Hawaii
Ecology
A combination of factors controls Hawaii's environment. The islands are close to the Equator -- Hawai'i is further south than Egypt -- and lonely. From Honolulu, it is 2.000 miles to the nearest large land mass. That is more isolated than any other spot on earth.
And, there is the weather...
the Trade Winds -- steady winds from the northeast nearly all the time -- have shaped this tree, but why is the land so dry?
Mountains
High islands have mountains thousands of meters tall that rob moisture from the sea breeze. As ocean breezes lift over the mountains, the rise cools the air, forms clouds and drops the moisture as heavy coastal rain. When the winds descend on the far side of the mountains, they are dry...
This view from about 8000'/2600m shows the clouds reaching up the side of Mauna Kea
The extended mountain of Mauna Kea makes up most of the central part of Hawai'i island.
Heating of the summit causes an inversion layer which traps ocean air between the mountains and the sea. Clouds typically form at about 8,000 feet or less, while the mountains rise above 10,000 feet.
Below the clouds, the land on the northeast coast is green and wet. Above the cloud level, and on the western and southern coasts, the land is dry.
View from the summit at 13,796'/ 4400m looking down at cloud cover above the northeast side of the island.
Rainforest, Windward Coast of Hawaii Island
Exotic blossoms and the rainforest can flourish when ocean winds come ashore to rain on the eastern flank of the islands.
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forest streams are the result of the frequent rainfall |
Numerous waterfalls rush down the steep coastal terrain |
Lush rainforest growth is part native and part alien, introduced plants |
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Gorgeous flowers at Hilo market reflect the wonderful climate |
Hawai'i's plants are a mixture of curious native plants and alien invaders brought from around the world. Hawaii is so far from other land that it had a relatively small set of plants and animals before humans arrived. |
Banyan, bamboo and plants from around the world grow in profusion in the year round warmth and regular rain |
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Waipio is famous for the spectacular falls which drop over its 2000' cliffs into the valley |
Laupahoehoe on the Hamakua Coast of Northeastern Hawai'i |
Spectacular Akaka Falls exists because of the rain that falls in the hills above the Hamakua coast |
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Ferns & banana
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The origin of this square cutout in the lava bed of this Akaka Park stream is unknown -- but it looks suspiciously like a hot-tub to me! |
Bamboo |
Western Coast of Hawai'i
Hawai'i island, the "Big" island of Hawaii, is made of lava flows from a series of volcanos. The flows extend in all directions, but the flows on the Windward, northeastern coast, are covered in rainforest vegetation encouraged by the heavy rain. In the west and south of the island the rainfall is much lighter and less frequent. Plant growth is scanty and the lava flows can be easily seen.
A recent lava flow about 200 years old is layered over a partly eroded lava flow several thousand years old.
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The Ohia is a native plant that can tolerate dry ground |
Typical dry lava plain near Kona on the Leeward side of Hawai'i |
Small bushes on a sand dune near Kona |
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Perfect climate for Del Monte pineapples and other tropical plants |
Because the Hawaiian islands are so far from any other land, they had very limited wildlife before humans came. Only a few species were able to cross the vast ocean to colonize here.
Hawaii has no native land reptiles or amphibians and only two native mammals, a bat and a seal. The 100 species of native birds probably evolved from only about 15 original species that managed to make it across the ocean. The 1000 species of native plants evolved from fewer than 300 original species. A large proportion of all the animals and plants that existed on Hawai' i when it was "discovered" by Western Civilization in the 1700s, were "endemic", that is, they existed only in Hawai'i and nowhere else.
A favorite visitor is the Sea turtle seen here near Kona.