Increased urinary creatinine during hibernation and day roosting in the Eastern bent-winged bat (Miniopterus fuliginosus) in Korea.

Torpor and arousal cycles, both daily and seasonal (e.g. hibernation), are crucial for small mammals, including bats, to maintain the energy and water balance. The alternation between torpor and arousal leads to metabolic changes, leaving traceable evidence of metabolic wastes in urine. In this study we investigated urinary creatinine and acetoacetate (a ketone body) in the Eastern bent-wing bat (Miniopterus fuliginosus) in Mungyeong, South Korea. We found an increase in urinary creatinine during torpor in summer, indicating changes in renal water reabsorption rates during the active season. Although we could not confirm ketonuria in hibernating bats due to a methodological limitation caused by the small amount of urine, we verified an increase in urinary creatinine concentration during hibernation. This finding suggests that managing water stress resulting from evaporative water loss is one of key reasons for arousal during hibernation in Eastern bent-wing bats.

Home Range and Habitat Use of the Swan Goose (Anser cygnoides L. 1758) during Wintering in the Seocheon Tidal Flat, South Korea, Using GPS-Based Telemetry.

The Seocheon Tidal Flat is an important staging and wintering site for the Far East Russian population of Swan Goose (Anser cygnoides) in the East Asian-Australasian Flyway. However, rapid environmental changes for tourism in this area can threaten the survival of this vulnerable population by hindering sufficient rest and wintering; therefore, establishing protection strategies based on Swan Goose behavioral characteristics is necessary. Here, we estimated Swan Goose core home ranges and habitat use based on GPS tracking data collected at the Seocheon Tidal Flat in South Korea from 2017-2018. The home range of Swan Geese was estimated to be an area from Yubu Island in the south to Janggu Bay in the north; however, the core home range and habitat use characteristics differed significantly between daytime and nighttime (Day: 59.9 km2, Night: 40.3 km2, on average, 100% MCP). During the day (08:00-18:00), Swan Geese mostly spent time resting or feeding on tidal flats, especially those around tidal channels or paddy fields near Janggu Bay, whereas they mostly rested on sand dunes near Yubu Island along with the mudflats at Janggu Bay at night. Our results provide practical information on the habitat use of wintering Swan Geese population over time and indicate that Yubu Island is an important resting place. Hence, these results can contribute to evaluating threats to Swan Geese and establishing management and protection strategies for the Seocheon Tidal Flat, a major wintering site for the Far East Russian population of Swan Geese.

Urinary creatinine varies with microenvironment and sex in hibernating Greater Horseshoe bats (Rhinolophus ferrumequinum) in Korea.

BACKGROUND: In temperate regions many small mammals including bats hibernate during winter. During hibernation these small mammals occasionally wake up (arouse) to restore electrolyte and water balance. However, field data on water stress and concentration of bodily fluids during hibernation is scarce. Urinary creatinine concentration has long been used to calibrate urinary hormone concentration due to its close correlation with urine concentration. Therefore, by investigating urinary creatinine concentration, we can estimate bodily fluid concentration. In this study, we investigated changes in urinary creatinine from greater horseshoe bats (Rhinolophus ferrumequinum) hibernating in abandoned mineshafts in two regions in South Korea. RESULTS: We collected 74 urine samples from hibernating greater horseshoe bats from 2018 to 2019. We found that urinary creatinine concentration was higher in February and March and then declined in April. There were also indications of a sex difference in the pattern of change in creatinine concentration over the three months. Bats in the warmer and less humid mineshaft had higher urinary creatinine concentrations than bats in the colder and more humid mineshaft. CONCLUSIONS: These results indicate that hibernating bats face water stress as urinary concentration increases during winter and that water stress may vary depending on the microenvironment. Sex differences in behaviour during hibernation may influence arousal frequency and result in sex differences in changes in urinary creatinine concentration as hibernation progresses. Although further behavioural and endocrinal investigations are needed, our study suggests that urinary creatinine concentration can be used as a proxy to estimate the hydration status of bats and the effect of sex and environmental factors on arousal patterns during hibernation.

The complete mitochondrial genome of the millipede Epanerchodus koreanus Verhoeff, 1937 collected in limestone cave of Korea (Polydesmidae: Polydesmida).

We have determined the second mitochondrial genome of Epanerchodus koreanus Verhoeff, 1937 collected in limestone cave of Korea. The circular mitochondrial genome of E. koreanus is 15,581 bp long. It includes 13 protein-coding genes, two ribosomal RNA genes, and 22 transfer RNA genes. Its gene order was different from the rest three Polydesmida mitochondrial genomes, resulted from relocation of tRNAs, rRNAs, and ND1. The base composition was AT-biased (75.1%). Phylogenetic trees displayed phylogenetic relationship, which is congruent to previous study, except Sphaerotheriidae sp. clustering with Helminthomorpha.

Applicability of propidium monoazide (PMA) for discrimination between living and dead phytoplankton cells.

Propidium monoazide (PMA) is a highly selective dye that penetrates only membrane-compromised, dead microbial cells and inhibits both DNA extraction and amplification. PMA has been widely used for discrimination between living and dead microbial cells; however, the application of PMA in phytoplankton studies has been limited. In this study, we attempted to evaluate its applicability for the discrimination of viable phytoplankton. We tested PMA on seven phytoplankton species, Microcystis aeruginosa, Anabaena sp., Aphanizomenon sp., Synechocystis sp., Cryptomonas ovata, Scenedesmus obliquus, and Nitzschia apiculata as representatives of the major phytoplankton taxa Cyanobacteria (first four species), Chlorophyta, Cryptophyta, and Bacillariophyta, respectively. Our results showed that application of PMA to phytoplankton living in freshwater has the potential to distinguish viable from dead cells as in microbial studies. Particularly, PMA differentiated viable from dead cells in cyanobacterial species rather than in other phytoplankton taxa under our experimental conditions. However, our results also showed that it may be necessary to adjust various conditions affecting PMA treatment efficiency to expand its applicability to other phytoplankton. Although all factors contributing to the effects of PMA could not be evaluated, our study showed the applicability of PMA-based molecular approaches, which can be convenient quantitative methods for distinguishing living from dead phytoplankton in freshwater ecosystems. Setting optimal treatment conditions for other phytoplankton species may increase the efficacy of PMA-based molecular approaches.

Complete mitochondrial genome of Haematopus ostralegus (Charadriiformes: Haematopodidae).

The Eurasian oystercatcher (Haematopus ostralegus), Near Threatened in the IUCN red list, was designated classified endangered species II by the Ministry of Environment of Korea and a Natural Monument (No. 326) by the Cultural Heritage Administration of Korea. In this study, the complete mitochondrial genome (16,798 bp) of H. ostralegus was determined for the first time, including 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and 1 non-coding region. The overall base composition was A (31.4%), C (31.3%), G (13.8%), and T (23.5%), so the percentage of A and T (54.9%) was slightly higher than that of G and C. A phylogenetic analysis using concatenated mitogenomes revealed that the family Haematopodidae has a closer relationship with the family Recurvirostridae and H. ostralegus and H. ater clustered together. The results are expected to provide useful resources for species identification and further phylogenetic studies of genus Haematopus.

Sequencing and analyzing complete mitochondrial genome of Anser cygnoides (Anserini: Anserinae).

The complete mitogenome sequence of Anser cygnoides was determined and compared with those previously released. The whole mitogenome was 16,740 bp, with 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 putative non-coding region (1178 bp). The overall nucleotide composition was 30.2%, 32.0%, 15.1%, and 22.7% for A, C, G, and T, respectively. Phylogenetic analyses strongly supported two clades in Anserini and demonstrated that A. cygnoides is not monophylogenetic. This division of A. cygnoides indicates that more research is necessary to clarify phylogenetic relationships for A. cygnoides and determine how they relate to morphological traits.

Use of length heterogeneity polymerase chain reaction (LH-PCR) as non-invasive approach for dietary analysis of Svalbard reindeer, Rangifer tarandus platyrhynchus.

To efficiently investigate the forage preference of Svalbard reindeer (Rangifer tarandus platyrhynchus), we applied length-heterogeneity polymerase chain reaction (LH-PCR) based on length differences of internal transcribed spacer (ITS) regions of ribosomal RNA (rRNA) to fecal samples from R. tarandus platyrhynchus. A length-heterogeneity (LH) database was constructed using both collected potential food sources of Svalbard reindeer and fecal samples, followed by PCR, cloning and sequencing. In total, eighteen fecal samples were collected between 2011 and 2012 from 2 geographic regions and 15 samples were successfully amplified by PCR. The LH-PCR analysis detected abundant peaks, 18.6 peaks on an average per sample, ranging from 100 to 500 bp in size and showing distinct patterns associated with both regions and years of sample collection. Principal component analysis (PCA) resulted in clustering of 15 fecal samples into 3 groups by the year of collection and region with a statistically significant difference at 99.9% level. The first 2 principal components (PCs) explained 71.1% of the total variation among the samples. Through comparison with LH database and identification by cloning and sequencing, lichens (Stereocaulon sp. and Ochrolechia sp.) and plant species (Salix polaris and Saxifraga oppositifolia) were detected as the food sources that contributed most to the Svalbard reindeer diet. Our results suggest that the use of LH-PCR analysis would be a non-invasive and efficient monitoring tool for characterizing the foraging strategy of Svalbard reindeer. Additionally, combining sequence information would increase its resolving power in identification of foraged diet components.

Monitoring of phytoplankton community structure using terminal restriction fragment length polymorphism (T-RFLP).

To establish molecular monitoring for the phytoplankton community in aquatic ecosystems, we analysed the terminal restriction fragment length polymorphism (T-RFLP) of small subunit ribosomal RNA gene (18S rDNA) sequences of nuclear genomes from the algal strains of culture collections and environmental samples of two freshwater reservoirs (Sangcheon reservoir and Seoho reservoir, Korea). Terminal restriction fragment (T-RF) length database was also constructed from twelve strains of algal culture collections to annotate and identify the phytoplankton species from T-RFLP profiles. Algal species in reservoirs were identified and monitored through the colony sequencing and T-RF length patterns of 18S rRNA. In this study, 41 unique clones were identified from two reservoirs including Chlorophyta, Cryptophyta, and Alveolata. In the case of Cryptomonas sp., we found significant linear relationships between T-RF peak areas and biovolumes by cell counting. Our results suggest that T-RFLP analysis can be a fast and quantitative monitoring tool for species changes in phytoplankton communities.