type, or mosaic of tall grass and shrub type. Short grass type is common in Lake Paro and upper North Han-river where water level is highly variable throughout a year. Therefore, annual species such as Persicaria nodosa, Fimbristylis dichotomam and Chenopodium ficifolium are the most dominant. Shrub type is common at the downstream sites of Jichon stream and along mainstream of North Han River down Lake Paro. A shrub species, Salix koreensis, is the most common. Tall grass type is dominant occupying the most vegetation zone of the tributary channels. Phragmites japonica is absolutely dominant. Due to its dense cover, a few plant species are co-existed. Otter activity was found in all three vegetation types and no marked activity was found at some sites of tall grass type. There is no difference in species composition and physiognomy between tall grass sites with and without otter activity, while it shows significant difference in fish availability between two groups. Overall we found that home range of otters in the region is along the mainstream and downstream of tributary streams with high fish availability in all vegetation types and in various human activity levels.

• Journal of Wetlands Research
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• v.17 no.4
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• pp.402-406
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• 2015

This study aims at favorable environmental conditions by river otter residing in Hongcheon river ecosystems using spraints along the river. Otter spraints were indicative of habitat use pattern and marking a territory in the areas. Nae-chon and Kuneob-chon river otter spraints were collected totaling 478 with 8 times during 2009-2011, and based on the number river use patterns were analyzed with the technique of index of dispersion. Results with larger than one indicated that river otter habitat use pattern were not random; instead they used preferred areas for habitat use. 'I' values greater than one indicate a clumped distribution and lower than one indicate random distribution. This study also demonstrated that we need a sophiscated linear model that should be developed to identify key habitat elements in river ecosystems.

• Journal of Wetlands Research
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• v.14 no.4
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• pp.591-596
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• 2012

Stream of Hongchon in Gangwon province was well known site for river otter(Lutra lutra) habitat. Because of habitat importance in this region a food analysis was conducted using 478 spraints of the species. A total food was domintnant by fish species occupying 80.5% and the dominant species was Zacco temminckii because of population abundance. Other food items were Amphibians and birds. Summer food was the highest due to its diversity. Gunup and Naechon streams were not different among diversity. Currently the highway construction was underway and we need more information regarding habitat requirement, and management implication for the species in this region.

• Journal of Life Science
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• v.22 no.6
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• pp.736-743
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• 2012

The aim of the study is to investigate the food habits of the Eurasian otter, Lutra lutra, and to examine any effects of the construction of the Busan New Port (BNP) on the prey. The frequencies and bulk estimate ratios of the biological debris, taken from spraints collected seasonally during the period from 2005 to 2011 at 16 areas, were analyzed. As the results, it was demonstrated that otters prey mainly on fish but occasionally on crustaceans and gastropods, etc., and the Mugiliformes was the most preferred fish. Although fish debris was observed throughout the season, it was suggested that the amount of fish eaten by the otter seemed to be associated with the amount of fish inhabiting the study area, judging from the striking similarities in the pattern of seasonal variations in each order of the fish between the frequency from the spraints and the fish catch. On the other hand, the frequencies of most of the fish, crustaceans, and gastropods from the spraints decreased from 2010, indicating the decrease of the amount of the prey by the construction of BNP and the strong possibility of the decrease in the number of otters in the near future. This is supported by the other studies, such as one showing a sudden decrease in the number of spraints since 2010, recent decrease in the fish catch, and the increase of marine pollution at this study area.

• Korean Journal of Environment and Ecology
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• v.37 no.2
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• pp.140-150
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• 2023

The Eurasian otter (Lutra lutra) is an apex predator of the riparian ecosystem. It is a keystone and an indicator species; consequently, its presence suggests a sustainable water environment. Otter is a keystone species as a predator at the top of the food web in the aquatic environment and an indicator species representing the health of the aquatic environment. Although Eurasian otters disappeared from the Han River urban water system because of anthropogenic activities like habitat destruction, poaching, and environmental pollution in the 1980s, the species were sighted in the Cheonggye Stream, Jungrang Stream, and Seongnae Stream, which are urban sections of the Han River, in 2016 and 2021. Therefore, it is pertinent to assess the habitat potential in the area for conservation and management measures to ensure its permanent presence. However, existing studies on otter habitats focused on natural rivers and reservoirs, and there is a limit to applying them to habitats artificially confined habitats in narrow spaces such as tributaries in urban areas of the Han River. This study selected the Cheonggye Stream, an artificially restored urban stream, to evaluate its potential as a habitat for Eurasian otters in urban water environments using the habitat suitability index (HSI). The HSI was calculated with selected environment attributes, such as the cover, food, and threat, that best describe the L. lutra habitat. According to the results, the confluence area of Seongbuk Stream and Cheonggye Stream and the confluence area of Cheonggye Stream and Jungnang Stream were suitable otter habitats, requiring appropriate conservation efforts. The HSI model suggests a valuable method to assess the habitat quality of Eurasian otters in urban water environments. The study is crucial as it can help rehabilitate the species' populations by identifying and managing potential Eurasian otter habitats in highly urbanized areas of the Han River basin and its tributaries.

• Spatial Information Research
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• v.12 no.1
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• pp.29-42
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• 2004

This Study was Analysis about Habitat of Eurasian otter Lutra lutra L. In October 2002 during September 2003, Otter Spraints and Sprainting site were searched in river Unkog of North-Kyongsang Province for taking the GPS coordinates. For Analysis of habitat, This data were used by Arcview ver. 3.2 with 1/25000 Topology Map and Other Field data. The result of Habitat Analysis meant that Habitat use was strongly related to Fish diversity and richness also vegetation and cover were connected with otter habitat. In other hand, The Human interferences including dense structures like House acted as factor of disturbance. This study suggest that The preceding about Suitable habitat having free of Human disturbance, abundant fish and good vegetation is essential In Trial for Conservation or Recovery of Otter like Trans-location.