I can do no better than that LiveScience headline. Why is it so many of the most fascinating cephalopod research stories are about their multi-limbed reproductive excesses?:
Dumpling squid live fast and die young, mating with multiple partners during their yearlong lives,. They make their time count, engaging in sexual encounters that can last up to three hours each.
During these trysts, the male clings to the female, grasping her and blowing water into her mantle, the bulbous part of her body behind the head. [University of Melbourne researcher Amanda] Franklin and her colleagues wanted to test just how exhausting this ritual is.
…
“We found that squid could swim for half as long after mating, and would take up to 30 minutes to restore their swimming endurance to pre-mating levels,” Franklin said. The same was true for both males and females, the researchers found.
That means less energy for foraging, avoiding predators, growing and finding future sex partners, she said. Ongoing experiments suggest that this high-intensity mating may even be part of the reason that dumpling squid have such short life spans, though those results are preliminary, Franklin said.