In Hawai‘i, species evolved here for millions of years in isolation, completely cut off by geographic barriers. This remoteness leads to high rates of endemism, typical of islands worldwide. As the geologic barriers are broken down in today’s globalized world, new pressures place endemic species in great peril, making Hawai‘i the extinction capital of the world.
The dominant terrestrial biome of these threatened and endangered species is the forest ecosystem. Hawaiian forests are home to over 10,000 native species, 90% of which are endemic to the islands (The Nature Conservancy of Hawai’i). It also provides a wealth of ecosystem services (ie. watershed protection, nutrient cycling) that sustains all lifeforms on the islands. ‘Ōhi‘a forests are the dominant forest type on all the main Hawaiian islands. They exist in a wide range of climates, elevations, and substrates. ‘Ōhi‘a forests can be found in wet bogs of the montane and dry coastal cliffs. Historically, ‘Ōhi‘a extended from the coast all the way to the tree line (~9,000ft. in elevation). However, anthropogenic pressures and increased novel species introductions are threatening this forest system. A current pervasive threat to the ‘Ōhi‘a forests is Rapid ‘Ōhi‘a Death.
This capstone project acknowledges that invasive species are an inevitable and ongoing threat to the forest system of Hawai‘i. Novel species’ introductions are a symptom of the Anthropocene. Furthermore, from the perspective of ecological succession, they can be viewed as a disturbance in the forest system. Disturbance is a necessary component of forest systems to maintain diversity and resilience. Forest systems have the ability to adapt to and reorganize after a disturbance, however, our dependence on these systems to perform its ecosystem services into perpetuity creates systems that have lost their capacity to respond to disturbances.
This capstone poses these questions guiding design:
While returning to historical conditions is unlikely, how can stewardship of the ‘Ōhi‘a forest system increase resiliency to current and unforeseen future disturbances?
What processes integral to the functioning of the ‘Ōhi‘a forest system can be restored?
