White storks fly around the Mediterranean because warm air will not lift them over water
A white stork flying from Europe to Africa for winter will not take the short route across the Mediterranean. It relies on rising thermals to soar with little effort, and those columns of warm air do not form over the sea. So flocks funnel through the Strait of Gibraltar or swing east through the Levant instead.
The bird is built for gliding. It stands up to 125 centimetres tall, weighs between 2.3 and 4.5 kilograms and has long, broad wings spanning as much as 2.15 metres. In flapping flight its wingbeats are slow and steady, with the neck stretched forward and the red legs trailing well past its short tail. Males and females look alike, though males tend to be bigger. The plumage is white apart from black flight feathers.
Pairs are monogamous and share nearly everything. Together they build a large nest of sticks, which may be reused for years, take turns warming a clutch of usually four eggs and both feed the chicks. The eggs hatch on different days after about a month, and the young leave the nest after roughly two months, though the parents keep feeding them for another week or more. The diet is wide: insects, fish, frogs, reptiles, small mammals and small birds, mostly snatched from the ground or shallow water.
Its fortunes have tracked human farming. Medieval forest clearance opened up the countryside and helped storks spread, but industrialisation and new agricultural methods drove them out of parts of Europe in the nineteenth and early twentieth centuries. Reintroduction schemes have since brought breeding pairs back to the Netherlands, Switzerland, Sweden and the United Kingdom, among others, and the species is now listed as least concern.
The English naturalist Francis Willughby described it in the seventeenth century from a drawing supplied by Sir Thomas Browne, noting that storms occasionally blew strays to England. Its scientific name simply repeats the Latin word for stork. A fossil bone from Rusinga Island in Lake Victoria suggests storks of this kind are millions of years old.
Source: White stork
