Kauai Rainbows
One of nature’s masterpieces is the rainbow, and the tropical climate and misty rain showers on Kauai provide many opportunities to see a rainbow painting the sky with colors. A rainbow is a dispersion of visible light which is composed of a spectrum of wavelengths, each associated with a distinct color. To see a rainbow, you have to have your back to the sun, which also has to be less than 42 degrees above the horizon with suspended droplets of water or a light mist. This only occurs in the morning and evening (the most common times to see rainbows). Each individual droplet of water acts as a tiny prism that both disperses the light and reflects it back to your eye. As you look into the sky, wavelengths of light associated with a specific color arrive at your eye from the collection of droplets. The net effect of the vast array of droplets is that a circular arc of ROYGBIV is seen across the sky.
Each water droplet in a rainbow disperses a full spectrum of colors, but from where you’re standing you will see only one of the colors from any particular drop. You will see the color that refracts at just the right angle to reach the place where you are standing. For example, you’ll see red when the angle between a beam of sunlight and the dispersed light (at the water droplet) is 42 degrees, and violet when the angle is 40 degrees.
The top of a rainbow is red and the innermost arc is violet – this is because a water droplet bends violet the most and red the least. If violet light from a single water droplet enters your eye, the red light from the same droplet will fall below your eye, and so you will not see it. To see red light you have to look at a raindrop higher in the rainbow.
A double rainbow is actually two completely different rainbows, one directly over the other, and are caused by a double reflection within the raindrops. The secondary rainbow is larger than the primary rainbow, and has its colors reversed, with violet on the top, and red on the bottom. In ancient Hawai‘i a rainbow (anuenue) symbolized the presence of a god or a chief.
Targeting Invasive Plants in Hawaii
The Nature Conservancy of Hawai‘i is using improved imaging and new software technologies to map, locate, and eliminate invasive plant species before they have a chance to threaten Hawaii’s delicate watersheds. The extremely high resolution images are made possible with better cameras that allow more area to be filmed from higher altitudes. New image resolution of up to one centimeter per pixel allows analysts to identify and map much of the younger small-leafed plants.
The work has already started with mapping for the removal of the Australian tree fern, a highly invasive plant that grows an average 30-feet high and 15-feet wide and displaces a lot of native trees. The fern began appearing in Hawai‘i in the 1970s and began spreading slowly over a 15-year period. During the last decade, the plant presented the potential to alter the Alaka‘i watershed and dominate the canopy of vegetation in the watershed.
The team will conduct aerial mapping to locate more ferns and eliminate them before they spread throughout the watershed. They can pick out plants in such detail that they can identify which are the bad ones to eliminate. After another year of mapping, they will remove the plants with low-volume herbicides on more than 5,000 Australian tree fern plants in Kauai’s forests. The herbicide technology was created by loading a compressed air gun with herbicide-filled paintballs that can target specific plants without overspraying and damaging surrounding vegetation.
The team will remap in three years to look for grow-back. In the meantime, the technology will expand to search out a long list of other small-leafed weed species spanning 20,000 acres of forest land across the state Hawai‘i, including the miconia and the strawberry guava. They are developing critical technologies with the potential to revolutionize forest conservation in Hawai‘i. These forests supply the fresh, clean water on which Hawai‘i’s people depend and are biological treasures vital to preserving the islands’ natural and cultural heritage.
Kauai Wilderness Protected
New fences have been installed on Kauai to help protect endangered species and the primary source of the island’s water supply. Two new fences in the remote wilderness of Kaua‘i have been constructed to protect one of the most important biological diverse areas in the Hawaiian archipelago, filled with incredible native Hawaiian birds, plants, and insects.
These barriers will shelter 8,000 acres of the state’s most pristine wilderness from the onslaught of invading feral animals. The fenced areas are home to some 300 endemic plant species, including 29 that are listed as endangered. Each fence is designed to prevent feral pigs and goats from gaining access to these areas of native flora and fauna. This land is also the core of the island’s watershed, a place where abundant rains and mists are soaked up and then feed the island’s rivers and its aquifer.
One fence cuts through the Alaka‘i Swamp, and the other sweeps between cliff faces in upper Wainiha Valley. The 4.5-mile-long East Alaka‘i Protective Fence follows a route through rugged upland bog-and-forest terrain and terminates at two sheer cliffs. Goats and pigs can’t get through it, and because of the cliffs, they can’t get around it. The fence protects a unique natural ecosystem and habitat for three endangered Hawaiian forest birds, the ‘Akikiki, Puaiohi, and ‘Akeke‘e, as well as Koloa ducks, Newell’s Shearwaters, and Hawaiian Petrels are also found here. The Wainiha Valley fence is just .3 miles long, taking advantage of sheer cliff walls of upper Wainiha Valley. It prevents the migration by feral animals into 6,000 acres of conservation land. Among the vast numbers of rare plants there is a native mint that was thought extinct until it was rediscovered in 2004.
Hawaiian Endangered Species
Before It’s too Late – Hawaii Isles of Extinction is a video about Hawaii’s unique plants, birds, and animals that are under threat from habitat destruction, development, pollution, and alien pests. It takes you on an unforgettable journey to some of Hawaii’s most spectacular islands to meet some of the rarest and most critically endangered creatures on the planet.
Today, with so many native species struggling for survival, this paradise has become known as the endangered species capital of the world. This video covers challenges facing the Green Sea Turtle, Hawksbill Sea Turtle, Hawaiian Monk Seal, coral reefs, plants, and Hawaiian birds. You will see the struggle many Hawaiian species face and meet the determined people who are acting to save them before it’s too late.
Hurricane Iniki Damage
The eye of Hurricane Iniki took the worst possible track, causing extensive damage throughout Kauai. According to Red Cross figures, Iniki left behind 14,350 damaged or destroyed homes on Kauai, with property damage totaling more than three billion dollars. In 1992 when the hurricane hit, there were 8,200 hotel, condo, and bed and breakfast rooms on Kaua‘i, and Iniki shut down 90% of them.
Damage from the ocean was heaviest along the south shore of Kauai where it first hit landfall, and affected shoreline hotels and condominiums. Wind damage was extremely heavy throughout the island as many homes and buildings were flattened or lost their roofs. Electric power and telephone service were lost throughout the island and only 20 percent of power had been restored four weeks after the storm. Crop damage was also extensive as sugar cane was stripped, and tropical plants, such as banana and papaya, were destroyed and fruit and nut trees were broken or uprooted.
Gusts within the hurricane were clocked at 227 miles per hour by the Navy’s Mākaha Ridge radar station, until the wind gauging equipment was blown off the mountain. The natural landscape of Kaua‘i was also affected, causing long-term effects on the island’s native flora and fauna. Much of the native forest canopy was stripped of its leaves as well as the fruit and flowers that forest birds depend on for food.
Ridges where wind gusts hit were stripped to bare rock, and in upland valleys trees were snapped and shrubs were stripped of leaves. The hurricane didn’t leave a lot of food for different species of Hawaiian honeycreeper that depend on fruit or flower nectar. Five extremely endangered forest birds, the Kaua‘i ‘akialoa (Hemignathus procerus), Kaua‘i nuku pu‘u (Hemignathus lucidus hanapepe), kāma‘o (Myadestes myadestinus), ‘ō‘ō ‘ā‘ā (Moho braccatus), and ‘ō‘ū (Psittirostra psittacea) were already on the verge of extinction when the hurricane hit Kaua‘i. None of them have been seen since.
Hurricane Iniki Track
Hurricane Iniki formed over the warm waters southwest of Baja California around September 5th 1992. Over the next few days, the depression began to strengthen and it was upgraded to a tropical storm, then to a hurricane moving steadily west northwest. Iniki (Hawaiian for sharp and piercing wind) remained on a west northwest course and continued to strengthen while passing 300 miles south of the Big Island of Hawaii with maximum sustained winds of 85 knots.
Iniki was approaching the western edge of a subtropical high pressure ridge, that is a semi-permanent feature found north of Hawaii normally keeping hurricanes south of the islands. This ridge was now weakening and caused Iniki to take a course change that would eventually turn it on a more northerly track. On September 9th it was moving at 15 knots and was 425 miles south of Honolulu.
The hurricane began to slow its forward motion during the morning hours of September 10 with top winds of 100 knots. It slowed even more and started to turn northwest about 400 miles south of Lihue, Kauai, with maximum winds now estimated at 110 knots and gusts as high as 135 knots. A hurricane watch was issued for the western Hawaiian chain from Kauai to French Frigate Shoals.
It continued to strengthen during the early morning hours of September 11 as it moved north at 15 knots. Maximum sustained winds had increased and were estimated at 125 knots with gusts as high as 150 knots. It was rapidly approaching the Kauai coast and at 3:30 pm the eye crossed the south coast of Kauai just east of Waimea and departed Haena on the north coast about 40 minutes later. Estimated maximum sustained winds over land were 140 miles per hour with gusts as high as 175 miles per hour, making Iniki the most powerful hurricane to strike the Hawaiian Islands in recent history.
