• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.27 no.3
• /
• pp.19-28
• /
• 2024

The purpose of this study is to investigate the habitat of Luciola unmunsana to understand the status of land snails, which are the larvae prey, and to evaluate the effects of larval feeding preferences and prey size for the restoration of the L. unmunsana habitat as a basis for future restoration projects. The research methods included field surveys of the habitat and laboratory experiments on feeding preferences using three types of land snails (Allopeas clavulinum kyotoense, Euphaedusa fusaniana, Pupinella rufa) observed in the habitat. Field surveys of 13 L. unmunsana habitat sites revealed a total of 24 land snail species. The experimental results regarding the larvae prey were analyzed for statistical significance of feeding preferences using Chi-square tests and independent sample t-tests. Consequently, larvae showed the highest preference for A. c. kyotoense, with statistically significant differences in feeding preferences (p<0.05). Also, statistically significant differences were observed in the size between the land snails that were eaten as prey and those that were not eaten. This research can deepen the understanding of the feeding preferences of L. unmunsana larvae and provide practical guidelines for the effective conservation and restoration strategies of the firefly habitat.

• Journal of Ecology and Environment
• /
• v.47 no.4
• /
• pp.168-176
• /
• 2023

Background: Many insectivorous bats have flexible diets, and the difference in prey item consumption among species is one of the key mechanisms that allows for the avoidance of interspecies competition and promotes coexistence within a microhabitat. In Korea, of the 24 bat species that are known to be distributed, eight insectivorous bats use forest areas as both roosting and foraging sites. Here, we aimed to understand the resource partitioning and coexistence strategies between two bat species, Myotis ikonnikovi and Plecotus ognevi, cohabiting the Mt. Jumbong forests, by comparing the differences in dietary consumption based on habitat utilization. Results: Upon examining their dietary composition using the DNA meta-barcoding approach, we identified 403 prey items (amplicon sequence variants). A greater prey diversity including Lepidoptera, Diptera, Coleoptera, and Ephemeroptera, was detected from M. ikonnikovi, whereas most prey items identified from P. ognevi belonged to Lepidoptera. The diversity index of prey items was higher for M. ikonnikovi (H': 5.67, D: 0.995) than that for P. ognevi (H': 4.31, D: 0.985). Pianka's index value was 0.207, indicating little overlap in the dietary composition of these bat species. Our results suggest that M. ikonnikovi has a wider diet composition than P. ognevi. Conclusions: Based on the dietary analysis results, our results suggests the possibility of differences in foraging site preferences or microhabitat utilization between two bat species cohabiting the Mt. Jumbong. In addition, these differences may represent one of the important mechanism in reducing interspecific competition and enabling coexistence between the two bat species. We expected that our results will be valuable for understanding resource partitioning and the coexistence of bats inhabiting the Korean forests.

• Fisheries and Aquatic Sciences
• /
• v.27 no.10
• /
• pp.654-664
• /
• 2024

This study thoroughly investigated the diet composition and feeding habits of black rockfish, Sebastes inermis along the Yeosu Coast, South Korea. The stomach content of S. inermis was dominated by shrimp (Acetes japonicus and Crangon hakodatei) and brachyura (Charybdis bimaculata and Charybdis japonica). Shrimp was the dominant prey throughout the seasons, with an increase in fish consumption observed during autumn. Predator size and sampling period influenced the average degree of stomach fullness in black rockfish; however, the significance of fish as prey increased with increasing size. Dietary overlap analysis demonstrated a high overlap among smaller size classes and a low overlap between smaller and larger size classes. The results of this study indicate that black rockfish are specialist predators of shrimp.

• Korean Journal of Ecology and Environment
• /
• v.37 no.1 s.106
• /
• pp.130-136
• /
• 2004

In the present study, prey preference of juvenile fishes was examined using an experimental approach. Zooplankton composition, as a prey of the fish, was evaluated by taking into account the species as well as body size of juveniles in the aquarium. The predation of juvenile fishes is known to be an important factor in changes of zooplankton communities. In some previous studies at the regulated Nakdong River, the collapse of large cladcoerans and an increase in the rotifer population by selective predation during spring and summer were observed. This study focused on the predation of juvenile fishes such as Hyporhamphus sajori, Rhinogobius brunneus, and Opsariichtys uncirostris amurensis on zooplankton community structure in mesocosm scale experiments. These fishes selected the cladoceran Moina micrura with highest individual preference value (Manly/Chesson index)among zooplankton prey in the experimental aquarium. When the size-selective prey preferences of the juvenile fish were compared, both small (body size <2 cm) and large (body size >2cm) juveniles of O. uncirostris positively selected M. micrura. In the outdoor experimental tanks, juvenile fishes consumed the cladoceran M. micrura, resulting in an high abundance of the rotifer, Polyarthra spp. The results suggest that juvenile fish predation may play an important role in regulating the zooplankton community structure by reducing the cladoceran density and increase of rotifers in the Nakdong River during spring and summer.

• Animal cells and systems
• /
• v.9 no.1
• /
• pp.13-18
• /
• 2005

Cannibalism plays important roles at the levels of both individual and population. To enhance overall rate of successful survival and reproduction, salamander larvae may have evolved to consume both conspecifics and heterospecifics. Consuming conspecifics could result in decreased inclusive fitness possibly by killing relatives. In several salamander species, discrimination of salamander larval siblings from non-siblings and heterospecifics to avoid such a risk has been reported. To determine whether the Korean salamander larvae consume non-siblings more often than siblings and to analyze prey preferences of the salamander larvae in several different experimental conditions, a series of foraging experiments was conducted in the laboratory. We found that 1) large cannibal larvae preyed on small sibling more often than small non-sibling in a mixed group of sibling and non-sibling, 2) cannibal larvae prefered to consume live, weak, and small larvae to dead, healthy, and large larvae, and 3) cannibal larvae consumed heterospecific tadpoles more often than conspecific nonsibling larvae in a mixed group. In addition, the larval density was positively correlated with the occurrence of spacing behavior, one of the agonistic predator behaviors among salamander larvae.

• Korean journal of applied entomology
• /
• v.42 no.3
• /
• pp.197-201
• /
• 2003

These studies were carried out to investigate the amounts and preferences of Oligota kashmirica benefica to 3 species of phytophagous mites and cannibalism. The number of mites consumed by an adult beetle tended to increase as prey density and temperature go up. In the constant temperature of 25$^{\circ}C$, average number of consumed adult mites by an adult of O. kashmirica benefica to Panonychus citri, Tetranychus urticae and T. kanzawai were 21.9, 13.5, and 14.1 for a day, respectively. The number of mites consumed by larva of O, kashmirica benefica tended to increase as the larva grow up. First, 2nd and 3rd larva of the beetle consumed 2.8, 11.2 and 25.4 adult of citrus red mite (P. citri) for a day, respectively. Total number of mites consumed during larval stage (5 days, 25$^{\circ}C$) to P. citri, T. urticae and T. kanzawai were 77.7, 61.3 and 73.0, respectively. The larva and adult beetle did not prefer specific species in the P. citri, T. urticae and T. kanzawai, and when there was no diet, few incidents of cannibalism between different developmental stage were observed.

• Korean Journal of Ichthyology
• /
• v.33 no.4
• /
• pp.278-286
• /
• 2021

The habitat characteristics and feeding ecology of the Siberian stone loach Barbatula toni were investigated in Bukcheon (Stream), Eocheonri, Ganseong-eup, Goseong-gun, and Gangwon-do, Korea from January to December 2013. B. toni lived in rapids or slow rapids from the upper stream to downstream, with the largest number of inhabitants in the middle-downstream regions. As a result of analyzing habitat preferences by age, 0+ and 1+ to ≥3+ showed differences. Ages of 0+(juveniles) lived mainly in rapidly flowing water (37.6±26.79 cm/sec) and low water depths (13.3±9.47 cm) in the pebble bottoms (substratum particle size 9.5±6.66 cm), but ages 1+ to ≥3+ lived mainly in relatively slowly flowing water (13.3±17.33 cm/sec) and relatively deep depths (25.9±10.31 cm) in stone and large stone bottoms (substratum particle size 18.0±7.63 cm). B. toni was mainly eaten from March to December when the temperature was above 5℃, and the amount of food eaten peaked in June and October. Their main food sources analyzed by the index of relative importance (IRI) included Diptera (57.0%), Ephemeroptera (29.3%), and Trichoptera (13.5%). The juveniles (age 0+) fed on small-sized prey such as Diptera and Trichoptera whales, but as they grew, they mainly ate large-sized Ephemeroptera. These feeding habits and changes in food according to the growth of B. toni were very similar to those of sibling species, B. nuda.