• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.6
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• pp.982-987
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• 2015

During the study period, a total of 158 individuals of Synechogobius hasta were collected. The range of body length (BL) was 15.4-44.5 cm. The stomachs of 26.6% of the individuals were empty. The most abundant prey was shrimp. Among shrimp, Exopalaemon orientis was the most abundant species, being present in 27% in %IRI (index of relative importance). Fishes and crabs were also abundant prey. Analysis of ontogenetic changes, suggested that shrimp were the main prey of S. hasta of two size classes (<20 and 20-25 cm). The proportion of shrimp decreased, but that of fishes and crabs increased, with increasing body length, beginning at the 25-30 cm size class. In spring, fishes were the dominant prey, while shrimps, and crabs and fishes dominated in autumn and winter, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.2
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• pp.117-119
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• 1970

A goby Synechogobius hasta (TEMMINCK et SCHLEGEL) was studied on the length-weight relation-ship, and the fish were sampled from the closed tributary and the lower part of the Naktong River, near Pusan, during the period from November of 1967 to December of 1968. The data for this study were taken from 1,050 fish. The relationships between the body length (X) and body weight (Y) are indicated as follows: 7.5cm to 32.5cm: $Y=0.09863X^{2.17926}$ 7.5cm to 19.5cm: $Y=0.04995X^{2.472l6}$ 28.5Cm to 32.5Cm: $Y=0.0004127X^{3.67265}$ The normal relative growth was not found in fish between 20.5cm and 27.5cm in body length, because of the maturity of gonads and spawning.

• The Korean Journal of Zoology
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• v.33 no.4
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• pp.402-410
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• 1990

The osteological characteristics of Mudhopper, P. cantonensis, was described and compared with its related species, Tridentiger obscurus, Synechogobius hasta and Odontogobius platycephala The skeletal structures of P. canionensis were distinctly different from those of other species in many respects: the form of the neurocranium, the pterygoid, the radial and the parhypural, the fused state between ribs and hypomerals. However, in respect of having five branchiostegals, two epurals and hypomerals, P. cantonensis were in common with T obscurus, S. hasia and O. platycephala.

• 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.

• The Korean Journal of Ecology
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• v.13 no.4
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• pp.267-283
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• 1990

The studies on the dynamics of fish communities in Manggyong River estuary were carried out from September 1989 to August 1990. The results, the fishes of 77 species belonging to 66 genera and 37 families were collected and identified. The dominant species in surveying areas were Thrissa koreana, Harengula zunasi, Synechogobius hasta and Konosirus. T. koreana was grown up to about 110mm of toatl length for a year, H. zunasi about 120mm, K. punctatus about 160mm and S. hasta about 220-460mm, respectively. The spowning season of S. hasta was from March to April, K. punctatus from April to June, H. zunasi from May to June and T. koreana from June to July, respectively. T. koreana and S. hasta belonged to to carnivorous, K. punctatus herbivorous and H. zunasi showed feeding habits of omnivorous fishes.

• Korean Journal of Ichthyology
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• v.4 no.2
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• pp.1-25
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• 1992

Taxonomic study of the five species (Acanthogobius elongata, A. flavimanus, A. lactipes, A. luridus and Synechogobius) from Korea was carried out based on morphometric, cephalic sensory canal and ecological characters. Taxonomic revision and classificational keys are provided. Synechogobius hasta is easily distinguished from four species of the genus Acanthogobius in eleven characters, i. e., the number of dorsal and anal fin rays, the transverse scales, the vertebral numbers, the formula of interneural spine of the first dorsal fin, the number of interhemal spine anterior to the first hemal spine, the number of epipleural and pleurals, the ratio of caudal peduncle length, the ratio of caudal peduncle depth and the regular variations in the ratio of body parts with the body length. In the genus Acanthobobius, A. elongata is distinguished from other 3 congeneric species in the ratio of body parts and the oculoscapular sensory canal. Moreover, A. flavimanus differs from other 3 congeneric species in the lateral scales, the transverse scales, the number of predorsal scales, the vertebral number, the number of epipleural and pleurals. Sensory papillae rows of S. hasta is not similar that of the genus Acanthogobius in having a singular sensroy papillae rows. A. elongata has no oculoscapular sensory canal D and A. flavimanus has transverse sensory papillae in cheek, and these are one of the unique characters distinguished form other congeneric species. In the spawning period inferred from gonadosomatic index, A. elongata varied from late March to late June ; A. flavimanus, January to April ; A. lactipes, May to September ; A. luridus, early May to early July and S. hasta, early March to early May.

• Korean Journal of Ichthyology
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• v.12 no.4
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• pp.259-263
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• 2000

The investigation of the fishes was conducted based on the specimens from the Wooi-Islands, southern west coast of Korea in August, 1998. The fishes were composed of 25 species and 22 genera belonging 15 families. Among them, the gobiid fishes composed of 6 species and the combtooth blennies of 3 species. The gobiid fishes, Chasmichthys dolichognathus, Tridentiger trigonocephalus and Synechogobius hasta were most commonly found in the intertidal area of these islands. One specimen collected from tidepool at tentatively identified as Abudefduf bengalensis of the family Pomacentridae for the first time from Korea. This species was characterized by having seven black bars on the trunk of body. A new Korean name "Huk-jul-dom" is proposed for this species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.47-62
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• 1969

A goby, Synechogobius hasta (Temminck et Schlegel) was studied to investigate the food consumed and the biological change of the food organisms, and the fish were sampled from the closed tributary and the lower Part of the Naktong River, near Pusan, during the period from November of 1967 to December of 1968. The fish were sampled from four stations (Fig. 1), the total number of fish being 1,295 and they were grouped and analysed monthly. The content of the alimentary canal was analysed in three categories according to modified Nilsson's method (Dahl 1962) with a slight alteration: 1) The number of each item of stomach contents was counted and the percentage of each item in proportion to the total number of food organisms is indicated by the letter 'N' representing numerical percentage in Table 2. 2) The percentage of fish which contained any items of food organisms in proportion to the total number of fish caught in a given season is indicated by the letter 'O' representing frequency of occurrence. 3) Dominant groups of food items were selected and the percentage of the number of each dominant item in proportion to the number of the food organisms belonging to the dominant groups is indicated by the letter 'D' representing dominance. All food organisms were classified in 50 food item categories and then they were grouped in 13 main groups (Fig. 2-1), and they were further divided into 1) obligatory bottom animals, 2) organic drifts and 3) actively swimming forms; according to the conditions of the animal communities within the habitat. Since the majority of its food was composed of the obligatory bottom animals ($94.6\%$), the fish appeard to be a typical bottom feeder. And the dominant food organisms of the fish is generally determined by the local composition of the benthic fauna within the fish habitat. And their seasonal rhythm occurs among the food organisms in the stomach by the biological interaction. Locality variation in the population of the same food organism occurs due to the difference of food organisms in the habitat of the fish at Seonam and Garak, and at Seongsan and Hadan the condition of the niche for the fish in the both regions seems to be the same since the composition and the seasonal variation of the organisms were the same. The results may be summarized as follows: 1) The goby mainly feed on the animals of bottom fauna, and the food organisms are deter-mined by the food compositions within the habitat. 2) Seasonal variation of the stomach content shows the seasonal rhythm due to the biological variation of the population and their interaction. 3) The goby shows no preference on specific food, and the food is composed of a variety of animals. 4) Major food items of the goby are Polychaeta, Palaemon modestus, Isopoda, Gammaridea, Insecta (nymphs and larvae), Ilyoplax deschampsi, and Paratye compressa. 5) Logitudinal succession oil the population of the food organisms is apparently recognized within the community of Seongsan, Garak and Seonam. 6) The goby begins to descend toward the estuary and sea around April when the water temperature reaches $20^{\circ}C$, and they begin to return to river waters in September.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.676-685
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• 2003

Seasonal variation of the fishery resource in the shallow waters of Ganghwado tidal flat was investigated using monthly collected samples with a fence net from June 1998 to May 1999. Thirty-six species were found including 27 fish species, 6 crustaceans, and 3 molluscs. Of the fish, Konosirus punctatus, Sardinella zunasi Liza haematocheila and Synechogobius hasta dominated in the number of individuals $(92.1\%)$ and in biomass $(94.5\%).$ A few number of resident species, such as L. haematocheila and S. hasta, were collected only during the cold months. As the water temperature increased in the spring, the adult migratory fish such as K. punctatus and S. zunasi, were collected. In the summer, the juvenile fish recruited in the shallow water showing a peak in fish abundance. The data suggested that they grew until late autumn before moving to deeper waters for over-wintering. The principal component analysis showed that the seasonal variation in species composition was principally determined by water temperature and/or water temperature related factors. The species composition of the fish assemblage in the study area suggested that these species are highly adapted to extreme seasonal temperature variation and high water turbidity.

• Korean Journal of Ichthyology
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• v.17 no.2
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• pp.142-147
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• 2005

To research changes in the fish community of intertidal zones in relation to the construction of the Saemangeum tidal embankment, fishes were collected in the tide pools of Naechodo, Gunsan-si, and of Haechang, Buan-gun in Jeollabuk-do, every month from December 2002 to October 2004. Based on the fishes collected and data from previous studies show that in the tide pools of Haechang, the number of species decreased, and the dominant species is Tridentiger trigonocephalus, as before. However, in the tide pools of Naechodo, the number of species decreased, and the dominant species changed from T. trigonocephalus to Synechogobius hasta. Favonigobius gymnauchen, which inhabits sand-beds, decreased remarkably. Meanwhile, in the intertidal zone of Haechang, young black porgy were caught in large quantities, while in the intertidal zone of Naechodo, young Acanthopagrus schlegelii and Lateolabrax japonicus, which had been caught in a large amounts between 1994 and 2000, were not caught. The results are thought to show that the intertidal zone of Naechodo, Gunsan-si, had more deposits by tide flats than that of Haechang, Buan-gun, which drastically changed the habitat of its fish community.