• Journal of Ecology and Environment
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• v.44 no.1
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• pp.54-61
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• 2020

Background: Most fish undergo prey switch from juvenile to adult. It is thought that slightly different feeding habits occur among adult fishes due to growth, spawning, habitat change, and so on. Therefore, the diet of the John Dory Zeus faber (≥ 24 cm TL) was studied in the coastal waters of Korea by analysis of stomach contents, with comparison by season and size class of diet composition and prey diversity. Monthly samples were taken from February 2017 to January 2018. Results: The results showed that the John Dory was a piscivorous predator, and pisces had occupied 82.3% of IRI%. Trichiurus lepturus and Trachurus japonicus were important preys in all size classes and seasons. Diet composition differed among the size classes and seasons (Chi-square test, P < 0.05). As body size of Z. faber increased, the occurrence of benthic fish (Glyptocephalus stelleri) tended to increase. The seasonal prey composition also changed depending on the abundant species of each season. Conclusions: Z. faber is a piscivorous predator. The consumption habits of Z. faber appear to different results by their size and seasons. This study suggests that Z. faber could be considered an opportunistic predator.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.694-700
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• 2016

Specimens of Callionymus beniteguri (n=89) were collected from the waters off the coast of Taean, Korea, between April 2008 and January 2009, and their feeding behavior was observed. C. beniteguri (4.0-15.5 cm SL) was found to be a bottom-feeding carnivore that primarily preyed on gammarid amphipods, and secondarily consumed polychaetes but also ingested bivalves, shrimps, cumaceans, and sea urchins. Six additional minor prey groups also contributed to its diet, but the index of relative importance (IRI) for these groups was relatively low (<1.0). C. beniteguri exhibited size-related dietary changes. Small individuals (<10 cm SL) mainly consumed amphipods. As fish size increased, amphipods tended to decline in IRI, while the contributions of bivalves, sea urchins, and polychaetes became more important.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2008.04a
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• pp.34-37
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• 2008

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.516-522
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• 2014

This study was conducted to investigate the impact of the anthropogenic factors affecting distribution of the Red-crowned Crane and White-naped Crane wintering in Cheorwon, Korea. Especially, it was investigated that the impact power and its range of the anthropogenic effect to the feeding flock density in cranes due to the paved road, residential area, military facilities and greenhouse density. The Red-crowned Crane and the White-naped Crane showed the similar preference and sensitivity against anthropogenic factors, because correlation of feeding flock density of the Red-crowned Crane and White-naped Crane was similar in the same site. The feeding flock density of the cranes near the residential area was lower than that of area far from the area, and tended to increase within 2.5 km distance. The increasing tendencies of feeding flock density from military facilities and high traffic volume road were similar, but the density in military facilities increased within 0.8 km, and the density from high traffic volume road increased within 2 km. This results suggested that military facilities and the road with high traffic volume made significant influence on foraging densities to the certain range. As the distance from the road with low traffic volume increased, feeding flock density tended to decrease. The area near the low traffic volume road had high feeding flock density because remaining rice grains were preserved by intermittent disturbances in that area. If the density of greenhouse is lower than $40/km^2$, feeding flock density in the low greenhouses density area was higher than high greenhouses density area. However, there was no difference in the feeding flock density if the density of the green houses is higher than $40/km^2$.

• Journal of Ecology and Environment
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• v.41 no.1
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• pp.29-33
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• 2017

This study was conducted to clarify the size of the home range and movement distance of juvenile black-faced spoonbills from post-fledging until fall migration using a Global Positioning System (GPS)-wideband code division multiple access (WCDMA)-based telemetry system along the west coast of South Korea. The home range of juvenile black-faced spoonbills (n = 3) was $45.2km^2$ in size and the core area consisted of $8.4km^2$ within the Baeksu mudflat, Yeonggwang, South Jeolla Province, South Korea. Mean weekly movement distances were not significantly different (Kruskal-Wallis test, Z = 3.47, P = 0.18) among individuals, ranging from 0.1 to 23.9 km during the study period. The home range and movement of juvenile black-faced spoonbills were related to intertidal areas, especially to their use as feeding areas.

• Journal of Ecology and Environment
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• v.31 no.2
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• pp.147-151
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• 2008

Feeding methods of five species of herons and egrets were studied in an agricultural landscape in Asan city, Chungcheongnam-do, Korea in 2006. Grey herons primarily hunted while standing, whereas great egrets fed while walking slowly. Two smaller species, little and cattle egrets, were active foragers, feeding both while walking quickly and walking slowly. Little egrets were the only species using the foot stirring method. The medium-sized heron, intermediate egrets, foraged mainly while walking slowly or leaning. For grey herons, great egrets and little egrets, the frequency of use of different feeding methods was different between habitats: these species used the leaning method more frequently in rice fields than in reservoirs and ditches. Also, most herons (all species other than great egrets) showed seasonal changes in their feeding methods that are related to changes in habitat condition.

• Journal of Ecology and Environment
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• v.31 no.4
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• pp.341-344
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• 2008

We investigated the responses of red squirrels to pine nuts (Pinus koraiensis) treated with Lithium Chloride (LiCl) and the potential of the chemical for inducing conditioned taste aversion (CTA) in red squirrels. In red squirrels, nut feeding declined dramatically during the first 4 days after feeding with LiCl-treated nuts. The ratio of LiCl-treated nuts eaten to total nuts eaten declined from the $1^{st}$ day in LC-1 and the $2^{nd}$ day in LC-2, along with a general reduction in quantity eaten. Thus, feeding with LiCl-treated nuts induced CTA from the 2nd day after feeding, and CTA remained constant until the $4^{th}$ day, but disappeared on the $5^{th}$ day. The squirrels ate an average of $757.0{\pm}106.1mg$ (n = 2, range $682.0\sim832.0$) of LiCl before dying on the $16^{th}$ day of the study. The lethal dose of LiCl was 2.32 mg LiCl/g body weight, and the average amount of LiCl needed to induce CTA was $23.0{\pm}4.24mg$ (20 mg in LC-1 and 26 mg in LC-2).

• Korean Journal of Ichthyology
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• v.23 no.4
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• pp.278-287
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• 2011

Habitat environment, age and feeding ecology of Gobiobotia macrocephala were investigated to provide baseline data for ecological characteristics and recovery in the Seom River at Heungho- ri, Buron-myeon, Wonju-si, Gangwon-do, Korea from 2010 to 2011. G. macrocephala inhabited 10~40 cm in water depth, 8~20 cm bottom size and 40~120 cm/sec in current velocity, and pebble floor were factors to be important for inhabit density. Age group of G. macrocephala in May estimated from the standard length indicated that the 28~42 mm group is 1 year old, the 43~58 mm group is 2 years old, the 59~69 mm group is 3 years old and the 69~85 mm group is more than 4 years old, and the female was 4~10 mm larger than the male. G. macrocephala did mainly feeding with nocturnal fishes between 00 h to 06 h, and they fed mainly Trichoptera (57.7%), Diptera (26.0%) and Ephemeroptera (16.3%). And their small juvenile fed mainly Ephemeroptera and Diptera, however, they ate mainly Trichoptera while growing to adult fish.

• Korean Journal of Ichthyology
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• v.26 no.4
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• pp.303-309
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• 2014

Feeding ecology of Collichthys lucidus was determined by analysis of stomach contents of 926 specimens ranged from 3.5 to 18.5 cm in the Han River estuary. This fish actively fed on benthic crustaceans, mainly decapods, Palaemon carinicauda and Acetes chinensis, and they can be defined as the benthivorous predator. The percentage of empty stomachs was 23.8%. The vacuity index (VI) did not vary with the size classes, but showed significant monthly variations. Monthly variation of feeding activity appears to be related to the reproduction cycle of the fish, and to the temporal abundance of the prey organisms. Collichthys lucidus in Han River estuary fed on a wide array of prey items and could be considered as a non-selective predator.

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.46-46
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• 2003

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