• Korean Journal of Environmental Biology
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• v.32 no.2
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• pp.112-117
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• 2014

Predation efficiency and preference of the hydrophilid water beetle, Hydrochara affinis (Coleoptera: Hydrophilidae), larvae on two mosquito species, Culex pipiens molestus and Ochlerotatus togoi, were tested under laboratory conditions. Experiments were conducted in a transparent cylindrical plastic container (diameter, 100 mm; height, 40 mm; water level, 15 mm) for 24 hours (16 h, light; 8 h, dark) at $25^{\circ}C$. The predation efficiency of H. affinis on mosquito larvae was investigated under various prey conditions (1, 2, 4, 8, 16, 32, 64, and 128 larvae) with five replicates. Further, in order to investigate the prey preference on two mosquito species, each 32 larvae of C. pipiens molestus and O. togoi were provided simultaneously for the first instar larva of H. affinis with 5 replicates. As a result, the predation curves of H. affinis on two mosquito species were logarithmic; and the number of consumed prey increased as the number of predator instars were increased. As predicted from the predation curves, the estimated maximum number of C. pipiens molestus and O. togoi consumed by a third instar larva of H. affinis per a day was 926 and 304 larvae, respectively. As predicted from the Holling's disk equation, the differences in consumed prey number between predator instars and prey species were caused by handling time rather than attack rate. Handling time decreased rapidly as the predator larvae grew, and that of O. togoi was twice longer than that of C. pipiens molestus.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.199-200
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• 2003

After more than 5 years of turbot culture in China, low percent survival and high occurrences of abnormally pigmented juveniles are still major problems for fish farmer. Much research has been directed toward determining the optimal feeding strategies and nutritional requirements for marine flatfish larvae, and considerable advances have been made. The most common live feeds include :Artemia, rotifer and copepods. (omitted)

• Journal of Aquaculture
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• v.15 no.2
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• pp.79-86
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• 2002

This study is the first attempt to understand the feeding physiology of a sea-urchin larva on a red-tide dinoflagellate. Fifteen day old larvae of S. intermedius capture C. polykrikoides cells by localized reversal of ciliary beats. No failure to transporte the algal cells from theciliated band to mouth and no rejection at the mouth suggest that C. polykrikoides has no feeding deterrence to S. intermedius larvae. The trend obtained for the clearance rate of S. intermedius larvae is similar to that of other sea urchin larvae. Thus, the clearance rate decreased as the algal concentration increased. Maximum clearance rate of S. intermedius on C. polykrikoides was 17.7 $\mu l$/larva/hr. Ingestion rate rapidly increased at lower algal concentrations and saturated at higher concentrations. There was no inhibition in ingestion rate at the highest prey concentration of ca. 3000 cells/ml. Maximum ingestion rate of S. intermedius on C. polykrikoides was 131 ngC/larva/d, which is higher than that reported for the larvae of the mussel Mytilus gal-lotrovincialis, but lower than that of the ciliate Strombidinopsis sp. The grazing rate, calculated by combining the field data on algal abundances with experimental data on ingestion rate, suggests that due to its low abundance, sea urchin Iarva has no significant grazing impact on C. polykrikoides population.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.4
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• pp.498-506
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• 2015

We examined the feeding habits of larval Clupea pallasii using 148 specimens collected from December 2010 to April 2011 in the Nakdong River estuary, Korea. We found that larval C. pallasii [8.3-26.0 mm NL (notochord length)] are carnivorous, consuming mainly copepods, rotifers, cirripeds, and free-living flatworms (Macrostomida). Their diet also include small quantities of shrimp nauplii, tintinnids, cladocerans, and larval bivalves, among other food sources. To evaluate ontogenetic changes in dietary composition, we split larvae into four size groups: 8-12 mm, 12-16 mm, 16-20 mm, and > 20 mm NL. Rotifers were the most important prey items for the smallest group, but all other groups predominantly consumed copepods. The largest group frequently preyed on rotifers, cirripeds and flatworms, in addition to copepods. Larvae also showed bi-modal feeding, with peaks in the late afternoon and at midnight, wherein the mean number of prey per individual peaked at 1,800-1,900 h.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.2
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• pp.160-167
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• 2014

The feeding habits of Tridentiger bifasciatus were studied using 733 individuals collected in the tidal creek at Sangnae-ri, Suncheon, Korea, using a push net, monthly, from April 2011 to March 2012. The standard length (SL) of the specimens ranged from 1.5 to 8.2 cm. The stomach content analysis indicated that T. bifasciatus consumed mainly amphipods, such as Corophium sp., while copepods, polychaetes, and shrimps were other important prey species. In addition T. bifasciatus ate small quantities of crab larvae, fish, gastropod larvae, and insects. T. bifasciatus is a generalist that feeds on various zoobenthos, including fish. T. bifasciatus underwent an ontogenetic dietary shift. Smaller individuals (1-2 cm SL) fed mainly on amphipods. The proportion of amphipods decreased as body size increased, whereas the consumption of polychaetes increased gradually. The seasonal variation in the diet composition of T. bifasciatus was significant. Insects were common prey during summer, while the amounts of other prey, including polychaetes, were similar during spring, autumn, and winter.

• Fisheries and Aquatic Sciences
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• v.7 no.2
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• pp.84-89
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• 2004

Feeding habits of Sillago japonica collected from in an eelgrass (Zostera marina) bed in Jindong Bay, Korea were studied. S. japonica was a carnivore which consumed mainly gammarid amphipods, polychaetes, bivalves, caridean shrimps and crabs. Its diets also included a small amount of fishes, copepods and caprellid amphipods. The diet of S. japonica underwent significant size-related changes; small individuals (<5cm SL) fed mainly on gammarid amphipods and crab larvae, while proportion of polychaetes and bivalves increased with increasing fish size and gammarid amphipods were also important prey for medium size individuals (5.1-9.9cm SL). The large individuals (>10cm SL) ate polychaetes, caridean shrimps and crabs. The dietary breadth of S. japonica were varied with size. The diet of S. japonica also underwent seasonal changes that could be related to differences in prey availability; gammarid amphipods were mainly consumed in spring and polychaetes in summer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.4
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• pp.393-398
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• 2013

The purpose of this study was to determine how an ornamental fish, such as the fighting fish, Betta splendens would respond to the use of freshwater live-prey, such as rotifers Brachionus calyciflorus and water fleas Moina macrocopa. Ingested quantity, digestive velocity and somatic growth were compared between larvae fed a freshwater rotifer and those fed boiled yolk. Food efficiency and somatic growth were compared between larvae that were fed freshwater water fleas and those fed a micro-diet developed for flounder ($250{\mu}m$, I-hwa Ltd.). The number of rotifers ingested by larvae reached a maximum of 191 per day. However, based on the number ingested per hour and the digestive velocity of consumed rotifers, the maximum ingestible and digestible number of rotifers was calculated to be 272 per day. A maximum of 67 individuals (mean, 49.8 individuals) could be completely digested within the 1-h period from 90 to 180 min after feeding. Somatic growth was enhanced in larvae that were fed rotifers compared to those fed boiled yolk. Larvae exhibited greater growth at rotifer densities of 30 and 40 per mL than at lower densities. Among the water-flea (M. macrocopa and Bosmina sp.) and micro-particle diets, feeding with M. macrocopa resulted in the greatest somatic growth of larvae during the water-flea feeding stage.

• Korean Journal of Ichthyology
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• v.9 no.2
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• pp.221-227
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• 1997

Feeding habits of Leiognathus nuchalis collected from the eelgrass bed in Kwangyang Bay from January 1994 to December 1994 were studied. Leiognathus nuchalis was a carnivore which mainly consumed copepods and crab larvae. Its diets included small quantities of polychaetes, amphipods, mysids, caridean shrimps. It showed ontogenetic changes in feeding habits. In an initial feeding stage, copepods were major food organisms. However, crab larvae and polychaetes were heavily selected with increasing fish size. Although copepods and crab larvae were major prey organisms for all seasons, the relative proportion of these two food items changed with season.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.3
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• pp.368-376
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• 2015

The Feeding habits of larval Liparis tanakae collected from the Nakdong River estuary were studied. L. tanakae [3.8-10.6 mm notochord length(NL)] was a carnivore thatconsumed mainly copepods. Its diet also included small numbers of free-living flatworms (Macrostomida), tintinnids, cladocerans, and polychaetes larvae. To evaluate ontogenetic changes in dietary composition, three size groups were designated: 3-5, 5-7, and >7 mm. Copepods were the most important prey items for all size groups. The smallest size group frequently preyed on polychaete and bivalve larvae, along with copepods. As notochord length increased, the numbers of cladocerans and Macrostomida increased relative to those of polychaete and bivalve larvae.

• Korean Journal of Ichthyology
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• v.26 no.4
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• pp.349-354
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• 2014

The diet composition of bullet mackerel, Auxis rochei was studied using 200 specimens collected from December 2013 to May 2014 in the coastal waters of Iloilo, Philippines. The size of A. rochei ranged from 11.1 to 31.2 cm in fork length (FL). A. rochei was epipelagic feeder that consumed mainly fishes. In addition, A. rochei consumed shrimps, copepods, crab larvae, amphipods and cephalopods. The diet also included small quantities of stomatopods, bivalves, and ostracods. Also, analysis of the prey-specific abundance against the frequency of occurrence shows that A. rochei have a narrow food niche, and are specialized feeder with fish as their dominant prey. Although fishes were the primary in food consumed by all size class. The fishes gradually increased with body size.