Conservation Priorities

Forested Watersheds

Hawaii's native ecosystems once extended from the mountains to the sea. Today, the vast majority of Hawaii's native plants and animals find refuge in the upland forests, in large native landscapes scattered throughout the islands.

The Islands' native forests are among the world's biological treasures, sheltering more than 10,000 native species –  more than 90% of which are endemic or unique to these islands.

Hawai'i has almost as many types of native forest as there are U.S. states, including the nation's only tropical rain forests. ‘Ōhi'a lehua and koa are the dominant forest types but all total, there are 48 different native Hawaiian forest and woodland types and more than 175 different species of native trees, the vast majority of which are found nowhere else in the world.

But today, for all their biological richness, these forests are among the most endangered in the world. Hawai'i has already lost half of its natural forest cover. Currently, more than one-third of the plants and birds on the U.S. Endangered Species List are from Hawai'i. When spiders, snails, and insects are included, nearly 60% of Hawaii's total native flora and fauna is endangered, by far the highest percentage of any state.

Destruction and the loss of forest habitat are the primary causes of species decline.

What's at Stake

Propelled by a sense of urgency, the Conservancy has stepped up our efforts to save these last stands of vanishing Hawaiian forest and the native plants and animals who depend on these habitats to survive.

People also depend on native forests for survival. Forested lands are our islands’ primary watersheds, supplying us with hundreds of billions of gallons of fresh water each year. Our forests protect our reefs and beaches from destructive run-off and sediment, clean and cool our air, and are our best defense against flood and drought.

The Hawaiian forest also shelters thousands of native species vital to the survival of Hawaiian cultural practices. The native forest provided a foundation for the Hawaiian culture, and the uplands were held sacred as wao akua, the realm of the gods, set aside from wao kanaka, the realm of the people.

Critical Threats

Hawaii’s native forests are the result of millions of years of evolution, yet since the onset of human arrival 1,500 years ago, their history has largely been one of loss and destruction.

While the historical impacts from agriculture, grazing, logging, and development are responsible for much of this loss, the greater threat today is the destruction wrought by invasive plants and animals.

Impacts by humans, including the introduction of feral cattle, pigs, goats, rats, weeds, insects, and other invasive species, has rendered the islands’ native forests among the most endangered in the world.

Invasive species prey upon and destroy the habitat of native species, compete with them for food and habitat, and spread diseases. Over time, they transform the forests they invade, changing them from native to non-native, simplifying their structure, altering soil composition, increasing the risk of fire, and endangering our future water supply. 

What the Conservancy is Doing

The Conservancy is working with local communities and our conservation partners throughout the islands to protect our precious forested watersheds. Our strategic approach is focused on:  

Safeguarding rich reservoirs of biodiversity statewide: managing the Conservancy's 10 preserves, which provide essential habitat for rare and endangered native plants and animals;

Building watershed partnerships: collaborating with other landowners to protect nearly 1.5 million acres of forested lands and the larger ecosystems of which our preserves are a part;
Strengthening forest protection: advancing new methods to control invasive animal and weed populations, to contain and reduce their destructive impacts on native forests.



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