Environmental characteristics of subalpine ponds and their use by animals in a massive landslide area of the Northern Japanese Alps

Ponds and wetlands often develop in landslide areas; however, their environmental characteristics and ecological roles remain underexplored. This study examined ponds withi n a massive landslide area in the northern part of the Northern Japanese Alps, investigating their environmental attributes and animal usage. Water analysis showed that ponds differ markedly from streams in the landslide area in terms of water quality and temperature, besides the distinction of being lentic or lotic systems. In addition, the ponds themselves were categorized into two groups in terms of water quality. This diversity in water environments may enhance the site's biodiversity, warranting further investigation. Sika deer Cervus nippon were the most frequently observed species, engaging in behaviors such as drinking water and consuming aquatic plants. Wild boar Sus scrofa were also observed wallowing in mud along the pond edges. These findings suggest that the ponds serve as valuable habitats for mammals in this landslide area.