Earticle

To determine which external cues from females evoke the body undulation of male Hynobius leechii, a representative courtship behavior, we examined visual, tactile, and chemical cues of females and also determined whether or not direct female contacts by males were required for males to receive female chemical cues. Each male was allowed to mate with a female before and after each cue treatment for 30 min. When only visual cues of females were allowed, fewer males conducted the body undulation, and the number of body undulation significantly decreased. Despite Co2+ exposure that destroyed the mechanosensory lateral line system of male salamanders, the number of males conducting the body undulation and the number of body undulation were not significantly changed. While, when both nostrils were blocked with sponges soaked to Vaselin, significantly fewer males conducted the body undulation and the number of body undulation decreased. When we allowed only partial contacts of males to females or completely blocked the contacts, but allowed exposure to female chemical cues, the number of males conducting the body undulation significantly decreased. These findings suggest that chemical cues of females who are freely interacting with males, not partial contacts, evoke the male body undulation.

Global threats facing amphibian populations became serious. Spreading of chytridiomycosis, caused by the pathogenic fungus Batrachochytrium dendrobatidis (Bd), is one of the biggest threats of amphibians worldwide. To determine the distribution of Bd in South Korea, 819 amphibians in wild were examined for Bd by standard PCR or Nested PCR, and 57 (6.96%) positive specimens were detected. The pathogen was found in 7 native species (Bufo gargarizans, Bombina orientalis, Hyla japonica, Hynobius leechii, Rana dybowskii, Rana rugosa and Rana nigromaculata) and an exotic species (Rana catesbeiana) in South Korea. These results confirm that the amphibian chytrid fungus, Bd, is present in South Korea widely. Therefore, measures to protect Korean amphibians from chytridiomycosis and researches on the origin and pathogenicity in South Korea of the pathogen are urgently required.

In order to investigate the movement and home range of the Mongolian racerunner, Eremias argus in Taeanhaean National Park, we conducted a capture-recapture study between May 2008 to June 2009. We captured 164 individuals and recaptured 28 individuals. The moved distance of E. argus during the study period was 20.9 ± 52.1 m (male 44.8 ± 110.2 m, female 14.1 ± 12.3 m), and the home range of four lizards were estimated as 4 m2, 7 m2, 34 m2 and 84m2 (31.5 ± 37.8 m2), respectively.

The characteristics of egg sacs of Hynobius leechii in Narodo, Boseong, Jirisan, and Suwon populations and of H. yangi and H. quelpaertensis in Busan and Jeju population, respectively, were compared with each other. The results showed that the length and width of egg sacs and the length of the whiptail-like structure at the end of egg sacs were highly varied among the populations and among the different species. In special, the egg sacs of H. leechii in Narodo and Boseong populations lacked of the whiptail-like structure at the end of the egg sacs, which readily distinguished the populations from other populations. The presence and absence of the whiptail−like structure at the end of egg sacs in H. leechii might be responsible for potentially additional speciation in genus Hynobius. It is needed to be more investigated about the possibility.

To understand oviposition and egg hatching of the Mongolian racerunner (Eremias argus) in the laboratory and field, we allowed 21 female lizards to lay their eggs, collected eggs, measured mass, length, and width of the eggs, incubated the eggs, and measured mass and snout-vent length (SVL) of hatchlings. Females laid about 3 eggs per clutch over two clutches in a breeding season between late May and early July, 2010, and buried the eggs in the sand at approximately 15 – 20 cm depth. Mass, length and width of the eggs from the first and second clutches in the laboratory were not different. The relative clutch mass (total egg mass/gravid female mass) of the first clutch in the laboratory was smaller as 0.26 than 0.39 of the second clutch in the field. The incubation period of eggs in a common used incubator was shorter as 38 days than 50 days of a hand-made incubator although the former showed about 5% hatching failure. Mass and SVL of hatchlings were not different depending on the incubator types, common used and hand-made incubators, and on the first and second clutches in the laboratory.

To monitor a relocated population and a natural population of Hynobius yangi, we applied drift fences and pitfall traps which were constructed around three artificial wetlands in the relocated population and one natural wetland in the natural population and counted the number of breeding salamanders and eggs during breeding seasons from 2006 to 2010. The number of adults entering to breeding sites was the greatest around the mid March and showed a positive relationship with the amounts of daily precipitation. The number of adults appeared in the relocated population showed no significant changes, whereas the number of adults in the natural population decreased gradually mostly by habitat loss and disturbance in the areas. The operational sex ratio in both breeding populations ranged from 0.7 to 1.9. The number of adults appeared in the breeding populations showed a negative relationship with the annual minimum temperature and the monthly mean temperature and precipitation during a winter period (from November to March). Our results suggest that up to date, the relocated population has maintained its size in the areas, but need to continuously pay attention to how the disturbed natural population affects the relocated population.

In order to investigate the distribution of amphibian species in South Korea, we analyzed the survey data of the 2nd National Ecosystem Survey. As a result, we mapped the distribution of 17 amphibian species, in seven genera, six families, and two orders in South Korea and briefly described the characteristics of the distribution of each species. In this study, Karsenia koreana, a newly discovered species, was not included.

In order to evaluate the sexual morphometric size dimorphism of Scincella vandenburghi in Korea, we investigated the morphometirc characteristics of 29 male and 19 female lizards collected from 11 localities between March 2008 and April 2010 As the morphometric characteristics, we used the snout-vent length (SVL), head length (HL), head width (HW), head height (HH), axilla-groin length (AGL), forelimb length (FLL), hindlimb length (HLL) and tail length (TL) of the lizards. The morphometric characteristics between males and females were significantly different in the HL, HW, HH, AGL and FLL. In special, males had significantly larger and higher head than had females when the body length was the same, but females had larger AGL than had males. The larger head in male lizards might be associated with both intra- and inter-sexual selection and the longer AGL of female lizards might be an adaptation for increasing fecundity. The difference in sexual dimorphism between females and males of Scincella vandenburghi may increase our understanding of how the characteristics evolve and are maintained.

On 12 September 2010, an ophiophagy in Collared many−toothed snake Sibynophis chinensis from Jejusi−public cemetery garden (N 33° 25′00.1″, E 126°30′28.7″), Ora−dong, Jeju−si, Jeju Special Self−Governing Province is occurred. An ophiophagy of S. chinensis in the wild is the first record throughout the world. The swallowed snake was Asian Keelback snake Amphiesma vibakari ruthveni.