Explore the Central Pacific

The Pacific Ocean makes up approximately one-third of the Earth’s surface. This vast expanse of ocean is home to nearly 25,000 islands. Among these islands stretching 2,350 km in a northwest-southeast direction approximately 1,000 miles south of the Hawaiian Islands are a chain of eleven atolls called the Line Islands.  The geological history of the Line Islands is complex. It is thought that the islands formed as volcanoes over a series of hot-spots. Today only 11 of these islands are visible, at best, a few meters above sea level.  The remote nature of these islands, coupled with the biodiversity found here make them ideal areas to study coral reefs.

Marine National Monument

The Pacific Remote Islands Marine National Monument is a group of unorganized, mostly unincorporated United States Pacific Island territories in the Central Pacific, managed by the Fish and Wildlife Service of the United States Department of the Interior. Proclaimed a national monument on January 6, 2009 by U.S. President George W. Bush, the monument covers 86,888 square miles (55,428,480 acres), spanning areas to the far south and west of Hawaii, including Kingman Reef, Palmyra Atoll, Howland Island, Baker Island, Jarvis Islands, Johnston Atoll, and Wake Island.

Within the national monument, resource destruction or extraction, waste dumping, and commercial fishing will be prohibited, but research, free passage, and recreation will be allowed. Additionally, NOAA manages three marine sanctuaries in the Pacific Islands Region including the Papahānaumokuākea Marine National Monument, the Hawaiian Islands Humpback Whale National Marine Sanctuary, and the Fagatele Bay National Marine Sanctuary. The sanctuaries provide protection for a multitude of marine species including sea turtles, dolphins, whales, pearl oysters, giant clams, coconut crabs, large groupers, sharks, humphead wrasses, and bumphead parrotfishes. Expansive shallow coral reefs and deep coral forests – with some corals up to 5,000 years old – are found here. These small dots of land in the midst of the ocean are vital nesting habitat for millions of seabirds and resting habitat for migratory shorebirds. Protecting and studying these special ocean areas provides an opportunity to secure the future of our marine resources and to better understand the functioning of our oceans. Ecological knowledge is key to reef management and restoration, and ongoing monitoring and evaluation of the status of reefs are essential components of these efforts. The system of marine sanctuaries and national marine monuments hopes to help manage and preserve these valuable coral reed ecosystems for generations to come. Read National Geographic’s article announcing marine reserve.

The Southern Line Islands are home to among the most intact and pristine coral reefs on the planet. The islands are all uninhabited and are protected as wildlife sanctuaries by the Republic of Kiribati. There is discussion to extend broader protections to the marine resources of these islands, much like the great efforts of protection in the Kiribati Phoenix Islands Protected Area. However, large-scale marine conservation is challenging and demands investment from beyond just the people of Kiribati. As a global community we need to find ways to facilitate the conservation ethos of our friends in Kiribati.

A Unique Natural Experiment

The atolls of the Line Island chain span several oceanographic and climatic zones. As a result, the terrestrial characteristics of the islands vary from lushly vegetated to nearly desert-like terrains, while the submerged coral reef fauna is subject to varying influences of the El Niño phenomenon. Furthermore, although the Line Islands archipelago is the most isolated collection of islands on the planet—no continent is closer than 5000 km from any of the Line Islands—the chain is now characterized by concentrated pockets of human disturbance; this concentration of human influence has important implications for the study of island resource management. All of these aspects of the Line Islands make the archipelago an essential natural laboratory for understanding the development, evolution, and governing processes of the tropical atoll environment.”

In general, the Line Islands are characterized by uniformly low-lying topography, with elevations rarely exceeding 10 m above present mean sea level. Terrestrial substrates are typically reef sands and rubble, but one notable feature of many of the islands is that the coral rubble can reach boulder size (these coral boulders were presumably deposited by either past tsunamis or large storms).

The characteristics of the Line Islands are shaped not only by their geological history but also by their location with respect to major oceanographic and climatic zones. The southern Line Islands fall within the westward-flowing south equatorial current.

The Line Islands are one of the longest island chains in the world and are geographically divided into two subgroups; the Northern and Southern Line Islands.

The Northern Line Island chain, where our team visited in 2005 and 2010, is comprised of both inhabited and uninhabited islands, making it the perfect area for exploration and scientific discovery. The ecological research taking place in the Northern Line Islands provides valuable insights into the workings of coral reefs and how these can be altered by human activities. While we depend upon coral reefs to provide food and coastline protection worldwide, we currently lack a clear understanding of how best to use (and not overuse) these resources. The Northern Line Islands serve as a natural experimental system that spans a gradient of human disturbance, from pristine to moderately impacted by people.

The Southern Line Islands are all uninhabited islands within the Republic of Kiribati. These islands protect some of the most pristine and intact coral reefs remaining on the planet, and serve as an invaluable setting to study how coral reefs work in the absence of human disturbance. Interestingly, these islands span a wide range of natural, oceanographic conditions, with the local waters ranging from very nutrient-poor to higher-nutrient upwelling zones. The Southern Line Islands present an unparalleled opportunity to study how oceanographic conditions alter the ecology of a coral reef independently of any effects of humans.

Locations and populations for the Line Islands from North to South:

Kingman Reef population 0 6°24′N 162°24′W   |   Palmyra Atoll population 4 5°52′N 162°6′W   |   Teraina population 1,155 4°43′N 160°24′W   |   Tabuaeran population 2,539 3°52′N 159°22′W   |   Kiritimati population 5,115 1°53′N 157°24′W Jarvis Island population 0 0°22′S 160°03′W   |   Malden Island population 0 4°01′S 154°59′W   |   Filippo Reef population 0 5°30′S 151°50′W   |   Starbuck Island population 0 5°37′S 155°56′W Millenium Island population 0 9°57′S 150°13′W   |   Vostok Island population 0 10°06′S 152°25′W   |   Flint Island population 0 11°26′S 151°48′W

The Republic of Kiribati

The Republic of Kiribati was founded in 1979. Made up of 33 atolls and one island the Republic of Kiritimati is scattered over nearly two million square miles in an ocean region largely thought of as the South Pacific.  Within this vast area lie the Line Islands, a group of mostly atolls, approximately 1,000 miles south of the Hawaiian Islands. The Line Islands are remote and far from bustling cities and active airports. Their distance from civilization created a history is full of explorers, pirates, and fortune hunters. Their location also makes them the perfect place to study and conserve the practically untouched coral reefs that dominate the underwater landscape.

Northern Line Islands

Southern Line Islands

Content borrowed from Scripps Institution of Oceanography, Line Islands Expedition 2009 , Wikipedia, and The Nature Conservancy.

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