Woo-Shin Lee

Characteristics of hazel grouse Bonasa bonasia distribution in southern Korea

During October 1998 - May 1999, we studied the distribution of hazel grouse Bonasa bonasia and the structure of their habitats in southern Korea. Hazel grouse were censused from the responses to calls imitated using a Scandinavian metal hunters whistle in winter and spring along line transects. Hazel grouse were distributed in most of the high mountain forest areas in southern Korea. The frequency of occurrence varied with altitude within the range of 300–1,200 m a.s.l., with the highest density at 600–900 m a.s.l. Altitudinal distribution differed between seasons, however, and hazel grouse were observed at lower altitudes more often in winter than in spring. They occurred in mixed, deciduous and coniferous forest areas, but the use of forest types varied by season. Particularly many individuals were observed in planted Japanese larch Larix leptolepis forests. The coverage and density of understory vegetation was more developed where hazel grouse were observed, but coverage more than 2 m above ground did not seem to be important in explaining hazel grouse presence. The occurrence of hazel grouse was related to the development of understory vegetation more than to forest type. Seasonal use of forest types may have been related to the combined availability of food and cover in understory vegetation.

Measuring the Behaviors of Wintering Black-faced Spoonbills (Platalea minor ): Comparison of Behavioral Sampling Techniques

Abstract We recorded the diurnal behaviors of the endangered Black-faced Spoonbill (Platalea minor) for 16 days during the wintering season in Jeju Province, Korea to find an appropriate and effective sampling technique for behavioral study. Two main techniques were used and compared: focal sampling with continuous recording and scan sampling with instantaneous recording at various time intervals. As a result, recording the behavior of a focal bird for more than 20 min per h was the best technique with high accuracy and precision. However, to select less time- and labor-intensive techniques we concluded that scan samplings with less than 10 min intervals or focal samplings with more than 15 min durations are appropriate measurements of the spoonbill’s behaviors. Considering sampling sizes, scan sampling with 5 min recording intervals can be an effective technique but additional methods are also required to obtain significant information for infrequent or occasional behaviors. We suggest that each sampling technique should be validated by preliminary or supplementary surveys to estimate the endangered animal’s behaviors and this can be an important part of the groundwork for conservational efforts on the Black-faced Spoonbill.

Influence of forest fragmentation on the winter abundance of mammals in Mt. Chirisan National Park, South Korea

Abstract We examined the influence of both local habitat and landscape variables on mammal species abundance in a forest fragmented by road construction and in continuous forest in 8 study sites in Mt. Chirisan National Park, South Korea, from 2001 to 2004. We recorded tracks of 8 species of mammals, Siberian weasels (Mustela sibirica), yellow-throated martens (Martes flavigula), Bengal cats (Felis bengalensis), wild boars (Sus scrofa), water deer (Hydropotes inermis), roe deer (Capreolus capreolus), Korean hares (Lepus coreanus), and red squirrels (Sciurus vulgaris), on the snow on 8 2-km transects in our study areas. There were significant differences in density of snags, mean tree basal area, and in shrub coverage between the fragmented and unfragmented forest areas. We found significant differences in abundance index of tracks between the fragmented and unfragmented areas for 5 mammal species; the others had even distributions. Of the 8 mammal species analyzed, 5 species related to landscape and local vegetation variables in a stepwise approach with repeated measures. Landscape variables are significant predictors of abundance for many mammal species. Forest managers should consider multiple measures of forest fragmentation sensitivity when making forest management decisions.

Seasonal changes in territorial behaviour of hazel grouse (Bonasa bonasia) in a temperate forest of South Korea

We studied the seasonal changes in territorial behaviour of hazel grouse (Bonasa bonasia) from December 1999 to July 2001 in a temperate forest of South Korea. The study was based on the use of radio telemetry. Territory size and degree of overlap increased after the breeding period, and index of advertisement and border disputes decreased. In spring, the territory was defended by both males and females. During autumn and winter, this behaviour was relaxed to such a degree that hazel grouse cannot be considered territorial, but as forming a home range.

Altitudinal Variation in Parental Provisioning of Nestling Varied Tits (Poecile varius)

Abstract We recorded parental provisioning rates of Varied Tits (Poecile various) at different altitudes (n  =  17, 7, and 11 nest boxes at 300, 900, and 1,400 m, respectively) to examine if males and females cooperate in response to increased provisioning pressure due to nutritional demands of nestlings. Females provisioned nestlings more than males irrespective of altitude. Provisioning rates of males and females tended to increase with elevation, but the increase was greater for males. Provisioning was low early in the nestling period, and gradually increased reaching a peak between 9 and 10 days after hatching. The provisioning rate of females at the peak provisioning period (8–10 days) did not increase markedly at any altitude. Provisioning by males during the peak period increased and they contributed more during this period than at other times. The provisioning rate of males increased linearly with elevation. The provisioning rate of female Varied Tits also increased with elevation, but the increment ratio was lower than that of males. Changes in provisioning rates with elevation may be due to the need to invest more in parental care under unfavorable environmental conditions. Parents at high altitudes experience more difficulty provisioning, not only because of nestling growth, but also because provisioning is required more often. Thus, increased provisioning by males, which have a lower provisioning frequency relative to females, may be an investment to reduce foraging pressure on females and to ensure survival of nestlings.

A new aphid genus Neoaulacorthum (Hemiptera: Aphididae: Macrosiphini), determined by molecular and morphometric analyses

We performed molecular and morphological analyses to determine the generic limit of the genus Aulacorthum, including several species with controversial taxonomic histories. The sequences of four mitochondrial genes, COI, COII, srRNA and lrRNA, and one nuclear gene, EF1a, implied that Aulacorthum is not monophyletic, with Aulacorthum magnoliae and Aulacorthum nipponicum forming a clade that is not sister to other currently recognized Aulacorthum species. Morphometric analysis based on 20 morphological characters also showed that A. magnoliae and A. nipponicum exhibited morphological characteristics distinct from congeneric species. Based on these results, we propose a new genus, Neoaulacorthum ge. n., for A. magnoliae and A. nipponicum.

A cryptic species of Aphis gossypii (Hemiptera: Aphididae) complex revealed by genetic divergence and different host plant association.

Three cryptic species, Aphis gossypii, Aphis glycines, and Aphis rhamnicola sp. nov., are recognized as sharing buckthorn plant, Rhamnus spp. as primary hosts. These aphid species have morphological similarities; however, there are significant genetic differences between the three cryptic species. Based on the high level of genetic divergence and the different secondary host association, we described a new species, Aphis rhamnicola sp. nov., for apterous and alate vivipara, fundatrix, ovipara, and gynopara, including diagnostic key for the host sharing species in the genus Aphis.

Differences in Small-Mammal and Stand Structures between Unburned and Burned Pine Stands Subjected to Two Different Post-Fire Silvicultural Management Practices

We examined the abundances of three small-mammal species, Korean field mice (Apodemus peninsulae), Korean red-backed voles (Myodes regulus), and striped field mice (A. agrarius), and a stand structure of unburned and burned stands resulting from two different post-fire silvicultural management practices within a pine forest in South Korea. The habitat structure changed dramatically depending on the post-fire silvicultural practices. Most measured variables of the stand structure and downed trees were significantly different among the differently-managed stands. We captured 776 animals of five species (1114 captures in total) in nine stands, each trapped during the two-year study period. The total abundances of captured small mammals did not differ significantly among the differently-managed stands. Mean Jolly—Seber estimates of the population density of M. regulus were 79%–291% higher in the post-burned untreated stand, whereas those of A. agrarius were 214%–491% higher in the post-burned Japanese red pine (Pinus densiflora) planted stand. The preferred stands for small mammal species were generated by forest fire and post-fire silvicultural practices. The values of understory vegetation, coarse woody debris, and downed trees were most strongly related to small-mammal abundance following post-fire silvicultural practices. Therefore, the effects of post-fire silvicultural practices on small-mammal populations should be considered in the post-fire management of a burned pine forest.

Influence of roads on small rodents population in fragmented forest areas, South Korea

The road effect on small rodent population is investigated at 8 fragmented forest areas in the Baekdudaegan mountain range, South Korea in September 2001. We especially focused on the distribution and body condition of small rodents near the roads. Korean field mouse (Apodemus peninsulae) seems to be more sensitive to the existence of a road than striped field mouse (Apodemus agrarius). Korean field mouse prefers interior forest area to around road. Striped field mouse is a habitat generalist and has wide distributional range around road, but Korean field mouse is forest-inhabiting species and their distribution is limited in forest area. These results suggest the effect of road is different on each small rodent species and their habitat preferences.

Improvement of TERCOM aided inertial navigation system by velocity correction

TERCOM is a terrain referenced navigation system using batch processing method which determines vehicles current position by comparing a series of terrain height measurements with database. Generally, it is known that TERCOM operates well over terrain with high roughness. However, if the attitude and velocity error of INS is not corrected, the navigation solution of conventional TERCOM aided INS can diverge. This paper describes the TERCOM aided INS algorithm and show the divergence problem. To solve the problem, we propose an improved TERCOM aided INS algorithm which corrects the velocity error of INS using linear Kalman filter, even though the navigation system does not have a speedometer. It is shown that the proposed TERCOM algorithm can prevent divergence of navigation solution based on computer simulations.