Oceans and seas

Hawaiian Islands Humpback Whale National Marine Sanctuary

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The Hawaiian Islands Humpback Whale National Marine Sanctuary is one of 13 sanctuaries in the National Marine Sanctuary System created under the U.S. Marine Protection, Research and Sanctuaries Act. The sanctuary's goal is to promote comprehensive and coordinated management, research, education and long-term monitoring for the endangered humpback whale and its habitat.

The Hawaiian Islands are the world's most isolated island archipelago, born of ancient volcanoes and inhabited by animals and plants derived from ancestors that found their way here over thousands of miles of ocean. According to scientists, the shallow, warm waters surrounding the main Hawaiian Islands constitute one of the world's most important habitats for the endangered humpback whale. Nearly two-thirds of the entire North Pacific population of humpback whales migrates to Hawai`i each winter. Here, they engage in breeding, calving and nursing activities critical to the survival of their species.

The sanctuary is also home to a fascinating array of marine animals, corals and plants, some of which are found nowhere else on Earth. Its cultural heritage includes Native Hawaiian traditions of living in harmony with the sea. Its waters invite activities such as diving, boating and snorkeling, and support commercial uses such as fishing and shipping.


No one knows exactly when humpback whales first began wintering in the warm, shallow waters around the Hawaiian Islands. Narrative reports from whalers document the appearance of these majestic giants in Hawai`i in the 1840s, but little evidence substantiates an earlier presence. But arrive they did, and today, the waters around the main Hawaiian Islands of Kaua`i, O`ahu, Hawai`i, Maui, Moloka`i, Lana`i and Kaho`olawe constitute one of the world's most important North Pacific humpback whale (Megaptera novaeangliae) habitats, and the only place in U.S. coastal waters where humpbacks reproduce. Scientists estimate that two-thirds of the entire North Pacific humpback whale population (approximately 4,000 to 5,000 whales) migrate to Hawaiian waters each year to breed, calve and nurse their young.

It All Began in 1982

caption The terrain and coastlines within the Hawai`i sanctuary vary significantly. Pictured here are the dramatic peaks off Kaho`olawe. (Photo: Marc Hodges)

In March 1982, the National Oceanic and Atmospheric Administration (NOAA) stated that certain areas around the Hawaiian Islands should become a national marine sanctuary. Public workshops were held to allow scientists and the community to discuss the purpose of such a sanctuary and to evaluate the issues related to the management of a sanctuary. Soon after, some members of the community voiced opposition, fearing that a marine sanctuary would bring additional restrictions on fishing and vessel traffic. In response to these concerns, Hawai`i's then-Governor Anyoshi suspended further consideration of the site in early 1984.

Six years later, in October 1990, President George Bush directed the Secretary of Defense to immediately discontinue the use of Kaho`olawe as a weapons range. Congress once again directed NOAA to determine the feasibility of establishing a national marine sanctuary in the waters around the island and elsewhere in Hawai`i.

Congress, in consultation with the State of Hawai`i, designated the Hawaiian Islands Humpback Whale National Marine Sanctuary on November 4, 1992. The Hawaiian Islands National Marine Sanctuary Act identified the following purposes for the sanctuary: to protect humpback whales and their habitat within the sanctuary; to educate and interpret for the public the relationship of humpback whales and the Hawaiian Islands marine environment; to manage human uses of the sanctuary consistent with the Hawaiian Islands National Marine Sanctuary Act and the National Marine Sanctuary Act; and to identify marine resources and ecosystems of national significance for possible inclusion in the sanctuary.

Sanctuary Designation in 1997

caption The waters off the north shore of Kaua`i are included in the Sanctuary boundary. In addition to humpback whales, other protected marine life are visible from the refuge including the Hawaiian monk seal, spinner dolphins, green sea turtles and seabirds.

In response to public concern about what a sanctuary presence would mean to the people of Hawai`i, the Act allowed the Secretary of Commerce, in consultation with the Governor, to modify the boundaries of the sanctuary to fulfill the purposes of the Act. Numerous public information meetings and hearings were held on each of the main Hawaiian Islands. The National Marine Sanctuary Program also established a Sanctuary Advisory Council, made up of user groups and government agencies, to provide advice and recommendations for the site's continued development and management.

The public, though still divided in its support, was assured that the sanctuary essentially would incorporate existing restrictions to enhance the protection of humpback whales and their habitat. Those restrictions primarily dealt with approaching and harassment of the whale population, discharge of wastes into the water, and alteration of the sea bed.

On June 5, 1997, over four years after the Hawaiian Islands Humpback Whale National Marine Sanctuary was designated the nation's 12th marine sanctuary, Hawai`i Governor Benjamin Cayetano formally approved of the sanctuary in state waters.

The NMSP periodically reviews sanctuary management plans with extensive involvement from local stakeholders and national communities. Management plan review provides an opportunity for sanctuary staff and the public to shape the future direction and management of each sanctuary. In general, during a five-year review, a Sanctuary may evaluate, and possibly revise, their operation and management framework, program areas such as education, and research, site-specific regulations, and the appropriateness of the boundary and management zones within it. The Hawaiian Island Humpback Whale Sanctuary completed its first five-year review process in 2002 by reviewing, revising and updating the existing management plan with the involvement of staff, its Sanctuary Advisory Council, the State of Hawaii and the local community. In September 2002, Governor Cayetano approved the final revised managment plan for implemetation in state waters.

The Natural Environment and Value

caption The waters around the main Hawai`ian Islands of Kaua`i, O`ahu, Hawai`i, Maui, Moloka`i, Lana`i, and Kaho`olawe constitute one of the world's most important North Pacific humpback whale (''Megaptera novaeangliae'') habitats and the only place in the U.S. where humpbacks reproduce.

The Hawaiian Islands Humpback Whale National Marine Sanctuary is actually a series of five marine protected areas distributed across the Main Hawaiian Islands. The total area of the sanctuary is about 1,400 square miles. Encompassing about half of the total sanctuary area, the largest contiguous portion of the sanctuary is delineated around Maui, Lana`i and Moloka`i. The four smaller portions are located off the north shore of Kaua`i, off Hawai`i's Kona coast, and off the north and southeast coasts of O`ahu. While this description of the sanctuary's natural environment and human use is generalized for the sanctuary as a whole, it is important to note that upon more detailed inspection, each of the five sanctuary areas has its own distinct natural character and social significance.


caption Because it is still over the hot spot, volcanic activity is still observed on the Big Island. Here, a spectacular display of molten lava is pouring into the ocean off the Southern coast of the Big Island.

The Hawaiian Islands formed one by one as the Pacific Plate of the Earth's crust moved northwestward over a stationary "hot spot." At the hot spot, magma from deep within the Earth periodically pushes through the crust to the surface, forming an island. Over millions of years, the Pacific Plate has worked like a very slow conveyor belt, moving islands away from the hot spot and providing fresh areas of oceanic crust over the hot spot so that new islands can emerge.

This hot spot phenomenon explains why the islands get older as one travels northwestward from the Big Island (the youngest island). The oldest parts of the Big Island are estimated to be no more than half a million years old, while Maui, O`ahu and Kaua`i are about 1, 3 and 5 million years old, respectively. Because the Big Island still resides over the hot spot, volcanic activity is still observed there, but the movement of the Pacific plate continues, and a new undersea volcano (Lo`ihi) appears to be growing into an island off the Big Island's southeast coast.

Climate and Oceanography

caption The underwater crater known as Molokini Crater is a striking example of a nearshore coral reef. Molokini is a favorite snorkeling and diving spot for Maui visitors and residents.

Hawai`i is famous for its comfortable climate. Air temperatures over sanctuary waters throughout the state rarely exceed 90 degrees F in the warm season (May through September) and rarely dip below 65 degrees F during the cool season (October through April). The main climate controls in Hawai`i are latitude, the Pacific Ocean and altitude. Lying between 19 and 22 degrees north latitude, the Main Hawaiian Islands are on the edge of the tropics and within the area where trade winds blow northeasterly about eight days out of ten. Because of the islands' low latitude, the longest and shortest days of the year differ by only about two hours. The Pacific Ocean supplies moisture to the air, and, because of its high heat-storage capacity, keeps temperatures within a relatively narrow range. Most differences in temperature from place to place in Hawai`i result primarily from altitude, where cooler areas are typically found at higher elevations.

Rainfall is the one climatic feature in Hawai`i that is highly variable. Kaua`i's Mount Wai`ale`ale, where average annual rainfall is around 450 inches per year, is one of the wettest spots on Earth. However, at the sanctuary headquarters in Kihei, Maui, average annual rainfall is only about 15 inches per year. The wettest time of year for most of Hawai`i is during the cooler months, from November through February, but the Kona Coast of the Big Island, where the southeastern portion of the sanctuary is located, experiences a peak in rainfall during the warmer months of March through August. In general, average annual rainfall over sanctuary waters is between 15 and 60 inches per year.

Ranging from about 70 and 80 degrees F, the surface waters of the sanctuary are relatively warm. However, water temperatures at the deepest depths of the sanctuary (around 600 feet) can be as cold as 40 degrees F. The large-scale surface current patterns in the Hawaiian Islands generally go from east to west, but winds and tidal flows add to their complexity.

Marine Ecosystems

caption These two species of fish, the Moorish Idol (''Zanclus cornutus'') and the Milletseed Butterfly fish (''Chaetodon miliaris''), can be seen amongst the spectacular corals found within sanctuary waters.

With its boundaries including waters from the shoreline to depths of 600 feet in many areas, the sanctuary encompasses a variety of marine ecosystems, including seagrass beds and coral reefs. Much of the sanctuary has fringing coral reefs close to shore and deeper coral reefs offshore. Hawai`i's coral reefs are noted for their isolation and endemism. Over 25% of all Hawai`i's reef animals are endemic, meaning that they are found nowhere else on Earth.

In Hawai`i's fringing reef ecosystems, corals and coralline algae are the dominant reef-building organisms. The corals found on the sanctuary's fringing reefs include, table coral (Acropora cytheria) rice coral (Montipora capitata), lobe coral (Pavona duerdeni), corrugated coral (Pavona varians), mushroom coral (Fungia scutaria), lace coral (Pocillopora damicornis), antler coral (Pocillopora eydouxi), cauliflower coral (Pocilopora meandrina), finger coral (Porites compressa) and plate coral (Porites rus). Other important components of the fringing reef ecosystem include algae (brown, red and green), marine invertebrates (shrimp, lobster, crabs and sea urchins) and fishes (parrotfish, wrasses, damselfish, surgeonfish, goatfish, jacks and sharks). Endangered Hawai`ian monk seals and threatened green sea turtles are also important members of the sanctuary's fringing reef community.

The deeper reefs lie in the "twilight zone" of the sanctuary below 200 feet. These deep-reef ecosystems have their own unique assemblage of corals, algae and marine invertebrates, many of which are depth-adapted versions of species found at shallower depths. Deep-reef fish include squirrelfish, soldierfish, surgeonfish, snappers and emperors. Endangered Hawai`ian monk seals and threatened green sea turtles also frequent the sanctuary's deeper reefs.

Human Uses and Economic Value of the Sanctuary

People use the resources found within the sanctuary in a variety of ways. Native Hawaiians have long had close relationships with their marine environment. Nowadays, the marine area included in the sanctuary is used extensively for ocean recreation, fishing and shipping. In sanctuary waters off of Maui, for example, commercial tour operations feature whalewatching, sportfishing, parasailing and snorkeling, while commercial fishing, cruise ships and commercial shipping use the same area. One of the main purposes of the sanctuary is to work with government agencies and the private sector to ensure that these activities are conducted in ways that have the least possible impact on humpback whales and their habitat.

The sanctuary's goal of protecting humpback whales and their habitat is very important for the continued success of Hawai`i's whalewatching industry. A recent study estimates that commercial whalewatching tours in Hawai`i support as many as 390 jobs and generate as much as $27 million annually in local revenues. Through its management activities, the sanctuary actively protects the humpback whale's significant economic contribution to the islands

The Humpback Whale

caption A competitive mating group of humpback whales. (Photo: NMFS)

The Hawaiian Islands, the most remote high islands on earth, located in the middle of the world's largest ocean, have at their heart the only national marine sanctuary dedicated to whales and their habitat. The annual migration of the humpback whales, from their summer home in icy Alaskan waters to their Hawaiian winter destination, is a miraculous feat. They can cover nearly 3,000 miles of open ocean in less than two months' time, but how they find their way remains a mystery. The reason why they come here, however, is more easily understood.

caption A humpback whale's tail is so powerful that it only takes one or two thrusts to propel the entire body out of the water. (Photo: Suzanne Canja)

Like all whales, humpbacks are mammals, and belong to the baleen whale suborder, mysticeti. They graze on zooplankton and small fishes in temperate and subpolar waters. Nearly all of the baleen whales migrate some distance to warmer tropical waters to breed and give birth. The humpback whale population that comes to Hawai`i each winter is part of a much larger group that lives in the North Pacific Ocean, with feeding aggregations distributed in the Gulf of Alaska, southeast Alaska, and central California. Many members of these feeding groups migrate southward to the tropical waters off Japan and the Ryukyu Islands, as well as to Hawai`i, Mexico and Central America in roughly parallel tracks, with very little exchange between the breeding grounds. The Hawaiian Islands Humpback Whale National Marine Sanctuary has been established in the heart of the largest breeding grounds for the humpback whale. It is estimated that approximately 2,000 to 5,000 individuals come here each year, a significant portion of the total North Pacific population of 6,000 to 10,000 whales.

Humpback whales are not the largest whales in the world, but they are certainly the most watched. They are easily seen in sanctuary waters because of their large size and distinctive physical features, their energetic surface behaviors, and their close proximity to shore.

Further Reading

  • Hawaiian Islands Humpback Whale Official Site
  • Gulko, d. 1998. Hawai`ian Coral Reef Ecology. Honolulu: Mutual Publishing.
  • Juvick, S.P. and J.O. Juvick. 1998. Atlas of Hawai`i, 3rd Edition. Honolulu: University of Hawai`i Press.
  • Utech, D. 1999. Valuing Hawai`i's Humpback Whales: The Economic Impact of Humpbacks on Hawai`i's Ocean Tour Industry. Oahu: NOAA, Hawaiian Islands Humpback Whale National Marine Sanctuary.





Disclaimer: This article is taken wholly from, or contains information that was originally published by, the National Marine Sanctuary. Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the National Marine Sanctuary should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.




Sanctuaries, N. (2014). Hawaiian Islands Humpback Whale National Marine Sanctuary. Retrieved from http://www.eoearth.org/view/article/51cbedf57896bb431f695078


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