Although none of the males observed were successfulthe females actively avoided themHeithaus said that some of the males must eventually get what they came for.
According to Heithaus, once a female has mated, she probably has enough sperm to last the entire breeding season. So when she comes off the beach after laying eggs, she's not interested in the males lurking in the shallow waters.
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Marshall said the finding that males come near the beaches at all is a "whole mating dynamic we knew nothing about. This discovery changes the whole picture of mating-strategy theory for leatherbacks."
Another insight gleaned from Crittercam footage is the persistence with which monk seals pursue females, as in the case of one following a female for three days. Some males also show what humans call "very aggressive harassment" behavior towards pups, apparently attempting, unsuccessfully, to mate with them, Marshall said.
Male monk seals have also been shown to swim out to mid-depth waters and vocalize, a behavior that Marshall said is likely related to courtship. No male has been seen successfully wooing a female with his song.
On most deployments of the Crittercam, researchers are too busy studying species' habitat and food requirements to delve into the study of courtship and mating, but on occasion their missions take on a more voyeuristic intent.
Heithaus recently joined researchers in the Florida Keys to find out what nurse sharks do outside of their well-documented, shallow-water mating area. With Crittercam attached to the shark, they followed it to deeper water.
"It turns out shallow waters are where most mating occurs," Heithaus said. "They go to deep water to rest. We haven't seen any mating there, yet."
This project is just starting and Heithaus clings to hope that Crittercam will eventually open a new window into the mating of these sharks. For now, the researchers will have to be content with the shallow-water observations of the aggressive mating tusslemales biting female fins and females twisting and rolling violently to test the males' vigor.
On another occasion, the Crittercam crew spent six months in Antarctica to study leopard seal mating behavior. But owing to a string of mishapshelicopter groundings, lost shipsthey missed the mating season.
"It was a logistical catastrophe," Marshall said. "By the time we were able to do our work, that behavior had ended, so we looked at foraging and hunting behavior instead."
Marshall hasn't given up on capturing secret mating behaviors on film. He is organizing a trip to study humpback whales at their breeding grounds in the Pacific Ocean.
"No one has seen humpback mating in the wild. This could provide the first opportunity to do that," he said.
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