Wrong way down the migration flyway

The scientists suspect the cause is an error in the genetic migratory programme....

  The scientists suspect the cause is an error in the genetic migratory programme. The flight direction and flight duration are passed on from one generation to the next. This means that migration is the result of a genetic programme, through which bird populations have adjusted to environmental conditions. However, migratory birds can adapt to changes in environmental conditions over just a few generations. Their genes are responsible for the migratory restlessness that drives most of them thousands of kilometres to their winter quarters. Nevertheless, for a long time people were puzzled as to why individual birds of certain species repeatedly went astray. "In these cases, errors have simply occurred in their genetic programming that, if you like, make the birds turn right instead of left.The vagrants can be compared to people who drive the wrong way down the motorway – they fly the wrong way down the intercontinental migration flyway," says Robert Pfeifer, General Secretary of the Ornithological Society in Bavaria. "One can assume that for the majority of these birds, it is a one-way trip. Although there are indications that individual birds do attempt to overwinter in Southern Europe, none of them are likely to make the return journey to Asia. There have been no cases of ringed birds being found again that could provide information about what happens to them." The new research findings also now explain why the only vagrants to have been seen by bird-spotters in Central Europe are long-distance migratory birds from Far East Asia. The genetically programmed journey for short-distance migratory birds from Asia would end somewhere in the west of northern Asia.