Hawaii Invasive Species Council

In 2011 the Department of Land and Natural Resources introduced “The Rain Follows the Forest,” also known as the watershed initiative, which aims to preserve and protect Hawaii’s mauka watersheds as a source of fresh water and a home to native Hawaiian species. Much of the work planned as part of this initiative is related to preventing or controlling the impacts of invasive species. Invasive ungulates such as deer, pigs, goats, and sheep can browse native forest species and break up soil with their hooves, increasing erosion. This erosion and habitat damage results in lower water production in our mauka ecosystems, and contributes to sediment flowing downhill and entering the ocean, sometimes smothering our coral reefs. The watershed initiative also addresses the impacts of invasive plants in our watersheds. For example, invasive plants like miconia and strawberry guava have been shown to use more water than native species. The shallow roots of plants like miconia also create unstable soil layers that can contribute to erosion and even landslides. The Rain Follows the Forest describes an ambitious plan to protect our mauka forests by removing invasive plant and animal species and in some cases building protective fences that will help keep these forests intact.