Tuesday, November 16, 2010

The future is squid

The most interesting thing in last week's episode of Last Chance to See was the close up look at the Humboldt squid. I had read something about these appearing in larger numbers lately, but don't recall ever seeing them on TV before:



The guy in that video claimed he knew a fisherman who, while swimming between boats, had been seriously attacked by a swarm of them. According to Wikipedia (who knows with what accuracy), they aren't really that big danger to humans:
Although Humboldt squid have a reputation of being aggressive, the only reports of aggression towards humans have occurred when reflective diving gear or flashing lights have been present as a provocation. Roger Uzun, a veteran scuba diver and amateur underwater videographer who swam with a swarm of the animals for about 20 minutes, said they seemed to be more curious than aggressive.[5] In reality, there is very likely little danger to humans.
Yet further down in the same article:
Recent footage of shoals of these animals demonstrates a tendency to meet unfamiliar objects aggressively. Having risen to depths of 130–200 metres (430–660 ft) below the surface to feed (up from their typical 700 metre (2,300 ft) diving depth, beyond the range of human diving), they have attacked deep-sea cameras and rendered them inoperable. Reports of recreational scuba divers being attacked by Humboldt Squid have been confirmed.
And more:
There are numerous accounts of the squid attacking fishermen and divers in the area.
Finally, the Wiki entry ends on this slightly worrying note for those who would like their children to be able to swim in the ocean without the risk of attack by swarms of aggressive squid:
A study published in Proceedings of the National Academy of Sciences found that by the end of this century ocean acidification will lower the Humboldt squid's metabolic rate by 31% and activity levels by 45%. This will lead the squid to have to retreat to shallower waters where it can uptake oxygen at higher levels.[24]

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