The Korean water deer (WD), a predominant wildlife species in South Korea, is listed as vulnerable by the IUCN Red List. Despite belonging to the same family, Cervidae, WD show significantly fewer adult ixodid tick infestations compared to roe deer (RD). Ticks, which cannot fly, engage in questing behavior in natural environments to latch onto hosts. They detect signals like body temperature and host skin chemicals to navigate through the hair coat to the preferred epidermis. In light of this, we performed an extensive comparative study of the skin tissue and hair characteristics of both deer species, focusing on elements contributing to the reduced tick bite incidence in WD. Remarkably, WD exhibited more prominent blood vessels, sebaceous glands, and sweat glands, which are crucial for skin barrier functions (p < 0.005). Moreover, WD had irregular scale patterns on their hair cuticles and possessed hair that was significantly stiffer and 2.83 times thicker than that of RD (p < 0.001). These characteristics potentially impede ticks from reaching the epidermis hair in WD and RD in the context of tick bite prevention. Further investigations in this area could enhance our understanding of tick–host dynamics and contribute to developing preventive measures against tick-borne diseases in other deer species.
The objectives of this study were to select morphological keys for the identification of individual endangered long-tailed gorals through analysis of photographic data and to use these morphological keys to determine the number and population composition of gorals living in the Osaek Region of Seoraksan National Park. Amongst 8149 photos taken using 73 cameras in the Osaek Region, 2057 photos of faces and horns were analysed. The presence and absence of horns, shape of the horns, proportion of the ring to the length of the horn and facial colour pattern were selected as morphological keys to identify individual gorals. To verify the accuracy of the morphological keys for identifying gorals, a blind test was performed on gorals residing in the sanctuary of the Yanggu Goral Restoration Center. The test revealed that the population and age of gorals were discerned correctly by the morphological keys, but there was a 12.5% error in discriminating between sexes in gorals aged over 10 years. Fifty-six gorals were identified from 2057 pictures, based on the morphological keys and methods developed in this study. The population of 56 individuals consisted of 43 individuals aged over 2 years (subadult or adult) and 13 offspring aged less than 2 years, with a ratio of 3.3:1. Of the total 56 individuals, 45% were adults aged 10 years or older, 18% were adults aged 3–10 years, 7% were subadults aged 2–3 years, 23% were offspring aged less than 2 years and 7% were individuals aged 2 years or older, whose age and sex could not be confirmed. The sex ratio of males to females was 1.17:1, with a corrected sex ratio of 1:1 considering the 12.5% error rate for gorals aged over 10 years, amongst the 39 gorals aged over 2 years.
28 February 2011 in Korean Journal of Soil Science and Fertilizer
While urbanization leads to habitat loss for medium and large mammals, small mammals can survive in fragmented habitats. As they are known to be the primary hosts of chigger mites (Acari: Trombiculidae) that transmit scrub typhus, their habitat can be considered the primary distribution area for chigger mites. This study aims to examine the distribution of small mammals and chigger mites in four habitat types and analyzed species richness, mean intensity (MI), dominance, and infestation rate (IR). A total of six small mammal species were captured, 76.8% of which were identified as Apodemus agrarius. Species richness of small mammals was highest in forests, followed by ecotones, grasslands, and agricultural lands. Apodemus agrarius accounted for 61% of the captures in forests, 80% in ecotones, 84% in grasslands, and 50% in agricultural lands, highlighting its varying dominance across habitat types. The MI of chigger mites was higher in grasslands (215.41 ± 20.70) and ecotones (171.67 ± 30.33) and lower in forests (76.67 ± 32.11). The MI of chigger mites was higher in the fall than that in the spring, and according to the MaxEnt model, they had a narrow, dense distribution in the fall and a wide distribution in the spring. These results suggest that inducing increased species richness of small mammalian hosts by habitat management and vegetation diversification may contribute to a reduction in the MI of chigger mites.
Understanding the dietary composition of the Siberian musk deer (Moschus moschiferus) is critical for informing conservation efforts, particularly given the species’ vulnerable status in the Republic of Korea and its limited ecological data. Previous dietary studies have relied on conventional methods with limitations in taxonomic precision, hindering comprehensive insights into their feeding ecology. To address this gap, we used Next-Generation Sequencing to analyze 16 fecal samples collected in April from Gangwon Province, the habitat of M. moschiferus. Our results revealed 213 unique plant species, with Morus, Quercus, and Prunus accounting for the majority of the diet. Notably, nearly half of the identified genera, including Morus, Actinidia, and Viscum, were reported for the first time as dietary plants of M. moschiferus. This study confirms that M. moschiferus is a concentrate feeder that primarily relies on woody plants (98.8%) and may exhibit tree-climbing behavior to access parasitic shrubs like Viscum. These findings provide a foundation for future dietary analysis research and serve as valuable baseline data for the long-term conservation of M. moschiferus.
Tick-borne diseases result from human–ixodid tick encounters, making it crucial to understand host–ixodid tick interactions and host-dependent distribution for epidemiology and prevention. This study examines water deer patterns and ixodid tick interactions in designated croplands of South Korea over two years, finding that the highest deer presence occurred in July and the lowest in May, during crop harvesting. Four tick species were identified, with Haemaphysalis longicornis being predominant (92.2%). Tick life stage analysis revealed peak nymphs and adults in July and larvae in October. Nymph abundance correlated positively with nearby water deer. MaxEnt biodiversity prediction results indicated wider water deer distribution in summer, reflecting their tendency to use multiple croplands. Areas with nymphs and adults aligned with predicted deer presence in summer, while larval areas aligned in autumn. Increased agroforestry expanded water deer habitats, enhancing tick dispersion. Prevention involved minimizing human–deer encounters by strategic land use in tick-prone areas. This comprehensive study provides insights into preventing severe fever with thrombocytopenia syndrome in agricultural workers, emphasizing the need for targeted interventions based on host behavior and tick life stages in different seasons.