Summit Ecosystems

Both Mauna Kea and Haleakalā are dormant volcanoes, part of the physical birth of Hawai`i from the ocean, millions of years ago. Their summits are home to unique ecosystems and rare and endangered species, many of which are found nowhere else on our planet.

The summits are themselves part of the larger ecosystem of the entire mountain and island. Each are part of a complex and uniquely Hawaiian eco-cultural system involving freshwater, land, plants, animals, ocean, and people.

There has never been a complete study of the ecosystems (e.g., hydrology, geology, vegetation) or carrying capacity of either Mauna Kea or Haleakalā. Few conservation districts anywhere in the world have been so industrialized with so little basic knowledge of the ecosystems.

Mauna Kea

The summit of Mauna Kea is situated in the ahupua`a (traditional land division) of Ka`ohe. Nearly 3,895 acres of Mauna Kea’s upper southern flank was designated as the Mauna Kea Ice Age Natural Area Reserve by the State of Hawai`i in 1981.

Deposits of two Pleistocene glacial episodes (200,000 – 130,000 years ago and 80,00 – 10,000 years ago) are found here. Some of the summit eruptions occurred during glacial times, and there is ample evidence of lava-ice and lava-water interaction. The rapid chilling of lava flows against ice is the geological explanation for the fine-grained rock prized by Hawaiians for adzes.

In addition to the glacial deposits, the summit consists of scoria cones—formed as lava was flung skyward by escaping, expanding gas, to fall back as scoria, bombs, and spatter—and lava flows. Scoria—also called cinder—is volcanic rock that contains many gas bubbles, or vesicles.

A small lake, Waiau, sits at an elevation of 13,000 feet, and its base may be a year-round layer of permafrost or an impermeable layer of fine volcanic ash.

At the summit, winds gust up to 70 miles per hour, swirling thin air with half the oxygen of sea level. In spite of nightly freezing temperatures and intense ultraviolet radiation, patches of leafy lichens and mosses dot this aeolian (influenced by the wind) ecosystem.

The alpine summit zone is inhabited full time by at least 12 cold-hardy native insects and other arthropods (invertebrates with jointed legs). They include the day-flying Agrotis moths and omnivorous cutworm caterpillars, voracious Lycosa wolf spiders, centipedes (Lithobius species) that prey on insects and their kin, and springtails (Entomobrya kea), tiny insects that jump using special spring apparatuses on their tails.

The unique, flightless wekiu bug, (Nysius wekiuicola), was discovered in 1979 on the summit cone and a few other pu`u with concentrated aerial insect fallout. Wekiu means “summit” in Hawaiian. This mini predator—about the size of a grain of rice—is dependent on fresh insects blown up the mountain from lower elevations. It hunts for prey loedged in scoria and crevices, and waits along the edges of snowmelt for tis meals. Lab studies with wekiu in controlled freezers revealed an amazing blood chemistry that kept them from freezing unil 1.4 degrees Farenheit. A sister species, Nysius a`a, which also sucks blood from insect waifs, is found only on Mauna Loa.

Construction of roads, parking lots, and facilities associated with astronomy at the summit of Mauna Kea have resulted in the loss of habitat for native summit creatures, and continues to threaten the fragile summit ecosystem. Chemicals, wastewater, and construction debris pose additional threats if not disposed of properly. Undisturbed scoria—the preferred substrate of the wekiu bug and other Mauna Kea arthropods—can be crushed by foot and vehicular traffic. Scoria cones on the summit and upper slopes, once pristine, now bear the scars of illegal, off-road, recreational vehicle use. The wekiu is a candidate for listing with critical habit designation under the Endangered Species Act.

(Text thanks to the Conservation Council for Hawai`i 2005 Wildlife Poster:  "Mauna Kea Kuahiwi Kuha'o I Ka Malie Mauna Kea.")

Haleakalā

(Information on the natural resources of Haleakalā is coming soon! Mahalo for your patience!)