• Journal of Ecology and Environment
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• v.46 no.1
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• pp.1-7
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• 2022

Background: In this study, we proposed that the population dynamics of non-native red-eared sliders (Trachemys scripta elegans) depends on the species' habitat extension and survivorship. We used a logistic equation with time-dependent habitat carrying capacity. In detail, the present carrying capacity depends on the red-eared slider population of the previous year. Anthropogenic activities such as the abandonment of previously captive red-eared sliders or the release due to religion customs would supply new habitats to the species. Therefore we assumed that anthropogenic spread increases the habitat carrying capacity. Based on the urbanization increase rate of 3% in Korea from 1980 to 2000, we assumed an annual spread of 3% to simulate the population dynamics of the red-eared slider. In addition, the effect on the population of an increase of natural habitats due to migration was simulated. Results: The close relationship between the distributions of non-native red-eared sliders and of urbanized areas demonstrates that urbanization plays an important role in providing new habitats for released individuals. Depending on the survivorship, the population of the red-eared slider in Korea increased 1.826 to 3.577 times between 1980 and 2000. To control population growth, it is necessary to reduce carrying capacity by reducing habitat expansion through prohibition of release into the wild ecosystem and careful managements of the wetland or artificial ponds. Changes in the habitat carrying capacity showed that the population fluctuated every other year. However, after several years, it converged to a consistent value which depended on the survivorship. Further, our results showed that if red-eared sliders expand their habitat by natural migration, their population can increase to a greater number than when they have a 99% survivorship in a fixed habitat. Conclusions: Further introductions of red-eared sliders into wetlands or artificial ponds should be prohibited and managed to prevent future spread of the species. Moreover, it is important to reduce the species' survivorship by restoring disturbed ecosystems and maintaining healthy ecosystems.

• Journal of Veterinary Clinics
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• v.28 no.4
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• pp.449-451
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• 2011

An 1.28 kg, male, thirteen years of age, red-eared slider (Trachemys scripta elegans) was presented with one month history of anorexia, decreased mobility, and swelling and erythema of forelimbs. Hyperuricemia and tophaceous gout such as osteolysis at the digit, carpal and metacarpal bones with radiopaque densities around the lesion were detected. Allopurinol (20 mg/kg, PO, once a day) and u/d (Hill's diet) were selected for treatment and other antibiotics or anti-inflammatory drugs were not administered. One month after initial presentation, clinical signs and radiographic findings were improved. According to the medical response, the turtle was presumptively diagnosed as articular gout and allopurinol revealed effective response to the articular gout in turtles.

• Korean Journal of Environmental Biology
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• v.35 no.1
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• pp.57-63
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• 2017

This study was conducted to determined the status and geographical distribution of the alien invasive Red-eared slider (Trachemys scripta elegans) turtle on Jeju Island. We found thirty-two Red-eared slider habitats including twenty-five ponds, five agricultural reservoirs, a puddle and a stream. Among those, thirteen sites are newly determined habitats of the turtle. The remaining nineteen are previously reported. However, we could not find any turtles at nine sites, which were documented as turtle habitats in earlier reports. A total of one hundred thirty-three turtles were observed. Among them, we determined that thirty-nine were juvenile turtles, found in nineteen different habitats, indicating estimating that Red-eared sliders produced their progeny in the wild of this island. Because of geographical isolation by the ocean, no freshwater turtle had been found until $19^{th}$ Century. Therefore, the increased number of finding sites and Red-eared sliders indicate the possibility of human release of their pets or for other purposes, and natural propagation in the wild on Jeju Island. Our findings will be useful for management planning to deal with this invasive species, and implementation of a conservation program for native wildlife on Jeju Island.

• Animal cells and systems
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• v.4 no.2
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• pp.187-193
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• 2000

Regional distribution and relative frequency of endocrine cells in the pancreas of the red-eared slider, Trachemys scripta elegans, were investigated by immunohistochemical methods. Chromogranin (Cg) A-, serotonin-, insulin-, glucagon-, somatostatin-, bovine pancreatic polypeptide (BPP)- and human pancreatic polypeptede (HPP)-immunoreactive cells were identified in this study. Most of immunoreactive cells in the exocrine and endocrine pancreas (Langerhans islet) were generally spherical or spindle-shaped (open-typed cell), while occasionally cells round in shape (close-typed cell) were found in the basal portion or interepithelial regions of the pancreatic duct. These immunoreactive cells were located in the exocrine, endocrine pancreas and/or basal or interepithelial portion of the pancreatic duct. Serotonin-immunoreactive cells were found in the basal portion of epithelia of the pancreatic duct at a low frequency and interacinar region of the exocrine at a moderate frequency. Insulin-immunoreactive cells were found in the central portion of the endocrine pancreas, interacinar regions of the exocrine pancreas and basal portion of the epithelia of the pancreatic duct at high, moderate and low frequencies, respectively. Glucagon-immunoreactive cells were detected in the periphery of the endocrine pancreas, interacinar region of the exocrine pancreas and basal portion of the epithelia or interepithelia of the pancreatic duct at high, moderate and moderate frequencies, respectively. Somatostatin-immunoreactive cells were dispersed in the whole area of the endocrine pancreas, interacinar regions of exocrine pancreas and basal portion of the epithelia or interepithelia of the pancreatic duct at a moderate frequency. BPP- and HPP-immunoreactive cells were detected in the iinteracinar region of the exocrine pancreas at moderate and hige frequencies, respectively. However, no Cg A- and motilin-immunoreactive cells were detected in this study.

• Korean Journal of Ecology and Environment
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• v.52 no.1
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• pp.9-12
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• 2019

The red-eared slider (Trachemys scripta elegans) is the one of the most popular pets, and the most commonly traded species in the world. It is designated as an ecosystem disturbance species that has been managed in South Korea. To date, no reports of natural or anthropogenic migration and spreading of T. s. elegans in South Korea are available. In the present study, we estimated the expected route and the movable path of one female T. s. elegans found in Namsan-myun, Gyeongsan-si, Gyeongsangbuk-do. Based on the movable path, the potential destination of the female turtle was estimated to be about 282 m and 468 m away. Therefore, the moving distance of the red-eared slider to the nearest water system will be at least 606 m and at most 792 m. Our results provide the first evidence about the natural migration and spreading of exotic turtles. This study can serve as a basis for the management and countermeasures against the introduced of T. s. elegans and other exotic species in South Korea.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.247-256
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• 2000

The regional distributions and relative frequencies of endocrine cells were studied histochemically (Grimelius and Masson-Hamperl (M-H) silver methods) in the alimentary tract of the red-eared slider, Trachemys scripta elegans. Samples were taken from the esophagus, fundus, pylorus, duodenum, jejunum, ileum and large intestine. Argyrophil (Grimelius-positive) cells and argentaffin (M-H-positive) cells were found in the whole alimentary tract in this study. Spherical to spindle and/or oval to round-shaped argyrophil or argentaffin cells were located in the gastric glands of the stomach regions, in the basal portion of the epithelium of intestinal tract or the esophagus with variable frequencies. Argentaffin cells were more numerously detected in the whole alimentary tract compared with those of argyrophil cells in this study. Argyrophil cells were observed in the whole alimentary tract including the esophagus and the most predominant region was the rectum with moderate frequency. The relative frequency of these cells was rare in the esophagus, fundus, duodenum, jejunum and ileum, respectively and a few frequency in the pylorus. Argentaffin cells were also observed in the whole alimentary tract including the esophagus and the most numerously demonstrated region was the rectum with numerous frequency. They were observed with a few frequencies in the remaining regions of the alimentary tract except for the rectum, respectively. However, to know the exact type of the argyrophil cells and argentaffin cells that were observed in this study, more developmental methods such as immunohistochemistry were needed.

• Korean Journal of Environment and Ecology
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• v.33 no.6
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• pp.645-653
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• 2019

The purpose of this study was to understand the factors that affected activities and differences in seasonal activities of the invasive red-eared slider turtle (Trachemys scripta elegans) at Ansan reed wetland in Sangnok-gu, Ansan, Gyeonggi Province, the Republic of Korea. We installed nine nets in the study region to capture turtles and checked the nets twice a day for 154 days from April 28 to September 28 2013. In total, 60 individuals, including 12 juveniles, 26 adult males, and 22 adult females, were captured in 96 of 308 net checks. The multiple regression analysis of 12 environmental factors was conducted to analyze activity factors of red-eared slider turtle by assuming the number of turtles captured for a week to be the indicator of the activeness of the turtles. The result showed that the daylength was the only environmental factor that significantly affected the turtles' activity (p<0.001), and none of the other factors showed a significant correlation. The highest activity was recorded at the end of May, which was the beginning of the reproductive period. The daylength during the breeding season was significantly different from that during other seasons (Kruskal-Wallis test, p<0.001). The information about the relationship between environmental factors and species in habitat can be useful for the management of invasive alien species in the future.

• Korean Journal of Ecology and Environment
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• v.52 no.4
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• pp.378-384
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• 2019

Red-eared slider, Trachemys scripta elegans, is one of the most famous species to disturb native ecosystems in the world. In South Korea, the species was imported as pet, and now it is found whole of the country. Recent, natural breeding and spreading of the turtle has been reported. In this paper, we investigated the environmental factors to affect the reproduction of T. s. elegans. We surveyed the distribution of the turtle in Jeju island, South Korea, between 2012 to 2017. We compared the land covers and climate of habitats from breeding sites and non-breeding sites. The species was found from 38 sites in Jeju island; 21 of breeding sites and 17 of non-breeding sites. The number of total and only adult turtles was significantly higher in breeding sites than non-breeding sites (P<0.05). In breeding site, the reproduction rate from the farmland was significantly higher than others(P<0.05). However, the rate of land covers was not significant in non-breeding site (P>0.05). The difference on the climate between breeding and non-breeding was not significant(P>0.05). Moreover, none of climate factors affected to reproduction of T. s. elegans(P>0.05). Our study showed that the land covers surrounding the habitats are more important than climate for reproduction of T. s. elegans in Jeju island. This result indicates investigating the habitat and surrounding is necessary for the control of reproduction and spreading of the introduced species.

• Korean Journal of Environment and Ecology
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• v.34 no.5
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• pp.396-401
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• 2020

As the world becomes more globalized, the non-native species issue has emerged as a problem that is growing internationally. In particular, the number of non-native turtles found in the wild has been increasing sharply in South Korea. At least 15 species of non-native turtles, including the red-eared slider (Trachemys scripta elegans) first imported in the 1970s, have been found in Korea. On October 15, 2019, an alligator snapping turtle (AST, Macrochelys temminckii) was found in a stream located in Gwangju city, South Korea. The discovery of AST became a big issue in South Korea as the animal is known for its large body size and aggressiveness and was featured widely in the mass media. In this study, to learn the public's perception of non-native species, we examined comments (opinions) to the online news articles about the AST. We collected 1,100 comments from the Internet news articles on the AST. Out of the 1,100 comments, 342 (31.1%) comments were related to non-native species' issues. Most of the respondents (97.7%, n=334) stated that the non-native species are a problem. Forty two comments mentioned potential threats posed by non-native species: non-native species' aggressive nature (n=11, 26.2%) and ecological disturbance (n=31, 73.8%). Lack of responsibility (n=122, 51.7%) was the major causative factor for the introduction of non-native species, and followed by indiscriminate pet trade (n=99, 42.0%), absence of relevant legislation (n=13, 5.5%), and absence of treatment (n=2, 0.8%). Animal registration (n=59, 45.7%) was the most commonly mentioned as the way to deal with the issue of the non-native species' invasion. Our results show that the public is aware of the seriousness of the invasion of non-native species, including AST. This study highlights that researchers and government officials need to consider the public's perception and opinions. We believe that our study can serve as an essential reference for the policy direction and the management of non-native species.