Two dispatches from the never-ending war between sea creatures and land beasts. First, to the sea, where researchers from Dalhousie and Stanford have found evidence squid can fly faster than they swim. Dalhousie’s Ronald D’Or and his colleagues confirmed the discovery by studying high-speed photos shot in the waters near Brazil.
Because they knew the intervals of time between each photo, O’Dor and his colleagues were able to estimate the squid’s velocity and acceleration, and compare them with these values for squid in water. They found that the velocity in air while the squid were propelling themselves with the water jet was five times faster than than any measurements O’Dor had made for comparable squid species in water.
“It makes perfect sense that these species are using flight as a way of saving energy,” says O’Dor. Some species spend vast amounts of energy migrating each year; for example, I. illecebrosus travels more than 1,000 kilometres down the North American coast to spawn.
“I could never explain how they could get this much energy”, even given evidence that females eat the males as they make the journey, says O’Dor. “As soon as we thought about the possibility that these things flew, it became plausible that these animals actually use flight as a way of reducing energy cost.”
New research on land, meanwhile, has found cougars on B.C.’s coast have a much more diverse diet than anyone previously believed. Analysis of scat samples taken on Vancouver Island showed traces of harbour seals, sea lions and relatively huge amounts of raccoon.
From the Vancouver Sun:
“I know of no other account of cougars eating a marine mammal [, says Victoria researcher Chris Darimont.] But I’m not completely shocked. There is some pretty delicious seafood out there. Seals are loaded with calories, fat and protein. They’re big prizes, and, compared with deer, a little safer to hunt.”
An analysis of 29 cougar scat samples taken from Long Beach to the West Coast Trail on Vancouver Island’s west coast showed the following diet: raccoon, 28 per cent; harbour seal, 24 per cent; black-tailed deer, 24 per cent; river otter, 10 per cent; sea lion, seven per cent; mink, four per cent; unknown; three per cent.
Thursday, February 23, 2012