Sunday, September 13, 2009

Sea Gooseberries

Sea gooseberries, rescued from the beach at Warkworth
Each animal is as transparent as glass, although the tentacles carry a hint of purple
Eight rows of beating hairs, arranged like combs, provide the propulsion. The pink blobs are retracted tentacles
A sea gooseberry swimming left to right and extending one of those lethal tentacles.
A tentacle fully extended, danging below the animal to catch prey,
which is then reeled in
A swimming sea gooseberry, propelled by the rows of 'combs' (which is why these are sometimes called comb jellies), and training tentacles
The rows of cilia make these very manoeuvrable animals -
this one of spinning on the spot, trailing tentacles

Every wave that lapped onto the sandy beach at Warkworth on the Northumberland coast this afternoon washed up scores of blobs of glistening jelly, each about the size of a currant – about 5mm. in diameter. When I scooped some up into a plastic pot and added sea water they turned out to be sea gooseberries, otherwise known as comb jellies. These tiny predatory animals drift in the plankton, suspended by eight rows of constantly beating hairs arranged like combs (called ctenes) and dangle a pair of long tentacles that catch small prey items and draw them up into the animal’s mouth. They are exquisite little organisms, as transparent as glass and flashing with electric blue and green iridescent colours generated by their beating hairs when they catch the sunlight. There must have been tens of thousands of them drift in the plankton just offshore this afternoon. I managed to get some home alive and took some pictures under the microscope, which you can view over at http://beyondthehumaneye.blogspot.com/2009/09/sea-gooseberries.html and I've posted some videos at http://beyondthehumaneye.blogspot.com/2009/09/sea-gooseberry-videos.html

10 comments:

  1. Absolutely fascinating Phil. Such complexities in a tiny creature.

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  2. Hi Keith, I first caught one of these when I was plankton trawling, about 40 years ago, and I've been fascinated with them ever since.

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  3. You never cease to surprise, Phil. Another fascinating piece.

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  4. What a great post Phil. I remember first seeing these tiny jellyfish whilst swimming in the sea on a sunny day at Embleton beach over 30 years ago. I can still remember marvelling at their delicate nature. Linda

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  5. They're amazing animals Emma... like so many of the creatures that live in the plankton

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  6. Hi Linda, I caught these when I was a kid, plankton trawling on the Sussex coast, and kept them in a sea water aquarium. Then I didn't see them again for about 40 years until I saw some in pools of sea water on the beach between Seahouses and Bamburgh. There's also a very impressive larger species called Beroe, shaped like an airship, that I've caught once or twice along the Northumberland coast. The sea gooseberries seem to arrive her in large numbers in late summer. Lovely animals.

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  7. Hi abbey meadows, I could watch these animals swimming all day. Beautiful little movers!

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  8. I recall taking a trip out to the Farnes to look at the grey seals one September a good while ago. I spent as much time staring into the water at the hundreds of sea gooseberries and the larger Beroe that you mention, as I did watching the seals. Just shows - its well worth a Farnes trip outside of the bird season.

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  9. Hi Nyctalus, yes there's something mesmerising about the way these animals move. I once watched a Beroe gliding through the shallows off Embleton beach, drifting through the water like a Zeppelin with flashing neon stripes. Wonderful animals.

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