Jarvis Island, located about halfway between the Cook Islands and Hawaii, is an unorganized and unincorporated territory of the United States. Administered by the United States Department of the Interior and the US Fish and Wildlife Service, it is one of the southern Line Islands, and is located just 25 miles south of the equator. Though public entry to Jarvis Island is via special use permit only, it is possible to dive here, particularly if you are able to join a research team, even as a volunteer.
Dry Topside, but Incredible Underwater
Like many central Pacific Ocean islands, Jarvis Island has a desert-like landscape and is completely devoid of a freshwater lens. Though it has been at times inhabited by guano miners and colonists who were evacuated after a Japanese attack during WWII, as well as by the occasional research team, its dry landscape is not suitable for sustaining life other than endemic vines, bunch grass, and low-lying shrubs. As it turns out, this environment is perfect for the seabirds that call the island their home!
Jarvis Island supports fourteen breeding seabird species and is second only to Kiritimati Island for its avian biodiversity. In addition to the sooty terns, blue noddies, and other birds that occupy the island year-round, other birds use it as a stopping-over point during their annual migration.
Sitting atop an ancient coral cap, Jarvis Island has a massive extinct volcano lying just beneath it. The equatorial undercurrents that wash the island push nutrient-rich water up from the abyss deep below, ensuring fish of all types are well-fed and productive. Mats of soft coral and huge swathes of soft coral join forces with colorful sponges and healthy hard corals to create unspoiled reef habitats, particularly deeper down, out of the way of wave action.
Researchers have so far counted just over 250 fish species in the waters surrounding Jarvis Island, including numerous reef fish such as angelfish, Moorish idols, and other colorful varieties. Larger fish including parrotfish, jacks, groupers, and rays are abundant; in fact, their densities are second only to those found at Palmyra Atoll. The shark population is healthy as well, and submersible dives have revealed that there is also an abundance of deep sea marine life at depths between 200 and 1,000 meters.
Some remnants of past human activities remain on Jarvis Island, including what’s left of guano tramways leading from the dry central lagoon toward the beach; there are also a few sheds and a day beacon here. There is no airstrip, however there are a few offshore anchorage spots marked on nautical charts, and there is a boat landing area onshore. Thus, travel to the island may be accomplished only via boat, and since there are challenges associated with this type of travel, the island sees few visitors. However, for those divers lucky enough to overcome these roadblocks, the rewards are boundless. Should you undertake a trip to Jarvis Island, it is likely that you’ll count it among your life’s pinnacle experiences.