• Korean Journal of Environmental Biology
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• v.24 no.3
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• pp.300-305
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• 2006

Jassa slatteryi was redescribed as a new record to Korean fauna, accompanied by the morphological account in comparison with Jassa falcata Montagu, 1808. This work was based on the specimens which were collected from the screw of the international trade ship, named Hanjin, anchored in Samcheon-po bay of the south coast of Korea in 2004.

• The Korean Journal of Zoology
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• v.26 no.2
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• pp.135-153
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• 1983

Studies of fouling organisms in Deukryang Bay in 1981 showed that amphipod crustaceans comprised the most abundant zoological group. Three tubicolous gammaridean amphipods, Jassa falcata (Montagu, 1808) Corophium acherusicum (Costa, 1857) and Ericthonius brasiliensis (Dana, 1853) were described. They formed great masses of silty tubes attached to plastic and cement experimental plates. The ecological aspects of these fouling organisms have been also discussed.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.3
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• pp.125-132
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• 2007

We estimated the distribution of predator-prey interaction strengths for 12 species of herbivores (including amphipods, isopods, gastropods, and sea urchins) and made a regression model that may be applicable to other species. Laboratory experiments were used to determine per capita grazing rate (PCGR; g seaweeds/individual/day). Relationship between the biomass of individual grazers and fourth-root transformed PCGR was fitted to power curve ($y=0.2310x^{0.3290}$, r=0.8864). This finding supported that the grazing efficiency was not even as individual grazers increase in size (biomass). Therefore, the biomass-normalized PCGR was estimated and revealed that smaller size herbivores were more effective grazers. Grazing impact considering density of each taxon was calculated. The sea hare Aplysia kurodai had greatest grazing impact on the seaweed bed and the sea urchin Strongylocentrotus nudus and S. intermedius were ranked in descending order of the impact. The amount of seaweed grazed by the amphipod Elasmopus sp. (>4,000 $ind./m^2$) and Jassa falcata (>2,000 $ind./m^2$) were 3.435 and $1.697mg/m^2/day$ respectively. The combined grazing amount of herbivores was $5,045mg/m^2/day$ in the seaweed bed. Although sea hare and sea urchin had strong impacts on seaweeds, the effects of dense, smaller species could not be seen as negligible. Surprisingly, the calculated grazing potential of sea urchins with a mean density of 3 $ind./m^2$ exceeded the mean production of seaweed cultured in domestic coastal waters in Korea (ca., 5 ton/ha). Small crustaceans were also expected to consume up to 16% of the seaweed production if their densities were rising under weak predation conditions. Considering that the population density of herbivores are strongly controlled by fish, human interference like overfishing may have strong negative effects on persistence of seaweeds communities.