Habitats and conservation
Survey reveals untouched marine havens in Pacific
Researchers evaluating two isolated Marshall Islands atolls discovered abundant wildlife from breeding seabirds to diverse deep-sea creatures.
Reported by Phys.org · · 2 min read
On the map: Fish · Corals
A scientific survey of two remote coral atolls in the Pacific Ocean has uncovered some of the world's most intact marine environments. Published in Frontiers in Marine Science, the research details extensive biological surveys of Bikar and Bokak, located in the northern region of the Marshall Islands.
The study, led by Dr. Alan Friedlander of the University of Hawai'i and Pristine Seas, provides a detailed ecological baseline from the atmosphere to the deep ocean floor. Local residents from Utirik Atoll have traditionally protected these fragile ecosystems for decades. Lying roughly 116 and 385 kilometers away from the closest inhabited island, Bikar and Bokak remain largely isolated from direct human activity.
Rich biodiversity across ocean depths
In 2023, an expedition team utilized scuba equipment, submerged video cameras, deep-water camera rigs, and a submarine to examine land, coastal, and marine environments. Following the assessment, a marine sanctuary encompassing roughly 48,000 square kilometers around the atolls was established as the nation's first national marine sanctuary.
Researchers identified 15 seabird nesting sites across the two locations, along with diverse fish populations including 266 reef fish groups, 138 deeper-dwelling fish groups, and 79 deep-sea species groups. They also documented 15 groups of open-water predators such as wahoo, jacks, and sharks. Notably, 14 of the recorded fish groups had never been documented in the country before, and two may represent entirely new species.
Distinct ecological features
Although the two atolls share similar isolation, researchers noted distinct differences between them. Green sea turtle nesting was concentrated almost entirely on Bikar, where scientists logged 132 nesting pits. Bikar also harbored greater algae variety. In contrast, Bokak exhibited higher overall reef fish biomass and was dominated by vibrant coral formations.
Scientists explained that factors such as lagoon dimensions, water circulation, sediment movement, and ecological history could account for these differences. Researchers emphasized that protecting such isolated, healthy environments offers essential reference points for understanding ocean health and guiding future global conservation work.
