In brief

• Researchers describe the Bikar and Bokak atolls in the Marshall Islands as among the most intact marine ecosystems in the Pacific.
• A 2023 expedition recorded 266 reef fish groups from 38 families, with sharks making up up to 33.9 per cent of fish biomass.
• The Marshall Islands made the surrounding waters a national marine protected area covering about 48,000 square kilometres in 2025.

A remote reef system with few human footprints

Researchers say the coral atolls of Bikar and Bokak, part of the Marshall Islands, are among the most intact marine ecosystems in the Pacific and perhaps anywhere on the planet. The atolls lie far from inhabited areas: Bikar is more than 100 kilometres from the nearest populated atoll, and Bokak almost 400 kilometres from places where people live. (У Тихому океані знайшли місця, яких майже не торкнулася людина: що виявили дослідники – UNIAN) (Сотни видов. В Тихом океане обнаружили два почти нетронутых коралловых атолла с богатой экосистемой – NV) (У Тихому океані виявили два майже недоторкані світи: що приховують віддалені острови – TSN)

What the expedition found

A 2023 expedition recorded 266 groups of reef fish belonging to 38 families. Fish biomass was higher around Bokak than around Bikar. Sharks made up a large share of that biomass: 26.8 per cent on the outer reef slopes of Bikar and 33.9 per cent on Bokak. Researchers also used underwater vehicles to survey deeper water down to 275 metres, where they logged 138 further fish groups, 14 of which were probably not previously recorded in the Marshall Islands.

The team also counted 15 colonies of breeding seabirds and documented nesting sites for sea turtles. Giant clams with zebra-like striped shells and green sea turtles were among the species observed. (Bikar und Bokak: Ein Naturparadies im Pazifik zeigt, was andere Orte verloren haben – DER SPIEGEL)

Protection and next steps

The Marshall Islands declared the waters around the two atolls the country's first national marine protected area in 2025. The reserve covers about 48,000 square kilometres. (У Ціхім акіяне знайшлі месцы, якія амаль не зазналі ўплыву чалавека – Nasza Niwa)

Marine ecologist Alan Friedlander of the University of Hawaii, who led the work, described the atolls as treasures for the whole planet, not only for the Marshall Islands. Researchers said the local Utirik community plays a role in safeguarding the sites. The findings were published in the journal Frontiers in Marine Science. (Scientists find some of the 'very last wild and healthy ecosystems' in the world's oceans untouched by humans – Phys.org)