• Korean Journal of Environment and Ecology
• /
• v.16 no.1
• /
• pp.34-45
• /
• 2002

Of the four tidal flat areas(Yeocha-ri, Dongmak-ri, Sundu-ri and Donggum-ri) on Southern Ganghwa Island, the distribution of migratory waterbirds showed a difference in the numbers of individuals and species. Higher numbers of individuals and species were observed on the Yeocha-ri tidal flat. The dominant waterbirds species at the four areas was the Dentin(Calidris alpina). This species showed an occupancy rate(42.0-79.1%) on the Yeocha-ri tidal flat, which was much higher relative to the other areas. The Yeocha-ri tidal flats were higher relative to MSL than the other tidal flats. When the Dongmak-ri tidal flat was covered by sea water, the Yeocha-ri tidal flat was 0.0317$\textrm{km}^2$ in area and on this space we observed many resting waterbirds. The biomass of the waterbirds' potential prey on the Yeocha-ri tidal flat was higher(1.6~2.5$\times$) than other tidal flats. Twenty-three species and 266 individuals were found on the Yeocha-ri tidal flat, which was higher than the tidal flats. The food of Dunlin, which was the dominant species in these four areas, was mainly Reticunassa festiva and Umbonium thomasi(Gastropoda) and Perinereis aibuitensis(Polychaeta). A Dunlin(38.11g) used to eat 1,295 individuals of these food items for daily basal energy. Gastropod, its density was highest on Yeocha-ri tidal flats. The distribution of waterbirds seemed to be closely related with the distribution of the benthos, space and safety of resting site. We suggest that the environments of tidal flats, which are rich foraging habitats, are important factors for conservation of waterbirds.

• Korean Journal of Environment and Ecology
• /
• v.19 no.4
• /
• pp.385-392
• /
• 2005

This study was conducted in order to analysis the forest fire effect to the raptors habitating in and around the large forest fire occurred area, Goseong country, Gangwon province, Korea. There were observed raptor birds belonging to 8 species, 3 families, and 2 orders in the survey area. The most dominant species was Eurasian Hobby(Falco subbuteo), which was followed by Common Buzzard(Buteo buteo), Kestrel(Faico tinnunculus) and Chinese Sparrow Hawk(Accipiter soloensis). The largest number of species and individuals were observed in May 2002. In partially undamaged areas and undamaged areas, five species of rapacious birds were observed, which was the largest number of species observed. If an environment where rapacious birds can build nests is created in forest fire damaged area in order to raise the number of species and population, the number of species and population of rapacious birds living in the forest fire damaged area will grow further.

• Korean Journal of Environment and Ecology
• /
• v.24 no.3
• /
• pp.227-234
• /
• 2010

To see the influence of bird species by the change of temperature in city, we have carried out bird census 22 times for 6 years from 2003 to 2008 in Worldcup Park, Seoul. And we analysed the correlation between the temperature of Seoul and wildbirds. 15 orders, 38 families and 102 species were confirmed to have existed. We could find that Hypsipetes amaurotis gradually turned out to have increased with statistical significance for 6 years. To analyze the relationship between the temperature of Seoul and wildbirds, we have chosen 31 bird species observed more than 30% in frequency and proceeded the regression analysis. The survey shows that with the temperature rise the number of the resident birds such as Pica pica, Parus palustris, Anas platyrhynchos and Anas poecilorhyncha and the migratory birds such as Buteo buteo has declined. These 5 species have a possibility to be decreased as a global climate warming and maybe move to another habitat. In contrast, Oriolus chinensis and Falco tinnunculus are characterized into the species that increased due to the rising temperature. So they have a posibility to increase and expand their habitat. This survey shows that temperature rise can cause to change the composition of bird species. And 7 bird species related with the change of temperature have a great possibility as a indicator of the climate change.

• Journal of Environmental Impact Assessment
• /
• v.21 no.6
• /
• pp.879-891
• /
• 2012

The objective of this study was to evaluate seasonal patterns and diel variations of fish movements in the Juksan Weir which was constructed in 2010 at the down-stream of Yeongsan-River watershed. For this study, we monitored day-and-night movement(24 Hr cycle) and seasonal fish migration(June ~ August) patterns in 2011 along with species compositions and abundances depending on the locations of the traps within the fishway. Total number of species sampled was 14 and the total number of individuals was 1,263 with only the size-fractions(as total length) of the fish < 20 cm during the study. Seasonal analysis of fish movement in the fish way showed that highest frequency in the movement occurred in June - July, which is closely associated with a spawning peak season. The most dominant species using the fishway was Squalidus chankaensis tsuchigae, and this species turned out to be 26.9% of the total in the use rate of fishway. Daily monitoring of fish movements showed that most frequent movements occurred between 18:00 PM and 21:00 PM when the fish have a feeding time generally. The migratory fish were not found in the fishway during the study. Mean current velocity during the study $0.42{\pm}0.02ms^{-1}$(n = 42), and there were no significant statistical differences(p > 0.05) among the daily and monthly velocities in the fishway. The use rate of fish passage, in terms of fish species, was 48%, compared with total sampling of fish species(29 species) at the down-river regions during the same period, indicating a low use rate. Further continuous long-term monitoring should be conducted to evaluate the impacts of the weir construction in the river.

• Korean Journal of Environmental Biology
• /
• v.33 no.1
• /
• pp.34-44
• /
• 2015

Fish fauna, difference of stable isotope ratio between freshwater and seawater, and trophic guilds of freshwater fishes were investigated in the lower Geum River. The study was conducted in 2011, and total study area was about 30 km of 20 km upstream and 10 km downstream from the Geum River estuary barrage. Only freshwater fishes were used for analyzing trophic guilds, and discriminant function analysis (DFA) was utilized to reclassify trophic guilds based on stable isotope ratio. Fish fauna in freshwater and seawater areas were entirely different each other, but small number of migratory species such as Coilia nasus and Chelon haematocheilus occurred both areas. Other species were not collected in the different areas because they did not have physiological ability to adapt different salinity concentrations. Stable isotope ration of two areas were different considerably due to food sources. Estuary and seawater fishes uptake food sources originated from marine, and freshwater fishes were from freshwater and terrestrial. Some migratory species showed reverse stable isotope ratio. Even though they collected in freshwater, they showed stable isotope ratio of seawater. This is because ecological characteristics of each species. Trophic guilds of freshwater fishes were reclassified by DFA, and showed slight difference with literatures. However, because this result is related with ontogenetic shift of species, more studies are needed to explain exact and correct trophic guilds. Stable isotope ratio can be changed among regions, seasons and ontogenetic stage, thus we always consider these aspects when analyzing results to get a right answer.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.31 no.2
• /
• pp.160-167
• /
• 1998

Proximate composition, cholesterol (CHOL) and $\alpha-tocopherol$ ($\alpha-Toc$) content of seventy-two species of fish muscle (sea water fish, 59 species; fresh water fish, 13 species), which caught off Tongyeong coast of the Southern Sea ( Nam-Hae) and caught Kyeongho river, Sancheong, Korea, were determined. Lipid content was ranked from $0.53\%$ to $20.4\%$ and was high in the following order; mid-surface dwelling and migratory fish ($6.09{\pm}4.25\%$) > fresh water fish ($4.40{\pm}5.90\%$) > coastal and reep dwelling fish ($3.41{\pm}2.68\%$) > demersal fish ($2.12{\pm}2.41\%$). There was a negative correlation between the lipid and moisture content in all fish groups (p< 0.001). Protein was approximately $17\~18\%$ in all fish group, and no correlation was between the protein and moisture content in all but the demersal fish, which there was a negative correlation between both contents. Ash content was almost constant in all fish, accounting for $1\~2\%$, Cholesterol (CHOL) content was shown a great difference according to the fish species from 6.7 mg/100 g muscle (grass fish) to 249 mg/100 g (eel) and there was a positive correlation between the lipid and CHOL content. $\alpha-Toc$ content was less than 3 mg/100 g muscle in all fish, except that of eel (4.1 mg/100 g) and was relatively rich in the fish species contained a large amount of lipid.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.17 no.1
• /
• pp.68-80
• /
• 1984

Garolim Bay is not only important fishing ground but also expected area for the tidal power plant. The construction and operation of tidal power plant will make change the ecosystem of this bay. Therefore, the actual fisheries stocks should be precisely understood for the effect estimation and overall utilization of the bay after the construction of the tidal power plant. During the study period from January through December in 1981, forty-six adult fishes species, 3 species of fish egg and 25 fishes larvae species have occurred in the bay. Considering the result on monthly distribution of eggs and larvae, the inner area of the bay seems to be important as nursing ground of larvae spawned at the outside bay in winter, e. g., Ammodytes personatus, and Enedrias sp. This inner bay is also major spawning ground for many species spawning in spring and summer, e. g., Gobiidae, Konosirus punctatus, Engraulis japonica, etc. Taking into consideration the annual mean production for three years($1978{\sim}1980$), there are two major fishing seasons. The one is in May-June for Enedrias larvae stock, and the another in October-November for big eyed herring stock. For the mariculture stocks, short necked clam, oyster and laver are important species. After construction of the tidal power plant, the migratory species, i. e., larvae of Enedrias and Ammodytes personatus, Mugil cephalus, Konosirus punctatus, etc. will be directly damaged by the interuption of migration route. On the otter hand, the change of physico-chemical factors of seawater will also affect the ecosystem of the bay. Consequently, for the overall utilization of the bay after construction, the actual ecosystem including the fisheries stocks, must bs precisely revealed, and the mechanical designs, e. g., sluice position and its demension, should be also considered with these biological characters of the bay.

• Korean Journal of Ecology and Environment
• /
• v.53 no.3
• /
• pp.255-264
• /
• 2020

The use of fishway has been investigated up to 2~9 years, continuously each month and over the long term that installed in 6 domestic rivers. The fish's use of fishway has been investigated as direct collection by trap in exit section of the fishway. The population structure of fish using 6 fishway and the fish that live in the river showed difference. About 2 to 7 species of fish took possession of more than 80% of total use of fish in fishways. This seems to be not the results of attraction flow in fishway but specialized result of physiology characteristic followed by species of fish. In addition, the distribution of fish species using fishway was different with the fishways installed in river. This difference seems to be consequence of the place that of the river and fishway types. Generally, the fish species were less and had high ratio of home migratory fish in vertical slot type fishway, which shows relatively fast velocity of water flow. This analysis result of major fish species using fishway can be used in planning fishway and to choose major targeted species for the planning.

• Korean Journal of Environmental Biology
• /
• v.29 no.3
• /
• pp.113-125
• /
• 2011

Seabirds have adapted to life in marine environments. More than 25% of the bird species observed in South Korea are seabirds, using the coast area of Korean peninsula as a stop-over and wintering, and breeding site. The aims of this review are to provide information about migratory and resident Korean seabirds and to discuss the methods that are currently employed to monitor the marine environment. In Korea, it has been reported that more than 400,000 individuals of seabirds breed on Nando Islet, Chilbaldo Islet, Guguldo Islet, Sasudo Islet, Hongdo Islet and Dokdo Islet. In 2010, approximately 160,000 seabirds also visited South Korea during the winter. Two of the main treats were introduced wildlife and habitat destruction by humans. Seabirds are monitored mainly at the population and individual levels. The assessment of population sizes and biomagnifications of pollutants are performed preferably at the community and population levels. Behaviour, growth, morphological characteristics, and breeding success is analyzed at the individual level and employed to gauge the health of the marine environment. In addition, we could suggest that molecular technique of seabirds successfully adopted to investigate the effects of pollutants and toxins in the marine environment.

• The Journal of Fisheries Business Administration
• /
• v.48 no.3
• /
• pp.61-74
• /
• 2017

This study is aimed to analyze the change of chinese fishing vessels' entry into the East Sea off North Korea and suggest directions for countermeasures. Based on the real landing data in China, Chinese fishing vessels' squid catch volume and value in the East Sea off North Korea are estimated. Results show that at least 205 thousand tons of squid was caught by Chinese fishing vessels in 2014. If the catch amount is calculated by the unit price per kilogram at the same year in Korea, it would be 556.3 billion KRW. As the UN sanctions become stricter with the recent resolution 2371 passed, Chinese fishing vessels' entry may increase in the future to compensate decreased seafood supply from North Korea. Even though there are not many options left for Korea to decrease the impact of Chinese depletive fishing, the study suggests countermeasures such as strengthening cooperative crack down on the Chinese illegal fishing vessels in Korean waters; increasing cooperation with UN member countries to incorporate banning the trade of fishing rights in the next UN sanctions; establishing regional fisheries management organization and managing migratory species with China and Japan cooperatively in the long term.