Papahānaumokuākea coral reefs

• Category: Marine and Oceanic Biomes.
• Geographical Location: Pacific Ocean.
• Summary: This World Heritage Site consists of a thriving coral reef community and is significant both ecologically and culturally.

Papahānaumokuākea, located in the far northwestern Hawaiian Islands, has been a United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Heritage Site since 2008 and a United States national monument since 2006. The area comprises 138,997 square miles (360,000 square kilometers) of ocean set around ten islands and atolls in an elongated 1,000-mile (1,600-kilometer) stretch of the North Pacific Ocean rich in coral reef habitats.

Because the Hawaiian archipelago is the most remote island archipelago in the world, historically, few people have established communities in the northwestern Hawaiian Islands. The monument is managed by a partnership among the U.S. Department of Commerce, the state of Hawaii, and the U.S. Department of the Interior.

This protected area has been recognized for both ecological and cultural values. It not only contains many species that are endemic (found nowhere else) or endangered, but also has spiritual significance to the traditional native Hawaiian culture as an example of human-environment kinship. The name Papahānaumokuākea refers to the joining of the sky father and earth mother, the union that was to have given birth to the Hawaiian Islands and all the people there. It was bestowed upon this marine monument (considered part of the national marine sanctuary system) to honor that tradition.

Species Diversity and Interaction

The waters of Papahānaumokuākea harbor more than 7,000 species, many of which are found only in the Hawaiian Islands archipelago. Rare species such as the threatened green sea turtle (Chelonia mydas) and the endangered Hawaiian monk seal (Monachus schauinslandi) call these waters home. The coral reefs of this remote area have largely been spared from human stressors such as pollution and habitat destruction, which plague many other tropical reefs worldwide. However, like other reefs, the Papahānaumokuākea reefs are subject to climate-change effects from rising ocean temperatures and increasing water acidity. Both warming and acidification cause physiological, biological, and ecological harm to coral reefs over short and long periods. However, a 2020 report issued by the National Oceanic and Atmospheric Administration (NOAA) found that overall, the Papahānaumokuākea reef was in good to fair condition, although the reef had been impacted by derelict fishing gear, storms, algae, and some coral bleaching.

Scientists around the world are striving to understand whether some reefs will be stronger in resisting such harm in the future, and to identify factors in their environment that could help strengthen their resistance to damaging impacts. In Papahānaumokuākea, continuous coral reef health monitoring programs are carried out to measure changes and to understand the vulnerability and responses of these reefs, as well as their habitat neighbor species. Beginning in 2016, an invasive nuisance red algae called Chondria tumulosa spread rapidly across the reef after its discovery in Manawai Atoll. This algae forms thick mats that block marine life and coral from sunlight.

Aspects of the Papahānaumokuākea coral reefs being monitored include the movements and habits of top predators, such as sharks; the spread of disease among coral colonies; the symbiotic relationship between the coral animal and the photosynthesizing algae dwelling inside the coral; and genetic structures and dynamics of various fish populations. Sharks are important for any coral reef ecosystem because of the extent to which they control and shape the ecological community and help maintain various fish populations at levels that seem to contribute to sustaining healthier reefs.

The massive scale of shark fishing for their prized fins has reduced shark populations in the ocean dramatically in recent decades. Because many shark species live on or near reefs, it is important, for reef communities and the overall balance of the marine food web, to maintain protected areas that can stand as strongholds for reef and shark conservation. Papahānaumokuākea is one such stronghold.

Genetic studies of fish populations found here are revealing some of the biological and biogeographical connections of this biome and its inhabitants to other marine ecosystems. This is yet another avenue for scientists to learn more about the ecological services reefs provide, as well as their vulnerabilities and in the precise ways intact reefs can act, as oceanographer Sylvia Earle has said, as “hope spots.”

Above the sea, there are other natural riches here. On and around the small islands of Laysan and Nihoa, for example, bird populations of Laysan and Nihoa finches, Nihoa millerbirds, Laysan ducks—perhaps the world’s most endangered ducks—and seabirds such as the Laysan albatross feed, breed, and add their inputs to the ecosystem. There are twenty-one seabird species in residence around the seemingly cramped 6 square miles (16 square kilometers) of land within the Papahanaumokuakea biome. It turns out to be more than enough terrestrial base: up to 14 million birds breed and nest on the constricted land area here, including those belonging to several endemic species.

Human Presence

The land areas of the Papahanaumokuakea biome are of archaeological significance to Native Hawaiian culture; the highest number of sacred sites on any Hawaiian-archipelago island is found on Mokumanamana here. More recent history has also made a mark, with nineteenth-century commercial whaling in the region and a military presence on some atolls. Midway Atoll, near the northwestern-most extent of Papahanaumokuakea, figured large in the World War II struggle between Japan and the United States.

Before the establishment of the national monument, these waters were entirely open to fishing, and after decades of overfishing, many fish populations in the area have declined. Currently, the only uses allowed in the monument’s waters are management activities carried out by jurisdictional agencies, research, education, and Native Hawaiian practices. Midway Atoll also accommodates a small number of recreational trips every year.

The underwater realm of the monument contains fascinating maritime history. Maritime archaeologists have discovered remains of ancient Polynesian sailing canoes, modern submersible and research vessels, U.S. Navy aircraft, British whaling ships, and other craft, all of which embody layers of the region’s seafaring history. Such windows into the past add to the uniqueness of the area and underscore the transience of man’s impact on the natural environment, as well as the importance of wise management of resources.

Environmentalists continue working to mitigate the adverse effects that people have had on the reef and surrounding area. The Papahānaumokuākea Marine Debris Project removes hundreds of thousands of pounds of marine debris from the reef each year. In 2020, during a sixteen-day cleanup, they removed more than 82,600 pounds (37,467 kilograms) of marine debris from an atoll that is part of the Papahanaumokuakea Marine National Monument. The following year, scientists embarking on a twenty-four-day cleanup removed more than 47 tons (43 tonnes) of marine debris from the monument. They also disentangled a Hawaiian monk sea, three black-footed albatross chicks, and one great frigatebird from fishing nets.

Bibliography

Carpenter, Mark. "Algae That 'Smothers' Coral Spreads at Papahanaumokuakea Marine National Monument." Hawaii News Now, 25 Oct. 2021, www.hawaiinewsnow.com/2021/10/25/algae-thats-threatening-coral-reefs-spreads-papahanaumokuakea-marine-national-monument. Accessed 20 Oct. 2024.

"Cleanup at Papahanaumokuahea Marine National Park." The Garden Island, 15 Nov. 2020, www.thegardenisland.com/2020/11/15/lifestyles/cleanup-at-papahanaumokuakea-marine-national-monument. Accessed 20 Oct. 2024.

Dale, Jonathan J., et al. “The Ecology of Coral Reef Top Predators in the PapahāNaumokuāKea Marine National Monument.” Journal of Marine Biology, 2011, doi.org/10.1155/2011/725602. Accessed 20 Oct. 2024.

Kikiloi, S. Reconnecting with Ancestral Islands: Examining Historical Relationships between Kānaka Maoli and the Northwestern Hawaiian Islands. Center for Hawaiian Studies, 2006.

Marquis, Sarah. "NOAA Report Reveals Condition of Natural and Cultural Resources of Papahanamokuakea." Phys Org, 21 Oct. 2020, phys.org/news/2020-10-noaa-reveals-condition-natural-cultural.html. Accessed 20 Oct. 2024.

"Papahānaumokuākea: World Heritage Site." National Park Service, 27 July 2023, www.nps.gov/articles/000/papahanaumokuakea-marine-national-monument-northwestern-hawaiian-islands.htm. Accessed 20 Oct. 2024.

Parrish, F. A., et al. “Hawaiian Monk Seals (Monachus schauinslandi) Foraging in Deep-Water Coral Beds.” Marine Mammal Science, vol. 18, no. 1, 2002.

"What We Do." Papahānaumokuākea Marine Debris Project, 2024, www.pmdphawaii.org/projects-1. Accessed 20 Oct. 2024.