From 2017 to 2018, a whale swam nearly 11,265 km from Saipan in the Mariana Islands to Sayulita, Mexico.
A scarred male humpback whale named Frodo completed the longest migration recorded for this species, according to a study published on September 28 in the journal Endangered Species Research. The previous record was held by a female humpback whale that swam over 9,656 km from Brazil to Madagascar in 2001.
Male humpback whales may need to swim across the Pacific Ocean to find mates. (Photo: Ralph Pace)
When biologist Nico Ransome delved deeper into the remarkable Pacific journey of the male whale, she discovered that it had also been spotted near the Commander Islands of Russia in 2010 and 2013. Russian scientists named it Frodo after the character from the film The Lord of the Rings. Frodo not only set a distance record, but it also changes how we think about the typical migration patterns of humpback whales, according to Ransome, the lead researcher and biologist at Murdoch University in Perth, Australia, and founder of La Orca de Sayulita, a company specializing in whale research and tours.
The vast majority of the 7,500 humpback whales that breed off the western coast of Mexico migrate north to Alaska and Canada to feed during the summer. In contrast, Frodo swam around the North Pacific region. Ransome discovered that it was not alone.
A few years ago, Ransome began to take notice of the Russian whales appearing in Mexico. She identified individuals through an online database called Happywhale, which maintains the black and white fluke patterns of 30,000 humpback whales—a unique characteristic similar to human fingerprints. Marie Hill, a biologist at the Institute for Atmospheric and Oceanic Research, a co-author of the study, shared a photo she took of Frodo in the Mariana Islands in 2017 on Happywhale.
Frodo’s journey prompted Ransome, Hill, and their colleagues to examine the Happywhale database to identify other humpback whales that migrated across the Pacific. They discovered 117 individuals that migrated from Mexico to feeding areas in Russia between 1998 and 2021. Prior to this study, only 11 whales had been recorded in both Russia and Mexico.
Since 2021, Ransome has found additional Russian whales in Mexico, including a mother and calf, suggesting that Frodo’s unusual migration route may actually be a common pathway. Whales may swim such long distances to find mates, a result of the whaling industry, according to Ransome.
The population of humpback whales, marine mammals longer than 15 meters, has decreased to an estimated 1,200 in the North Pacific since the 1960s due to hunting for oil, meat, and baleen plates. The population in the western North Pacific remains threatened, according to NOAA. Hill’s surveys in the Mariana Islands from 2015 to 2018 aimed to determine whether these islands were breeding grounds for humpback whales.
Typically, whales that feed in Russia migrate south to breed in Japan, the Mariana Islands, and the Philippines. However, due to the scarcity of nearby whales, males may need to wander farther to find mates, even swimming across the ocean to Mexico. They also compete for females, as evidenced by Frodo’s numerous scars. The new migration route could explain why humpback whales sing almost daily in the area between Hawaii and Mexico.
