One bright Friday morning a small shape floated past the high corner of a nearby building, followed by another . . and then another and then dozens. The spring northward migration of the White Stork (Ciconia ciconia) was underway.
The eastern European white stork migrates along a flyway on the east end of the Mediterranean linking northern Europe to central west Africa. As the cool air of the Mediterrenean sweeps east across the mountains of the west bank it is deflected upward. Bare rocks add thermals to the mix. The storks have a choice to use coastal thermals, or once past the Negev desert, they can follow the winds inland to catch a giant escalator which can take them as far as Istanbul. The mountains may be more reliable – but the coasts hold scores of tasty commercial fish ponds
The method seems to be . . .. catch a mountain wave and or thermal . . . on the west side of the Judean hills.
Circle upward with the rising air – and be carried eastward – gaining altitude with each circle.
As the winds travel east – and before they begin the descent into the Jordan valley – the Storks exit the thermal and glide away - trading altitude for northward distance along the western slope – looking for the next thermal wave to move them upward and northward again.
Can one imagine how many millions of years ago these navigational skills emerged in the DNA of the ancestors of these birds? And were they even birds then, or something more closely resembling dinosaurs?
Sometimes, the numbers of storks is huge, as this video posted on Youtube shows:
Studies of Stork migration patterns are on the internet
Including the application of thermal analysis software used in the sport of gliding
For more information . . . check out Wikipedia!
... a bit more storybook romantic than sea gulls and crows in Alberta ... quite spectacular really ...
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