Ni‘ihau was formed from a single shield volcano approximately 4.89-million years ago, making it slightly younger in age than Kaua‘i.
It is approximately 70-square miles or 44,800-acres, and sea cliffs are a prominent feature of the eastern coast. Approximately 78-percent of the island is below 500-feet in elevation.
Ni‘ihau has no perennial streams. Among Ni‘ihau’s most unique natural features are several intermittent lakes.
Halulu Lake is a natural freshwater lake covering approximately 182 acres and Halāli‘i Lake is an intermittent lake covering approximately 841 acres (considered the largest lake in Hawai‘i.)
These lakes are sometimes called “playa” or “intermittent lakes.” This is because the water comes from rainfall, which only averages between 20 to 40 inches per year on Ni‘ihau. During dry years, the lakes are typically dry.
The lakes provide habitat for ‘alae ke‘oke‘o (Hawaiian coot), ae‘o (Hawaiian stilt) and koloa maoli (Hawaiian duck).
The lakes and island fit into a story about the 1941 Pearl Harbor attacks.
As early as 1924, it was reported that the military had predicted a possible attack by the Japanese on Pearl Harbor.
Back then, they even suggested that the remote and relatively vacant island of Niʻihau might be used as a staging area for the attack.
The obvious concern was that Japanese plans could land their attack planes on the open and level areas on the island.
Niʻihau owner, Alymer Robinson, took it upon himself to take precautions against the Japanese landing on Niʻihau by plowing trenches in the dry lake bed to preventing planes from landing and taking-off.
Plowing using mules began in 1933. In 1937, a small tractor was purchased to expedite the furrowing. Reportedly, they had crisscrossed the island with over 5000 miles of furrows.
The tractor continued to be used as a farm implement until around 1957.
On December 7, 1941 a Zero did crash land on Niʻihau, changing the lives of those who lived there and the lives of thousands of American citizens of Japanese descent. (I summarized that incident in a May 6, 2012 post – http://www.facebook.com/photo.php?fbid=3083845418429&set=a.1519996763190.2073258.1332665638&type=3&theater)
In 2004, I had the opportunity to visit Niʻihau (landing at a Navy facility at the top of the pali, as well as circling most of the island by helicopter.)
I saw the still-remaining furrow-work throughout the Niʻihau lakes. The image shows one of the lakes and you can see the patch-work furrows cut into the lake bottom.
The tractor used by the Robinsons is on display at the Pacific Aviation Museum Pearl Harbor. (Some photos and portions of this text are from information from pacificaviationmuseum-org newsletter and on flickr-com (WallyGobetz.))
In addition, some other Niʻihau and related photos are included in a folder of like name in the Photos section on my Facebook page.