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Increasing populations of large herbivores have caused environmental damage around the world, and it is necessary to improve population management strategies. Culling is a traditional management method. Antlerless deer proportions, consisting of adult female deer and fawn in Cervidae in wildlife statistics, are directly related to population increases; thus, the culling-based removal of individuals from habitats and the removal of these antlerless individuals by game hunting and nuisance control might be effective approaches for reducing population sizes. We evaluated the effectiveness of antlerless culling on 17-year density trends in the sika deer (Cervus nippon) population across an area of 1175 km2 in Fukuoka Prefecture (Japan). In 11 out of 47 grids (area measuring 5 by 5 km), the densities of sika deer tended to decline; meanwhile, in the remaining 36 grids, the densities increased. These density trends were explained by changes in the proportion of antlerless culling, as the densities declined with increasing proportions of antlerless deer. The results affirm the theory that antlerless culling is effective in population management; it is posited that antlerless-biased culling could be a crucial measure in managing overabundant populations of herbivores, contributing to more effective conservation of forest environments.

Sika deer (Cervus nippon) populations have damaged habitats, agricultural crops, and commercial forests in many parts of the world, including Asia, Europe, northern America, and New Zealand. Population management of sika deer is an important task in those areas. To better understand large-scale management and improve management efficiency, the authors estimated spatio-temporal changes of density distribution and population dynamics of a managed population of sika deer on Kyushu Island (approximately 36,750 km2), Japan. The authors estimated these changes by using fecal pellet count surveys conducted from 1995 to 2019 and results from a vector autoregressive spatio-temporal model. No decreasing trend of populations were observed at the island and prefectural scales, even though the management goal has been to reduce the population by half, and harvesting on the island increased annually until it reached about 110,000 sika deer in 2014. A possible explanation for the stable population dynamics is that the population used to determine the harvest number under the prefectural management plan was originally underestimated. This study highlights not only the difficulties of wide-area management of sika deer but also three important factors for successful management: reducing the risk of management failure, using an adaptive management approach, and appropriate management scale.

The economic loss caused by herbivore browsing in forest plantations is a concerning problem in many areas around the world. Information on the spatial distribution of browsing damage is important for forest owners when selecting locations for new plantations, because planting trees in areas of high browsing pressure increases economic losses. Although it is difficult to survey browsing damage across large areas, sporadic sampling data on browsing damage are often collected by foresters, governments, and researchers. Thus, in this study, we applied a generalized additive model (GAM) for analysis of sporadic data to reveal large-scale spatial variation in deer (Cervus nippon) browsing damage. A map of browsing pressure produced by a GAM that used years after planting (plantation age) and location as independent factors showed a few areas of high browsing pressure. In addition, browsing damage increased with increasing plantation age, and plantation stands aged 2+ years showed more browsing damage. Areas with high browsing damage estimated based on plantation stands aged 2+ years generally coincided with areas of high deer abundance, with some exceptions. Thus, this model reflects large-scale browsing damage relatively well and will help forest owners to avoid locating new plantations in areas of high browsing pressure. [ABSTRACT FROM AUTHOR]

To investigate chemical uses of Moso bamboo (Phyllostachys pubescens) shoot skin, we identified the main component of non-polar solvent extracts. To this end, a white precipitate from n-hexane extracts was evaluated using silica-gel column chromatography. The fraction with the highest recovery showed a single spot in silica-gel thin-layer chromatography (TLC) analyses. In subsequent nuclear magnetic resonance (NMR) and electron impact-mass spectrometry (EIMS) analyses, we identified the compound in the fraction as 1-triacontanol, which is a known regulator of plant growth. In addition, gas chromatography-mass spectrometry (GC-MS) experiments showed 1-triacontanol concentrations of 13.3 and 41.7 ppm in fresh and boiled skins, respectively. In boiled skins, 1- triacontanol concentrations reached a maximum of 71.3 ppm after 2 weeks of composting. Although concentrations gradually decreased thereafter, they remained at 19.7 ppm after compost maturation for 6 months. In a further experiment, seeds of Welsh onion were sown on absorbent cotton impregnated with authentic 1-triacontanol solutions, significant increase in hypocotyl length was observed. Due to the presence of 1-triacontanol, Moso bamboo shoot skin has potential as functional compost that promotes plant growth for agricultural uses. [ABSTRACT FROM AUTHOR]