Love at first bite: The bizarre, parasitic mating ritual of the anglerfish caught on video
1st-of-its-kind footage shows male anglerfish latching on to his female host
If there truly are plenty of fish in the sea, somebody forgot to tell the poor anglerfish.
The deep-sea creature appears to take its cue from that line in South Pacific's Some Enchanted Evening: "Once you have found her, never let her go."
And now, for the first time ever, the parasitic mating ritual between a tiny male anglerfish and his much larger female host has been captured on video.
Ted Pietsch, a professor at the University of Washington's School of Aquatic and Fishery Sciences, was one of the first people to view the footage, which was captured near Portugal by wildlife photographers Kirsten and Joachim Jakobsen for the Rebikoff-Niggeler Foundation, and released exclusively through Science Magazine.
"It's so difficult to get together in the deep sea, for a male to find a female. The best thing to do is to latch on and stay on for life," Pietsch told As It Happens host Carol Off.
"This is the way they reproduce."
The anglerfish live at a depth of 800 metres under the North Atlantic.
For better or worse, 'til death do us part
Once he's committed, the male can never change his mind — he is forever joined to his partner.
"The male cannot release himself because the tissues of the male and female fuse, and also the circulatory systems fuse so that her blood flows through him, and he's nourished by the nutrients in her blood," Pietsch said.
So what's in it for the female?
"She probably doesn't even know the male is there," Pietsch said.
"But she is then able to pass on her genes. Her ovaries get very large, she releases this mass of eggs — and at the same time the male releases his sperm.
"And this can happen over and over again throughout the life of the couple. They might live maybe 25 years, and they're always together, so they can always reproduce."
Love or death
What is perhaps most extraordinary about the footage, however, is the miniscule odds of ever witnessing the sexual bonding of these deep-sea fish in their natural habitat — let alone capturing it on video.
"By far the vast majority of males down there never find a female and they die," Pietsch said.
"They can't feed on their own because they're not equipped to eat — they don't have the right jaw mechanism. They're equipped to bite on to the female. That's about all."
Conversely, few females ever manage to attract a male with whom to bond — as few as 10 per cent, Pietsch said.
"It's a crazy thing to think that 80 to 90 per cent of the females are vegetative and never give rise to offspring."
Written by Kevin Ball. Interview produced by Julian Uzielli.