August 08, 2003
Sex-Crazed Giant Squid
New Zealand squid expert Steve O'Shea says he will mount a new expedition in July next year to film "sex-crazed" giant squid in the wild.
Dr O'Shea plans to film about 600m below the sea surface off the West Coast, after squirting squid pheromones, sexual scents, into the ocean.
The extracts of male and female giant squid sex organs will be squirted from a remotely-operated submersible, the latest New Scientist magazine reports.
He hopes the pheromone will attract squid long enough for a good opportunity to film them.
"These things come into New Zealand waters to breed," Dr O'Shea said of the squid. "They're sex-crazed".
In a paper submitted to the New Zealand Journal of Zoology, Dr O'Shea and his assistant, Kat Bolstad have described finding fragments of the end of a giant squid tentacle in the stomach of a female.
He said it probably was not intentional cannibalism – but the tentacle of a male swept too close to a female's "beak" during mating and she ate it.
A squid expert at the Melbourne Museum, Mark Norman, and his colleague Chung-Cheng Lu, six years ago investigated the first recorded mated female giant squid, and found sperm packages or "spermatophores" embedded in the skin of the female's arms, where it is stored until the female is ready to use it.
The pair said it seemed a male giant squid used its muscular elongated penis – up to 1.5m long – to "inject" sperm packages under pressure directly into the arms of females.
Since then, Dr O'Shea has found males implanted with their own spermatophores.
"If we are talking about a 200kg squid, this is an animal with a 20g brain," he told New Scientist.
"It's not very bright and it is trying to coordinate a metre-long penis.
"He's going to get a bit confused."
The researchers believe female giant squid – scientifically known as Architeuthis – probably mix eggs from their ovary with jelly secreted from glands inside the body. They then extrude the egg mass to be cradled in their arms in the form of a small gelatinous sphere.
Chemicals in the egg-jelly matrix activate the sperm packages buried in her arms, and the spermatophores migrate towards the surface of the skin, where they explode, shooting sperm out onto the egg mass.
The sperm then burrow into the mass to fertilise many thousands of eggs.
Dr O'Shea thinks this egg mass drifts for a week or two before the larvae hatch.
He said there were two separate geographical groups that migrated to New Zealand waters to breed. One gathered off the West Coast of South Island in July and August, the other off the East Coast in late December, January and February.
In February 2001, Dr O'Shea's team, funded by the Discovery Channel, trapped some tiny squid larvae swimming 250km east of New Zealand which turned out to be Architeuthis larvae – the first ever caught – but they all died over the next three days.
Other groups, such as a Smithsonian-led team, funded by the National Geographic Channel, are also trying to film a giant squid.