Humpback sex photographed for first time – and both whales were male

<span>These two male humpback whales were observed mating in 2022.</span><span>Photograph: Lyle Krannichfeld and Brandi Romano</span>
These two male humpback whales were observed mating in 2022.Photograph: Lyle Krannichfeld and Brandi Romano

Humpback whales have been observed having sex for the first time, with this landmark moment having an interesting twist – the two whales were male.

Despite decades of research on humpback whales, sightings of the male’s penis have been rare. Copulation by the species had not been documented by people – until now, when two photographers captured images of a sexual encounter between two whales off the coast of Hawaii.

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The sighting, confirmed by scientists in a newly published study, occurred in January 2022 in waters west of the island of Maui, where two whales approached and circled a boat before engaging in sexual activity about three to five meters below the vessel.

Both of the whales were male, which makes the photos, taken by Lyle Krannichfeld and Brandi Romano, the first evidence of homosexual behavior in humpback whales as well as the first sighting of sex in the species. Homosexual behavior is common in the animal kingdom and has been spotted among dolphins and orca whales, but never previously between humpback whales.

Stephanie Stack, a whale researcher at the Pacific Whale Foundation and lead author of the new paper, said that the sexual behavior of humpback whales had “remained mostly a mystery until now”.

“This discovery challenges our preconceived notions about humpback whale behavior,” she said. “While we have long recognized the complex social structures of these incredible creatures, witnessing the copulation of two male whales for the first time is a unique and remarkable event.”

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Humpback whales are hefty lovers, measuring up to 16 meters (or 52ft) in length and weighing as much as 36 tons, which is the weight of several buses. The species typically spends the summer feeding in polar waters before migrating to warmer, tropical climes during fall and winter. Once threatened by commercial whaling, humpback numbers have rebounded in recent years.

During the intimate encounter photographed in Hawaii, one of the whales was seen to be holding the other in place with its pectoral fins while penetrating it. The whale underneath appeared to be ailing, being noticeably emaciated and covered in whale lice, white-colored parasites sometimes found on cetaceans.

The penises of male humpback whales are usually concealed in what is known as a “genital slit” to make it more streamlined while swimming. An unsheathed penis has only been witnessed a small number of times in the past, once while a whale was urinating.

According to the new research paper, cetaceans such as humpback whales could use the genital slit or anus for same-sex copulation, to practice reproductive behaviors or to form a social alliance or assert a sort of dominance. The study has been published in the Marine Mammal Science journal.