• The Korean Journal of Zoology
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• v.39 no.4
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• pp.387-392
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• 1996

All immature stages, eggs, larvae, and pupae of Korean Thiaspida, T. cribrosa and T. lewisii, are described and Illustrated for the first time. Two species belonging to genus Thiaspida In the subfamily Cassidlnae; T. cribrosa and T. lewisii.Observatiors on bionomics of immature stages and on their taxonomic charaders are also given.

• Korean Journal of Environment and Ecology
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• v.33 no.4
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• pp.402-407
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• 2019

In this study, we investigated the habitat characteristics of a reservoir in Gyeongju City, Gyeongbuk, in which a large group of Mauremys reevesii (endangered species Class II and natural monument No. 453 in Korea) was discovered. We examined the biotic and abiotic factors that directly and indirectly threaten the survival of M. reevesii within the habitat. The reservoir where M. reevesii was discovered was built for agriculture and surrounded by submerged trees, dam, forests, reeds, and farmland (paddy field). All of the M. reevesii were found only in the submerged trees on the north side of the reservoir. We found 28 M. reevesii (8 juveniles) and 21 M. reevesii (16 juveniles) from field surveys on May 10th and August 9th, 2018, respectively. A number of red-eared sliders (Trachemys scripta elegans) and American bullfrogs (Rana catesbeiana), which threaten the survival of M. reevesii, were also found in and around the reservoir. Moreover, there were signs of excavation of cultural asset, chemical fertilizer, and household garbage, all of which are considered to be major threats to the survival of M. reevesii, all over the reservoir. Newborn turtles in this year were not observed. However, we estimated that natural breeding had sufficiently occurred since we observed many young turtles in the reservoir. Furthermore, the presence of young T. s. elegans individuals can be a persistent problem for M. reevesii as they are competing species. In conclusion, in-situ conservation method should be considered for protecting the endangered turtle and their habitat.

• Journal of Environmental Impact Assessment
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• v.32 no.2
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• pp.83-93
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• 2023

This study was conducted to clarify the environmental variables that affect the appearance of Mauremys reevesii and to understand the relationship between M. reevesii and the variables. Habitat environmental survey was implemented by selecting 17 environmental variables considering ecological characteristics of M. reevesii in the main reservoir in Gurye-gun, the Republic of Korea. And the habitat data on the presence and absence of M.reevesii were analyzed statistically. The habitat suitability model of M. reevesii was described in following equation : logit (p) = -3.68 + (0.17 × leaf litter depth) + (1.55 × vegetation coverage of overstory on land) + (0.71 × coverage of midstory on land) + (0.96 × vegetation coverage of understory on water). This information gained is valuable for better understanding the distribution and how to conserve and promote populations of M. reevesii occurring in the Republic of Korea.

• Korean Journal of Environment and Ecology
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• v.37 no.3
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• pp.192-197
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• 2023

This study was conducted to determine whether the difference in egg hatching temperature of Korea Reeves' turtle (Mauremys reevesii) at the artificial nursery of Seoul National Grand Park affects the incubation period and growth. A total of 201 eggs were incubated at 26 ℃ (n=89), 28 ℃ (n=75) and 32 ℃ (n=37). The incubation period of eggs showed significant differences according to the hatching temperature. In this study, the higher the hatching temperature, the higher the hatching rate. The incubation period of the eggs hatched at 26 ℃, 28 ℃ and 32 ℃ was 66.1 (±4.0, n = 52) days, 65.3 (±3.3, n = 44) days and 58.8 (±7.7, n = 31) days, respectively. Eggs incubated at 32 ℃ (83.8%) had a higher hatching success than those at 26 ℃ (58.4%) and 28 ℃ (58.7%). The body mass of 14-day-old hatchlings incubated at 32 ℃ was greater than those incubated at 26 ℃ and 28 ℃. However, there was no significant difference in the mean body mass of 180 and 270-day-old turtles hatched at these different temperatures. This study showed that the hatching temperature significantly affected the incubation period and body mass in the early life of the Korea Reeves' turtle (M. reevesii).

• The Korean Journal of Soil Zoology
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• v.8 no.1_2
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• pp.58-60
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• 2003

The author has observed a reeves turttle (Chinemys reevesii) obtained from a market on Jeonju city, Korea. The turttle laid 5 eggs during the period from 31st Aug. to 5th Sep., 2003. The range of egg sizes was 3.5-3.9${\times}$1.9-2.4 cm and that of egg weights, 7.2-10.9 g. It seems to be difficult to distinguish the reeves tuttle eggs from the red-eard tuttle (Pseudemys consina consina) eggs because they are so similar each other in size and shape. He could not hatch out the reeves tuttle eggs.

• Korean Journal of Environment and Ecology
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• v.37 no.1
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• pp.76-85
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• 2023

This study aimed to understand social interactions by observing the courtship and attack behavior between individuals of 15 (6 females and 9 males) Reeves' turtle (Mauremys reevesii) in captivity in the Wolchulsan National Park. CCTV was installed in the study area from May 18, 2020 to October 19, 2020 and recorded 3 days a week (24 hours/day) for a total of 64 days and analyzed at intervals of 10 minutes per hour. Male turtle courtship was observed 884 times in total, with the heaviest females receiving the highest courtship frequency (357 times) and the smallest females receiving the least courtship (3 times). Of a total of observed 259 aggressive behaviors, 30 were for female to female, 81 for male to male, and 148 for female to male. Dominance hierarchy identified based on the result ranked females higher overall than males, and the larger the body, the higher the ranking. This study was the first in Korea to confirm individuals with high probability of reproduction through the frequency of courtship in the Reeves' turtle and investigate dominance hierarchy according to attack behavior. Our results can be used as reference behavioral data for managing and protecting the endangered Reeves' turtles and will help us understand their social structure.

• Korean Journal of Environmental Biology
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• v.41 no.2
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• pp.138-144
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• 2023

The main factor of biodiversity decline in major biological populations around the world is invasion of alien species. To protect native species, it is necessary to manage alien species. Recently, to eradicate ecosystem disturbance caused by alien species in Korea, many efforts have been made to capture individuals using nets and purchase captured individuals. However, there is no standard for classifying species due to the form of nest site or external characteristics of eggs of freshwater turtles. Thus, Mauremys reevesii eggs might be discarded due to mistaking as eggs of alien turtles. Based on more data, this study aims to compare and analyze external differences among eggs of Trachemys scripta elegans, Pseudemys concinna, and M. reevesii and use them as reference materials in the process of eradicating alien turtles. This study measured characteristics of eggs of the three turtle species. As a result of comparison, all variables of external characteristics of alien turtles and M. reevesii eggs showed significant differences. The shape of egg was also different, with eggs of T. scripta elegans and P. concinna showing a bicone shape and those of M. reevesii showing an ellipsoid shape. In conclusion, based on results of previous studies and the present study, eggs of M. reevesii, T. scripta elegans, and P. concinna are different in shape and structure. Thus, it is possible to distinguish between M. reevesii and invasive alien turtle using their eggs.

• Korean Journal of Environment and Ecology
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• v.31 no.4
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• pp.397-408
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• 2017

The purpose of this study is to identify the home range and habitat using pattern of the native species, Mauremys reevesii, and the exotic species, Trachemys scripta elegans, and to analyze the mutual competition relationship of the two species. This study was conducted at the Goldfish square pond, which is located in the upper part of the valley of Cheonggye mountain from August 2, 2010 to January 30, 2011. We used the three artificially proliferating M. reevesii and three T. scripta elegans which were inhabited in the ponds and reservoirs for monitoring study after attaching the transmitter to each of them. We measured the home range and the habitat utilization radius of three individuals of each species and the environmental factors such as temperature, humidity and soil and water temperature around the Goldfish square pond. As our results, it was analyzed that the M. reevesii and T. scripta elegans have a redundant ecological positions in various aspects such as limited sunbathing places, food resource utilization, hibernation place, etc. We also found that the relatively small M. reevesii was being pushed out of the competition by the relatively big. Further investigation of food competition and habitat utilization should be necessary for these two species for the natural habitats, their home range, food competition, and habitat utilization. The result of this study will be the basic data M. reevesii's restoration project.

• Korean Journal of Ecology and Environment
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• v.51 no.2
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• pp.168-173
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• 2018

Mauremys reevesii is a Korean endemic turtle, and designed as an endangered species and national monument in South Korea. Recently, the population of the species has been dramatically declining because of habitat destruction, pollution and illegal capture. Moreover, small population size, difficulty of securing individuals, and lack of research are factors that impede the effective management of the species. In this study, we tested the effect of individual breeding and feeding on the seven juveniles of M. reevesii. Our results showed individual breeding and feeding were guaranteed the effective growth and development. Noticeable growth was confirmed in both body weight and carapace length. Moreover, the size difference among the individuals appeared at the start of this study decreased at the end of this study. Artificial breeding during the wither season was not caused disorders on the growth, behavior and morphology. This individual breeding may lead to effective growth and development, and it will be a way to increase the survival rate when the juveniles released into the wild.

• Korean Journal of Heritage: History & Science
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• v.56 no.1
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• pp.132-140
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• 2023

In this study, a total of 21 parts of the head, carapace, and plastron of 21 tortoises were examined to investigate the characteristics of male and female sexual dimorphism of the Reeve's turtle (Mauremys reevesii), a natural monument in Korea. The ratio values of a total of 19 areas were derived from Head Length (HL) and Carapace Length (CL). As a result of comparing the ratio values, it was found that male tortoises had larger head length, head width, and head height than females compared to the size of the carapace. Since females grow eggs inside the body through internal fertilization after mating, female carapaces are judged to be larger than males overall. As a result of statistical analysis of the ratio values of the measured values, Plastron Length (PL), Bridge Length (BL), Gular Length (GL), Interhumeral Length (IH), Interanal Length (IAN), Femoral-Anal seam (FA) and Head Height (HH) showed statistically significant differences. Statistically significant in the part of the plastron, it is judged that the tortoise acts directly on each deck of the plastron as it grows. In addition, the head size of male tortoises was smaller than that of females, but it was found to be larger in proportion. It is considered that the tortoise has a rather large head compared to the body due to the male's habit of shaking his head and courtship behavior before mating. This study, we were able to identify the characteristics of sexual dimorphism in Reeve's turtle. However, since most of them were rescued, it was not possible to accurately determine habitat and age. In the future, if additional studies are conducted on individuals with clear habitats and ages, it is expected that the characteristics of the physical differences that develop as they grow can be identified.