Hawaii, USA Photograph by John Morrison   Hawaii Tropical and Subtropical Grasslands, Savannas, and Shrublands   700 square miles (1,900 square kilometers) -- about one-third the size of Delaware Vulnerable

· Mountaintop Survivors
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern

Mountaintop Survivors

Hawaii is an island made of and by volcanoes, some of the largest being Mauna Kea, Mauna Loa, Hualalai, and Haleakala. The tops of these high volcanoes present challenging places for plants to grow and animals to live. The higher slopes of many of the volcanoes support shrubland habitats.

Special Features

If you were to climb one of these mountains, you would first reach the shrublands, where you would walk among short bushes. Climbing higher, the bushes would start to disappear and be replaced mostly by clumps of grasses. You have entered the subalpine grasslands. And if you dared to go for the highest peaks would you encounter the cold and dry conditions of alpine deserts.

	Mauna Kea is the tallest mountain in the world if measured from the sea floor.

Wild Side

Plants of this ecoregion are able to deal with dry, cold conditions and bright sunlight with adaptations such as fleshy, hairy, or silvery leaves and stalks. The beautiful 'Ahinahina silverswords found on Haleakala, Mauna Kea, and Mauna Loa volcanoes are especially known for their silvery and fuzzy appearance, as well as their spectualar flower stalks. The Haleakala hinahina, a geranium with striped white flowers, also has silvery leaves. Haleakala also has the Na'ena'e, a low shrub, with succulent leaves and orange-yellow flowers. Small, black Hylaeus bees and the pale green Blackburn's hairstreak butterfly fly quickly between the high shrubland plants in flower gathering nectar and pollinating. And the lave flow hunting wolf spider blends in perfectly with the cinders and lava of its alpine home. Different volcanic peaks support different species of high shrubland plants and animals. The endangered Hawaiian nene goose spends some of the year in high shrublands feeding on red 'Ohelo berries and other plants. During breeding season the Hawaiian dark-rumped petrel nests in burrows in the alpine cinderlands of the high volcanoes.

Cause for Concern

Main threats to this habitat include overgrazing by domestic and escaped livestock, wildfires, and trampling by hikers and other visitors. As in many other ecoregions, the introduction of species of plants and animals from other areas has been harmful to local species. For example, introduced ants kill native insects and other invertebrates, some of which are important pollinators.

For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.