Global Climate Change Threatens Papahānaumokuākea

Laysan duck hunting brine flies. The Laysan duck (Anas laysanensis) is considered to be one of the most critically endangered waterfowl in the world, and is endemic to Hawaiʻi. Their population on Laysan Island is estimated to be between 503-682 individuals, and a relocated population on Midway Atoll National Wildlife Refuge is estimated to be close to 350 individuals. Photo by McKenzie Mudgeat

Despite its remote location in the Northwestern Hawaiian Islands, Papahānaumokuākea Marine National Monument faces a looming threat of global climate change that will affect its land and marine ecosystems, as well as its cultural resources, according to a recent report from the National Oceanic and Atmospheric Administration.

The Office of National Marine Sanctuaries Conservation Series report, Climate Change Vulnerability Assessment for the Papahānaumokuākea Marine National Monument, finds that sea-level rise, ocean acidification, ocean warming and other climate-related changes are expected to significantly affect the monument.

“Climate change is a complex issue that not only affects natural ecosystems, but also the rich cultural resources of Papahānaumokuākea,” said Daniel Wagner, Ph.D., the monument’s research specialist and a co-author of the report.

Papahānaumokuākea is the largest contiguous, fully protected conservation area on the planet.

Projected sea-level rise, combined with likely increases in the strength of storms and ocean wave energy, means that low-lying islands within the monument will be flooded, harming endangered birds such as the Laysan duck and Laysan finch, as well as large populations of seabirds.

Increased coastal erosion over the next 50 to 100 years will also deprive endangered Hawaiian monk seals and threatened sea turtles of beaches for nesting or haul-out areas. Coral reefs will also degrade because of increasing bleaching and coral disease.

Manta rays (hāhālua in Hawaiian) are large fish, weighing up to 3,000 lbs. Their wingspan can exceed 20 feet, and the largest manta recorded was 23 ft. Mantas are harmless to humans, but can be quite intimidating when seen up close due to their immense size. At one time there were thought to be several species of manta but recent DNA research by Tim Clark at the University of Hawaiʻi has shown they are all the same species. Photo by James Watt

“In creating this climate change assessment, we looked not only to climate change scientists, but to everyone that we believe will be able to address the complex issues of climate change, including managers, scientists, policy makers, economists, historians, archaeologists, cultural practitioners and educators,” Wagner said.

Covering 582,578 square miles (1,508,870 square kilometers), Papahānaumokuākea is the largest contiguous, fully protected conservation area on the planet, at nearly the size of the Gulf of Mexico.

Based on a series of expert workshops, interviews with resource managers and scientists, and a thorough review of available literature, the report identifies how and why cultural and ecological resources across the monument are likely to be affected by future climate. It is one of the first holistic reports on climate change that discusses the bio-physical effects of climate change, and how these will affect cultural resources. It was developed with input from all agencies on the Monument’s Management Board.

The feathery black coral species (ʻĒkaha kū moana in Hawaiian) was only recently discovered in the Monument, because it is typically found in waters deeper than 200 feet that are only accessible through advanced diving technologies such as technical diving or submersibles. Feathery black corals are important because they create habitat for a myriad of associated species that hide among its branches such as butterflyfishes, shrimps and crabs. Photo by Greg McFall

“Existing evidence suggests that the monument’s northernmost atolls may be among the first ecosystems to be irrevocably impacted by global climate change, thus providing early indications of what we can expect to see in other locations going forward,” said Dan Polhemus, Ph.D., who oversees the Aquatic Ecosystem Conservation team for the U.S. Fish and Wildlife Service in the Pacific Islands and co-author of the report. “In this regard, documenting climate change impacts in PMNM can provide important regional perspectives and help raise global awareness about this major threat.”

As sea surface temperatures increase, areas that already are showing reduced ability to maintain sustainable levels of ocean life are expected to expand, limiting available prey for predator species like seals and large birds. Species of special significance to Native Hawaiians, like ‘opihi, a Hawaiian limpet which grazes on algae, and other species that prey on plankton and crustaceans, will also see their sources of food decline. For some of these species unique to the Hawaiian Islands, the ability to alter their reproductive and feeding habitats may not occur quickly enough to keep up with climate change.

The masked angelfish is a rare species found most abundantly in the Northwestern Islands. This specimen is found in progressively higher concentrations as one goes west to the Northwestern Islands, indicating a preference for cooler waters. The species was first discovered in 1972 when a female specimen was found near Waikiki. Since then, male specimens have been found and the species was re-described to include sexually dichromatic differences. While the female is predominantly white with a black coloration from its lips to its gill cover and gill spine, the male counterpart is known for its bright yellow-orange colored dorsal, anal and pelvic fins. These species are protogynous hermaphrodites and generally change genders after reaching a size of about six to seven inches. Photo by Yumi Yasutake

In addition to a decline in biodiversity in the Hawaiian Islands, the authors note that sea-level rise and ocean acidification will also harm aspects of Hawaiian cultural heritage. One example is that Hawaiian tradition considers corals to be source of all life, and damage to reefs could result in loss of sense of place for Native Hawaiians. Moreover, sea-level rise, stronger storms and higher waves could inundate religious, agricultural and other formerly inhabited archaeological sites on Nihoa and Mokumanamana islands.

Visit http://sanctuaries.noaa.gov/science/conservation/pmnm-climate-change.html to download a copy of the report.

Papahānaumokuākea is cooperatively managed to ensure ecological integrity and achieve strong, long-term protection and perpetuation of Northwestern Hawaiian Island ecosystems, Native Hawaiian culture, and heritage resources for current and future generations. Three co-trustees; the Department of Commerce, Department of the Interior, and State of Hawai‘i; joined by the Office of Hawaiian Affairs, protect the monument.

Papahānaumokuākea Marine National Monument was inscribed as the first mixed (natural and cultural) UNESCO World Heritage Site in the United States in July 2010.

Visit www.papahanaumokuakea.gov for more information.

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