# Global Climate Change Impacts on Plants of Hawai‘i Volcanoes National Park

## Science Center Objects

Climate change is expected to alter the seasonal and annual patterns of rainfall and temperature in the Hawaiian Islands. Warming temperatures and altered precipitation patterns both impact ecological systems, but managing these impacts is difficult without detailed information on the magnitude and timing of these climate-related changes.

Hapu‘u fronds. Photo: J. Jacobi

Pukiawe in bloom. Photo: J. Jacobi

Overview:

Climate change is expected to alter the seasonal and annual patterns of rainfall and temperature in the Hawaiian Islands. Warming temperatures and altered precipitation patterns both impact ecological systems, but managing these impacts is difficult without detailed information on the magnitude and timing of these climate-related changes. Resource managers at Hawaii Volcanoes National Park (HAVO) require information on how climate change may shift plant distributions and those variables that control plant growth and fitness. Of particular concern to managers is whether species associated with mesic vegetation types will be able to migrate across the HAVO landscape, or rather will the system collapse as a result of drying, warming, and fire before species can successfully migrate to more suitable sites. Current management within HAVO is focused in Special Ecological Areas (SEAs), which are roughly configured to protect representative habitat types by controlling the most incipient invasive plant species (Loh et al. in prep.) Species migration rates and directions across HAVO need to be estimated and synthesized into discrete products to better permit SEAs to be configured and managed to provide maximum protection for important species including federally listed and cultural keystone species.

Project Objectives:

This project will combine recent climate modeling over the state of Hawaii with existing models of plant species range to forecast suitable habitat ranges in the future. We will produce a probabilistic surface of acceptable habitat for thirty-eight species, both native and non-native, that have been identified as being of management interest. These estimates will be at two targets in the future – 2040 and 2070, as well as interpolating three different trajectories that climate change may follow between the present and future climate.

‘Ohelo berries. Photo: J. Jacobi

1. Combine the IPRC climate projections and Price et al. (2012) plant distribution models to produce maps of future plant species ranges. Projections at intermediate time periods (ca. 2040, 2070) will be done by interpolating between models of near present-day and end-of-century. Inter-annual variation in the modeled periods and the non-linear response of vegetation range models will be used to generate a probabilistic surface of future species ranges.
2. Assess the effectiveness of the current location of Special Ecological Areas (SEAs) in Hawaii Volcanoes National Park to protect natural resources, specifically mesic biomes and federally listed species found therein, in anticipation of likely future conditions driven by climatic changes at intermediate and end-of-century time periods (ca. 2040, 2070 and 2100).

Highlights and Key Findings:

Most of the HAVO SEAs were projected to lose a majority of the modeled native species and all but one alien species; this trend occurred in most SEAs including those at low, middle and high elevations. There was good congruence in the current distribution of species richness and SEA configuration; however, over time the projected species-rich hotspots increasingly occurred outside of current SEA boundaries. Our forecasted shifts in suitable habitat for native plant species will assist park managers in assessing configuration of and prioritizing future work in SEAs. Potential changes to SEAs could include altering boundaries of existing SEAs, establishing new ones, or expanding existing SEAs to incorporate future diversity hotspots in areas not currently managed by park staff. Moreover, our results will assist HAVO managers working with adjoining land owners and partner agencies to prioritize conservation efforts island-wide.

Project reports and data are available through the Pacific Islands Climate Science Center.

This project is complete.

A final report and journal publication are available.