Hanauma (ˌhɑːnəˈuːmə, həˈnɔumə) is a marine embayment formed within a volcanic cone

Volcanic cone

Volcanic cones are among the simplest volcanic formations. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and size of the fragments ejected during the eruption...

  and located along the southeast coast of the Island of Oahu

Oahu

Oahu or Oahu , known as "The Gathering Place", is the third largest of the Hawaiian Islands and most populous of the islands in the U.S. state of Hawaii. The state capital Honolulu is located on the southeast coast...

 (just east of Honolulu

Honolulu, Hawaii

Honolulu is the capital and the most populous city of the U.S. state of Hawaii. Honolulu is the southernmost major U.S. city. Although the name "Honolulu" refers to the urban area on the southeastern shore of the island of Oahu, the city and county government are consolidated as the City and...

) in the Hawaiian Islands

Hawaiian Islands

The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll...

.

Hanauma is one of the most popular tourist destinations on the Island and has suffered somewhat from overuse (at one time accommodating over three million visitors per year). In 1956, dynamite was used to clear portions of the reef to make room for telephone cables linking Hawaii to the west coast of the US.

Name

The word hana means bay

Bay

A bay is an area of water mostly surrounded by land. Bays generally have calmer waters than the surrounding sea, due to the surrounding land blocking some waves and often reducing winds. Bays also exist as an inlet in a lake or pond. A large bay may be called a gulf, a sea, a sound, or a bight...

 in the Hawaiian language

Hawaiian language

The Hawaiian language is a Polynesian language that takes its name from Hawaii, the largest island in the tropical North Pacific archipelago where it developed. Hawaiian, along with English, is an official language of the state of Hawaii...

 (the usual addition of bay in its name is thus redundant). There are two etymological

Etymology

Etymology is the study of the history of words, their origins, and how their form and meaning have changed over time.For languages with a long written history, etymologists make use of texts in these languages and texts about the languages to gather knowledge about how words were used during...

 interpretations of the second part of its name. One interpretation derives it from the Hawaiian word for curve, referring to either the shape of the feature or to the shape of the indigenous canoe

Canoe

A canoe or Canadian canoe is a small narrow boat, typically human-powered, though it may also be powered by sails or small electric or gas motors. Canoes are usually pointed at both bow and stern and are normally open on top, but can be decked over A canoe (North American English) or Canadian...

s that were launched there. Another stems from the indigenous hand-wrestling game known as "Uma".

Marine life

Hanauma is both a Nature Preserve and a Marine Life Conservation District (the first of several established in the State of Hawaii). Reflecting changes in attitude, its name has changed over time from Hanauma Bay Beach Park to Hanauma Bay Nature Preserve. Visitors are required by law to refrain from mistreating marine animals or from touching, walking, or otherwise having contact with coral

Coral

Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...

 heads, which appear much like large rocks on the ocean floor (here, mostly seaward of the shallow fringing reef off the beach). It is always recommended to avoid contacting coral or marine rocks as cuts to the skin can result and neglecting such wounds may bring medical problems.

About 400 species of fish are known to inhabit the bay. Hanauma Bay is known for its abundance of Green sea turtle

Green Sea Turtle

The Green sea turtle or green turtle is a large sea turtle of the family Cheloniidae. It is the only species in the genus Chelonia. Its range extends throughout tropical and subtropical seas around the world, with two distinct populations in the Atlantic and Pacific Oceans...

s, Chelonia mydas, known as Honu. Hanauma is a nursery ground for the immature turtles, which have their nesting grounds at French Frigate Shoals

French Frigate Shoals

The French Frigate Shoals is the largest atoll in the Northwestern Hawaiian Islands. Its name commemorates French explorer Jean-François de La Pérouse, who nearly lost two frigates when attempting to navigate the shoals...

. It is also known for its abundance of parrotfish

Parrotfish

Parrotfishes are a group of fishes that traditionally had been considered a family , but now often are considered a subfamily of the wrasses. They are found in relatively shallow tropical and subtropical oceans throughout the world, but with the largest species richness in the Indo-Pacific...

.

Geology

The Hawaiian Islands

Hawaiian Islands

The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll...

 are a group of volcanoes that have risen up over a hot spot

Hotspot (geology)

The places known as hotspots or hot spots in geology are volcanic regions thought to be fed by underlying mantle that is anomalously hot compared with the mantle elsewhere. They may be on, near to, or far from tectonic plate boundaries. There are two hypotheses to explain them...

, which is a section of the Earth's surface that has exhibited volcanism

Volcano

2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...

 for an extended period of time. Volcanic chains such as the Hawaiian Islands form as a result of the movement of a tectonic plate across fixed hot spot beneath the surface. In the case of the Hawaiian Islands, the Pacific plate has moved slowly northwestward over such a hotspot.

Approximately 3.9 million years ago, the Waianae volcano

Waianae Range

Waianae Range is the eroded remains of an ancient shield volcano that comprises the western half of the Hawaiian Island of Oahu...

 created the island of Oahu. About 2.5 million years ago, the Koolau volcano

Koolau Range

Koolau Range is a name given to the fragmented remnant of the eastern or windward shield volcano of the Hawaiian island of Oahu. It is not a mountain range in the normal sense, because it was formed as a single mountain called Koolau Volcano...

 erupted on the ocean floor, and continued to grow in elevation until about 1.7 million years ago, when it went dormant. Most of the eastern or windward portion of Oahu are remnants of this volcano. Most of the familiar geographic landmarks of eastern Oahu were created by eruptions from Koolau from about 500,000 to 10,000 years ago. The eastern flank of the Koolau volcano including the caldera

Caldera

A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters...

 slid into the sea, leaving the Koolau mountain range that can be seen today on the windward side of the island.

The Hanauma Crater was created about 32,000 years ago during the Honolulu volcanic series

Honolulu Volcanic Series

The Honolulu volcanic series is a set of volcanic events on the Hawaiian island of Oahu. The events, which have been dated to between 800,000 and 30,000 years before the present, created several notable island features, including Diamond Head, the Punchbowl Crater, and Hanauma Bay.The composition...

, the latest (and perhaps final) burst of volcanic activity to occur on Oahu. Tens of thousands of years ago, a series of volcanic vents opened along the southeast shoreline of Oahu. Unlike the gentle lava flows currently building the island of Hawaii

Hawaii (island)

The Island of Hawaii, also called the Big Island or Hawaii Island , is a volcanic island in the North Pacific Ocean...

, the late-stage eruptions on Oahu were violent explosions. The volcanic vents that formed Hanauma Crater opened on the sea floor. Upwelling magma vaporized the ocean water and steam explosions atomized the magma into fine ash. The explosions built cones of ash, which solidified into tuff

Tuff

Tuff is a type of rock consisting of consolidated volcanic ash ejected from vents during a volcanic eruption. Tuff is sometimes called tufa, particularly when used as construction material, although tufa also refers to a quite different rock. Rock that contains greater than 50% tuff is considered...

. The eruptions shattered the sea floor—coral reef and basalt

Basalt

Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

—and scattered pieces that are now embedded in the tuff. Wave erosion eventually cut through the low, southeast wall of the crater, forming the current bay.

Human history

Due to the lack of fresh water in the vicinity, the area was not inhabited, although archeologists have found fishing tools and other indications of human presence there. The bay was used as a recreational area by the Hawaiian nobility (Ali'i

Ali'i

Alii is a word in the Polynesian language denoting chiefly status in ancient Hawaii and the Samoa Islands. A similar word with the same concept is found in other Polynesian societies. In the Cook Islands, an ariki is a high chief and the House of Ariki is a parliamentary house...

), including King Kamehameha and Queen Ka‘ahumanu, who fished, entertained visitors, and sponsored games there. It was also used as a layover and as a navigational lookout point, since the waters between Oahu and Molokai

Molokai

Molokai or Molokai is an island in the Hawaiian archipelago. It is 38 by 10 miles in size with a land area of , making it the fifth largest of the main Hawaiian Islands and the 27th largest island in the United States. It lies east of Oahu across the 25-mile wide Kaiwi Channel and north of...

 are at times difficult.

Hanauma Bay was purchased from the Bernice Pauahi Bishop

Bernice Pauahi Bishop

Bernice Pauahi Bishop , born Bernice Pauahi Pākī, was a Hawaiian princess, philanthropist, alii, and direct descendant of the royal House of Kamehameha. She was the great-granddaughter of King Kamehameha I and last surviving heir...

 estate by the City and County of Honolulu, and subsequently opened for public use. It was initially a favorite fishing and picnic spot for residents who were willing to travel out to the bay. In the 1930s the road along Hanauma Bay's corner of Oahu was paved and a few other amenities provided that made it easier to visit the beach and reef. After the 1941 attack on Pearl Harbor

Attack on Pearl Harbor

The attack on Pearl Harbor was a surprise military strike conducted by the Imperial Japanese Navy against the United States naval base at Pearl Harbor, Hawaii, on the morning of December 7, 1941...

, barbed wire was placed at the beach and a bunker was constructed for use by sentries. The Bay area reopened after the war and became even more visitor friendly after blasting in the reef for a transoceanic cable provided room for swimming. Hawaii-themed films and television shows, including Blue Hawaii

Blue Hawaii

Blue Hawaii is a 1961 musical film set in the state of Hawaii and starring Elvis Presley. The screenplay by Hal Kanter was nominated by the Writers Guild of America in 1962 in the category of Best Written American Musical. The movie opened at no...

, Paradise, Hawaiian Style

Paradise, Hawaiian Style

Paradise, Hawaiian Style is a 1966 musical comedy film starring Elvis Presley. It was the third and final motion picture that Presley filmed in Hawaii. The film reached #40 on the Variety weekly box office chart, earning $2.5 million in theaters....

, Tora! Tora! Tora!

Tora! Tora! Tora!

is a 1970 American-Japanese war film that dramatizes the Japanese attack on Pearl Harbor, to the extent these facts were known at the time of production. The film was directed by Richard Fleischer and stars an all-star cast, including So Yamamura, E.G...

, Hawaii Five-O

Hawaii Five-O

Hawaii Five-O is an American police procedural drama series produced by CBS Productions and Leonard Freeman. Set in Hawaii, the show originally aired for twelve seasons from 1968 to 1980, and continues in reruns. The show featured a fictional state police unit run by Detective Steve McGarrett,...

, and Magnum, P.I.

Magnum, P.I.

Magnum, P.I. is an American television series starring Tom Selleck as Thomas Magnum, a private investigator living on Oahu, Hawaii. The series ran from 1980 to 1988 in first-run broadcast on the American CBS television network....

, shot footage at the bay.

In 1967 it was set apart by the State division of Fish and Game as a Marine Protected Area, a term used generically to describe any marine area that had some or all of its resources protected. In Hanauma Bay's case everything became protected, from the fish to the reef, to the sand itself. A volunteer group set up a booth at the beach and began teaching visitors about conservation of the reef and fish who lived there. More changes in the 1970s by the City cleared more area in the reef for swimming, made an additional parking lot, and shipped in white sand from the North Shore, leaving Hanauma Bay increasingly more attractive to visitors.

By the late 1980s the bay had become a major attraction on Oahu. Tourists were brought in by the busload and sometimes as many as 13,000 visitors descended on the beach in one day. Most were uneducated about the fragile marine ecosystem and, unwittingly, "these crowds stirred up sediment, disturbed and trampled the coral and algae, dropped trash, fed the fish and left a slick of suntan lotion on the bay's surface." Consequently, the beautiful multicolored coral reef closest to the beach died; only its blackened skeleton is visible today.

By 1990 overuse of the beach and surrounding area was a real problem, with visitors walking on the reef, swarming the surrounding areas, parking on the grass and on the sides of the road. Commercial filming was banned during that year. Measures were taken to limit use and so visitor access was limited to the parking lot, and when it was full everyone after was turned away. In 1997, the city of Honolulu levied an entrance fee on non-residents of the state, leading to a class action

Class action

In law, a class action, a class suit, or a representative action is a form of lawsuit in which a large group of people collectively bring a claim to court and/or in which a class of defendants is being sued...

lawsuit by a visitor, which was settled in favor of the city during 2004. Then in August 2002 the Marine Education Center was opened at the entrance to the bay, where still today new visitors must watch a short film and receive instruction about conservation of the Bay's resources. Upon watching the film, visitors are allowed to sign a form and skip any subsequent film if they should return within the following 365 days.

Today Hanauma Bay sees an average of 3000 visitors a day, or around a million visitors a year. The majority are tourists. The Bay is closed to tourists on Tuesdays in order to allow the fish a day of feeding without interruption by swimmers.

Toilet Bowl

Along the left point is the Toilet Bowl, a natural spa tub that gently rises and falls with the tide. The Bowl has been closed due to injuries suffered by visitors.

External links

• Hanauma Bay Nature Preserve – official website, City & County of Honolulu
• Hanauma Bay Education Program – University of Hawaii Sea Grant Hanauma Bay Education Program. Volunteer Program, Outreach Program, School Visits.
• Friends of Hanauma Bay