Wednesday, March 09, 2011

Wild sharks


Is that a mouth or what? Now down to the scientific, sharks follow their noses to find prey but they only use one nostril at a time. They head in the direction of the first nostril that copped a whiff of noms even if the other nostril detects a higher concentration of the odor.

The problem of hunting by odor is that odors do not travel through the ocean in a straight line like me to Donut King. The scent breaks up into pieces, floating to different levels, being mixed by water currents so timing is all. The shark hits an odor trail at an angle rather than straight on so by turning in the direction of the 'first whiff nostril' the shark will automatically steer into the ordor patch. And the timing? The difference in timing when each nostril catches a scent can be as small as a tenth of a second.

So if you're hoping their timing is off, here comes the second line of nom finding. They have a sensitive organ called a lateral line, which runs the length of their bodies and picks up vibrations in the water. Functioning in a similar way to the hairs on our skin (are yours standing up right now) but more sensitive, it measures minuscule water flow differences and combined with sense of smell allows the shark to track the odor patches straight to the source.


And even if you think you can out swim those teeth and make it to the boat, look at this photo carefully. The Great White is out of the water and in flight so you could be halfway up the outboard ladder and crunchlunch. This photo was taken at False Bay near Cape Town and it was hard finding one that didn't have a seal, porpoise or bloke in its gob. It brings to mind the immortal words of Chief Brody, "We're gunna need a bigger boat".

8 comments:

Kath Lockett said...

As if the 'sport' of surfing wasn't pointless enough, this article has convinced me that, despite my brothers' urgings, I never want to try it.

Elephant's Child said...

Just the same they are very beautiful, efficient killing machines. I don't think I can begrudge them the odd person. Not as much as I begrudge people who go on shark killing frenzies anyway. Their territory; their right sort of thing.

Thank you for the facts too. I love learning while having fun.

River said...

All I can say is it's a good thing I don't own a swimsuit, so I won't be tempted to go swimming in his environment.
When I was younger, I used to think that great whites were actually white.

Elephant's Child said...

You asked me to email you which I am v happy to do, but can't find your email address on your profile. Have I gone loopy or has it gone?

JahTeh said...

Someone's pinched my email. Ec, it's coppertopj(at)gmail.com. I am doing the bloggy thing.

River, it's that thing, white on the bottom if you're looking up or grey on top if you're looking down, suppposed to be invisible to victims. Sure I'd miss anything that big.

EC, there's been a few nasty attacks over in WA, reminds me very much of 'Jaws'.

Kath, surfing is not a sport, it's insanity masquerading as sport. I have been dumped by a 2 foot wave standing in the shallows. I remember cleaning sand from the orifices for a a week.

Link, I tend to panic if seaweed touches me and I suppose turning head on and stuffing two feet up its nostrils wouldn't help much.
There are great images of these sharks at False Bay but always with some sort of breakfast on the way down.

JahTeh said...

Come to think of it Link, has anybody done any actual 'calm person swimming' research on this advice?

R.H. said...

Sharks don't get cancer.

JahTeh said...

They don't have to, they get everything else.

Link, plan B is don't go in the water. You can't trust anything in the sea, even dolphins will hump your leg, randy little swines.