Papahanaumokuakea and Tsunami 2011
Following a massive earthquake in Japan, a tsunami washed over the three low-lying islands of Midway Atoll National Wildlife Refuge on March 10-11, 2011 affecting the lives of Hawaiian seabirds. Surveys reveal that more than 110,000 Laysan and Black-footed Albatross chicks (about 22 percent of this year’s albatross production) were lost as a result of the tsunami and two severe winter storms preceding it.
Midway Atoll is comprised of three islands – Sand, Eastern, and Spit Islands – 1117, 366, and 15 acres, respectively. Following the earthquake, the three islands were washed by four successive waves, the tallest of which was approximately 4.9 feet. The tsunami overwashed the fringing reef and Spit Island completely, and covered approximately 60% of Eastern Island and 20% of Sand Island.
Midway Atoll National Wildlife Refuge provides significant habitat for over 3 million seabirds of 21 species. Fortunately, only 4 species were nesting at the time of the tsunami – Bonin petrels, a species that nests in burrows, the endangered Short-tailed Albatross (1 pair), Laysan Albatross (482,909 pairs), and Black-footed Albatross (28,581 pairs).
Wildlife losses at Midway Atoll National Wildlife Refuge also include at least 2000 adult birds. Wisdom, a 60-year-old albatross that recently hatched her 35th chick survived the tsunami partly due to the elevation of her nest. Due to the Bonin petrels’ behavior of nesting underground it is hard for biologists to confirm the number of casualties. The Refuge is also important habitat for the endangered Hawaiian Monk Seal, the threatened Hawaiian Green Sea Turtle, and a translocated population of the endangered Laysan Duck. Three Green Sea Turtles were found washed onto the interior of Eastern Island and were returned alive to the sea. Biologists are confident that, absent any other stressors, the Hawaiian wildlife population can rebound from this event. Photo by U.S. Fish and Wildlife Service.
Papahanaumokuakea Banks and Seamounts
There are several submerged banks in Papahanaumokuakea that were once shield volcanoes formed at the hotspot. The more studied ones are Raita Bank, St. Rogatien Bank, Pioneer Bank, Southeast Brooks Bank, and other unnamed banks. Other large seamounts built up from the ocean floor, but never emerged above the ocean’s surface.
Large precious corals, such as gold, pink, and black are found in the deep waters of the banks. Unlike shallow reef corals which are able to harness sunlight as an energy source, deep-water precious corals live in darkness and are completely dependent upon capturing plankton with their tentacles. These bank areas provide extensive habitat for fish, and Hawaiian Monk Seals have also been observed foraging in these areas.
Raita Bank is just west of Gardner Pinnacles, and the crest of Raita Bank is about 60 feet from the ocean surface. Pioneer Bank is near Neva Shoals, and the features combine to form a major coral reef ecosystem rich in biodiversity and with a variety of marine habitats. At St. Rogatien Bank, the top of the seamount is about 80 feet below the surface of the water.
A significant percentage of reef-building corals within the waters of the United States are contained within Papahanaumokuakea. While elsewhere in the world coral reefs are threatened and stressed by human activities such as coastal development, pollution, and exploitation, the remote location of the Northwestern Hawaiian Islands has helped protect its coral reefs.
Papahanaumokuakea and Lisianski Island
Lisianski Island (Papa‘apoho) in Papahanaumokuakea is a flat, sandy and coral island which covers about 380 acres. The highest point is about 40 feet above sea level, with the interior covered by native plants, and the island encircled by a white sandy beach. The land vegetation of Lisianski Island is intact and pristine, with ten indigenous species and three endemic species.
In 1805, Captain Iurii Lisianskii and his ship Neva ran aground here. In 1844, a ship picking up survivors of another shipwreck introduced mice, then rabbits were introduced, and together they devastated the island’s ecology. Feather collecting began on Lisianski about 1904, and in response to public outcry, Theodore Roosevelt established the Hawaiian Island Bird Reservation from Nihoa to Kure Atoll (with the exception of Midway). Migratory shorebirds now on the island include the Golden Plover (kolea), wandering tattler (ulili), and Bristle-thighed Curlew (kioea). The island also has the largest breeding colony of Bonin Petrels in Hawai’i, and more than a million Sooty Terns.
About twenty-four species of stony corals have been recorded from around Lisianski and Neva Shoals, with a variety of growth forms including spires, castles, and other shapes. Reef fish are abundant and diverse, as well as large numbers of Hawaiian Monk Seals and Green Sea Turtles.
Papahanaumokuakea and Necker Island
Necker Island (Mokumanamana) is a small basalt island about 45 acres in size. Although the island is the second smallest in Papahanaumokuakea, it has the second largest surrounding marine habitat with about 385,000 acres. The island has a profile with five hills, the highest being about 275 feet above sea level.
Mokumanamana is known for its numerous religious places (wahi pana) and cultural objects (mea makamae). Fifty-five cultural places are known, of which 33 are religious, 17 are shelter caves, and 2 sites are of unknown function. Because the island is small, dry, and has little soil suitable for agriculture, Hawaiians probably traveled to Mokumanamana primarily for religious purposes. In addition to constructing religious structures, Hawaiians made stone human images (ki’i pohaku) while on Mokumanamana. Other activities are indicated by the production and use of stone adzes, grindstones, stone bowls, and fishing tools.
Necker Island provides a nesting spot for thousands of sea birds, including the blue gray noddy. Terrestrial life includes land snails, spiders, ticks, and 15 endemic insects. The island is sparsely carpeted with low, nearly prostrate plants, including goosefoot shrub, bunch grass, purslane, pickle weed, and the ohai shrub.
Marine life includes gray reef sharks, manta rays, giant Trevally jacks, and gray snapper (uku). Necker Island is vulnerable to strong wave action from any direction, and therefore unfavorable for coral growth. Most corals are found in partially protected areas such as caves, overhangs, and trenches. Sixteen species of stony coral have been reported, and a great abundance and diversity of sea cucumbers, sea urchins, limpets, and lobsters are found here.
Papahanaumokuakea and Maro Reef
Maro Reef (Ko‘anak‘a) is the largest coral reef in Papahanaumokuakea, with over 478,000 acres of reef area. It is a submerged atoll with only one acre sometimes above sea level, and a complex maze of reefs that radiate out from the center. The underwater habitats of Maro Reef include shallow sandy lagoons, steep reef slopes, large coral heads, ocean pinnacles, and patch reefs.
Maro Reef has a great diversity of coral with thirty-seven species of stony corals documented, as well as rice coral (Montipora capitata), disc coral (Pavona duerdeni), and finger coral (Porites compressa). The large table coral (Acropora cytherea) and other smaller table corals are also quite common. There is also a large amount of hard, crusty coralline algae that acts like cement and holds the coral together in high surf.
The reefs support numerous butterflyfish, surgeonfish, ulua, omilu, manta rays, eagle rays, white-tip sharks, gray reef sharks, and Galapagos sharks are also a common sight in the reef’s shallow waters. Hawaiian Monk Seals are occasionally seen foraging around the reef, but there are very few areas to haul out and therefore is not considered a breeding area for the species. Except for birds, there are no terrestrial species inhabiting the island.
Papahanaumokuakea and Gardner Pinnacles
The two steep pinnacles of volcanic rock called Gardner Pinnacles (Puhahonu) comprise the smallest land area of any of the islands in Papahanaumokuakea. The highest point above sea level is 190 feet, and while the land area is only 5-acres, the underwater shelves reach outward from the pinnacles and extend over an area of 604,000 acres.
Gardner Pinnacles is known for its abundance of Giant Opihi (Cellana sandwicensis) living in the islands’ inter-tidal areas. This endemic Hawaiian limpet was once a popular food source in Hawaii for centuries, but now is very rare. Twenty-seven documented species of stony coral are found throughout the reef system including acropora table coral, while tube, stony, and soft corals. These corals provide habitat for the highest numbers of fish species in the Northwest Hawaiian Islands, some which are not found at other Hawaiian islands.
Gardner Pinnacles is home to nineteen species of seabirds, most of which breed on the steep cliffs, including the rare Blue-gray Noddy. Other birds include terns, boobies, frigate birds, ruddy turnstones, and the golden plover. However, only a single species of plant clings to its rocky surface – the succulent sea purslane. Despite its isolation, the island has a surprisingly wide array of insects, including spiders, mites, moths, centipedes, flies, beetles, isopods, and earwigs.
