Publications by authors named "Nam-Yong Ra"

To study the function of arginine vasotocin (AVT) in a specific courtship behavior (body undulation) in male Hynobius leechii, we injected various doses of AVT or an AVT V1a or V2 receptor antagonist into breeding and non-breeding males. After these injections, we placed the males alone or with breeding females in Petri dishes and measured the incidence and frequency of body undulation. Additionally, to test whether AVT modulates the olfactory response of males, we exposed breeding males that were injected with AVT to female odors and measured the same response.

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We used field surveys and statistical models to investigate habitat associations of the endangered gold-spotted pond frog (Rana chosenica). The characteristics of its habitat are of great importance for effective conservation for this declining species in western South Korea. We evaluated a priori models that incorporated biotic and abiotic variables at the pond and landscape scales.

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Because of their complex life styles, amphibians and reptiles living in wetlands require both aquatic and terrestrial buffer zones in their protected conservation areas. Due to steep declines in wild populations, the gold-spotted pond frog (Rana chosenica) is listed as vulnerable by the IUCN. However, lack of data about its movements and use of habitat prevents effective conservation planning.

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In recent years, there has been a rapid decrease in amphibian populations worldwide, and infectious diseases have been associated with this decline. Diseased frogs inhabiting Korea were collected from fields, and the diseases were identified by morphological and molecular analyses. Two fungal diseases-saprolegniasis and chromomycosis-were detected in the frogs.

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