• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.1
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• pp.115-123
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• 1996

For ecological study of Synechogobius hasta the environmental factors, length composition, stages of ovarian maturation, growth, and stomach contents of this species were examined. The samples were collected from the Kum River estuary from May, 1994 to June, 1995. The ovarian egg development of this species underwent 4 stages : the oogonium stage in October to November, growth stage in December to February of next year, maturity stage in February to April, and spawning stage in late April to middle May. The peak spawning period appeared in early to middle May. The fecundity varied from 8,600 to 49,000 showing a exponential increase by body size. The minimum size having matured eggs was 225 mm in total length (standard length 180 mm). The larvae smaller than 10 mm appeared in late May, and young fish of total length $13\~15mm$ entered into bottom life in the shallow waters. The young fish grew rapidly and reached about 141.7 mm in late October. The fish inhabited in the subtidal zone from December to May of next year when began to spawn. The largest specimen examined in this study was 531 mm of male, 472 mm of female. The major food items of young fishes were copepods and invertebrate larvae, and those of adult fishes were crabs, fish, shrimps, cephalopods, and polychaetes.

• Parasites, Hosts and Diseases
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• v.27 no.3
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• pp.197-202
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• 1989

This study was performed to observe the susceptibility of dogs and cats as definitive hosts of Paragonimus ilektsuenensis. The metacercariae of this luke were obtained from Sesarma dehaani collected at a focus near the mouth of Sumjin river in November, 1986 and February, 1987. The larvae isolated from the crabs were introduced Per os into 7 albino rats, 2 dogs and 3 cats. The adults were recovered from the experimental animals, End they were morphologically observed and measured. The results were as follows: 1. The recovery rate of adult worms at 42 days after infection was 53.3% from three albino rats, 21.0% from a dog and 12.7% from two cats. Most of the worms were recovered from the worm capsules in the lungs. 2. The size of worms recovered from albino rats, a dog, and cats 42 days after infection aver-aged $6.3{\times}3.2mm,{\;}6.3{\times}3.0mm,{\;}or{\;}6.2{\times}3.5mm$, respectively. There were little differences in the morphology of worms by different experimental animals. 3. The size of eggs from a dog was $88.9{\times}49.3{\mu\textrm{m}}$, and that from cats was $84.3{\times}53.7{\mu\textrm{m}}$ on average. Dogs and cats were good definitive hosts of p. iloktsuenensis. This fact suggests that human infection by this luke may be possible if the metacercariae were ingested.

• Korean Journal of Ichthyology
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• v.9 no.1
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• pp.71-78
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• 1997

Stomach contents of snailfish, Liparis tanakai, caught in the Nakdong River Estuary were examined quantitatively. Liparis tanakai was a bottom feeding carnivores, and showed an almost strict specialization on shrimps and fishes. Shrimps and fishes accounted for 74.3% and 19.8% of the overall stomach contents, respectively. The most selected prey species was Cragon affinis for all fish size classes. The snailfish' s diets included minor quantities of crabs, amphipods, mysids and isopods. Small individuals(4~10 cm SL) consumed mainly shrimps which accounted for approximately 90% of the stomach contents. However, the portion of the diet attributable to shrimps decreased steadily with increasing fish size, and this decrease was paralleled by increased cosumption of fishes. For 31~45 cm individuals, fishes constituted over 30% of the stomach contents, while shrimps made up approximately 60% of the diet.