• Journal of Ecology and Environment
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• v.36 no.4
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• pp.217-222
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• 2013

Sea temperature in the South Sea of Korea has been increased over the last decades. Seabirds are sensitive to changes in food availability in marine environment. In this study, we investigate the diet of Black-tailed gulls (Larus crassirostris) during the breeding season to identify changes of marine environment and biological response such as breeding performance in the South Sea of Korea. A total of 22 fish species or family (n = 128) from regurgitates by chicks were collected on Hongdo Island in 2002 and 2012. The most important prey item was Japanese anchovies (Engraulis japonicas). Proportion of Anchovy in diet increased in 2012 (70.5%) compared to 10 years ago (27.5%). Some species were newly found in 2012: Spotted chub mackerel (Scomber australasicus), Pacific sand lace (Ammodytes personatus), White ventral goby (Acanthogobius lactipes), Silver-strip round herring, Multicolorfin rainbowfish (Halichoeres poecilopterus), Silverside (Hypoatherina tsurugae), Surfperch (Neoditrema ransonneti) and Spotnape ponyfish (Leiognathus muchalis), but not in 2002. Especially, sub-tropic fish such as Kammal thryssa (Thryssa kammalensis), and Rosefish (Helicolenus hilgendorfi) were frequently observed in the diet of 2012. These results might reflect the increase of sea temperature in the South Sea of Korea.

• Korean Journal of Ichthyology
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• v.13 no.4
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• pp.223-229
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• 2001

Feeding habits of juvenile Sillago maculata, collected from the tropical seagrass beds in Cockle Bay, Queensland, were studied. S. maculata (0.5~9.5 cm SL) was a carnivore which consumed mainly gammarid amphipods, crabs and copepods. Its diets included small quantities of polychaetes, shrimps, fishes, isopods and cumacean. S. maculata showed ontogenetic changes in feeding habits. Small individuals preyed mainly on copepods, crab larvae and gammarid amphipods. While the portion of the stomach contents attributable to polychaetes, crabs and fishes increased with increasing fish size, consumption of copepods and crab larvae decreased progressively. Gammarid amphipods were the most selected prey item for all size classes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.26-30
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• 1998

Stomach contents of the common squid, Todarodes paciかcus in the Korean waters were analyzed using the samples taken from February, 1991 to July, 1992. Stomach contents of T. pacificus consisted of pisces, cephalopods, crustaceans, algae and unidentified things. Pisces were the most selected prey items. Major food items of summer and autumn populations were pisces, but that of the winter population was cephalopods. Algae and crustaceans were minor food items of the squid, T. pacificus mainly fed on pisces and three populations of the squid did not have different stomach contents.

• The Korean Journal of Ecology
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• v.8 no.2
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• pp.119-126
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• 1985

One nest of the Common Kingfisher Alcedo atthis bengalensis Gmelin breeding in the area of Mt. Bangu, Mugye-ri, Jangye-ri, Jangyu-myon, Gimhae-gun, Gyongnam province, was observed for 43 days from July 18 to August 29, 1984. The nest was found at a height of 71cm in a steep mountain side. It was tunnel-shaped, with a size of 53cm(length), 5.5*6.4cm (the diameter of entrance) and 16.1*10.5cm (the diameter of incubation seat). The cluth size was 5 eggs. The eggs were white in color, the average size of 5 eggs being 20mm (length)*17.9mm(width). The incubation period was 18 days, the parent birds stayed in the nest at on average of 494 minutes and the rate of incubation was 82.20%. The incubation time increased gradually. The nesting period of 3 chicks was 25 days, and the average feeding frequency was 5, 50 times per day with the highest frequency of 10 times on the 14th days after hatching. The time and frequency of attendance gradually decreased as their chicks grew up. Total increase length in body was; body length 45.35longrightarrow147.80mm, wing 6.95longrightarrow63.40mm, bill 1.73longrightarrow29.36mm and body weight 2.93longrightarrow41.00gr. The prey for the 3 chicks of the nest was entirely fish. The main food item was the fry of Gobiobotidae. The home range of the nest was 0.43ha. and the territory size was 0.05ha. Their feeding ground were outside of their territory.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.4
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• pp.637-643
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• 2015

The diet composition of juvenile Trachurus japonicus were studied using 195 specimens collected from 2013 (May, June, July, and September) to 2014 (May, June, and July) in the coastal waters of Geumodo, Yeosu, Korea. The size of juvenile T. japonicus ranged from 4.3 to 15.2 cm in body length (BL). Juvenile T. japonicus was carnivorous and crustaceans predators that consumes mainly consumed copepods. Its diet also included small quantities of decapods, cirripedians, nematods, chaetognathans, fishes, amphipods, cumaceans, ostracods and euphausiids. The graphical method for feeding strategy revealed that juvenile T. japonicus is an opportunistic and specialized predator on copepods, especially Corycaeus. affinis, and showed narrow niche width. Juvenile T. japonicus showed ontogenetic diet change. Small size group individuals (4.3-8.0 cm BL) mainly consumed copepods. The portion of this prey item decreased in the large size group (8.0-15.2 cm BL), and this decrease was paralleled with increased consumption of decapods.

• Journal of Environmental Impact Assessment
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• v.24 no.5
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• pp.532-548
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• 2015

The winter ecology of individual yellow-throated martens(Martes flavigula) intemperate region of Korea were studied through snow-tracking. The study was performed across 3 winter seasons, from January 2011 to February 2013. Total distance of 49.8km was snow tracked (comprising 13 snow-tracking routes) to determine winter foraging habits, general behavior and movement paths of solitary and small groups (1-6 individuals; $mean=2.9{\pm}1.6$) of yellow-throated martens. The martens in the current study were omnivorous, with their winter diet including 9 animal and 5 plant species. Yellow-throated martens searched for food near and under the fallen logs and branches, root plates of fallen trees, around the roots of growing trees, and in small holes in the ground. They also climbed trees to search inside the tree holes and vacant bird nests. Foraging activity was estimated to occur at a frequency of 1.20 times/km, while territory marking occurred 1.42 times/km on average. Of the 60 documented foraging activities we observed, 17 were successful (28.3%). Moving activity and territory marking mainly occurred along ridges, whereas foraging activity was recorded in valleys, slopes, and forest edges. To protect the habitat of this species, the entire forest should be preserved, including the valleys, slopes, and even forest edges as well as main ridges.