Hawaii does not often experience wildfires, and life did not evolve defenses to fire. However, with the rapid acceleration of heat and drought from global warming, that has changed for the North Pacific island chain. With help from the rainforest's heavy rains, firefighters have contained the most extensive fire that burned above Mililani, Oahu. But not before 1,850 acres of irreplaceable rainforest burned.
After a major category, Hurricane Iniki barreled over Kauai in 1992, invasive species populations exploded in response.
HONOLULU (AP) — A wildfire burning in a remote Hawaii rainforest is underscoring a new reality for the normally lush island state just a few months after a devastating blaze on a neighboring island leveled an entire town and killed at least 99 people.
No one was injured and no homes burned in the latest fire, which scorched mountain ridges on Oahu, but the flames wiped out irreplaceable native forestland that’s home to nearly two dozen fragile species. And overall, the ingredients are the same as they were in Maui’s historic town of Lahaina: severe drought fueled by climate change is creating fire in Hawaii where it has almost never been before.
“It was really beautiful native forest,” said JC Watson, the manager of the Koolau Mountains Watershed Partnership, which helps take care of the land. He recalled it had uluhe fern, which often dominate Hawaii rainforests, and koa trees whose wood has traditionally been used to make canoes, surfboards and ukuleles.
Halobacteria are single-celled organisms that thrive in very salty water, like the Great Salt Lake and the Dead Sea. The bacterium is considered a so-called extremophile because of its ability to live in such an extreme environment – in this case, one where the water salinity is twice that of seawater, Fish and Wildlife noted.Hawaii has seen a generally rising trend in the amount of land that burns each year as the local climate warms. Climate change was one of several contributors to Maui’s wildfire catastrophe, and rising temperatures and associated rainfall changes are expected to increase the islands’ fire risk. These changing weather patterns will also affect Hawaii’s ecosystems and freshwater resources.
Hawaii is remarkable for its exceptionally strong gradations in the average rainfall rates over very short distances. The summit of Mt. Waialeale in central Kauai, known as one of the rainiest places on Earth, receives an average of about 450 inches of rain per year. The town of Kehaka, 15 miles to the southwest and in the rain shadow, receives less than 20 inches per year on average.
These sharp differences over short distances have made projecting future climate change in Hawaii a particularly daunting challenge.
According to a report by the New York Times, the effects of climate change have turned once-lush Hawaii into a tinderbox. The rising temperatures and declining rainfall have created dry conditions that are ideal for wildfires.
In addition, invasive species have taken over large areas of Hawaii’s forests, making them more susceptible to fires.
Climate change not only increases the risk of wildfires by driving up temperatures but also makes stronger hurricanes more likely. In turn, those storms could fuel stronger wind gusts, which can help spread fires more quickly.
Hawaii Statewide Assessment of Forest Conditions and Resource Strategy (pdf)
The Hawaiian Islands are the most isolated archipelago in the world, situated in the middle of the Pacific Ocean more than 3,200 kilometers (2,000 miles) from the nearest continent. Due to its extreme isolation and climactic conditions, Hawaii is characterized by high levels of endemism in both its native animals and plants, with over 10,000 species found nowhere else on earth. Although thousands of Hawaiian species have yet to be described, the estimated number of native species is thought to include more than 14,000 terrestrial, 100 freshwater, and 6,500 marine taxa.
For more than 70 million years, the evolution of new species vastly exceeded losses to extinction. Yet after the arrival of humans to the islands, about 700 years ago, numerous extinctions have occurred and many more species are threatened. These losses include more than half of the endemic birds, including flightless ducks, rails, and ibis, hundreds of plant species, and possibly thousands of lesser known taxa such as terrestrial insects and spiders that were lost before they were ever described. Because of this extreme isolation, relatively few species have colonized the archipelago and only a subset of these successfully establish populations over the islands’ 70 million year history. Those that did, however, found a diversity of habitat types because of elevation and climate gradients. Extremely limited or no gene flow from their distant, original populations, facilitated the rapid adaptation of colonists to their novel environments. For many such colonists, unique adaptations occurred simultaneously among populations that were isolated from one another on an island and between islands. Hawaii provides a text-book example of adaptive radiation, the process by which many new species evolved from a single common ancestor in a relatively short time span.
Although comprising less than 0.2 percent of the land area of the United States, the Hawaiian Islands hold more than 30 percent of the nation’s federally listed species, including 317 taxa of plants and animals listed by the U.S. Fish and Wildlife Service (USFWS) as endangered or threatened, 12 taxa proposed as endangered and 105 taxa as candidates for listing. Unique and varied habitats are also found across the islands. As a result, Hawaii presents both an opportunity and a challenge for conservation.