Altitudinal patterns in the population ecology of mountain bird species are useful for predicting species occurrence and behavior. Numerous hypotheses about the complex interactions among environmental factors have been proposed; however, these still remain controversial. This study aimed to identify the altitudinal patterns in breeding bird species richness or density and to test the hypotheses that climate, habitat heterogeneity (horizontal and vertical), and heterospecific attraction in a temperate forest, South Korea. We conducted a field survey of 142 plots at altitudes between 200 and 1,400 m a.s.l in the breeding season. A total of 2,771 individuals from 53 breeding bird species were recorded. Altitudinal patterns of species richness and density showed a hump-shaped pattern, indicating that the highest richness and density could be observed at moderate altitudes. Models constructed with 13 combinations of six variables demonstrated that species richness was positively correlated with vertical and horizontal habitat heterogeneity. Density was positively correlated with vertical, but not horizontal habitat heterogeneity, and negatively correlated with migratory bird ratio. No significant relationships were found between spring temperature and species richness or density. Therefore, the observed patterns in species richness support the hypothesis that habitat heterogeneity, rather than climate, is the main driver of species richness. Also, neither habitat heterogeneity nor climate hypotheses fully explains the observed patterns in density. However, vertical habitat heterogeneity does likely help explain observed patterns in density. The heterospecific attraction hypothesis did not apply to the distribution of birds along the altitudinal gradient. Appropriate management of vertical habitat heterogeneity, such as vegetation cover, should be maintained for the conservation of bird diversity in this area.

Range-size distributions are important for understanding species richness patterns and led to the development of the controversial Rapoport’s rule and Rapoport-rescue effect. This study aimed to understand the relationship between species richness and range-size distribution in relation to environmental factors. The present study tested the following: (1) altitudinal Rapoport’s rule, and a subsequent test on climatic and ambient energy hypotheses, (2) non-directional rescue effect, and a subsequent test on effect of environmental factors associated with the distribution of narrowest to widest-range species. Altitudinal species range-size distribution increased with increasing altitude and showed a negative relationship with climatic variables. These results support the altitudinal Rapoport’s rule and climatic hypothesis; however, they do not fully support the ambient energy hypothesis. Results from testing the non-directional rescue effect showed that the inflow intensity of species from both directions (high and low elevations) affected species richness. And we found that the species with intermediate range-size, rather than narrowest or widest range-size were the main cause of a mid-peak of species richness and the non-directional rescue effect. Additionally, the richness of species with intermediate range-size was highly related to minimum temperature, habitat heterogeneity, or primary productivity. Although altitudinal range-size distribution results were similar to the phenomenon of altitudinal Rapoport’s rule, the mid-peak pattern of species richness could not be explained by the underlying mechanism of Rapoport’s-rescue effect; however, the non-directional rescue effect could explain a mid-peak pattern of species richness along altitudinal gradient.

The Glandirana emeljanovi is a frog known to live in northeastern China and the Korean peninsula, but the taxonomic identity of animals from Korea is still uncertain. Here, we first determined the complete mitochondrial genome sequence of G. emeljanovi in Korea. The genome was 17,668 bp in length, consisting of 13 protein-coding genes, two rRNAs, 22 tRNAs, and a control region. The genetic analysis of available Ranidae mitogenomes supports that the genus Glandirana is monophyletic and that Korean G. emeljanovi is the same species as Chinese G. emeljanovi and is a different species from Japanese G. rugosa.

A new feather mite species, Mycterialges boycianaesp. nov. (Xolalgidae), was identified from the Oriental Stork, Ciconia boyciana Swinhoe, 1873, in Korea. Males of M. boycianaesp. nov. are distinguished from Mycterialges mesomorphus Gaud & Atyeo, 1981, in having a single triangular prodorsal shield, sinuous margins of the opisthosoma located between setae e2 and h2 on the hysteronotal shield, an oval-shaped epiandrum without posterior extensions, a shorter tibia + tarsus IV than femoragenu IV, and an absent ambulacral disc of leg IV. Females differ in having a prodorsal shield with a posterior margin that is blunt-angular, and a concave posterior margin of the hysteronotal shield with posterior extensions. This study presents the first record of the feather mite genus Mycterialges in birds of the genus Ciconia (Ciconiidae). Additionally, we determined the phylogenetic relationship among Ingrassiinae using the mitochondrial cytochrome c oxidase subunit (COI).