Climatic and Ecological Scenarios to Guide Development of a Spatial Resist-Accept-Direct Portfolio at Nāpuʻu, Hawaiʻi
Climate change and invasive species are transforming ecosystems. The Resist-Accept-Direct (RAD) framework organizes management objectives into those that seek to Resist change and maintain historical ecological communities, those that Accept some or all aspects of ecological transformation, and those that Direct an ecological community to a preferred state. We are evaluating risks posed by climate change and invasions to inform the development of spatial RAD decisions at Nāpuʻu, a Hawaiian forest reserve that contains a rare tropical dry forest ecosystem and a suite of threatened and endangered species.
Tropical dry forests are vulnerable to transformations to invasive forest and invasive grassland. Puʻu Waʻawaʻa Forest Reserve and Puʻuanahulu Game Management Area (collectively Nāpuʻu) encompass some of the most intact remaining dry forest in Hawaiʻi and provide critical habitat for multiple endangered plant species, but are threatened by invasive plants, invasive grass-fire cycles, ungulates, and climate change. The entire North Kona region, which includes Nāpuʻu, has been projected to undergo biome shifts but there is uncertainty arising from divergent climate and biome projections.
Fencing to exclude ungulates is central to conservation in Hawaiʻi, and the project area has multiple established fenced units and additional units proposed for fencing. The State of Hawai‘i has been implementing extensive restoration and reintroduction efforts, fine fuels management, and fence maintenance in Nāpuʻu. RAD management is implemented via resistance of priority invaders within fenced areas and acceptance of invasions in unfenced areas, particularly at low elevations. Managers direct ecological change if they plant rare species at higher elevations than their known historical range, creating new plant assemblages with high concentrations of multiple rare taxa. Our project can inform outplanting strategies and prioritization of fencing of additional areas by analyzing the risks posed by climate change and invasive species and evaluating whether and where geophysical refugia may increase the durability of resistance.
Climate change and invasive species are transforming ecosystems. The Resist-Accept-Direct (RAD) framework organizes management objectives into those that seek to Resist change and maintain historical ecological communities, those that Accept some or all aspects of ecological transformation, and those that Direct an ecological community to a preferred state. We are evaluating risks posed by climate change and invasions to inform the development of spatial RAD decisions at Nāpuʻu, a Hawaiian forest reserve that contains a rare tropical dry forest ecosystem and a suite of threatened and endangered species.
Tropical dry forests are vulnerable to transformations to invasive forest and invasive grassland. Puʻu Waʻawaʻa Forest Reserve and Puʻuanahulu Game Management Area (collectively Nāpuʻu) encompass some of the most intact remaining dry forest in Hawaiʻi and provide critical habitat for multiple endangered plant species, but are threatened by invasive plants, invasive grass-fire cycles, ungulates, and climate change. The entire North Kona region, which includes Nāpuʻu, has been projected to undergo biome shifts but there is uncertainty arising from divergent climate and biome projections.
Fencing to exclude ungulates is central to conservation in Hawaiʻi, and the project area has multiple established fenced units and additional units proposed for fencing. The State of Hawai‘i has been implementing extensive restoration and reintroduction efforts, fine fuels management, and fence maintenance in Nāpuʻu. RAD management is implemented via resistance of priority invaders within fenced areas and acceptance of invasions in unfenced areas, particularly at low elevations. Managers direct ecological change if they plant rare species at higher elevations than their known historical range, creating new plant assemblages with high concentrations of multiple rare taxa. Our project can inform outplanting strategies and prioritization of fencing of additional areas by analyzing the risks posed by climate change and invasive species and evaluating whether and where geophysical refugia may increase the durability of resistance.