Velella velella is a pelagic colonial hydroid. The float, which is an oval disc, is deep blue in colour and can be up to 10 cm in length. Short tentacles hang down into the water from the float. A thin semicircular fin is set diagonally along the float acting as a sail. This sail gives the animal both its scientific (i.e. from velum, a sail) and its common name, 'by-the-wind-sailor'. The direction of the sail along the float determines which way Velella velella will travel. If the sail runs north-west to south-east along the float it will drift left of the wind direction, if the sail runs south-west to north-east it will drift right of the wind direction. Velella velella feeds on pelagic organisms, including young fish, caught by stinging cells on its tentacles. The sea slug Fiona pinnata , sunfish Mola mola and violet snail Janthina janthina prey upon Velella velella. |
BIRDS:
Arctic Tern, Grey Heron, Mute Swan and cygnets, Sand Martin, Swallow, Chough, Curlew, Oystercatcher, Linnet, Stonechat, Meadow Pipit, Shag
FLORA:
Pineapple Mayweed, Water Mint, Common Scurvy Grass, Redshank, Grass of Parnassus, Harebell, Common Storksbill, Thrift, Creeping Thistle, Marsh Thistle, Spear Thistle, Forget-me-not, Red Bartsia, Red Clover, Eyebright, Ragged Robin, Devil's-bit Scabious, Polypody, Bog Myrtle
OTHER:
Rabbit, Grey Seal
Chough |
Grass of Parnassus |
Lion's Mane Jellyfish |
Polypody with spores |
Water Mint (All photos by Paul Dexter) |
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