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Ocean Watch
Susan Scott
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Squid pro quo: Giant differs from colossal
WHILE reading and listening to news reports about a big squid that Patagonian toothfish fishermen caught recently, I remembered why, 20 years ago, I wanted to write this column.
To me, news stories about marine animals usually fell short. I almost always wanted to know more, and thought other ocean enthusiasts did, too.
Take this squid. The Associated Press wrote, "Colossal squid are found in Antarctic waters and are not related to giant squid found round the coast of New Zealand."
Oh. Earlier, I thought the word colossal meant a super-size giant squid. But no. Colossal squid is a new common name for a different species of deep-sea squid.
The New Zealand researchers who chose this name felt that colossal conveyed both the size and aggressiveness of the animal. This is "one of the most frightening predators out there," one said. "It's without parallel in the oceans."
Frightening to whom? I wondered. I thought the giant was the biggest squid. Is the colossal a new discovery? And what on earth is a Patagonian toothfish?
Whether the colossal or giant squid is bigger depends on what you measure and whom you ask.
My invertebrate zoology textbook shows a picture of a giant squid stranded in Norway in 1954. The creature is 30 feet long, measured from the top of the body to the tip of its longest tentacle. According to the caption, this is a small one. The largest stranded specimen was 60 feet long.
The colossal squid in the news was 39 feet long, but the New Zealand biologist studying it believes the animal is only two-thirds grown. Plus, he says, the body of the colossal is massive compared with that of the giant squid. His conclusion is that the colossal is the world's largest squid.
But researchers have to be careful here. Estimates of deep-sea squid sizes were based in the past on the size of sucker marks found on sperm whale skin. Later, however, biologist discovered that sucker scars grow with the whale, making the squid-size estimates far too large.
My take on size is that giant squids are longer but colossal squids are beefier.
The colossal is also a more formidable predator. This creature has swiveling hooks at the end of its tentacles, and the largest mouth (called a beak in this class of animals) of all squid.
Giant squid, it is believed, hang around waiting passively for a fish to swim within reach. But colossal squid are active hunters, particularly of Patagonian toothfish. Most of us know these 6-foot-long fish as Chilean sea bass, a species that is being aggressively overfished.
It doesn't matter how big or tough deep-sea squids are when it comes to their sperm whale predators. Squid put up a fight, but these whales are far more powerful and the squids nearly always lose.
Researchers have known about colossal squid since 1925, but this recent landing is the best specimen they have had to study. Only six others have been found, five in sperm whales' stomachs.
Giant and colossal squids are the sea monsters of old, but the notion that they sink ships and eat people is fiction. These squid have no interest in us or our vessels.
And that answers my questions about deep-sea squid. I hope it answers yours, too.