The pink water in Maui is caused by a phenomenon associated with non-toxic algae halobacteria. Kealia Pond became a "Pepto Bismol pink," drawing attention to the region.

Pink Water in Maui: Onlookers of the 'Pepto Bismol Pink,' Kealia Pond

People driving past Kealia Pond in south central Maui would find themselves doing a double take. Over the past week and a half, the pond has transformed into a scene reminiscent of a sci-fi film, with its water adopting a radiant pink and purple glow.


This captivating natural phenomenon in Kihei in Kealia Pond researchers is neither fake nor photoshopped. Chef and photographer Travis Morrin received a call on November 7 about the pink transformation. Initially skeptical, Morrin witnessed the vibrant 'Pepto Bismol pink' during sunset, attributing the intensity to the time of day, reduced glare, and diminished reflection. The Pacific Whale Foundation explained that Kealia Pond, once connected to the ocean, has been isolated for years, exacerbated by drought conditions in West Maui.

That Non-Toxic Algae Phenomenon

The vibrant color in Kealia Pond is attributed to algae thriving in highly saline water. Stephanie Stack, chief research biologist at the Pacific Whale Foundation, clarified that salt-tolerant algae and bacteria flourish due to elevated salt levels caused by freshwater evaporation. The resulting pink hue, enriched by beta carotene pigment akin to that in carrots, is entirely natural and poses no manmade or toxic threat.

Addressing concerns about manipulation or pranks, Stack affirmed the authenticity of the phenomenon, emphasizing nature's remarkable facets. The pond, home to unaffected fish and birds, shows no signs of significant ecological impact. Although Stack cautioned against tasting the water due to its extreme salinity, the US Fish and Wildlife Service, overseeing the refuge, confirmed the pink water's presence for the past nine days, attributing the color change to halobacteria in highly saline waters.

A Salty Situation

Kealia Pond's salinity levels, twice that of seawater, are not likely toxic, undergoing testing at the University of Hawaii. The duration of this rare phenomenon remains uncertain, but onlookers are relishing the extraordinary sight. The Hawaii Department of Health, in collaboration with the US Fish and Wildlife Service, sent samples to the university for analysis.

Preliminary findings suggest the pink hue results from halobacteria, single-celled organisms thriving in high-salinity water, deriving their rosy pigmentation from a protein called bacteriorhodopsin. The outlet's water salinity exceeds 70 parts per thousand, fostering ideal conditions for halobacteria and producing a distinctive pink color.

About Kealia Pond

Kealia Pond National Wildlife Refuge, a vital haven in the Hawaiian Islands, is nestled along Maui's south-central coast between Kihei and Ma'alaea. Spanning 691 acres, it safeguards endangered species like the Hawaiian coot and hawksbill turtle nesting grounds at Kealia Beach.

As a settling basin for a 56-square-mile watershed, the pond undergoes seasonal fluctuations, creating diverse habitats for water birds and supporting half the Hawaiian stilt population. Hosting migratory birds, especially during winter, it's a crucial site for waterfowl. The refuge draws 2,700 yearly visitors engaged in bird watching, photography, education, and habitat restoration, emphasizing its significance in preserving Hawaii's unique ecosystems.