• International Journal of Industrial Entomology and Biomaterials
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• v.47 no.1
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• pp.25-33
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• 2023

Solitary bees, such as Osmia cornifrons, O. pedicornis, O. satoi, and O. taurus (Hymenoptera: Megachilidae), have the potential for cost-effective and sustainable pollination, necessitating a comprehensive understanding of their ecological traits to implement effective fertilization strategies for various crops. This study investigated the nesting rate of Osmia spp. in different regions and altitudes, using various trap types, and found that the highest nesting rate occurred at altitudes of 300-399 m a.s.l. and showing a preference for bamboo-type traps, with the Andong region having the highest nesting rate overall, indicating the influence of altitude, habitat area, and trap type on the density of Osmia spp. nests. The distribution and diversity of the four Osmia spp. in different regions and altitudes revealed variations in their occurrence, with O. pedicornis having the broadest distribution rate, particularly at altitudes above 300 m a.s.l.. The present study found significant differences between species in the cocoon masses of O. cornifrons, O. pedicornis, and O. taurus, with region and altitude influencing the masses of each species too.

• Genomics & Informatics
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• v.20 no.3
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• pp.34.1-34.11
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• 2022

Multilevel analysis is an appropriate and powerful tool for analyzing hierarchical structure data widely applied from public health to genomic data. In practice, however, we may lose the information on multiple nesting levels in the multilevel analysis since data may fail to capture all levels of hierarchy, or the top or intermediate levels of hierarchy are ignored in the analysis. In this study, we consider a multilevel linear mixed effect model (LMM) with single imputation that can involve all data hierarchy levels in the presence of missing top or intermediate-level clusters. We evaluate and compare the performance of a multilevel LMM with single imputation with other models ignoring the data hierarchy or missing intermediate-level clusters. To this end, we applied a multilevel LMM with single imputation and other models to hierarchically structured cohort data with some intermediate levels missing and to simulated data with various cluster sizes and missing rates of intermediate-level clusters. A thorough simulation study demonstrated that an LMM with single imputation estimates fixed coefficients and variance components of a multilevel model more accurately than other models ignoring data hierarchy or missing clusters in terms of mean squared error and coverage probability. In particular, when models ignoring data hierarchy or missing clusters were applied, the variance components of random effects were overestimated. We observed similar results from the analysis of hierarchically structured cohort data.

• Korean journal of applied entomology
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• v.41 no.4
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• pp.263-267
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• 2002

A faunistic survey was conducted to find Osmia bees to be used as an effective pollinator in apple orchards. Collections were carried out from more than 50 selected sites in mountainous areas throughout Korea for 3 years (1996-98) with providing bundle of bamboo traps (6-8 mm of inner diameter) as Osmia nesting site. Five species of Osmia ：O. cornifrons (Radoszkowsky), O. pedicornis Cockerell, O. taurus Smith, O. satoi Yasumatsu et Hirashima and O. jacotti Cockerell, were collected at the rates of 39.9-51.7, 28.3-53.7, 5.5-19.1, 0.8-0.9 and 0.0-0.1%, respectively. And O. cornifrons and O. pedicornis were the dominants with over 80% of total Osmia collected through the collections. Out of those bees collected, rates of female were 29-43% for O. cornifrons. 10-12% for O. pedicornis and 22-43% for O. taurus. When the collection sites of the dominant 3 species were grouped in relation to altitudes above the sea level, about 50% or more bees were collected form the higher sites (500m or higher) while 20% or less were from the lower sites (200m or lower). When the bamboo traps were placed at the same sites continuously for 3 years, number of O. cornrfrons and O. taurus collected was slightly increased while that of O. pedicornis was drastically decreased year after year. Nesting by Osmia bees seems to have started at around early April, peaked at early May and ended by Mid June, while nest competing species of Sphecidae and Eumenidae started nesting at around early June, peaked at early July and ended by the Mid August.

• Journal of Ecology and Environment
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• v.31 no.4
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• pp.333-339
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• 2008

We investigated death rates, growth rates and recruitment of culms in two neighboring bamboo (Phyllostachys bamboosoides) stands nested in by two different bird species to analyze stand structure and to design conservation strategies. A third bamboo grove not used by birds, the Taewha stand, was included as a control stand. The bamboo stand occupied by birds in the family Ardeidae (the Ardeidae stand) had an approximately 1.5 times higher culm density than the stand occupied by birds in the family Corvidae (the Corvidae stand). The crude death rate and the number of newly emerged shoots were also higher in the Ardeidae stand than the Corvidae stand. The death rate for bamboo in the Ardeidae stand was not dependent on diameter at breast height (DBH) and was almost 40% for culms of all sizes, whereas most dead culms in the Corvidae stand were < 4 cm DBH. Consequently, we conclude that in the Ardeidae stand, density-independent causes of death are operating, while density-dependent factor are more important in the Corvidae site. The results of soil analysis in these stands suggest that the density-independent death pattern observed in the Ardeidae stand may be due to soil acidification resulting from wastes produced by the birds during breeding. On the other hand, the culm distribution and death patterns in the Corvidae stand suggest that the stand characteristics were not affected by the nesting birds. These results suggest that different conservation strategies must be applied to conserve bamboo groves used by ardeids and corvids for nesting.

• Korean System Dynamics Review
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• v.11 no.3
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• pp.105-126
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• 2010

The ecology of house swallow is closely related to the humans life because their life depend on the human settlements conditions and environments. 30 years ago house swallows are very common at the country side, but recently they are very rare. Almost the number of house swallows decrease as 1 of hundredth during 20 years. Why this dramatic population decrease are happening in the ecology of house swallow? The Population size impacted by many factors such as nesting, breeding, feeding, returning. The objective of this paper is to analyse the population dynamics of the ecology of House Swallow. This paper focuses on the important ecological changes-nests, foods, and return rates from wintering area-associated with recent country side development. In this paper, we explore the feedback loops of population dynamics and simulate the policy scenario model.

• Journal of Life Science
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• v.19 no.11
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• pp.1611-1616
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• 2009

This study was conducted to determine the characteristics in breeding of the little tern Sterna albifrons in Shinja-do and Doyo-Deung in Nakdong estuary. The data was obtained in the middle and late 1990's and in the mid 2000's, which were analysed for the breeding information of the little tern. In Shinja-Do, a total of 638 nests were observed in 1995, and the average numbers of eggs laid per nest were 2.48. In 2004 and 2005, 94 and 456 nests were observed, and the average number of eggs laid per nest was 2.16 and 2.53, respectively. There was a significant difference between the average numbers of eggs laid per nest for the 3 respective years. In Doyo-Deung, a total of 269 nests were observed in 1998, and the average number of eggs laid per nest was 2.16. In 2004 and 2005, 1,023 and 1,123 nests were observed, and the average numbers of eggs laid per nest were 2.33 and 2.52, respectively. There was a significant difference (p<0.001) between the average number of eggs laid per nest as well. Hatching success rate by nesting site in Shinja-Do was calculated in 1995. Type A nest (nest located on dry sand land) showed a 56.8% success rate, and type B nest (nest located on the land with dwarf grass), type C nest (nest located on moist land) and type D nest (nest located on the land with shells) showed 55.3%, 36.6% and 59.3% success rates, respectively. The average hatching success rate in Shinja-Do was 54.5%. The most crucial factor for hatching failure was flood, especially, for the type C nests. The hatching success rate by the nesting site in Doyo-Deung showed an average of 73.2%. It was high in type D nest (83.8%) and type A nest (75.9%), and low in type C nest (59.7%). Again, the most crucial factor for hatching failure was flood, especially, for the type C nests. Nakdong estuary has been through many changes over time, particularly in recent. Therefore, continuous efforts to keep it a breeding place for the little tern are urgently required, including overall management of land, protection of reef and sand, etc.