오대산국립공원 내 뱀류 로드킬 분포현황 및 발생예측 모델링

김석범,박일국,박대식,Kim, Seok-Bum,Park, Il-Kook,Park, Daesik 한국환경생태학회 2022 한국환경생태학회지 Vol.36 No.5

오대산국립공원 내 뱀류 로드킬의 발생 경향 파악 및 예방을 위하여 2006-2017년 사이 공원 내에서 발생한 뱀류 로드킬 자료를 확보 및 분석하였고, 잠재적 발생지 예측을 위하여 종분포모델을 제작하였다. 연구기간 동안 뱀류 로드킬은 600m 대의 양쪽 환경이 산림-수계인 도로에서 가장 많이 발생하였다. 모델링 결과에서 뱀류 로드킬 발생 가능성은 고도 700m 이하의 하천과의 거리가 25m 부근인 완만한 경사의 도로의 로드킬 발생확률이 높게 나타났다. 국립공원 내 주요 로드킬발생 예측지역은 국도 6호선 도로 위 공원 남쪽 경계로부터 약 2.2km 지역과 약 11.7km 지역이, 지방도 446호선 도로 위 공원 남쪽 경계로부터 약 3.44km 지역이었다. 본 연구결과는 해발고도 700m 이하 수계와 인접한 도로 주변에 우선적으로 대체 일광욕 장소, 생태통로 및 도로의 유입을 막는 울타리의 설치가 산림에서 뱀류 로드킬을 줄이는 효과적인 방안이 될 것을 제시한다. In this study, we collected snake roadkill data from 2006 to 2017 and developed a species distribution model to identify the pattern of snake roadkill and predict the potential hotspot of snake roadkill in the Odaesan National Park of South Korea. During the study period, snake roadkills occurred most frequently on the road, which passes through between forest and stream at an altitude of about 600 m. The modeling result showed that the occurrence probability of snake roadkill was high on a road with a gentle slope at a distance of 25 m from the stream and an altitude of 600 m. The most susceptible regions for snake roadkill in the Odaesan National Park were located on National Route 6, about 2.2 km and 11.7 km away from the southern border of the park, and on Local Road 446, 3.44 km away from the southern border of the park. The results of this study suggest that providing alternative basking places and eco-corridors and installing protection fences that block the inflow of snakes into roads, preferentially around roads and streams at an altitude lower than 700 m would be an effective way of reducing snake roadkill in the Odaesan National Park.

Correlations between the Growth Period and Fresh Weight of Seed Sprouts and Pixel Counts of Leaf Area

( Daesik Son ),( Soo Hyun Park ),( Soo Chung ),( Eun Seong Jeong ),( Seong Min Park1 ),( Myong Kyoon Yang ),( Hyun Seung Hwang ),( Seong In Cho ) 한국농업기계학회 2014 바이오시스템공학 Vol.39 No.4

Purpose: This study was carried out to predict the growth period and fresh weight of sprouts grown in a cultivator designed to grow sprouts under optimal conditions. Methods: The temperature, light intensity, and amount of irrigation were controlled, and images of seed sprouts were acquired to predict the days of growth and weight from pixel counts of leaf area. Broccoli, clover, and radish sprouts were selected, and each sprout was cultivated in a 90-mm-diameter Petri dish under the same cultivating conditions. An image of each sprout was taken every 24 hours from the 4th day, and the whole cultivating period was 6 days, including 3 days in the dark. Images were processed by histogram inspection, binary images, image erosion, image dilation, and the overlay image process. The RGB range and ratio of leaves were adjusted to calculate the pixel counts for leaf area. Results: The correlation coefficients between the pixel count of leaf area and the growth period of sprouts were 0.91, 0.98, and 0.97 for broccoli, clover, and radish, respectively. Further, the correlation coefficients between the pixel count of leaf area and fresh weight were 0.90 for broccoli, 0.87 for clover, and 0.95 for radish. Conclusions: On the basis of these results, we suggest that the simple image acquisition system and processing algorithm can feasibly estimate the growth period and fresh weight of seed sprouts.

Predation of the Japanese keelback (Hebius vibakari Boie, 1826) by the Slender racer (Orientocoluber spinalis Peters, 1866)

Park, Il-Kook,Park, Jaejin,Park, Jiho,Min, Seong-Hun,Grajal-Puche, Alejandro,Park, Daesik The Ecological Society of Korea 2021 Journal of Ecology and Environment Vol.45 No.1

Background: The Slender racer (Orientocoluber spinalis Peters, 1866) has recently been reclassified to the new genus Orientocoluber from Hierophis. Ecological knowledge of this species is limited due to its highly mobile behavior. On 17 July 2020, we captured a female O. spinalis on Oeyeon Island, Boryeong-si, Republic of Korea, and collected its feces for a diet analysis. We observed snake scales from the collected feces and subsequently determined the prey species through morphological and molecular methods. Results: We initially hypothesized that the extracted fecal sample scales belonged to H. vibakari, due to their thin keel and rhombus shape. We also amplified H. vibakari DNA from the extracted fecal sample using Illumina sequencing methods. Our morphological and molecular results suggest that O. spinalis predates H. vibakari on Oeyeon Island. Conclusion: This is the first report of O. spinalis predating another snake species, ophiophagy, and implies that H. vibakari may be a crucial prey item for O. spinalis on Oeyeon Island.

First Report of Epibiont Barnacle Attached to Chinese Sea Krait (Laticauda semifasciata) in the Republic of Korea

Min-Woo Park,Jaejin Park,Il-Kook Park,Jongsun Kim,Il-Hun Kim,Daesik Park 한국양서ㆍ파충류학회 2022 한국양서·파충류학회 학술대회 Vol.2022 No.07

To date, more than 1,000 species of barnacles have been reported, and some barnacles spend most of their life attached to marine vertebrates. As their distribution patterns are as diverse as their species diversity, they can be important data for understanding the behavior or ecology of host organisms as epibiont. However, in Korea, further research is needed because studies on the relationship between barnacles and marine vertebrates are still insufficient. In this study, we report a barnacle attached to a Chinese sea krait (Laticauda semifasciata) caught in the sea of Korea. On September 7, 2016, in the sea near Udo Island, Jeju (33.56°N, 127.02°E), a total of 22 barnacles were found to attach to one L. semifasciata caught. We identified these barnacles as Conchoderma virgatum based on their morphological characteristics such as distinctive feature of the capitulum and peduncle, the number of capitulum with reduced 5 plates, and the number of 2 scutum in Y-shape. There are a total of two types of barnacles (C. virgatum and Platylepas ophiophilus) that have been reported to attach to L. semifasciata in the world. Attached barnacles, including the C. virgatum, may restrict the behavior of sea kraits, cause dysecdysis, or cause the secondary infection through epithelial tissue damage. Therefore, further study on the relationship between barnacles and marine reptiles might be needed.

Olfactory Responses of Male and Female Red-spelled Newts to Sex Pheromones from the Opposite Sex

Park, DaeSik,Park, Shi-Ryong The Korean Society for Integrative Biology 2002 Korean journal of biological sciences Vol.6 No.4

Functional characterization of sex pheromones in olfactory responses is essential for the study of chemical communications in amphibians. Using Y-maze olfactory preference tests, we have investigated the olfactory res-ponses of male and female red-spotted newts, Notophthalmus viridescens, to the crude extracts of the opposite sex's genial and cloacal pheromones. Both male and female cloacal pheromone extracts caused the opposite sex to initiate olfactory responses by leaving the starting area in the Y-maze, but only subject males exposed to female cloacal pheromone extracts completed olfactory choice by entering the side arm of the Y-maze which received the pheromones. For genial pheromone extracts, only female genial pheromone extracts induced initial olfactory responses from test males. Neither male nor female genial pheromone extracts made the oppo-site sex complete olfactory choice. Pre-exposure of test females to male pheromone extracts increased the likelihood of initial olfactory responses. The latency for initial olfactory responses of test females that were previously exposed to male genial extracts was significantly shorter than that of control females.

First Record of Laticauda semifasciata (Reptilia: Squamata: Elapidae: Laticaudinae) from Korea

Park, Jaejin,Kim, Il-Hun,Koo, Kyo-Sung,Park, Daesik The Korean Society of Systematic Zoology 2016 Animal Systematics, Evolution and Diversity Vol.32 No.2

The Chinese sea snake Laticauda semifasciata (Reinwardt in Schlegel, 1837) is newly reported from Korean waters based on three specimens collected from Jeju Island, Korea, in August, September, and November 2015. This is the first time that the genus Laticauda and subfamily Laticaudinae has been reported from Korean waters. The subfamily Laticaudinae has ventrals that are four to five times wider than the adjacent dorsals, which are unlike the ventrals that are similar or up to two times wider than adjacent dorsals in the subfamily Hydrophiinae. Laticauda semifasciata is distinct from other species because it has three prefrontals and its rostrals are horizontally divided into two. As the result of this report, four species (L. semifasciata, Hydrophis (Pelamis) platurus, Hydrophis cyanocinctus, and H. melanocephalus) of sea snakes have been reported in Korean waters.

First detection of ranavirus in a wild population of Dybowski's brown frog (Rana dybowskii) in South Korea

Park, Jaejin,Grajal-Puche, Alejandro,Roh, Nam-Ho,Park, Il-Kook,Ra, Nam-Yong,Park, Daesik The Ecological Society of Korea 2021 Journal of Ecology and Environment Vol.45 No.1

Background: Ranavirus is an emerging infectious disease which has been linked to mass mortality events in various amphibian species. In this study, we document the first mass mortality event of an adult population of Dybowski's brown frogs (Rana dybowskii), in 2017, within a mountain valley in South Korea. Results: We confirmed the presence of ranavirus from all collected frogs (n = 22) via PCR and obtained the 500 bp major capsid protein (MCP) sequence from 13 individuals. The identified MCP sequence highly resembled Frog virus 3 (FV3) and was the same haplotype of a previously identified viral sequence collected from Huanren brown frog (R. huanrenensis) tadpoles in South Korea. Human habitat alteration, by recent erosion control works, may be partially responsible for this mass mortality event. Conclusion: We document the first mass mortality event in a wild Korean population of R. dybowskii. We also suggest, to determine if ranavirus infection is a threat to amphibians, government officials and researchers should develop continuous, country-wide, ranavirus monitoring programs of Korean amphibian populations.

Differential Responses of Large and Small Male Red-spotted Newts, Notophthalmus viridescens, to Conspecific Chemical Cues

Daesik Park,Jeanette M. McGuire,Heather L. Eisthen 한국통합생물학회 2004 Animal cells and systems Vol.8 No.2

Male red-spotted newts, Notophthalmus viridescens, use chemical cues to locate and select potential mates. To investigate whether large and small males respond differentially to chemical cues from conspecifics, we conducted a series of two-choice Y- maze tests with odorant stimuli from two large females (LF/LF), one large versus one small female (LF/SF), and one large female placed with four males versus one small female (LF+4M / SF). We found that males responded more rapidly in a LF/LF choice situation than in those involving LF/SF or LF+4M/SF. In addition, small males chose more quickly than did large males. These results suggest that both body size and odorant context affect the speed of odorant responses. By responding differentially to conspecific chemical cues, small males may arrive earlier at a courting area, increasing their chances of successfully guarding and mating with a female.

O1factory and Sexual Attractiveness of Western Mosquitofish (Gambusia affinis) Exposed to the Commonly Used Insecticide Endosulfan

Park, Daesik,Propper, Catherine R.,Park, Shi-Ryong The Korean Society for Integrative Biology 2002 Korean journal of biological sciences Vol.6 No.2

To know whether a short-term exposure to a commonly used insecticide induces subtle negative toxic effects, female western mosquitofish, Gam-busia affinis, were exposed to 0.1, 0.5, and 1 pub endosulfan for one week and subsequently examined for their olfactory and sexual attractiveness to conspecific males. A short-term exposure to endosulfan did not impair the physical conditions investigated in this study nor did it disrupt olfactory attractiveness of female mosquitofish. However, 1 ppb endosulfan significantly reduced sexual attractiveness of exposed females. Test males showed significantly less copulation attempts with the exposed females. Our results suggest that in the field, a short term exposure of endosulfan may disrupt mating processes in non-targeted aquatic organisms.

The Olfactory Organ is Activated by a Repelling Pheromone in the Red-spotted Newt Notophthalmus viridescens

Park, Daesik,Propper, Catherine R. The Korean Society for Integrative Biology 2002 Korean journal of biological sciences Vol.6 No.3

The pheromonal repelling response occurs when a combination of female and male pheromones is found to be less attractive to courting males than are female pheromones alone. This repelling response may act to conserve a courting males’reproductive fitness by minimizing ma1e-male competition within a courting group. Recently, a Pheromonal repelling response was first reported for vertebrates in the red-spotted newt, Notophthalmus viride-scens. A male cloacal pheromone, a ∼33 kDa protein, was identified as a repelling pheromone. In this study, to determine whether both the main olfactory epithelium (MOE) and/or the vomeronasal organ (VNO) are activated by the repelling pheromone, we recorded electrical field potentials from both olfactory epithelia while applying the repelling pheromone. The repelling pheromone induced electrical responses from both olfactory organs, and the magnitude of the response was greater in the VNO than in the MOE. Our results suggest that both the VNO and MOE may be involved in the pheromonal repelling response.