Wednesday, 19 October 2011

South East!

He's on his way, heading south east. It's great to see him making these bigger distances now. 
He had a good day yesterday - 163 miles or so from Swaledale to somewhere near Downham Market - just 3 good GPS on the way and he did 48 kms between 2pm and 3pm from north of Knottingley to SE of Doncaster. The evening/night 8pm - 9pm signals were non-GPS and in a group near Downham.  The weather in East Anglia is clear and sunny (good for transmitter as well) and light west winds so hope he carries on to continent.
I wonder where he will cross the English Channel. Many ospreys head further west and cross from SW England to the NW tip of France. They then can face a perilous continuous flight across the Bay of Biscay where they can run the risk of missing landfall in Spain and die exhausted out in the Atlantic. 
Maybe Ozwold's more easterly path will take him through France and avoid a journey across the Bay of Biscay. do they really do it? Do we all have an intrinsic compass within us? Interestingly, when I visit schools and ask pupils to point south, the majority usually get it right...sometimes because they are thinking of landmarks, or the position of the sun, but many just say it 'feels' south. 

Another interesting little animal I heard about today is a  little spiral sea-shell which lives in tidal mangrove forests of Kenya. It goes by the lovely name of Cerithidea decollata. or more commonly, the Truncated Mangrove Snail. These little sea shells feed on organic matter on the mangrove mud, but an hour or two before the tide comes in, they crawl off the mud and climb up into the mangrove trees, clustering on the tree-trunks. What is so interesting is they can predict the tides, so that if the tide is a spring tide, (a very high tide) then the snails invariably climb higher. If the tidal reach is lower, the snails to not climb as high. It's not known how the snails 'know' the height of the next tide. But if the snails are moved to a different location, they keep moving in the same pattern, until they become submerged in water and 're-set' their internal body clock. 

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