This study investigates the relationship between cicada emergence patterns and climatic variables (temperature and humidity) in two urban parks in Seoul, Asian Park and Cheongdam Park. Weekly collections of cicada exuviae were conducted during the summers (June to August) from 2015 to 2017 to analyze emergence rates and their associations with climatic factors. A total of six cicada species were identified, with Hyalessa maculaticollis being the dominant species in Cheongdam Park (76.2%) and Cryptotympana atrata in Asian Park (54.3%). Emergence rates increased from mid-July, peaked in early August, and exhibited an overall upward trend during the study period. The observed differences between the parks appear to stem from variations in microclimatic conditions. Asian Park, characterized by open and flat urban landscapes, consistently recorded higher average temperatures over the three years. In contrast, Cheongdam Park, with its cooler oak-dominated, semi-forested environments, maintained more consistent microclimatic conditions within the urban setting. This study highlights the role of cicada emergence patterns in reflecting urban microclimatic conditions and provides baseline data for understanding the ecological impacts of urbanization and climatic variability.

Evaluating the ecological risks of living modified organisms (LMOs) before their commercial release is essential for safeguarding biodiversity and ecosystem stability. LMO confined field trials offer controlled environments that simulate natural conditions, enabling researchers to assess ecological impacts, particularly on non-target organisms such as arthropods. This study investigated the distributional patterns of arthropods within the Ministry of Environment’s LMO confined field facility in Seocheon, South Korea, over a 2-year period (2020-2021), to establish baseline ecological data prior to LMO environmental release experiments. Arthropods were collected across eight survey rounds using sticky traps, aspirators, and sweep nets, and identified using national taxonomic references. A total of 132 species (2,309 individuals) in 2020 and 154 species (3,352 individuals) in 2021 were recorded, with an overall total of 263 species across both years. Hemiptera was the most dominant order across both years, while Coleoptera and Diptera showed marked declines in 2021. In contrast, Araneae, Hymenoptera, Lepidoptera, Orthoptera, and Odonata increased substantially. Moreover, 104 species not observed in the 2020 survey were newly identified during the 2021 field survey. Dominant species also shifted between years, suggesting that local environmental factors and seasonal dynamics influence community composition. The arthropod dataset established through this study can serve as an important ecological reference for future ecological risk assessments of LMOs and the monitoring of non-target organisms.

Synchronous emergence is a widespread adaptive strategy in cicadas, yet the proximate cues governing its timing in urban environments remain poorly understood. We examined the emergence phenology of three common urban cicada species (Cryptotympana atrata, Hyalessa maculaticollis, Graptopsaltria nigrofuscata) across two urban parks with contrasting habitat structure (a closed-canopy urban forest park vs. an open urban park) in Seoul, South Korea, over three summers (2015–2017). Despite interannual variation in rainfall amount and timing, peak emergence consistently occurred about two weeks after the monsoon rainfall peak. Poisson generalized estimating equation (GEE) analyses confirmed that antecedent precipitation at a 2–3-week lag significantly increased emergence counts across all three species, while precipitation one week prior had no significant effect. Emergence synchrony varied among species and habitat conditions, but the rainfall–emergence lag relationship was robust across years and sites. These findings demonstrate that precipitation timing is a key driver of peak cicada emergence in urban habitats. As East Asia experiences increasingly variable monsoon rainfall under climate change, understanding precipitation-based phenological cues will be essential for predicting the dynamics of urban insect populations.