Hawaiian Monk Seal Swims from Kure Atoll to Oʻahu

Researchers expressed their amazement at one Hawaiian monk seal that swam 1,300 miles within a month.

According to the Department of Land and Natural Resources, the six-year-old female seal, designated as KG54, swam from Kure Atoll, the northernmost island in the Hawaiian chain, in Papahānaumokuākea Marine National Monument, to O‘ahu, arriving on a north shore beach adjacent to Ka‘ena Point State Park Wednesday, Sept. 22, 2021.

“We have data that shows at least 10 seals have made at least 14 different trips between the main Hawaiian Islands, the Northwestern Hawaiian Islands, and Johnston Atoll between 1981-2011 and since then, there have been several more,” stated Dr. Michelle Barbieri, the Program Lead for NOAA’s Hawaiian Monk Seal Research Program. “What’s impressive about KG54 is she made the trip in about a month, where other seals are more likely to make it over the course of several years.”

When Lesley Macpherson, an Interpretive Technician at Ka‘ena Point State Park, was first notified of a “new” seal, resting on a beach adjacent to the park, she went out to try and identify her. When she observed her, Macpherson spotted a gray-colored ID tag on the animal.

“Seals born in the main Hawaiian Islands have red tags, so it was exciting to realize she swam so far, so quickly, all by herself. It’s amazing, really amazing.”

On Saturday, KG54 rested on the deserted beach in the park, alongside RN58 (nicknamed Luana), a much fatter, eight-year-old female seal. Macpherson nicknamed the monk seal Huaka’i, which means traveler, journey, or path taken.

On Monday, Sept. 27, Macpherson reported a third seal resting on the beach, along with RN58 and KG54. Researchers also took notice of KG54’s size.

“We know she left Kure in mid-August, but we don’t know at this point her molt status,” said Barbieri.

Seals are typically lower weight after molting.

“It seems reasonable that she expended a lot of energy coming to O‘ahu. However, some seals from the NW Hawaiian Islands can be thinner than those born in the main islands, so it’s probably a combination of both factors,” Barbieri added.

She and others hope the seal refuels after her long journey before undertaking further travel.

Researchers don’t have a complete picture of monk seal movements around the islands. The experience of KG54 again demonstrates the ecological behaviors of seals.

”A 2015 study, looking back 30-years, shows seals mostly moving between neighboring islands and less often long distances,” stated Barbieri. “The ability of these animals to island-hop is what has allowed them to colonize new areas over time. Travel of up to 400-kilometers between islands is more common, unlike the one KG54 just made of 2,092-kilometers in fewer than five weeks.”

A different study verified the presence of monk seals in the Hawaiian archipelago for hundreds of years. Study author, Dr. Jack Kittinger wrote that though the prehistoric period remains poorly understood, findings suggest that monk seals were referenced in Hawaiian-language newspapers in the late 19th and early 20th centuries. References are also made to monk seals in traditional knowledge forms and in familial histories.

Brian Neilson, the Administrator of the DLNR Division of Aquatic Resources (DAR) concluded, “The arrival of Huaka‘i demonstrates the ability of seals to move over long distances and to colonize islands that are separated by hundreds and thousands of miles. This, in part, explains how they have been able to slowly rebound from such small population numbers, once confined to the Northwestern Hawaiian Islands.”

Researchers know that endangered Hawaiian monk seals range broadly across the Hawaiian archipelago. Data shows that 10-14% of adult monk seals move from their birth island to other islands.