Two humpback whales have been captured on camera in the act of copulation for the first time and, unprecedented as this was, the encounter was made all the more remarkable by the fact that both whales were male.
Maui-based photographers Lyle Krannichfeld and Brandi Romano subsequently sought the advice of Stephanie Stack, a lead researcher with the Pacific Whale Foundation in Hawaii, and the three worked together to assess, interpret and document what they had witnessed.
Their study, just published in the journal Marine Mammal Science, is described by Stack as a “significant breakthrough in our understanding of humpback whale behaviour”.
The photographers had been on a recreational boating trip when they witnessed the interaction on 19 January, 2022, and were able to capture their remarkable images by hanging their cameras over the side of the boat.
The vessel had been in neutral some 2km west of the Molokini crater off Maui when the two whales were seen approaching.
One of the humpbacks (Megaptera novaeangliae) was described as in poor health, being emaciated and covered in whale lice, and was considered the possible victim of a ship strike.
The other whale began repeatedly approaching it, using its pectoral fins to hold it in place while it initiated what were described as shallow, brief penetrations.
Male humpbacks usually conceal their penis in a “genital slit” to make themselves more streamlined while swimming, and the organ had only rarely been observed before, on one occasion while a whale was urinating. It is now thought that humpback males might also use the slit or the anus for same-sex copulation, as a form of practice or assertion of friendship or dominance.
The whales circled the boat a number of times, allowing the photographers ample opportunity to capture their images from there – it being illegal to be in the water within 90m of humpbacks in Hawaii.
There are similar restrictions on in-water encounters with whales in many parts of the world. “I do not want to encourage divers to seek out whales, as my research has shown this to cause disturbance,” Stack told Divernet.
Although this is the first time same-sex (whether homosexual or bisexual) behaviour has been reported in humpbacks, it is not considered uncommon among cetaceans.
Also on Divernet: Alien-hunters inspire world-first chat with whale, Humpback whales turn up in South-west, Humpback hits: catchy songs could circle world, Divers free ghost-netted humpback
