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Necker Island: Maps and Imagery
Necker
Island map:
View the full-resolution version.
Necker
Island IKONOS image:
View the 13m-resolution version (416 KB).
View the 8m-resolution version (831 KB).
Necker
Island bathymetry image:
View the 13m-resolution version (434 KB) with depth scale .
Download the 4-meter resolution geotiff (9,624 KB zip file). See the Digital number (DN) to Classification matchup for NWHI bathymetry files.
See the legend PDF to view the colorbars for the depth scales and the legends for habitat cover and detailed class.
Image
of Necker Island habitat cover:
View the 13m-resolution version (481 KB) with legend.
Download the 4-meter resolution geotiff (612 KB zip file) . See the Digital number (DN) to Classification matchup for NWHI habitat cover files.
See the legend PDF to view the colorbars for the depth scales and the legends for habitat cover and detailed class.
Necker
Island detailed habitat image:
View the 13m-resolution version (485 KB) with legend.
download the 4-meter resolution geotiff (639 KB zip file) . See the Digital number (DN) to Classification matchup for NWHI detailed classification files.
See the legend PDF to view the colorbars for the depth scales and the legends for habitat cover and detailed class.
Necker Island: Shapefiles
Click on the links below to download shapefiles which correspond to the French Frigate Shoals detailed habitat class and aggregated cover imagery. Each zipped shapefile consists of 6 separate files, with the same root name and .dbf, .prj, .sbn, .sbx, .shp, and .shx extensions.
Necker
Island: Detailed habitat shapefile (12 MB)
Necker
Island: Habitat cover shapefile (11 MB)
download a .ZIP file which contains the Arc and PCI legend files (.avl and .rst extension) for the NWHI maps. When added to your Arc or PCI project, these files will cause the vector colors to match the geotiffs.
Necker Island: Description and History
Necker Island is all that remains of an estimated 10 million-year-old shield volcano. Geologists believe that the portion of the volcano above water was once as large as the current size of the island of O'ahu. Now, the highest point on Necker is about 112 m above sea level. Wave erosion has reduced the volcano to a submerged shelf about 65 km long in a NW-SE direction and about 24 km wide. Necker Island itself is about 1.1 km long and less than 0.3 km wide, with steep sea cliffs on all sides.
Necker Island is surrounded by a shallow (< 50 m) shelf, which covers an estimated 1,314 sq. km This shallow shelf is subjected to severe wave action throughout the year, which directly impacts the bottom and continually moves sand across the shelf areas. Abrasion and burial inhibit shallow-water coral reef development, so coral coverage is low. In deeper water, the shelf generally shows low relief and low slope. Sand covers the underlying volcanic basalt in many areas.
At least 52 archaeological sites have been identified on Necker Island. Many of these sites are Tahitian. Artifacts from some of these archeological sites are on display at the Bishop Museum in Honolulu.The spine of the island is dott ed with 33 religious shrines, marae or ahu, unusually built with upright stones of thin basalt. The location and design of the shrines suggest that the island was visited in ancient times primarily for spiritual purposes. Various theories suggest that the shrines were built for rituals focused on birds, similar to the birdman cult of Rapa Nui (Easter Island). They also may be solar shrines focused on the travel of the sun because the island lies on the Tropic of Cancer. Similarly constructed shrines once existed at other remote, extreme locations in Hawai`i including Haleakala on Maui, and Mauna Loa and Mauna Kea on the Big Island.
Necker Island was "rediscovered" and named in 1786 by Jean Francois de Galaup. He reported that, due to the terrain and the strong waves and currents, landing was not possible on the island. Necker is essentially a barren island and supports only six known species of plants. Despite this, at least 60,000 birds of 16 species rest and nest there each year.