Could Warming Lead to Squid Boom?

Nov. 15, 2004 — -- As evidence mounts of possible global warming and overfishing, there may be a flip side to the dire news: an abundance of calamari.

Research has shown that many squid, octopuses and other sucker-bearing members of the cephalopod family don't appear to be too troubled by a minor increase in ocean temperature. In fact, when it's a little warmer, some thrive. Plus, as the fishing industry captures more and more of the animals' predators, such as tuna, cephalopods may see their niche expand.

"The good news is they taste great," said John Forsythe, an expert on the creatures from the National Resource Center for Cephalopods near Houston. "They're pure protein and they have no bones."

A study released last week said in the past half-century, average yearly temperatures in Alaska and Siberia have risen by about 3.6 degrees to 5.4 degrees Fahrenheit, while winters in Alaska and western Canada warmed by about 5 degrees to 7 degrees. Scientists say this evidence points to an overall trend of warming temperatures and waters worldwide.

It's uncertain how such warming could affect different animal species, but some believe that cephalopods will thrive.

"For shallow water species, warming temperatures is likely to expand their range and speed up their growth," said George Jackson, a squid expert at the University of Tasmania.

Research has shown that even a slight increase in water temperature can make the animals balloon in size. This is because their digestive enzymes work faster when warm.

"For cephalopods, temperature appears to be an accelerator," said Forsythe.

Jackson recently estimated the total body mass of the animals has already exceeded that of humans on Earth. Past research has suggested that sperm whales alone consume more than 100 million tons of squid every year. Jackson reasons if that estimate just covers squid eaten by one predator species, then their total mass must exceed that of humans, which represent half of 1 percent of the total biomass on Earth, according to the World Wildlife Foundation.