Saturday, March 14, 2009

Don't be a sardine....

Or if you are a sardine (tough luck), whatever you do, don't join in the great sardine run off the coast of South Africa.

One of the treats recently on the Beeb has been another great series from David Attenborough, this time of "Nature's Great Events", and there was one program on the sardine run. It was totally and utterly amazing.

The sardines live in their millions if not billions in the cold waters off the Cape. Usually once a year a current pushes a thread of cold water together with the sardines up close by the coast, and there are predators, thousands upon thousands of them waiting to pounce.

As always with the BBC's nature series the photography was amazing, close up from divers in the water coupled with overhead shots from slow moving spotter planes.

The attack starts with the dolphins breaking off a bait ball away from the main shoal which, at maybe 500 million strong is too distracting and large for most predators. One of the nice things about the dolphins is how aware they are of the divers: for a shark its either eat or ignore but the dolphins roll over to peer curiously at the intruder into their world.

Having created the bait ball, the sardines become vulnerable to more attackers, starting with the gannets diving down in uncountable numbers like bullets. There was once a battle scene in Star Wars where there were meant to be more craft than the eye could take in: well that was nothing to the gannets:

Along side the gannets were the sharks, and for once they ignored each other and concentrated on the poor sardines. It apparently was ok to dive with sharks if the sardines were running but the previous year there had been no run (maybe due to global warming) and the hungry and frustrated sharks took a bite at the camera man's flippers.

Finally the biggest predator of them all turned up, the Brydes whales, swallowing up to 10,000 sardines in one gulp.

Maybe 100 million sardines in total are eaten in the run. An amazing spectacle and worth watching if it comes up on you local station (which, given BBC World's track record it will).

More from the BBC site here and background on Wikipedia here.

2 comments:

Greg and Kris said...

Kris saw this happening live when she lived in Port Elizabeth. It's an amazing event

JP said...

Wow, lucky her!

Apparently there's more whales-eat-fish-drama this week according to the trailer on the great events site:

http://www.bbc.co.uk/naturesgreatevents/