Scientists Discover Two Remarkably Untouched Worlds Hidden in The Pacific

Researchers have discovered that Bikar and Bokak, the northernmost atolls in the Marshall Islands, represent some of the most intact ecosystems remaining in the Pacific and perhaps the world. A study published in Frontiers in Marine Science details the first comprehensive ecological baseline of these atolls, conducted in 2023 using scuba, underwater video, deep-sea cameras, and a submarine. The assessment covered sea- and shorebird populations, vegetation, turtle nesting, coral reefs, and fish assemblages from shallow reefs to the deep sea.

Study lead author Alan Friedlander, a marine ecologist at the University of Hawaii, said the atolls are "not just treasures for the Marshall Islands but for the entire planet, a gift from the community of Utirik Atoll, which has traditionally and vigilantly safeguarded these fragile ecosystems for decades." Bikar lies about 72 miles and Bokak about 239 miles from the nearest inhabited atoll. Two years after the survey, the Marshall Islands government declared roughly 18,500 square miles around the atolls as the country's first national marine sanctuary under its Reimaanlok framework, a community-led conservation vision meaning "looking toward the future."

The survey recorded 15 confirmed or likely breeding seabird colonies, at least 266 reef fish groups, 138 mesophotic fish groups, and 79 deep-sea fish groups. Fifteen open-water predator groups, including sharks, jacks, and wahoo, were observed. Fourteen groups had not been previously recorded in the Marshall Islands, and two may be species new to science. Despite similarities, the atolls differ: sea turtle nesting was almost exclusive to Bikar, with 132 green sea turtle nest pits recorded, while total reef fish biomass was higher at Bokak, which features coral-dominated reef communities. Friedlander noted the differences could stem from lagoon size, water exchange, sediment transport, or "a bit of a lottery involved as to which species show up and persist at remote locations."

Friedlander said the extensive survey offers an "unparalleled glimpse" into ecosystem function with minimal human influence, providing "the best ecological reference systems we have to better understand what we have lost elsewhere." The research team emphasized that monitoring must assess ecosystems in their full complexity, not just shallow reefs, to conserve integrity and track climate-driven change. Future studies should examine nutrient transfer and ecological connectivity between habitats. Friedlander added the Marshall Islands government "should be applauded for their foresight in protecting these global biodiversity hotspots," noting that large marine protected areas serve as globally important reference systems for understanding tropical oceanic ecosystems in the Anthropocene.