Post-Coital Fatigue Can Be Deadly for ... ... Squids, which are exhausted by 3-hour sex marathons By Neal Colgrass, Newser Staff Posted Jul 21, 2012 3:52 PM CDT 15 comments Comments This squid looks pretty tired. (Shutterstock) (Newser) – Luckily most of us don't have to hunt for food or dodge predators right after mating. But squids aren't so lucky, and strenuous sex romps leave them exhausted for about half an hour, the New Zealand Herald reports. Researchers in Australia studied the "southern dumpling squid" and saw just how pooped they were after their typical sex encounter with multiple partners for up to 3 hours. "We predict that during this phase of muscle fatigue, squid may hide in the sand to avoid predators until they have recovered," said Amanda Franklin, a researcher at the University of Melbourne. "The cost to them in doing this of course is that they cannot forage for food or search for other mates at this time." Squid sex—in which the male grabs the female from below and holds on tight—is so strenuous that it may even shorten their lifespans, said Franklin.