Since its initial designation as an Urban Natural Park in 1971, Umeon-mountain has been recognized as a Natural Ecological Park in 2004 and a Wildlife Protected Area in 2007, specifically for the conservation of the toad habitat. However, following a significant landslide in 2011, extensive flood control construction altered the habitat conditions, and toads have not been observed since 2008. In response, a habitat restoration project was initiated in 2017 to improve the environment for toad populations.
In the 2024 seasonal survey, 284 plant species across 85 families were recorded, including the endangered Cicuta virosa near the reservoir, underscoring the need for habitat protection. The expansion of ornamental plantings since 2018 has resulted in a decline of native oak woodlands, impacting local fauna. The proliferation of invasive species, such as American pokeweed and ragweed, has disrupted ecological health, indicating an urgent need for invasive species management.
The endangered narrow-mouthed toad has shown stable population levels since 2019, and Seoul-protected species, including tree frogs and bullfrogs, inhabit the reservoir and wetlands, enhancing the area’s conservation value. While toads were last observed laying eggs in 2005, subsequent surveys, including eDNA analysis, have not detected their presence. This highlights the need for targeted ecological improvements for both reservoir and wetland habitats to support these species.
Bird surveys identified 22 families, 31 species, and up to 199 individual birds, including protected species such as the Northern boobook and woodpeckers. Despite the reservoir’s presence, waterbird diversity remains low, with a lack of prey insects impacting predatory species, indicating further habitat enhancement is needed. Despite these challenges, the habitat remains significant for indigenous species, like the Amur goby, underscoring its potential to evolve into a robust habitat through additional conservation efforts.
While Umeonsan plays a critical role as a refuge for diverse wildlife, several environmental and management factors pose challenges to ecological integrity. The expansion of trails and viewing decks, coupled with water extraction and wetland fragmentation, has negatively impacted amphibian and reptile habitats, disrupting critical species such as the toad. High visitor usage and unsupervised collecting during breeding seasons also present direct threats to species survival.
To protect habitats for the toad, narrow-mouthed toad, and Cowbane, various conservation measures, such as habitat restoration, water quality and quantity management, and invasive species control, are essential. Native vegetation restoration is necessary to maintain ecological balance, alongside measures to safeguard water resources and sediment control. A comprehensive management framework, including water environment, vegetation, fauna, and facility maintenance, should be implemented. Regular ecological monitoring will assess conservation effectiveness, with adjustments to management plans as required. Educational programs should raise public awareness of the area’s ecological importance and engage visitors effectively in conservation.
Furthermore, it is recommended to expand the designated protection areas beyond current breeding sites to include aquatic ecosystems, encompassing the broader habitats of toads and Rana huanrensis. Expanding small-scale biological habitats and buffer zones along 30-50m of the water system, with protection from upper catchments and surrounding forests, is also advisable to enhance amphibian conservation in Umeonsan.